93 results on '"Collerton D"'
Search Results
2. Functional and structural brain network correlates of visual hallucinations in Lewy body dementia
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Mehraram, R., Peraza, L.R., Murphy, N.R.E., Cromarty, R.A., Graziadio, S., O’Brien, J.T., Killen, A., Colloby, S.J., Firbank, M., Su, L., Collerton, D., Taylor, J.-P., and Kaiser, M.
- Abstract
Visual hallucinations are a common feature of Lewy body dementia. Previous studies have shown that visual hallucinations are highly specific in differentiating Lewy body dementia from Alzheimer’s disease dementia and Alzheimer-Lewy body mixed pathology cases. Computational models propose that impairment of visual and attentional networks is aetiologically key to the manifestation of visual hallucinations symptomatology. However, there is still a lack of experimental evidence on functional and structural brain network abnormalities associated with visual hallucinations in Lewy body dementia. We used EEG source localisation and Network Based Statistics to assess differential topographical patterns in Lewy body dementia between 25 participants with visual hallucinations and 17 participants without hallucinations. Diffusion tensor imaging was used to assess structural connectivity between thalamus, basal forebrain and cortical regions belonging to the functionally affected network component in the hallucinating group, as assessed with Network Based Statistics. Number of white matter streamlines within the cortex and between subcortical and cortical regions was compared between hallucinating and not hallucinating groups and correlated with average EEG source connectivity of the affected subnetwork. Moreover, modular organisation of the EEG source network was obtained, compared between groups, and tested for correlation with structural connectivity. Network analysis showed that compared to non-hallucinating patients, those with hallucinations feature consistent weakened connectivity within the visual ventral network, and between this network and default mode and ventral attentional networks, but not between or within attentional networks. The occipital lobe was the most functionally disconnected region. Structural analysis yielded significantly affected white matter streamlines connecting the cortical regions to the nucleus basalis of Meynert and the thalamus in hallucinating compared to not hallucinating patients. The number of streamlines in the tract between the basal forebrain and the cortex correlated with cortical functional connectivity in non-hallucinating patients, whilst a correlation emerged for the white matter streamlines connecting the functionally affected cortical regions in the hallucinating group. This study proposes, for the first time, differential functional networks between hallucinating and not hallucinating Lewy body dementia patients, and provides an empirical evidence for existing models of visual hallucinations. Specifically, the outcome of the present study shows that the hallucinating condition is associated with functional network segregation in Lewy body dementia and supports the involvement of the cholinergic system as proposed in the current literature.
- Published
- 2022
3. Serum 25-hydroxyvitamin D and cognitive decline in the very old: the Newcastle 85+ Study
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Granic, A., Hill, T. R., Kirkwood, T. B. L., Davies, K., Collerton, J., Martin-Ruiz, C., von Zglinicki, T., Saxby, B. K., Wesnes, K. A., Collerton, D., Mathers, J. C., and Jagger, C.
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- 2015
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4. Does quality of life vary between mild cognitive impairment subtypes in early Parkinsonʼs disease?: 431
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Lawson, R. A., Yarnall, A. J., Duncan, G. W., Khoo, T. K., Breen, D. P., Barker, R. A., Collerton, D., Taylor, J.-P., and Burn, D. J.
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- 2014
5. Severity of mild cognitive impairment in early Parkinsonʼs disease contributes to poorer quality of life: 430
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Lawson, R. A., Yarnall, A. J., Duncan, G. W., Khoo, T. K., Breen, D. P., Barker, R. A., Collerton, D., Taylor, J.-P., and Burn, D. J.
- Published
- 2014
6. Monoaminergic activities in Lewy Body dementia: Relation to hallucinosis and extrapyramidal features
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Perry, E. K., Marshall, E., Thompson, P., McKeith, I. G., Collerton, D., Fairbairn, A. F., Ferrier, I. N., Irving, D., and Perry, R. H.
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- 1993
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7. Cognitive impairment in Parkinson's disease: impact on quality of life of carers
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Lawson, R A, Yarnall, A J, Johnston, F, Duncan, Gordon, Khoo, T K, Collerton, D, Taylor, J P, and Burn, D J
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Adult ,Aged, 80 and over ,Male ,health care facilities, manpower, and services ,Parkinson's disease ,Parkinson Disease ,social sciences ,Middle Aged ,Neuropsychological Tests ,humanities ,Cognitive impairment ,quality of life ,Surveys and Questionnaires ,Activities of Daily Living ,behavior and behavior mechanisms ,carer ,Humans ,Regression Analysis ,Female ,Cognition Disorders ,health care economics and organizations ,Research Articles ,Research Article ,Aged - Abstract
BACKGROUND: The quality of life (QoL) of informal caregivers of people with Parkinson's disease (PD) (PwP) can be affected by the caring role. Because of cognitive symptoms and diminished activities of daily living, in addition to the management of motor symptoms, carers of PwP and cognitive impairment may experience increased levels of burden and poorer QoL compared with carers of PwP without cognitive impairment. This study aimed to investigate the impact of cognitive impairment in PD upon QoL of carers.METHODS: Approximately 36 months after diagnosis, 66 dyadic couples of PwP and carers completed assessments. PwP completed a schedule of neuropsychological assessments and QoL measures; carers of PwP completed demographic questionnaires and assessments of QoL. Factor scores of attention, memory/executive function and global cognition, as derived by principal component analysis, were used to evaluate cognitive domains.RESULTS: Hierarchical regression analysis found lower Montreal Cognitive Assessment was a significant independent predictor of poorer carer QoL, in addition to number of hours spent caregiving, carer depression and PD motor severity. Attentional deficits accounted for the largest proportion of variance of carer QoL. Carers of PwP and dementia (n = 9) had significantly poorer QoL scores compared with PwP and mild cognitive impairment (n = 18) or normal cognition (n = 39) carers (p CONCLUSIONS: Attentional deficits were the strongest predictor of carer QoL compared with other cognitive predictors. Carers for those with PD dementia reported the poorest QoL. Interventions such as respite or cognitive behavioural therapy to improve mood and self-efficacy in carers may improve carer QoL. © 2016 The Authors. International Journal of Geriatric Psychiatry published by John Wiley & Sons, Ltd.
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- 2016
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8. Lewy body dementia in clinical practice
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Collerton, D., primary, Davies, C., additional, and Thompson, P., additional
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- 1996
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9. Cognitive impairment in Parkinson's disease: impact on quality of life of carers
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Lawson, RA, Yarnall, AJ, Johnston, F, Duncan, GW, Khoo, TK, Collerton, D, Taylor, JP, Burn, DJ, ICICLE-PD Study Group, Lawson, RA [0000-0003-2608-8285], Yarnall, AJ [0000-0002-3126-9163], Burn, DJ [0000-0001-7658-1209], and Apollo - University of Cambridge Repository
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Adult ,Aged, 80 and over ,Male ,health care facilities, manpower, and services ,Parkinson's disease ,Parkinson Disease ,social sciences ,Middle Aged ,Neuropsychological Tests ,humanities ,Cognitive impairment ,quality of life ,Surveys and Questionnaires ,Activities of Daily Living ,behavior and behavior mechanisms ,carer ,Humans ,Regression Analysis ,Female ,Cognition Disorders ,health care economics and organizations ,Aged - Abstract
BACKGROUND: The quality of life (QoL) of informal caregivers of people with Parkinson's disease (PD) (PwP) can be affected by the caring role. Because of cognitive symptoms and diminished activities of daily living, in addition to the management of motor symptoms, carers of PwP and cognitive impairment may experience increased levels of burden and poorer QoL compared with carers of PwP without cognitive impairment. This study aimed to investigate the impact of cognitive impairment in PD upon QoL of carers. METHODS: Approximately 36 months after diagnosis, 66 dyadic couples of PwP and carers completed assessments. PwP completed a schedule of neuropsychological assessments and QoL measures; carers of PwP completed demographic questionnaires and assessments of QoL. Factor scores of attention, memory/executive function and global cognition, as derived by principal component analysis, were used to evaluate cognitive domains. RESULTS: Hierarchical regression analysis found lower Montreal Cognitive Assessment was a significant independent predictor of poorer carer QoL, in addition to number of hours spent caregiving, carer depression and PD motor severity. Attentional deficits accounted for the largest proportion of variance of carer QoL. Carers of PwP and dementia (n = 9) had significantly poorer QoL scores compared with PwP and mild cognitive impairment (n = 18) or normal cognition (n = 39) carers (p < 0.01). CONCLUSIONS: Attentional deficits were the strongest predictor of carer QoL compared with other cognitive predictors. Carers for those with PD dementia reported the poorest QoL. Interventions such as respite or cognitive behavioural therapy to improve mood and self-efficacy in carers may improve carer QoL. © 2016 The Authors. International Journal of Geriatric Psychiatry published by John Wiley & Sons, Ltd.
