23 results on '"Yágüez L"'
Search Results
2. Differential effect of Huntington's and Parkinson's diseases in programming motor sequences of varied lengths
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Yágüez, L., Lange, H. W., and Hömberg, V.
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- 2006
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3. IMAGING BRAIN PROCESSING OF PAINFUL VISCERAL SENSATION DURING NEGATIVE MOOD INDUCTION: 301
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Coen, S. J., Gregory, L. J., Yágüez, L., Mitterschiffthaler, M. T., Brammer, M., Williams, S. C.R., and Aziz, Q.
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- 2006
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4. EFFECTS OF DISTRACTION ON BRAIN ACTIVITY FOLLOWING PAINFUL VISCERAL STIMULATION: 302
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Coen, S. J., Gregory, L. J., Yágüez, L., Brammer, M., Williams, S. C.R., and Aziz, Q.
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- 2006
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5. Cognitive modulation of the cerebral processing of human oesophageal sensation using functional magnetic resonance imaging
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Gregory, L J, Yágüez, L, Williams, S C R, Altmann, C, Coen, S J, Ng, V, Brammer, M J, Thompson, D G, and Aziz, Q
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- 2003
6. Staff working with people who have intellectual disabilities within secure hospitals: expressed emotion and its relationship to burnout, stress and coping.
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Langdon PE, Yágüez L, Kuipers E, Langdon, Peter E, Yágüez, Lidia, and Kuipers, Elizabeth
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Studies involving professional carers of people with mental health problems have investigated the relationship between burnout, job satisfaction, the coping strategies employed by carers, and expressed emotion (EE). We undertook a similar study involving carers of adults with intellectual disabilities detained within a secure hospital. Twenty-seven nursing staff completed a Five Minute Speech Sample regarding a keyworked client. EE was coded, and measures of coping strategies, burnout, attitudes to psychiatric treatment and job satisfaction were administered. Sixty-three percent of the sample were coded as having high EE. These subjects reported significantly higher levels of depersonalization and lower levels of personal accomplishment. They used coping strategies more frequently: specifically they reported trying to reorganize their work and to seek support from others. The results are discussed in light of the findings of previous studies. It is noted that the study was not causal and the sample size was small. [ABSTRACT FROM AUTHOR]
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- 2007
7. The effect of acute hypoglycemia on brain function and activation: a functional magnetic resonance imaging study.
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Rosenthal, J. Miranda, Rosenthal, J M, Amiel, S A, Yágüez, L, Bullmore, E, Hopkins, D, Evans, M, Pernet, A, Reid, H, Giampietro, V, Andrew, C M, Suckling, J, Simmons, A, and Williams, S C
- Subjects
BRAIN function localization ,HYPOGLYCEMIA ,BRAIN mapping - Abstract
The authors' aim was to examine the regional anatomy of brain activation by cognitive tasks commonly used in hypoglycemia research and to assess the effect of acute hypoglycemia on these in healthy volunteers. Eight right-handed volunteers performed a set of cognitive tasks-finger tapping (FT), simple reaction time (SRT), and four-choice reaction time (4CRT)-twice during blood oxygen level-dependent (BOLD) functional magnetic resonance imaging of the brain on two occasions. In study 1 (n = 6), plasma glucose was maintained at euglycemia (5 mmol/l) throughout. In study 2 (n = 6), plasma glucose was reduced to 2.5 mmol/l for the second set. Performance of the tasks resulted in specific group brain activation maps. During hypoglycemia, FT slowed (P = 0.026), with decreased BOLD activation in right premotor cortex and supplementary motor area and left hippocampus and with increased BOLD activation in left cerebellum and right frontal pole. Although there was no significant change in SRT, BOLD activation was reduced in right cerebellum and visual cortex. The 4CRT deteriorated (P = 0.020), with reduction in BOLD activation in motor and visual systems but increased BOLD signal in a large area of the left parietal association cortex, a region involved in planning. Hypoglycemia impairs simple brain functions and is associated with task-specific localized reductions in brain activation. For a task with greater cognitive load, the increased BOLD signal in planning areas is compatible with recruitment of brain regions in an attempt to limit dysfunction. Further investigation of these mechanisms may help devise rational treatment strategies to limit cortical dysfunction during acute iatrogenic hypoglycemia. [ABSTRACT FROM AUTHOR]
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- 2001
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8. 302 EFFECTS OF DISTRACTION ON BRAIN ACTIVITY FOLLOWING PAINFUL VISCERAL STIMULATION
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Coen, S.J., Gregory, L.J., Yágüez, L., Brammer, M., Williams, S.C.R., and Aziz, Q.