- Published
- 2017
10. Serum 25-hydroxyvitamin D and cognitive decline in the very old: the Newcastle 85+ Study
- Author
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Granic, A., primary, Hill, T. R., additional, Kirkwood, T. B. L., additional, Davies, K., additional, Collerton, J., additional, Martin-Ruiz, C., additional, von Zglinicki, T., additional, Saxby, B. K., additional, Wesnes, K. A., additional, Collerton, D., additional, Mathers, J. C., additional, and Jagger, C., additional
- Published
- 2014
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11. Complex visual hallucinations and attentional performance in eye disease and dementia: a test of the Perception and Attention Deficit model
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Makin, S. M., primary, Redman, J., additional, Mosimann, U. P., additional, Dudley, R., additional, Clarke, M. P., additional, Colbourn, C., additional, and Collerton, D., additional
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- 2013
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12. The assessment of cognition in visually impaired older adults
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Killen, A., primary, Firbank, M. J., additional, Collerton, D., additional, Clarke, M., additional, Jefferis, J. M., additional, Taylor, J.-P., additional, McKeith, I. G., additional, and Mosimann, U. P., additional
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- 2012
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13. Specific attentional impairments and complex visual hallucinations in eye disease
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Graham, G, primary, Dean, J, additional, Mosimann, UP, additional, Colbourn, C, additional, Dudley, R, additional, Clarke, M, additional, and Collerton, D, additional
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- 2011
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14. Consensus guidelines for the clinical and pathologic diagnosis of dementia with Lewy bodies (DLB)
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McKeith, I.G., primary, Galasko, D., additional, Kosaka, K., additional, Perry, E.K., additional, Dickson, D.W., additional, Hansen, L.A., additional, Salmon, D.P., additional, Lowe, J., additional, Mirra, S.S., additional, Byrne, E.J., additional, Lennox, G., additional, Quinn, N.P., additional, Edwardson, J.A., additional, Ince, P.G., additional, Bergeron, C., additional, Burns, A., additional, Miller, B.L., additional, Lovestone, S., additional, Collerton, D., additional, Jansen, E.N.H., additional, Ballard, C., additional, de Vos, R.A.I., additional, Wilcock, G.K., additional, Jellinger, K.A., additional, and Perry, R.H., additional
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- 1996
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15. Psychological therapies for depression with older adults: a qualitative review.
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Davies C and Collerton D
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In this article, we qualitatively review the effects of psychological treatments for older adults. Group comparison studies indicate that all psychological treatments produce equivalent statistically significant effects. Studies using measures of individual change report more modest, although still valuable results, with again no differences between types of intervention. Self-report measures of change are more conservative than observer-rated measures. There are few data on the comparative cost-efficacy of different therapies, although psychological therapies in general have been shown to reduce subsequent use of medical services. Limited studies have indicated that psychological therapies may be less cost-effective than medication. [ABSTRACT FROM AUTHOR]
- Published
- 1997
16. Cholinergic function and intellectual decline in Alzheimer's disease
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Collerton, D., primary
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- 1986
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17. Rational drug treatment of dementia.
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Collerton, D, primary
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- 1985
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18. Episodic Visual Hallucinations, Inference and Free Energy.
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Collerton D, Tsuda I, and Nara S
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Understandings of how visual hallucinations appear have been highly influenced by generative approaches, in particular Friston's Active Inference conceptualization. Their core proposition is that these phenomena occur when hallucinatory expectations outweigh actual sensory data. This imbalance occurs as the brain seeks to minimize informational free energy, a measure of the distance between predicted and actual sensory data in a stationary open system. We review this approach in the light of old and new information on the role of environmental factors in episodic hallucinations. In particular, we highlight the possible relationship of specific visual triggers to the onset and offset of some episodes. We use an analogy from phase transitions in physics to explore factors which might account for intermittent shifts between veridical and hallucinatory vision. In these triggered forms of hallucinations, we suggest that there is a transient disturbance in the normal one-to-one correspondence between a real object and the counterpart perception such that this correspondence becomes between the real object and a hallucination. Generative models propose that a lack of information transfer from the environment to the brain is one of the key features of hallucinations. In contrast, we submit that specific information transfer is required at onset and offset in these cases. We propose that this transient one-to-one correspondence between environment and hallucination is mediated more by aberrant discriminative than by generative inference. Discriminative inference can be conceptualized as a process for maximizing shared information between the environment and perception within a self-organizing nonstationary system. We suggest that generative inference plays the greater role in established hallucinations and in the persistence of individual hallucinatory episodes. We further explore whether thermodynamic free energy may be an additional factor in why hallucinations are temporary. Future empirical research could productively concentrate on three areas. Firstly, subjective perceptual changes and parallel variations in brain function during specific transitions between veridical and hallucinatory vision to inform models of how episodes occur. Secondly, systematic investigation of the links between environment and hallucination episodes to probe the role of information transfer in triggering transitions between veridical and hallucinatory vision. Finally, changes in hallucinatory episodes over time to elucidate the role of learning on phenomenology. These empirical data will allow the potential roles of different forms of inference in the stages of hallucinatory episodes to be elucidated.
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- 2024
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19. Non-clinical hallucinations and mental imagery across sensory modalities.
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Rogers LW, Yeebo M, Collerton D, Moseley P, and Dudley R
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- Humans, Female, Male, Adult, Young Adult, Adolescent, Visual Perception, Auditory Perception, Hallucinations psychology, Imagination, Self Report
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Introduction: Vivid mental imagery has been proposed to increase the likelihood of experiencing hallucinations. Typically, studies have employed a modality general approach to mental imagery which compares imagery across multiple domains (e.g., visual, auditory and tactile) to hallucinations in multiple senses. However, modality specific imagery may be a better predictor of hallucinations in the same domain. The study examined the contribution of imagery to hallucinations in a non-clinical sample and specifically whether imagery best predicted hallucinations at a modality general or modality specific level., Methods: In study one, modality general and modality specific accounts of the imagery-hallucination relationship were contrasted through application of self-report measures in a sample of 434 students. Study two used a subsample ( n = 103) to extend exploration of the imagery-hallucinations relationship using a performance-based imagery task., Results: A small to moderate modality general relationship was observed between self-report imagery and hallucination proneness. There was only evidence of a modality specific relationship in the tactile domain. Performance-based imagery measures were unrelated to hallucinations and self-report imagery., Conclusions: Mental imagery may act as a modality general process increasing hallucination proneness. The observed distinction between self-report and performance-based imagery highlights the difficulty of accurately measuring internal processes.
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- 2024
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20. Functional connectivity in Lewy body disease with visual hallucinations.
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Firbank MJ, Collerton D, Morgan KD, Schumacher J, Donaghy PC, O'Brien JT, Thomas A, and Taylor JP
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- Humans, Aged, Brain, Hallucinations etiology, Brain Mapping, Cognition, Magnetic Resonance Imaging, Lewy Body Disease complications, Lewy Body Disease diagnostic imaging
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Background and Purpose: Visual hallucinations are a common, potentially distressing experience of people with Lewy body disease (LBD). The underlying brain changes giving rise to visual hallucinations are not fully understood, although previous models have posited that alterations in the connectivity between brain regions involved in attention and visual processing are critical., Methods: Data from 41 people with LBD and visual hallucinations, 48 with LBD without visual hallucinations and 60 similarly aged healthy comparator participants were used. Connections were investigated between regions in the visual cortex and ventral attention, dorsal attention and default mode networks., Results: Participants with visual hallucinations had worse cognition and motor function than those without visual hallucinations. In those with visual hallucinations, reduced functional connectivity within the ventral attention network and from the visual to default mode network was found. Connectivity strength between the visual and default mode network correlated with the number of correct responses on a pareidolia task, and connectivity within the ventral attention network with visuospatial performance., Conclusions: Our results add to evidence of dysfunctional connectivity in the visual and attentional networks in those with LBD and visual hallucinations., (© 2023 The Authors. European Journal of Neurology published by John Wiley & Sons Ltd on behalf of European Academy of Neurology.)
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- 2024
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21. Understanding visual hallucinations: A new synthesis.