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- 2006
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9. 301 IMAGING BRAIN PROCESSING OF PAINFUL VISCERAL SENSATION DURING NEGATIVE MOOD INDUCTION
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Coen, S.J., Gregory, L.J., Yágüez, L., Mitterschiffthaler, M.T., Brammer, M., Williams, S.C.R., and Aziz, Q.
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- 2006
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10. A mental route to motor learning: Improving trajectorial kinematics through imagery training
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Yágüez, L, Nagel, D, Hoffman, H, Canavan, A.G.M, Wist, E, and Hömberg, V
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- 1998
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11. Increased superior temporal activation associated with external misattributions of self-generated speech in schizophrenia.
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Fu CH, Brammer MJ, Yágüez L, Allen P, Matsumoto K, Johns L, Weinstein S, Borgwardt S, Broome M, McGuire PK, van Haren N, Fu, Cynthia H Y, Brammer, Michael J, Yágüez, Lidia, Allen, Paul, Matsumoto, Kazunori, Johns, Louise, Weinstein, Sara, Borgwardt, Stefan, and Broome, Matthew
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- 2008
12. Cognitive predictors of cognitive change following bilateral subthalamic nucleus deep brain stimulation in Parkinson's disease.
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Yágüez L, Costello A, Moriarty J, Hulse N, Selway R, Clough C, Samuel M, and Ashkan K
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- Aged, Female, Humans, Male, Middle Aged, Subthalamic Nucleus surgery, Cognitive Dysfunction complications, Deep Brain Stimulation adverse effects, Neuropsychological Tests, Parkinson Disease complications, Parkinson Disease therapy
- Abstract
The beneficial effects of deep brain stimulation (DBS) of the subthalamic nucleus (STN) for the motor symptoms in advanced Parkinson's disease (PD) are well established. Early in PD, mild cognitive impairment is present in a proportion of patients. Hence, it can also be present in PD patients considered for DBS. The potential impact of even a modest decline post-surgically is a concern because it could result in impaired cognitive function. Therefore, attempts to determine which pre-operative cognitive measures predict post-operative cognitive change warrant further attention. We report our findings in a cohort of 30 routinely operated non-demented patients who underwent detailed neuropsychological assessments on average 7.1 months before and 9.4 months after STN DBS. We report the individual and group differences pre- and post-DBS. Stepwise regression analysis was used to analyse the best cognitive predictors of post-operative cognitive changes. We describe our data in relation to published normative data. Post-STN DBS, the immediate story recall component of verbal memory was the most affected cognitive function showing a significant decline in its group mean with a large effect size. The best predictors for this change were pre-surgical list learning and Full Scale Intelligence Quotient. These results suggest that non-demented patients, with even mild impairments in both general intellectual functions and list learning, may be at greater risk of decline in other aspects of verbal memory after STN DBS. Pre-existing mild executive dysfunction was not influenced post-operatively. These findings may help selection and consent for STN DBS., (Copyright © 2013 Elsevier Ltd. All rights reserved.)
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- 2014
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13. The effects on cognitive functions of a movement-based intervention in patients with Alzheimer's type dementia: a pilot study.
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Yágüez L, Shaw KN, Morris R, and Matthews D
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- Aged, Aged, 80 and over, Female, Humans, Male, Neuropsychological Tests, Pilot Projects, Alzheimer Disease psychology, Cognition physiology, Exercise
- Abstract
Objective: To explore the effect of a non-aerobic movement based activity on cognition in people with Alzheimer's type dementia (AD)., Methods: The sample consisted of 27 patients fulfilling the AD ICD-10 diagnostic criteria. The patient sample was randomly divided into two groups: The Exercise Group received 6 weeks movement training and comprised 15 participants with a mean age of 70.5 years (SD: 8). Control Group participated in a standard care group, which served as a control intervention, and consisted of 12 patients with an average age of 75.7 years (SD: 6.90). Cognitive functions were assessed using six computerised tests from the CANTAB, pre and post training. Data were analysed using t-tests. The false discovery rate (FDR) for multiple comparisons as well as Cohen's d effect size was used to assess the significant effects., Results: Significant improvements in sustained attention, visual memory and a trend in working memory were found in the Exercise Group compared to Control Group after the 6 weeks training. In addition, after 6 weeks the Control Group deteriorated significantly in attention, while the AD patients who undertook the physical exercise showed a discrete improvement., Conclusions: The present study shows that a short course of non-aerobic movement based exercise is already effective at least in some aspects of cognitive functioning in patients with AD. Although the present study is a pilot study with small samples, nevertheless, the results are promising for the further investigation and development of non-aerobic movement programmes., (Copyright © 2010 John Wiley & Sons, Ltd.)
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- 2011
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14. Negative mood affects brain processing of visceral sensation.
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Coen SJ, Yágüez L, Aziz Q, Mitterschiffthaler MT, Brammer M, Williams SC, and Gregory LJ
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- Adult, Awareness, Brain pathology, Brain Mapping methods, Catheterization, Cerebral Cortex physiopathology, Cerebrum physiopathology, Gyrus Cinguli physiopathology, Humans, Magnetic Resonance Imaging, Male, Music, Pain pathology, Pain psychology, Pain Measurement, Pressure, Young Adult, Affect, Brain physiopathology, Enteric Nervous System metabolism, Esophagus innervation, Mechanotransduction, Cellular, Pain physiopathology, Perception, Sensory Receptor Cells metabolism
- Abstract
Background & Aims: A link between negative emotional state and abnormal visceral sensation has been frequently reported. However, the influence of negative emotion on brain processing of painful visceral sensations has not been investigated. We used functional magnetic resonance imaging (fMRI) and negative emotional stimuli to investigate the effects of negative emotion on brain processing of esophageal sensation., Methods: Twelve healthy male volunteers (age range, 21-32 years) participated in the study. Negative emotion was induced using emotionally valent music. fMRI images were acquired during 2 experimental runs; throughout these, volunteers received randomized nonpainful and painful distentions to the esophagus during neutral and negative emotion. Subjective perception of each stimulus was acquired, as were mood ratings., Results: Sadness ratings increased significantly following negative mood induction (P < .01). There was no significant effect of emotion on subjective perception of painful and nonpainful stimulation (P > .05). Following painful stimulation, brain activity increased in the right hemisphere during negative emotion and was localized to the anterior cingulate cortex (ACC; BA24/32), anterior insula, and inferior frontal gyrus. Following nonpainful stimulation during negative emotion, brain activity increased in the right anterior insula and ACC (BA24 and 32)., Conclusions: This study provides new information about the influence of negative affect on central processing of visceral pain. Evidence of right hemispheric dominance during negative emotion indicates this hemisphere is predominately associated with sympathetic activity (arousal, negative affect) and that the right insula and right ACC are integral to subjective awareness of emotion through interoception.
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- 2009
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15. Effects of attention on visceral stimulus intensity encoding in the male human brain.
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Coen SJ, Aziz Q, Yágüez L, Brammer M, Williams SC, and Gregory LJ
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- Adult, Brain Mapping methods, Humans, Magnetic Resonance Imaging methods, Male, Pain Measurement, Physical Stimulation, Reference Values, Somatosensory Cortex physiopathology, Young Adult, Attention physiology, Brain physiopathology, Esophagus innervation, Pain physiopathology
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Background & Aims: Hypervigilance is considered important in pain perception in functional gastrointestinal disorders. Nonetheless, a comprehensive assessment of the influence of attention on brain processing of visceral sensation has not been performed. We investigated the effects of attention on esophageal pain perception and brain activity., Methods: Twelve healthy male volunteers (age range, 21-32 years) underwent 4 functional magnetic resonance imaging scans incorporating 4 levels of esophageal stimulation (ES), ranging from nonpainful to painful, during which they completed a task aimed at distracting them from the esophageal stimulus. The volunteers were then scanned a fifth time, during painful stimulation without distraction., Results: Following ES during distraction, there was a significant linear trend (P < .05) in which the intensity of cerebral activation in the primary somatosensory cortex (SI) (bilateral) and left mid-anterior cingulate cortex (ACC) increased with stimulation intensity. When pain was delivered during distraction, there was a significant reduction in pain ratings, accompanied by significant decreases (P < .05) in brain activity in the right ACC and right prefrontal cortex. There was no effect of distraction on SI activity (P < .05)., Conclusions: Our results suggest that the SI is involved in processing sensory-discriminative aspects of visceral sensation. In contrast, activity in the mid-ACC suggests that this region is multifunctional because it appears to be involved in sensory and cognitive appraisal of visceral pain; the right prefrontal cortex seems to be involved in only cognitive responses to pain.