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Collerton D, Barnes J, Diederich NJ, Dudley R, Ffytche D, Friston K, Goetz CG, Goldman JG, Jardri R, Kulisevsky J, Lewis SJG, Nara S, O'Callaghan C, Onofrj M, Pagonabarraga J, Parr T, Shine JM, Stebbins G, Taylor JP, Tsuda I, and Weil RS
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- Humans, Brain, Hallucinations psychology, Attention Deficit Disorder with Hyperactivity
- Abstract
Despite decades of research, we do not definitively know how people sometimes see things that are not there. Eight models of complex visual hallucinations have been published since 2000, including Deafferentation, Reality Monitoring, Perception and Attention Deficit, Activation, Input, and Modulation, Hodological, Attentional Networks, Active Inference, and Thalamocortical Dysrhythmia Default Mode Network Decoupling. Each was derived from different understandings of brain organisation. To reduce this variability, representatives from each research group agreed an integrated Visual Hallucination Framework that is consistent with current theories of veridical and hallucinatory vision. The Framework delineates cognitive systems relevant to hallucinations. It allows a systematic, consistent, investigation of relationships between the phenomenology of visual hallucinations and changes in underpinning cognitive structures. The episodic nature of hallucinations highlights separate factors associated with the onset, persistence, and end of specific hallucinations suggesting a complex relationship between state and trait markers of hallucination risk. In addition to a harmonised interpretation of existing evidence, the Framework highlights new avenues of research, and potentially, new approaches to treating distressing hallucinations., Competing Interests: Conflicts of interest The following authors report no competing interests: James Barnes, Robert Dudley, Nico Diederich, Dominic ffytche, Karl Friston, Simon Lewis, Shigetoshi Nara, Claire O’Callaghan, Javier Pagonabarraga, James M Shine, Ichiro Tsuda. Daniel Collerton has received royalty payments from Wiley publishers. Christopher C Goetz has received faculty stipends from the International Parkinson and Movement Disorder Society, Guest professorship honoraria provided by University of Chicago and Illinois State Neurological Society, and a stipend as Volume Editor from Elsevier Publishers. He has also received royalty payments from Elsevier Publishers and Wolters Kluwer Publishers. Jennifer G Goldman has received grant/research support from Acadia Pharmaceuticals and honoraria from Medscape. Renaud Jardri has been invited to scientific meetings and expert boards by Lundbeck, Janssen and Otsuka. Jaime Kulisevsky has received fees for presentations or advisory boards from: Teva, UCB, Roche, Abbvie, Zambon, Bial, Sanofii and Neuroderm. Marco Onofrj has served on the scientific advisory boards of GlaxoSmithKline, Novartis, Lundbeck, Eisai, Valeant, Medtronic, and Newron; has received speaker honoraria from Zambon, the World Parkinson Congress, the Movement Disorder Society, and the Atypical Dementias congress; publishing royalties from Springer; was an invited guest and lecturer for the Mental Disorders in Parkinson Disease Congress; serves on the editorial board of Medicine (Baltimore) and Frontiers in Neuroscience; has been employed as a speaker for Boehringer Ingelheim, GlaxoSmithKline, UCB, and Zambon; and has received research support from the Italian Ministry of Health and the Italian Ministry of Education. Glenn Stebbins received compensation for consulting and advisory board membership from Acadia Pharmaceuticals, Adamas Pharmaceuticals, Biogen, Ceregene, CHDI Management, Neurocrine Biosciences, Pfizer, Tools-4-Patients, Ultragenyx and the Sunshine Care Foundation. John-Paul Taylor has received speaker fees from GE Healthcare. He has consulted for Kirin Kyowa and Sosei-Heptares. Rimona S Weil has received speaking honoraria from GE Healthcare and writing honoraria from Britannia., (Copyright © 2023 The Authors. Published by Elsevier Ltd.. All rights reserved.)
- Published
- 2023
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22. What is the frequency and nature of visual hallucinations in non-clinical participants?
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Aynsworth C, Rolinson J, Pervez M, Collerton D, and Dudley R
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- Humans, Cross-Sectional Studies, Emotions, Surveys and Questionnaires, Hallucinations psychology, Psychotic Disorders therapy
- Abstract
Objectives: There is a paucity of psychological treatments for visual hallucinations (VH). A key aspect in the psychological treatment of hallucination-related distress is normalisation to explain that these experiences are commonplace and can be non-distressing. In order to normalise VH, it is vital that more is known about VH in non-clinical populations. This study investigated the prevalence, content, context, appraisals, distress, and behavioural reactions to VH in a non-clinical sample., Design: A cross-sectional study was conducted., Methods: 466 students completed the Multi-Modality Unusual Sensory Experiences Questionnaire-VH subscale with additional contextual follow-up questions., Results: Of the 466 participants, 395 (84.8%) reported anomalous visual experiences. 176 (37.77%) participants reported VH similar to the content seen in psychosis. Of the overall sample, 17.38% felt their experience met the VH definition. Participants mainly saw figures, when alone and in the evening. Participants endorsed normalising appraisals: 112 out of 176 (78.87%) believed their mind was playing tricks on them and 83 (58.45%) believed they were tired. However, many also believed the VH was a threat to their mental (66, 46.48%) or physical well-being (41, 28.87%). These negative appraisals were associated with distress., Conclusion: VH are seemingly common in non-clinical populations and are similar in a number of ways to those of people with psychosis. Awareness that VH occur on a continuum could normalise people's experiences and reduce their negative appraisals and related distress., (© 2022 The British Psychological Society.)
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- 2023
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23. Transcranial Direct Current Stimulation in the Treatment of Visual Hallucinations in Charles Bonnet Syndrome: A Randomized Placebo-Controlled Crossover Trial.
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daSilva Morgan K, Schumacher J, Collerton D, Colloby S, Elder GJ, Olsen K, Ffytche DH, and Taylor JP
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- Humans, Cross-Over Studies, Hallucinations therapy, Hallucinations diagnosis, Hallucinations etiology, Charles Bonnet Syndrome complications, Charles Bonnet Syndrome therapy, Transcranial Direct Current Stimulation adverse effects, Transcranial Direct Current Stimulation methods, Vision, Low etiology
- Abstract
Objective: To investigate the potential therapeutic benefits and tolerability of inhibitory transcranial direct current stimulation (tDCS) on the remediation of visual hallucinations in Charles Bonnet syndrome (CBS)., Design: Randomized, double-masked, placebo-controlled crossover trial., Participants: Sixteen individuals diagnosed with CBS secondary to visual impairment caused by eye disease experiencing recurrent visual hallucinations., Intervention: All participants received 4 consecutive days of active and placebo cathodal stimulation (current density: 0.29 mA/cm
2 ) to the visual cortex (Oz) over 2 defined treatment weeks, separated by a 4-week washout period., Main Outcome Measures: Ratings of visual hallucination frequency and duration following active and placebo stimulation, accounting for treatment order, using a 2 × 2 repeated-measures model. Secondary outcomes included impact ratings of visual hallucinations and electrophysiological measures., Results: When compared with placebo treatment, active inhibitory stimulation of visual cortex resulted in a significant reduction in the frequency of visual hallucinations measured by the North East Visual Hallucinations Interview, with a moderate-to-large effect size. Impact measures of visual hallucinations improved in both placebo and active conditions, suggesting support and education for CBS may have therapeutic benefits. Participants who demonstrated greater occipital excitability on electroencephalography assessment at the start of treatment were more likely to report a positive treatment response. Stimulation was found to be tolerable in all participants, with no significant adverse effects reported, including no deterioration in preexisting visual impairment., Conclusions: Findings indicate that inhibitory tDCS of visual cortex may reduce the frequency of visual hallucinations in people with CBS, particularly individuals who demonstrate greater occipital excitability prior to stimulation. tDCS may offer a feasible intervention option for CBS with no significant side effects, warranting larger-scale clinical trials to further characterize its efficacy., (Copyright © 2022 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.)- Published
- 2022
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24. Functional and structural brain network correlates of visual hallucinations in Lewy body dementia.
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Mehraram R, Peraza LR, Murphy NRE, Cromarty RA, Graziadio S, O'Brien JT, Killen A, Colloby SJ, Firbank M, Su L, Collerton D, Taylor JP, and Kaiser M
- Subjects
- Brain pathology, Diffusion Tensor Imaging, Hallucinations etiology, Humans, Alzheimer Disease pathology, Lewy Body Disease complications, Lewy Body Disease diagnostic imaging, Lewy Body Disease pathology
- Abstract
Visual hallucinations are a common feature of Lewy body dementia. Previous studies have shown that visual hallucinations are highly specific in differentiating Lewy body dementia from Alzheimer's disease dementia and Alzheimer-Lewy body mixed pathology cases. Computational models propose that impairment of visual and attentional networks is aetiologically key to the manifestation of visual hallucinations symptomatology. However, there is still a lack of experimental evidence on functional and structural brain network abnormalities associated with visual hallucinations in Lewy body dementia. We used EEG source localization and network based statistics to assess differential topographical patterns in Lewy body dementia between 25 participants with visual hallucinations and 17 participants without hallucinations. Diffusion tensor imaging was used to assess structural connectivity between thalamus, basal forebrain and cortical regions belonging to the functionally affected network component in the hallucinating group, as assessed with network based statistics. The number of white matter streamlines within the cortex and between subcortical and cortical regions was compared between hallucinating and not hallucinating groups and correlated with average EEG source connectivity of the affected subnetwork. Moreover, modular organization of the EEG source network was obtained, compared between groups and tested for correlation with structural connectivity. Network analysis showed that compared to non-hallucinating patients, those with hallucinations feature consistent weakened connectivity within the visual ventral network, and between this network and default mode and ventral attentional networks, but not between or within attentional networks. The occipital lobe was the most functionally disconnected region. Structural analysis yielded significantly affected white matter streamlines connecting the cortical regions to the nucleus basalis of Meynert and the thalamus in hallucinating compared to not hallucinating patients. The number of streamlines in the tract between the basal forebrain and the cortex correlated with cortical functional connectivity in non-hallucinating patients, while a correlation emerged for the white matter streamlines connecting the functionally affected cortical regions in the hallucinating group. This study proposes, for the first time, differential functional networks between hallucinating and not hallucinating Lewy body dementia patients, and provides empirical evidence for existing models of visual hallucinations. Specifically, the outcome of the present study shows that the hallucinating condition is associated with functional network segregation in Lewy body dementia and supports the involvement of the cholinergic system as proposed in the current literature., (© The Author(s) 2022. Published by Oxford University Press on behalf of the Guarantors of Brain.)