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- 2008
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16. Reproducibility of human brain activity evoked by esophageal stimulation using functional magnetic resonance imaging.
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Coen SJ, Gregory LJ, Yágüez L, Amaro E Jr, Brammer M, Williams SC, and Aziz Q
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- Adult, Catheterization, Female, Humans, Male, Pain, Pain Measurement, Reproducibility of Results, Sensory Thresholds, Brain physiology, Esophagus physiology, Magnetic Resonance Imaging
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Functional MRI is a popular tool for investigating central processing of visceral pain in healthy and clinical populations. Despite this, the reproducibility of the neural correlates of visceral sensation by use of functional MRI remains unclear. The aim of the present study was to address this issue. Seven healthy right-handed volunteers participated in the study. Blood oxygen level-dependent contrast images were acquired at 1.5 T while subjects received nonpainful and painful phasic balloon distensions ("on-off" block design, 10 stimuli per "on" period, 0.3 Hz) to the distal esophagus. This procedure was repeated on two further occasions to investigate reproducibility. Painful stimulation resulted in highly reproducible activation over three scanning sessions in the anterior insula, primary somatosensory cortex, and anterior cingulate cortex. A significant decrease in strength of activation occurred from session 1 to session 3 in the anterior cingulate cortex, primary somatosensory cortex, and supplementary motor cortex, which may be explained by an analogous decrease in pain ratings. Nonpainful stimulation activated similar brain regions to painful stimulation, but with greater variability in signal strength and regions of activation between scans. Painful stimulation of the esophagus produces robust activation in many brain regions. A decrease in subjective perception of pain and brain activity from the first to the final scan suggests that serial brain imaging studies may be affected by habituation. These findings indicate that for brain imaging studies that require serial scanning, development of experimental paradigms that control for the effect of habituation is necessary.
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- 2007
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17. An fMRI study of verbal self-monitoring: neural correlates of auditory verbal feedback.
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Fu CH, Vythelingum GN, Brammer MJ, Williams SC, Amaro E Jr, Andrew CM, Yágüez L, van Haren NE, Matsumoto K, and McGuire PK
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- Adult, Brain Mapping, Humans, Male, Statistics as Topic, Verbal Learning physiology, Auditory Perception physiology, Evoked Potentials physiology, Feedback physiology, Magnetic Resonance Imaging, Speech physiology, Speech Perception physiology, Temporal Lobe physiology
- Abstract
The ability to recognize one's own inner speech is essential for a sense of self. The verbal self-monitoring model proposes that this process entails a communication from neural regions involved in speech production to areas of speech perception. According to the model, if the expected verbal feedback matches the perceived feedback, then there would be no change in activation in the lateral temporal cortices. We investigated the neural correlates of verbal self-monitoring in a functional magnetic resonance (fMRI) study. Thirteen healthy male volunteers read aloud presented adjectives and heard their auditory feedback which was experimentally modified. Decisions about the source of the feedback were made with a button-press response. We used a 'clustered' fMRI acquisition sequence, consisting of periods of relative silence in which subjects could speak aloud and hear the feedback in the absence of scanner noise, and an event-related design which allowed separate analysis of trials associated with correct attributions and misattributions. Subjects made more misattribution responses when the feedback was a distorted version of their voice. This condition showed increased superior temporal activation relative to the conditions of hearing their own voice undistorted and hearing another person's voice. Furthermore, correct attributions during this condition were associated with greater temporal activation than misattributions. These findings support the self-monitoring model as mismatches between expected and actual auditory feedback were associated with greater temporal activation.
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- 2006
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18. Brain response to visceral aversive conditioning: a functional magnetic resonance imaging study.
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Yágüez L, Coen S, Gregory LJ, Amaro E Jr, Altman C, Brammer MJ, Bullmore ET, Williams SC, and Aziz Q
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- Adult, Conditioning, Classical, Extinction, Psychological, Female, Humans, Magnetic Resonance Imaging, Male, Reinforcement, Psychology, Viscera innervation, Avoidance Learning, Brain pathology, Brain physiology, Pain physiopathology
- Abstract
Background & Aims: Brain-imaging studies to date have confounded visceral pain perception with anticipation. We used functional magnetic resonance imaging of the human brain to study the neuroanatomic network involved in aversive conditioning of visceral pain and, thus, anticipation., Methods: Eight healthy volunteers (5 male) participated in the study. We used a classic conditioning paradigm in which 3 neutral stimuli (differently colored circles) that acted as conditioned stimuli were paired with painful esophageal distention, air puff to the wrist, or nothing, which acted as unconditioned stimuli. Neural activity was measured during learning, anticipation (pairing only 50% of conditioned stimuli with their unconditioned stimuli), and extinction (unpaired conditioned stimuli) phases. For magnetic resonance imaging, axial slices depicting blood oxygen level-dependent contrast were acquired with a 1.5-T system., Results: Neural responses during the learning phase included areas commonly associated with visceral pain (anterior cingulate cortex, insula, and primary and secondary somatosensory cortices) and innocuous somatosensory perception (primary and secondary somatosensory cortices and insula). During the anticipation and extinction phases of aversive stimulation, brain activity resembled that seen during actual painful esophageal stimulation. In contrast, anticipation and extinction of the innocuous somatic stimulus failed to show that effect., Conclusions: We have shown that actual and anticipated visceral pain elicit similar cortical responses. These results have implications for the design and interpretation of brain-imaging studies of visceral pain. They not only contribute to our understanding of the processing of visceral pain, but also have clinical implications for the management of chronic pain states.
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- 2005
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19. Hemispheric dissociation of visual-pattern processing and visual rotation.
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Suchan B, Yágüez L, Wunderlich G, Canavan AG, Herzog H, Tellmann L, Hömberg V, and Seitz RJ
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- Adult, Cerebrovascular Circulation, Female, Humans, Male, Memory physiology, Nerve Net physiology, Photic Stimulation, Psychomotor Performance physiology, Reaction Time physiology, Rotation, Tomography, Emission-Computed, Brain diagnostic imaging, Brain physiology, Functional Laterality physiology, Imagination physiology, Pattern Recognition, Visual physiology
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We aimed at investigating whether on-line and delayed visual pattern processing activated different areas in human prefrontal and parietal cortex. For this purpose we measured the regional cerebral blood flow (rCBF) during simultaneous and successive visual matrix processing in 10 right-handed subjects. Delayed matching to sample activated predominantly left hemispheric ventrolateral prefrontal cortex, Broca's area and parts of the parietal cortex. In contrast, visuospatial matrix rotation showed activation of the right dorsolateral prefrontal cortex and parietal lobe. The present results suggest a hemispheric dissociation of fronto-parietal circuits with a left dominance for visual pattern processing like storage and a right dominance for visuospatial processing., (Copyright 2002 Elsevier Science B.V.)
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- 2002
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20. Neural correlates of visuospatial imagery.
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Suchan B, Yágüez L, Wunderlich G, Canavan AG, Herzog H, Tellmann L, Hömberg V, and Seitz RJ
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- Adult, Female, Frontal Lobe blood supply, Frontal Lobe diagnostic imaging, Frontal Lobe physiology, Humans, Male, Parietal Lobe blood supply, Parietal Lobe diagnostic imaging, Parietal Lobe physiology, Reaction Time physiology, Tomography, Emission-Computed, Brain diagnostic imaging, Cerebrovascular Circulation physiology, Imagination physiology
- Abstract
We studied changes in regional cerebral blood flow (rCBF) in 10 healthy right-handed subjects during a visuospatial imagery task. The subject's task consisted of drawing imagined lines connecting encircled numbers in ascending order and estimating the number of lines crossing. Compared with a control task in which there were no crossed lines, there were significant rCBF increases in the cingulate gyrus, the adjacent superior frontal gyrus and in the left inferior parietal cortex. The rCBF changes of the latter area correlated with task performance time. Since these activation areas are close to those in imagery of movement trajectories, we concluded that they appear to be a subsystem for processing mental visuospatial images.