- Published
- 2022
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25. Cognition, hallucination severity and hallucination-specific insight in neurodegenerative disorders and eye disease.
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Montagnese M, Vignando M, Collerton D, Ffytche D, Mosimann UP, Taylor JP, daSilva Morgan K, and Urwyler P
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- Cognition, Hallucinations, Humans, Dementia complications, Eye Diseases complications, Parkinson Disease complications
- Abstract
Introduction: Hallucinations occur across neurodegenerative disorders, with increasing severity, poorer cognition and impaired hallucination-specific insight associated with worse outcomes and faster disease progression. It remains unclear how changes in cognition, temporal aspects of hallucinations, hallucination-specific insight and distress relate to each other. Methods: Extant samples of patients experiencing visual hallucinations were included in the analyses: Parkinson's Disease ( n = 103), Parkinson's Disease Dementia ( n = 41), Dementia with Lewy Bodies ( n = 27) and Eye Disease ( n = 113). We explored the relationship between factors of interest with Spearman's correlations and random-effect linear models. Results: Spearman's correlation analyses at the whole-group level showed that higher hallucination-specific insight was related to higher MMSE score ( r
s = 0.39, p < 0.001) and less severe hallucinations ( rs = -0.28, p < .01). Linear mixed-models controlling for diagnostic group showed that insight was related to higher MMSE ( p < .001), to hallucination severity ( p = 0.003), and to VH duration ( p = 0.04). Interestingly, insight was linked to the distress component but not the frequency component of severity. No significant relationship was found between MMSE and hallucination severity in these analyses. Conclusion: Our findings highlight the importance of hallucination-specific insight, distress and duration across groups. A better understanding of the role these factors play in VH may help with the development of future therapeutic interventions trans-diagnostically.- Published
- 2022
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26. Investigation of structural brain changes in Charles Bonnet Syndrome.
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Firbank MJ, daSilva Morgan K, Collerton D, Elder GJ, Parikh J, Olsen K, Schumacher J, Ffytche D, and Taylor JP
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- Blindness, Brain diagnostic imaging, Cross-Sectional Studies, Diffusion Tensor Imaging, Hallucinations diagnostic imaging, Humans, Charles Bonnet Syndrome complications, Charles Bonnet Syndrome diagnostic imaging, Eye Diseases complications
- Abstract
Background and Objectives: In Charles Bonnet Syndrome (CBS), visual hallucinations (VH) are experienced by people with sight loss due to eye disease or lesional damage to early visual pathways. The aim of this cross-sectional study was to investigate structural brain changes using magnetic resonance imaging (MRI) in CBS., Methods: Sixteen CBS patients, 17 with eye disease but no VH, and 19 normally sighted people took part. Participants were imaged on a 3T scanner, with 1 mm resolution T1 weighted structural imaging, and diffusion tensor imaging with 64 diffusion directions., Results: The three groups were well matched for age, sex and cognitive scores (MMSE). The two eye disease groups were matched on visual acuity. Compared to the sighted controls, we found reduced grey matter in the occipital cortex in both eye disease groups. We also found reductions of fractional anisotropy and increased diffusivity in widespread areas, including occipital tracts, the corpus callosum, and the anterior thalamic radiation. We did not find any significant differences between the eye disease participants with VH versus without VH, but did observe a negative association between hippocampal volume and VH severity in the CBS group., Discussion: Our findings suggest that although there are cortical and subcortical effects associated with sight loss, structural changes do not explain the occurrence of VHs. CBS may relate instead to connectivity or excitability changes in brain networks linked to vision., (Copyright © 2022 The Authors. Published by Elsevier Inc. All rights reserved.)
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- 2022
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27. Exploring Bottom-Up Visual Processing and Visual Hallucinations in Parkinson's Disease With Dementia.
- Author
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Murphy N, Killen A, Gupta RK, Graziadio S, Rochester L, Firbank M, Baker MR, Allan C, Collerton D, Taylor JP, and Urwyler P
- Abstract
Visual hallucinations (VH) are a common symptom of Parkinson's disease with dementia (PDD), affecting up to 65% of cases. Integrative models of their etiology posit that a decline in executive control of the visuo-perceptual system is a primary mechanism of VH generation. The role of bottom-up processing in the manifestation of VH in this condition is still not clear although visual evoked potential (VEP) differences have been associated with VH at an earlier stage of PD. Here we compared the amplitude and latency pattern reversal VEPs in healthy controls ( n = 21) and PDD patients ( n = 34) with a range of VH severities. PDD patients showed increased N2 latency relative to controls, but no significant differences in VEP measures were found for patients reporting complex VH (CVH) ( n = 17) compared to those without VH. Our VEP findings support previous reports of declining visual system physiology in PDD and some evidence of visual system differences between patients with and without VH. However, we did not replicate previous findings of a major relationship s between the integrity of the visual pathway and VH., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest. The reviewer DF declared past co-authorship and research collaboration with several of the authors DC, J-PT, PU, MF to the handling Editor., (Copyright © 2021 Murphy, Killen, Gupta, Graziadio, Rochester, Firbank, Baker, Allan, Collerton, Taylor and Urwyler.)
- Published
- 2021
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28. A Review of Multimodal Hallucinations: Categorization, Assessment, Theoretical Perspectives, and Clinical Recommendations.
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Montagnese M, Leptourgos P, Fernyhough C, Waters F, Larøi F, Jardri R, McCarthy-Jones S, Thomas N, Dudley R, Taylor JP, Collerton D, and Urwyler P
- Subjects
- Humans, Bipolar Disorder complications, Bipolar Disorder physiopathology, Hallucinations classification, Hallucinations diagnosis, Hallucinations etiology, Hallucinations physiopathology, Psychotic Disorders complications, Psychotic Disorders physiopathology, Schizophrenia complications, Schizophrenia physiopathology
- Abstract
Hallucinations can occur in different sensory modalities, both simultaneously and serially in time. They have typically been studied in clinical populations as phenomena occurring in a single sensory modality. Hallucinatory experiences occurring in multiple sensory systems-multimodal hallucinations (MMHs)-are more prevalent than previously thought and may have greater adverse impact than unimodal ones, but they remain relatively underresearched. Here, we review and discuss: (1) the definition and categorization of both serial and simultaneous MMHs, (2) available assessment tools and how they can be improved, and (3) the explanatory power that current hallucination theories have for MMHs. Overall, we suggest that current models need to be updated or developed to account for MMHs and to inform research into the underlying processes of such hallucinatory phenomena. We make recommendations for future research and for clinical practice, including the need for service user involvement and for better assessment tools that can reliably measure MMHs and distinguish them from other related phenomena., (© The Author(s) 2020. Published by Oxford University Press on behalf of the Maryland Psychiatric Research Center.)
- Published
- 2021
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29. Hallucinations in Older Adults: A Practical Review.
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Badcock JC, Larøi F, Kamp K, Kelsall-Foreman I, Bucks RS, Weinborn M, Begemann M, Taylor JP, Collerton D, O'Brien JT, El Haj M, Ffytche D, and Sommer IE
- Subjects
- Aged, Humans, Aging, Hallucinations diagnosis, Hallucinations therapy
- Abstract
Older adults experience hallucinations in a variety of social, physical, and mental health contexts. Not everyone is open about these experiences, as hallucinations are surrounded with stigma. Hence, hallucinatory experiences in older individuals are often under-recognized. They are also commonly misunderstood by service providers, suggesting that there is significant scope for improvement in the training and practice of professionals working with this age group. The aim of the present article is to increase knowledge about hallucinations in older adults and provide a practical resource for the health and aged-care workforce. Specifically, we provide a concise narrative review and critique of (1) workforce competency and training issues, (2) assessment tools, and (3) current treatments and management guidelines. We conclude with a brief summary including suggestions for service and training providers and future research., (© The Author(s) 2020. Published by Oxford University Press on behalf of the Maryland Psychiatric Research Center.)
- Published
- 2020
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30. Visual hallucinations in neurological and ophthalmological disease: pathophysiology and management.
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O'Brien J, Taylor JP, Ballard C, Barker RA, Bradley C, Burns A, Collerton D, Dave S, Dudley R, Francis P, Gibbons A, Harris K, Lawrence V, Leroi I, McKeith I, Michaelides M, Naik C, O'Callaghan C, Olsen K, Onofrj M, Pinto R, Russell G, Swann P, Thomas A, Urwyler P, Weil RS, and Ffytche D
- Subjects
- Dementia complications, Dementia physiopathology, Dementia therapy, Eye Diseases physiopathology, Eye Diseases therapy, Hallucinations physiopathology, Hallucinations therapy, Humans, Nervous System Diseases physiopathology, Nervous System Diseases therapy, Parkinson Disease complications, Parkinson Disease physiopathology, Parkinson Disease therapy, Eye Diseases complications, Hallucinations etiology, Nervous System Diseases complications
- Abstract
Visual hallucinations are common in older people and are especially associated with ophthalmological and neurological disorders, including dementia and Parkinson's disease. Uncertainties remain whether there is a single underlying mechanism for visual hallucinations or they have different disease-dependent causes. However, irrespective of mechanism, visual hallucinations are difficult to treat. The National Institute for Health Research (NIHR) funded a research programme to investigate visual hallucinations in the key and high burden areas of eye disease, dementia and Parkinson's disease, culminating in a workshop to develop a unified framework for their clinical management. Here we summarise the evidence base, current practice and consensus guidelines that emerged from the workshop.Irrespective of clinical condition, case ascertainment strategies are required to overcome reporting stigma. Once hallucinations are identified, physical, cognitive and ophthalmological health should be reviewed, with education and self-help techniques provided. Not all hallucinations require intervention but for those that are clinically significant, current evidence supports pharmacological modification of cholinergic, GABAergic, serotonergic or dopaminergic systems, or reduction of cortical excitability. A broad treatment perspective is needed, including carer support. Despite their frequency and clinical significance, there is a paucity of randomised, placebo-controlled clinical trial evidence where the primary outcome is an improvement in visual hallucinations. Key areas for future research include the development of valid and reliable assessment tools for use in mechanistic studies and clinical trials, transdiagnostic studies of shared and distinct mechanisms and when and how to treat visual hallucinations., Competing Interests: Competing interests: Roger A Barker has acted as a consultant to UCB, Living Cell Technologies, BlueRock Therapeutics, Sana Biotechnology, FCDI, Novo Nordisk and Cellino. Clare Bradley is director and majority shareholder of Health Psychology Research Ltd, which licences her patient-reported outcome measures for others to use and manages their linguistic validation into other languages. She receives royalties when existing language versions of her questionnaires are licensed to commercial companies. Her College currently receives research grants to support her research from ViiVHealthCare and from Medtronic. She has recently received speaker fees from Astellas and routinely advises many pharmaceutical companies and contract research organisations on the use of her questionnaires in their clinical trials. Robert Dudley reports delivering training workshops and has written books about CBT, for which he has received fees, and reports delivering CBT in the National Health Service (NHS). Paul Francis has received speaking fees from Suven and Nutricia. Iracema Leroi has received speaking fees from Eisai, Boehringer Ingelheim, GE Healthcare, GlaxoSmithKline, Shire and Lundbeck. Ian McKeith has acted as a consultant for GE Healthcare, Sumitomo Dainippon Pharma, Sanofi and Eisai. John O’Brien has acted as a consultant for TauRx, Axon, GE Healthcare and Eisai. Marco Onofrj has served on the scientific advisory boards of GlaxoSmithKline, Novartis, Lundbeck, Eisai, Valeant, Medtronic and Newron; has received speaker honoraria from Zambon, the World Parkinson Congress, the Movement Disorder Society and the Atypical Dementias congress; was an invited guest and lecturer for the Mental Disorders in Parkinson Disease Congress; serves on the editorial board of Medicine (Baltimore); has been employed as a speaker for Boehringer Ingelheim, GlaxoSmithKline, UCB and Zambon and has received research support from the Italian Ministry of Health and the Italian Ministry of Education. Rimona S Weil has received speaker fees from GE Healthcare. John-Paul Taylor has received speaker fees from GE Healthcare and acted as a consultant for Heptares-Sosei. No other authors declared any conflicts., (© Author(s) (or their employer(s)) 2020. Re-use permitted under CC BY. Published by BMJ.)
- Published
- 2020
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31. Pathological Changes to the Subcortical Visual System and its Relationship to Visual Hallucinations in Dementia with Lewy Bodies.
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Erskine D, Taylor JP, Thomas A, Collerton D, McKeith I, Khundakar A, Attems J, and Morris C
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- Humans, Nerve Net pathology, Dementia pathology, Hallucinations pathology, Lewy Body Disease pathology
- Published
- 2019
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32. Prevalence and characteristics of multi-modal hallucinations in people with psychosis who experience visual hallucinations.
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Dudley R, Aynsworth C, Cheetham R, McCarthy-Jones S, and Collerton D
- Subjects
- Adult, Female, Hallucinations psychology, Humans, Male, Prevalence, Psychotic Disorders psychology, Young Adult, Hallucinations diagnosis, Hallucinations epidemiology, Psychotic Disorders diagnosis, Psychotic Disorders epidemiology
- Abstract
Hallucinations can occur in single or multiple sensory modalities. Historically, greater attention has been paid to single sensory modality experiences with a comparative neglect of hallucinations that occur across two or more sensory modalities (multi-modal hallucinations). With growing evidence suggesting that visual hallucinations may be experienced along with other hallucinations, this study aimed to explore multi-modal hallucinations in a sample of people with psychotic disorders who reported visual hallucinations (n = 22). No participants reported just visual hallucinations i.e. all reported related or unrelated auditory hallucinations. Twenty-one participants reported multi-modal hallucinations that were serial in nature, whereby they saw visual hallucinations and heard unrelated auditory hallucinations at other times. Nineteen people out of the twenty two also reported simultaneous multi-modal hallucinations, with the most common being an image that talked to and touched them. Multi-modal related and simultaneous hallucinations appeared to be associated with greater conviction that the experiences were real, and greater distress. Theoretical and clinical implications of multi-modal hallucinations are discussed., (Copyright © 2018 Elsevier B.V. All rights reserved.)
- Published
- 2018
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33. The utility and application of electrophysiological methods in the study of visual hallucinations.
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daSilva Morgan K, Elder GJ, Ffytche DH, Collerton D, and Taylor JP
- Subjects
- Hallucinations physiopathology, Humans, Visual Cortex physiopathology, Electrodiagnosis methods, Hallucinations diagnosis
- Abstract
Visual hallucinations (VH) are a common symptom in multiple clinical and non-clinical populations. Although structural and functional neuroimaging has informed the understanding of VH, temporal resolution is limited. Electrophysiological techniques provide a complementary perspective on dynamic and temporal aspects of neural functioning, offering greater insight into the mechanisms underlying their formation. In this review we examine and critically evaluate the emerging evidence base utilising electrophysiological approaches in the study of VH. Overall, increased visual system excitability, dysfunctional visual processing and network connectivity, and cholinergic dysfunction have been consistently observed in VH-prone pathologies. However, a major limitation is in the lack of robust experimental studies and the reliance on single case reports. We conclude that electrophysiology provides tentative evidence for the contribution of bottom-up, top-down, and network dysfunction in the aetiology of VH, supporting several existing VH models. Furthermore, we discuss how electrophysiology has been directly utilised in specific clinical interventions for VH. Further exploration utilising electrophysiology in combination with, for example, neuroimaging will help better understand VH aetiology while aiding in the development of novel therapeutic interventions for this difficult to treat symptom., (Copyright © 2018 International Federation of Clinical Neurophysiology. Published by Elsevier B.V. All rights reserved.)
- Published
- 2018
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34. Reduced occipital GABA in Parkinson disease with visual hallucinations.
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Firbank MJ, Parikh J, Murphy N, Killen A, Allan CL, Collerton D, Blamire AM, and Taylor JP
- Subjects
- Aged, Aged, 80 and over, Cognition Disorders etiology, Creatine metabolism, Female, Gray Matter diagnostic imaging, Humans, Image Processing, Computer-Assisted, Magnetic Resonance Imaging, Magnetic Resonance Spectroscopy, Male, Mental Status Schedule, Middle Aged, Oxygen blood, Prospective Studies, Retrospective Studies, Visual Acuity physiology, White Matter diagnostic imaging, Hallucinations complications, Occipital Lobe metabolism, Parkinson Disease complications, Parkinson Disease pathology, gamma-Aminobutyric Acid metabolism
- Abstract
Objective: To investigate the relationship between visual hallucinations in Parkinson disease (PD) and levels of γ-aminobutyric acid (GABA) in the primary visual cortex., Methods: We utilized magnetic resonance spectroscopy to investigate occipital GABA levels in 36 participants with PD, 19 with and 17 without complex visual hallucinations, together with 20 healthy controls without hallucinations. In addition, we acquired T1-weighted MRI, whole-brain fMRI during a visual task, and diffusion tensor imaging., Results: We found lower GABA+/creatine in PD with visual hallucinations (0.091 ± 0.010) vs those without (0.101 ± 0.010) and controls (0.099 ± 0.010) ( F
2,49 = 4.5; p = 0.016). Reduced gray matter in the hallucinations group was also observed in the anterior temporal lobe. Although there were widespread reductions in white matter integrity in the visual hallucinations group, this was no longer significant after controlling for cognitive function., Conclusions: The data suggest that reduced levels of GABA are associated with visual hallucinations in PD and implicate changes to the ventral visual stream in the genesis of visual hallucinations. Modulation of visual cortical excitability through, for example, pharmacologic intervention, may be a promising treatment avenue to explore., (Copyright © 2018 The Author(s). Published by Wolters Kluwer Health, Inc. on behalf of the American Academy of Neurology.)- Published
- 2018
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35. Coping with Cognitive Impairment in People with Parkinson's Disease and Their Carers: A Qualitative Study.
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Lawson RA, Collerton D, Taylor JP, Burn DJ, and Brittain KR
- Abstract
Cognitive impairment is common in Parkinson's disease (PD). However, the psychosocial impact of living and coping with PD and cognitive impairment in people with PD and their carers have not been explored. This paper draws on a qualitative study that explores the subjective impact of cognitive impairment on people with PD and their carers. Thirty-six one-to-one interviews were completed; people with PD were from three groups: normal cognition, mild cognitive impairment, and dementia. Data collection and analysis were iterative, and verbatim transcripts were analysed using thematic analysis. Themes were interpreted in consultation with coping and adaptation theory. The analysis revealed four main themes: threats to identity and role, predeath grief and feelings of loss in carers, success and challenges to coping in people with PD, and problem-focused coping and finding meaning in caring. Our data highlight how cognitive impairment can threaten an individual's self-perception; the ostensible effects of cognitive impairment depended on the impact individual's perceived cognitive impairment had on their daily lives. For carers, cognitive impairment had a greater emotional impact than the physical symptoms of PD. The discussion that developed around protective factors provides possible opportunities for future interventions, such as psychological therapies to improve successful adjustment.
- Published
- 2018
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36. Seeing for ourselves: Insights into the development of moral behaviour from models of visual perception and misperception.
- Author
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Collerton D and Perry E
- Subjects
- Consciousness, Humans, Morals, Unconsciousness, Vision, Ocular, Visual Perception
- Abstract
Parallels from visual processing support Doris's cognitive architecture underlying moral agency. Unconscious visual processes change with conscious reflection. The sparse and partial representations of vision, its illusions, and hallucinations echo biases in moral reasoning and behaviour. Traditionally, unconscious moral processes are developed by teaching and reflection. Modern neuroscience could bypass reflection and directly influence unconscious processes, creating new dangers.
- Published
- 2018
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37. Cognitive impairment in Parkinson's disease: impact on quality of life of carers.
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Lawson RA, Yarnall AJ, Johnston F, Duncan GW, Khoo TK, Collerton D, Taylor JP, and Burn DJ
- Subjects
- Activities of Daily Living psychology, Adult, Aged, Aged, 80 and over, Female, Humans, Male, Middle Aged, Neuropsychological Tests, Regression Analysis, Surveys and Questionnaires, Cognition Disorders etiology, Parkinson Disease psychology, Quality of Life psychology
- Abstract
Background: The quality of life (QoL) of informal caregivers of people with Parkinson's disease (PD) (PwP) can be affected by the caring role. Because of cognitive symptoms and diminished activities of daily living, in addition to the management of motor symptoms, carers of PwP and cognitive impairment may experience increased levels of burden and poorer QoL compared with carers of PwP without cognitive impairment. This study aimed to investigate the impact of cognitive impairment in PD upon QoL of carers., Methods: Approximately 36 months after diagnosis, 66 dyadic couples of PwP and carers completed assessments. PwP completed a schedule of neuropsychological assessments and QoL measures; carers of PwP completed demographic questionnaires and assessments of QoL. Factor scores of attention, memory/executive function and global cognition, as derived by principal component analysis, were used to evaluate cognitive domains., Results: Hierarchical regression analysis found lower Montreal Cognitive Assessment was a significant independent predictor of poorer carer QoL, in addition to number of hours spent caregiving, carer depression and PD motor severity. Attentional deficits accounted for the largest proportion of variance of carer QoL. Carers of PwP and dementia (n = 9) had significantly poorer QoL scores compared with PwP and mild cognitive impairment (n = 18) or normal cognition (n = 39) carers (p < 0.01)., Conclusions: Attentional deficits were the strongest predictor of carer QoL compared with other cognitive predictors. Carers for those with PD dementia reported the poorest QoL. Interventions such as respite or cognitive behavioural therapy to improve mood and self-efficacy in carers may improve carer QoL. © 2016 The Authors. International Journal of Geriatric Psychiatry published by John Wiley & Sons, Ltd., (© 2016 The Authors. International Journal of Geriatric Psychiatry published by John Wiley & Sons, Ltd.)
- Published
- 2017
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38. Measures of visual hallucinations: Review and recommendations.
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Aynsworth C, Collerton D, and Dudley R
- Subjects
- Humans, Hallucinations diagnosis, Psychiatric Status Rating Scales standards
- Abstract
Background: Studies designed to investigate visual hallucinations (VH) require reliable and valid measures that can appropriately capture peoples' experiences. This review aimed to assess the psychometric rigour and usefulness of VH measures., Method: A systematic literature search was carried out against inclusion criteria (e.g. more than one specific question on VH, measures for adults in clinical and non-clinical populations). Eighteen measures were identified and rated against an adapted evaluation grid, which included essential criteria such as clear purpose and definition, psychometric properties including reliability and validity, and appropriate exploration of visual hallucinations., Results: Measures could be categorised into 3 groups; those for general psychotic symptoms, those for all hallucinations, or those specifically for visual hallucinations. With one exception (the North East Visual Hallucinations Inventory), the measures were considered to be limited as they often targeted one population and hence lacked generalisability, or were limited in the characteristics of the visions that were described, or that psychometric properties were not adequately evaluated., Conclusions: Measures of VH require further development. The need to establish a clearer definition of VH is essential to provide clarity and consistency within research and practice. Measures need to demonstrate good psychometric properties to indicate robustness whilst being sensitive to change to help in the evaluation of treatments. Other recommendations include developing cross-cultural measures and involving service users in item development., (Copyright © 2017 Elsevier Ltd. All rights reserved.)
- Published
- 2017
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39. Reality monitoring performance and the role of visual imagery in visual hallucinations.
- Author
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Aynsworth C, Nemat N, Collerton D, Smailes D, and Dudley R
- Subjects
- Adult, Case-Control Studies, Female, Hallucinations complications, Humans, Male, Psychotic Disorders complications, Young Adult, Confusion psychology, Hallucinations psychology, Imagination, Psychotic Disorders psychology, Reality Testing
- Abstract
Background: Auditory Hallucinations may arise from people confusing their own inner speech with external spoken speech. People with visual hallucinations (VH) may similarly confuse vivid mental imagery with external events. This paper reports two experiments exploring confusion between internal and external visual material., Method: Experiment 1 examined reality monitoring in people with psychosis; those with visual hallucinations (n = 16) and those without (n = 15). Experiment 2 used two non-clinical groups of people with high or low predisposition to VH (HVH, n = 26, LVH, n = 21). All participants completed the same reality monitoring task. Participants in Experiment 2 also completed measures of imagery., Results: Psychosis patients with VH demonstrated biased reality monitoring, where they misremembered items that had been presented as words as having been presented as pictures. Patients without VH did not show this bias. In Experiment 2, the HVH group demonstrated the same bias in reality monitoring that psychosis patients with VH had shown. The LVH group did not show this bias. In addition, the HVH group reported more vivid imagery and particularly more negative imagery., Conclusions: Both studies found that people with visual hallucinations or prone-ness to such experiences confused their inner visual experiences with external images. Vivid imagery was also related to proneness to VH. Hence, vivid imagery and reality monitoring confusion could be contributory factors to understanding VH., (Copyright © 2017 Elsevier Ltd. All rights reserved.)
- Published
- 2017
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40. The Structure and Measurement of Unusual Sensory Experiences in Different Modalities: The Multi-Modality Unusual Sensory Experiences Questionnaire (MUSEQ).
- Author
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Mitchell CAA, Maybery MT, Russell-Smith SN, Collerton D, Gignac GE, and Waters F
- Abstract
Hallucinations and other unusual sensory experiences (USE) can occur in all modalities in the general population. Yet, the existing literature is dominated by investigations into auditory hallucinations ("voices"), while other modalities remain under-researched. Furthermore, there is a paucity of measures which can systematically assess different modalities, which limits our ability to detect individual and group differences across modalities. The current study explored such differences using a new scale, the Multi-Modality Unusual Sensory Experiences Questionnaire (MUSEQ). The MUSEQ is a 43-item self-report measure which assesses USE in six modalities: auditory, visual, olfactory, gustatory, bodily sensations, and sensed presence. Scale development and validation involved a total of 1,300 participants, which included: 513 students and community members for initial development, 32 individuals with schizophrenia spectrum disorder or bipolar disorder for validation, 659 students for factor replication, and 96 students for test-retest reliability. Confirmatory factor analyses showed that a correlated-factors model and bifactor model yielded acceptable model fit, while a unidimensional model fitted poorly. These findings were confirmed in the replication sample. Results showed contributions from a general common factor, as well as modality-specific factors. The latter accounted for less variance than the general factor, but could still detect theoretically meaningful group differences. The MUSEQ showed good reliability, construct validity, and could discriminate non-clinical and clinical groups. The MUSEQ offers a reliable means of measuring hallucinations and other USE in six different modalities.
- Published
- 2017
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41. Compensatory shifts in visual perception are associated with hallucinations in Lewy body disorders.
- Author
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Bowman AR, Bruce V, Colbourn CJ, and Collerton D
- Abstract
Visual hallucinations are a common, distressing, and disabling symptom of Lewy body and other diseases. Current models suggest that interactions in internal cognitive processes generate hallucinations. However, these neglect external factors. Pareidolic illusions are an experimental analogue of hallucinations. They are easily induced in Lewy body disease, have similar content to spontaneous hallucinations, and respond to cholinesterase inhibitors in the same way. We used a primed pareidolia task with hallucinating participants with Lewy body disorders (n = 16), non-hallucinating participants with Lewy body disorders (n = 19), and healthy controls (n = 20). Participants were presented with visual "noise" that sometimes contained degraded visual objects and were required to indicate what they saw. Some perceptions were cued in advance by a visual prime. Results showed that hallucinating participants were impaired in discerning visual signals from noise, with a relaxed criterion threshold for perception compared to both other groups. After the presentation of a visual prime, the criterion was comparable to the other groups. The results suggest that participants with hallucinations compensate for perceptual deficits by relaxing perceptual criteria, at a cost of seeing things that are not there, and that visual cues regularize perception. This latter finding may provide a mechanism for understanding the interaction between environments and hallucinations.
- Published
- 2017
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42. Visual Hallucinations in Older People: Appraisals but not Content or Phenomenology Influence Distress.
- Author
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Lai S, Bruce V, and Collerton D
- Subjects
- Adaptation, Psychological, Aged, Awareness, Emotions, Female, Humans, Interview, Psychological methods, Male, Middle Aged, Psychotic Disorders psychology, Self Report, Hallucinations psychology, Stress, Psychological psychology
- Abstract
Background: A previous study (Gauntlett-Gilbert and Kuipers, 2005) has suggested that distress associated with complex visual hallucinations (CVHs) in younger adults with psychosis may more strongly relate to appraisals of meaning than to the content of the hallucination. However, visual hallucinations are most commonly seen in the disorders of later life, where this relationship has not been investigated., Aim: To establish if there is a relationship between appraisals of CVHs and distress in older, non-psychotic people with CVHs., Method: All variables were measured using a semi-structured interview and were compared between a high distress group (n = 16) and a low distress group (n = 19)., Results: The high distress group rated their hallucinations as more malevolent and omnipotent, with greater negative implications for physical and mental health. There was no significant difference between groups on ratings of hallucination content (independently rated), frequency, awareness or control., Conclusion: Appraisals of CVHs are linked to distress.
- Published
- 2016
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43. What Is the Link Between Hallucinations, Dreams, and Hypnagogic-Hypnopompic Experiences?
- Author
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Waters F, Blom JD, Dang-Vu TT, Cheyne AJ, Alderson-Day B, Woodruff P, and Collerton D
- Subjects
- Brain physiology, Humans, Nerve Net physiology, Brain physiopathology, Dreams physiology, Eye Diseases physiopathology, Hallucinations physiopathology, Nerve Net physiopathology, Parkinson Disease physiopathology, Schizophrenia physiopathology, Sleep, REM physiology
- Abstract
By definition, hallucinations occur only in the full waking state. Yet similarities to sleep-related experiences such as hypnagogic and hypnopompic hallucinations, dreams and parasomnias, have been noted since antiquity. These observations have prompted researchers to suggest a common aetiology for these phenomena based on the neurobiology of rapid eye movement (REM) sleep. With our recent understanding of hallucinations in different population groups and at the neurobiological, cognitive and interpersonal levels, it is now possible to draw comparisons between the 2 sets of experiences as never before. In the current article, we make detailed comparisons between sleep-related experiences and hallucinations in Parkinson's disease, schizophrenia and eye disease, at the levels of phenomenology (content, sensory modalities involved, perceptual attributes) and of brain function (brain activations, resting-state networks, neurotransmitter action). Findings show that sleep-related experiences share considerable overlap with hallucinations at the level of subjective descriptions and underlying brain mechanisms. Key differences remain however: (1) Sleep-related perceptions are immersive and largely cut off from reality, whereas hallucinations are discrete and overlaid on veridical perceptions; and (2) Sleep-related perceptions involve only a subset of neural networks implicated in hallucinations, reflecting perceptual signals processed in a functionally and cognitively closed-loop circuit. In summary, both phenomena are non-veridical perceptions that share some phenomenological and neural similarities, but insufficient evidence exists to fully support the notion that the majority of hallucinations depend on REM processes or REM intrusions into waking consciousness., (© The Author 2016. Published by Oxford University Press on behalf of the Maryland Psychiatric Research Center. All rights reserved. For permissions, please email: journals.permissions@oup.com.)
- Published
- 2016
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44. Is Seeing Believing? The Process of Change During Cognitive-behavioural Therapy for Distressing Visual Hallucinations.
- Author
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Wilson R, Collerton D, Freeston M, Christodoulides T, and Dudley R
- Subjects
- Female, Follow-Up Studies, Hallucinations complications, Humans, Male, Psychotic Disorders complications, Treatment Outcome, Cognitive Behavioral Therapy methods, Hallucinations psychology, Hallucinations therapy, Psychotic Disorders psychology, Psychotic Disorders therapy
- Abstract
Unlabelled: People with psychosis often report distressing visual hallucinations (VH). In contrast to auditory hallucinations, there is little empirical evidence on effective interventions. The effectiveness of a novel-focused cognitive-behavioural therapy (CBT) intervention for VH was explored using a multiple baseline single case design with four participants. Change to individual appraisals, emotional and behavioural responses to VH were measured with daily diaries kept throughout the baseline and intervention phase lasting up to 16 sessions. Maintenance of change was tracked during a follow-up period of one month. Changes in appraisals, distress and response in accordance with the theory was evident in two out of four of the cases. However, change occurred within the baseline phase that limited the conclusions that change could be attributed to CBT alone. There was some evidence of clinically significant change and reliable change for two out of four of the cases at follow-up on one of the standardized psychiatric assessments. The research reported here has theoretical and clinical implications for refinement of the model and interventions for distressing VH. Copyright © 2015 John Wiley & Sons, Ltd., Key Practitioner Message: Distressing visual hallucinations (VH) are a relatively common symptom of psychosis. Visual hallucinations seem to be associated with greater impairment and disability. We have no specific treatment for VH. The appraisal of the visual experience and the behavioural response is important in maintaining the distress. Cognitive-behavioural therapy for VH at present has limited value., (Copyright © 2015 John Wiley & Sons, Ltd.)
- Published
- 2016
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45. Cognitive decline and quality of life in incident Parkinson's disease: The role of attention.
- Author
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Lawson RA, Yarnall AJ, Duncan GW, Breen DP, Khoo TK, Williams-Gray CH, Barker RA, Collerton D, Taylor JP, and Burn DJ
- Subjects
- Aged, Aged, 80 and over, Cognitive Dysfunction epidemiology, Female, Follow-Up Studies, Humans, Male, Middle Aged, Neuropsychological Tests, Parkinson Disease epidemiology, Attention, Cognitive Dysfunction diagnosis, Cognitive Dysfunction psychology, Parkinson Disease diagnosis, Parkinson Disease psychology, Quality of Life psychology
- Abstract
Introduction: Parkinson's disease dementia (PDD) is associated with poorer quality of life (QoL). Prior to the onset of PDD, many patients experience progressive cognitive impairment. There is a paucity of longitudinal studies investigating the effects of cognitive decline on QoL. This study aimed to determine the longitudinal impact of cognitive change on QoL in an incident PD cohort., Methods: Recently diagnosed patients with PD (n = 212) completed a schedule of neuropsychological assessments and QoL measures; these were repeated after 18 (n = 190) and 36 months (n = 158). Mild cognitive impairment (PD-MCI) was classified with reference to the Movement Disorder Society criteria. Principal component analysis was used to reduce 10 neuropsychological tests to three cognitive factors: attention, memory/executive function, and global cognition., Results: Baseline PD-MCI was a significant contributor to QoL (β = 0.2, p < 0.01). For those subjects (9%) who developed dementia, cognitive function had a much greater impact on QoL (β = 10.3, p < 0.05). Multivariate modelling showed attentional deficits had the strongest predictive power (β = -2.3, p < 0.01); brief global tests only modestly predicted decline in QoL (β = -0.4, p < 0.01)., Conclusions: PD-MCI was associated with poorer QoL over three years follow up. Cognitive impairment had a greater impact on QoL in individuals who developed dementia over follow-up. Impaired attention was a significant determinant of QoL in PD. Interventions which improve concentration and attention in those with PD could potentially improve QoL., (Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.)
- Published
- 2016
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46. Visual Hallucinations in Eye Disease and Lewy Body Disease.
- Author
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Urwyler P, Nef T, Müri R, Archibald N, Makin SM, Collerton D, Taylor JP, Burn D, McKeith I, and Mosimann UP
- Subjects
- Aged, Case-Control Studies, Comorbidity, Cross-Sectional Studies, Female, Humans, Male, Sex Factors, United Kingdom epidemiology, Eye Diseases epidemiology, Hallucinations epidemiology, Lewy Body Disease epidemiology, Parkinson Disease epidemiology
- Abstract
Objectives: Visual hallucinations (VH) most commonly occur in eye disease (ED), Parkinson disease (PD), and Lewy body dementia (LBD). The phenomenology of VH is likely to carry important information about the brain areas within the visual system generating them., Methods: Data from five controlled cross-sectional VH studies (164 controls, 135 ED, 156 PD, 79 [PDD 48 + DLB 31] LBD) were combined and analyzed. The prevalence, phenomenology, frequency, duration, and contents of VH were compared across diseases and sex., Results: Simple VH were most common in ED patients (ED 65% versus LBD 22% versus PD 9%, χ(2) = 31.43, df = 2, p < 0.001), whereas complex VH were more common in LBD (LBD 76% versus ED 38%, versus PD 28%, χ(2) = 96.80, df = 2, p < 0.001). The phenomenology of complex VH was different across diseases and sex. ED patients reported more "flowers" (ED 21% versus LBD 6% versus PD 0%, χ(2) = 10.04, df = 2, p = 0.005) and "body parts" (ED 40% versus LBD 17% versus PD 13%, χ(2) = 11.14, df = 2, p = 0.004); in contrast, LBD patients reported "people" (LBD 85% versus ED 67% versus PD 63%, χ(2) = 6.20, df = 2, p = 0.045) and "animals/insects" (LBD 50% versus PD 42% versus ED 21%, χ(2) = 9.76, df = 2, p = 0.008). Men reported more "machines" (13% versus 2%, χ(2) = 6.94, df = 1, p = 0.008), whereas women reported more "family members/children" (48% versus 29%, χ(2) = 5.10, df = 1, p = 0.024)., Conclusions: The phenomenology of VH is likely related to disease-specific dysfunctions within the visual system and to past, personal experiences., (Copyright © 2016 American Association for Geriatric Psychiatry. Published by Elsevier Inc. All rights reserved.)
- Published
- 2016
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47. Visual Priming and Visual Hallucinations in Parkinson's Disease. Evidence for Normal Top-Down Processes.
- Author
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Straughan S, Collerton D, and Bruce V
- Subjects
- Adult, Aged, Case-Control Studies, Female, Hallucinations complications, Hallucinations diagnosis, Humans, Male, Middle Aged, Neuropsychological Tests, Parkinson Disease complications, Attention physiology, Cues, Hallucinations physiopathology, Parkinson Disease psychology, Perceptual Disorders etiology
- Abstract
Background: Visual hallucinations (VH) are common in Parkinson's disease (PD) and are associated with increased morbidity and mortality. Current explanations for VH in PD suggest combined impairments in top-down attentional and bottom-up perceptual processes, which allow the passive "release" of stored images. Alternative models in other disorders have suggested that top-down factors may actively encourage hallucinations. In order to explore the interaction between top-down and bottom-up visual processing in PDVH, we developed novel experimental priming tasks in which top-down verbal cues were used to prime the bottom-up recognition of partial or ambiguous pictures., Method: Two groups of PD participants with (PD + VH, n = 16), and without VH (PD - VH, n = 20) were compared to a group of healthy older adults (NC, n = 20) on 3 novel measures of visual priming., Results: All tasks showed significant priming effects. The PD + VH group was more impaired at accurately identifying silhouette and fragmented images compared to the PD - VH group. There were no differences in priming between the 2 PD groups., Conclusions: The study showed that VH in PD are not associated with relatively greater top-down activation, and that the interaction between top-down and bottom-up processes is intact., (© The Author(s) 2015.)
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- 2016
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48. Patient and Informant Views on Visual Hallucinations in Parkinson Disease.
- Author
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Urwyler P, Nef T, Müri RM, Killen A, Collerton D, Burn D, McKeith I, and Mosimann UP
- Subjects
- Aged, Aged, 80 and over, Cross-Sectional Studies, Female, Hallucinations epidemiology, Humans, Male, Middle Aged, Parkinson Disease epidemiology, Prevalence, Psychiatric Status Rating Scales, Psychometrics, United Kingdom epidemiology, Caregivers psychology, Hallucinations complications, Hallucinations psychology, Parkinson Disease complications, Parkinson Disease psychology, Self Report standards
- Abstract
Objective: Visual hallucinations (VHs) are a very personal experience, and it is not clear whether information about them is best provided by informants or patients. Some patients may not share their hallucinatory experiences with caregivers to avoid distress or for fear of being labeled insane, and others do not have informants at all, which limits the use of informant-based questionnaires. The aim of this study was to compare patient and caregiver views about VHs in Parkinson disease (PD), using the North-East Visual Hallucinations Interview (NEVHI)., Methods: Fifty-nine PD patient-informant pairs were included. PD patients and informants were interviewed separately about VHs using the NEVHI. Informants were additionally interviewed using the four-item version of the Neuropsychiatric Inventory. Inter-reliability and concurrent validity of the different measures were compared., Results: VHs were more commonly reported by patients than informants. The inter-rater agreement between NEVHI-patient and NEVHI-informant was moderate for complex VHs (Cohen's kappa = 0.44; 95% confidence interval [CI]: 0.13-0.75; t = 3.43, df = 58, p = 0.001) and feeling of presence (Cohen's kappa = 0.35; 95% CI: 0.00-0.70; t = 2.75, df = 58, p = 0.006), but agreement was poor for illusions (Cohen's kappa = 0.25; 95% CI: -0.07-0.57; t = 2.36, df = 58, p = 0.018) and passage hallucinations (Cohen's kappa = 0.16; 95% CI: -0.04-0.36; t = 2.26, df = 58, p = 0.024)., Conclusion: When assessing VHs in PD patients, it is best to rely on patient information, because not all patients share the details of their hallucinations with their caregivers., (Copyright © 2015 American Association for Geriatric Psychiatry. Published by Elsevier Inc. All rights reserved.)
- Published
- 2015
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49. An exploratory study of the effectiveness of memory AIDS for older people living in supported accommodation.
- Author
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Collerton D, Forster E, and Packham D
- Subjects
- Aged, Aged, 80 and over, Cognition Disorders psychology, Female, Humans, Male, Surveys and Questionnaires, Adaptation, Psychological, Cognition Disorders rehabilitation, Memory physiology, Self-Help Devices
- Abstract
There is increasing evidence that electronic and other aids can support older people's memory. In an effectiveness study, we explored whether assistive technologies could benefit 200 potential beneficiaries in a naturalistic setting. We first interviewed 50 participants to assess needs and preferences for memory aids, then researched, developed and trialled specific aids, and finally administered a follow-up questionnaire assessing future use of aids. Matching aids to needs was not easy. Relatively few people were interested in trailing aids. Simpler aids were most successful. Participants were curious about electronic aids, but found them too complicated and not adapted enough to their needs. Assistance from other people was necessary to prompt use of all types of aids. Future effectiveness studies should focus on longer trials with greater training and support for participants, a wider range of technologies, and more promotion of possible benefits., (© The Author(s) 2012.)
- Published
- 2014
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50. Severity of mild cognitive impairment in early Parkinson's disease contributes to poorer quality of life.
- Author
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Lawson RA, Yarnall AJ, Duncan GW, Khoo TK, Breen DP, Barker RA, Collerton D, Taylor JP, and Burn DJ
- Subjects
- Aged, Attention, Executive Function, Female, Humans, Male, Memory, Middle Aged, Neuropsychological Tests, Predictive Value of Tests, Space Perception, Statistics, Nonparametric, Cognitive Dysfunction etiology, Parkinson Disease complications, Parkinson Disease psychology, Quality of Life psychology
- Abstract
Background: Poor quality of life (QoL) is a feature of people with Parkinson's disease (PD) who develop dementia. The relationship between mild cognitive impairment in PD (PD-MCI) and QoL is less clear. To address this, we studied the impact of varying severities of cognitive impairment on QoL in a cohort of non-demented patients with early PD., Method: Patients with newly diagnosed PD (n = 219) and age and sex matched healthy controls (n = 99) completed a schedule of neuropsychological tests, in addition to scales assessing QoL (PDQ-39), depression, sleep, neuropsychiatric symptoms and a clinical examination. The Movement Disorder Society criteria were used to define and classify PD-MCI., Results: Participants with PD-MCI were significantly older than those with normal cognition, had more severe motor symptoms, scored higher for depression and had poorer quality of life. Logistic regression showed that mild cognitive impairment, independent of other factors, was an indicator of poorer QoL. Using cognitive performance 2.0 standard deviations (SD) below normative data as a cut-off to define PD-MCI, there was a significant difference in QoL scores between patients with PD-MCI and those classified as having normal cognition. Subjects with less severe mild cognitive impairment did not exhibit significant differences in QoL., Conclusions: PD-MCI is a significant, independent factor contributing to poorer QoL in patients with newly diagnosed PD. Those classified with greatest impairment (2.0 SD below normal values) have lower QoL. This has implications for clinical practice and future interventions targeting cognitive impairments., (Copyright © 2014 The Authors. Published by Elsevier Ltd.. All rights reserved.)
- Published
- 2014
- Full Text
- View/download PDF
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