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- 2002
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21. Motor learning by imagery is differentially affected in Parkinson's and Huntington's diseases.
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Yágüez L, Canavan AG, Lange HW, and Hömberg V
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- Adult, Aged, Aged, 80 and over, Basal Ganglia physiopathology, Caudate Nucleus physiopathology, Dopamine physiology, Female, Humans, Huntington Disease diagnosis, Male, Middle Aged, Neuropsychological Tests, Parkinson Disease diagnosis, Practice, Psychological, Huntington Disease physiopathology, Imagination physiology, Mental Recall physiology, Parkinson Disease physiopathology, Psychomotor Performance physiology
- Abstract
Studies of motor imagery and motor learning have thus far been concerned only with its effects on healthy subjects. Therefore, in order to investigate the possible involvement of the basal ganglia, the effectiveness of motor imagery in the acquisition of motor constants in a graphomotor trajectorial learning task was examined in 11 non-demented mildly affected Huntington's disease (HD) patients and 12 non-demented Parkinson's disease (PD) patients. The patients received, after baseline, 10 min of motor imagery training, followed by a motor practice phase. Additionally, a test battery for visual imagery abilities was administered in order to investigate possible relations between visual and motor imagery. The results showed that imagery training alone enabled the HD patients to achieve a significant approach to movement isochrony, whereas the PD patients showed no marked improvements, either with motor imagery or with motor practice. Furthermore, the PD patients had more difficulties than the HD patients in solving the visual imagery tasks. Subsequent correlational analysis revealed significant relationships between the degree of caudate atrophy in the HD patients and their performance in the visual imagery tasks. However, there were no substantial correlations between the performance on the visual imagery tasks and the improvement of motor performance through motor imagery, which indicates that visual and motor imagery are independent processes. It is suggested that the dopaminergic input to the basal ganglia plays an important role in the translation of motor representations into motor performance, whereas the caudate nucleus atrophy of the HD patients does not seem to affect motor imagery, but only the visual imagery process. Furthermore, the deficits found in PD patients might also be related to their limited attentional resources and difficulties in employing predictive motor strategies.
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- 1999
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22. Representations of graphomotor trajectories in the human parietal cortex: evidence for controlled processing and automatic performance.
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Seitz RJ, Canavan AG, Yágüez L, Herzog H, Tellmann L, Knorr U, Huang Y, and Hömberg V
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- Adult, Female, Humans, Kinesthesis physiology, Male, Neural Pathways physiology, Parietal Lobe diagnostic imaging, Tomography, Emission-Computed, Brain Mapping methods, Mental Processes physiology, Motor Activity physiology, Parietal Lobe physiology, Psychomotor Performance physiology, Writing
- Abstract
The aim of this study was to identify the cerebral areas activated during kinematic processing of movement trajectories. We measured regional cerebral blood flow (rCBF) during learning, performance and imagery of right-hand writing in eight right-handed volunteers. Compared with viewing the writing space, increases in rCBF were observed in the left motor, premotor and frontomesial cortex, and in the right anterior cerebellum in all movement conditions, and the increases were related to mean tangential writing velocity. No rCBF increases occurred in these areas during imagery. Early learning of new ideomotor trajectories and deliberately exact writing of letters both induced rCBF increases in the cortex lining the right intraparietal sulcus. In contrast, during fast writing of overlearned trajectories and in the later phase of learning new ideograms the rCBF increased bilaterally in the posterior parietal cortex. Imagery of ideograms that had not been practised previously activated the anterior and posterior parietal areas simultaneously. Our results provide evidence suggesting that the kinematic representations of graphomotor trajectories are multiply represented in the human parietal cortex. It is concluded that different parietal subsystems may subserve attentive sensory movement control and whole-field visuospatial processing during automatic performance.
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- 1997
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23. Successive roles of the cerebellum and premotor cortices in trajectorial learning.
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Seitz RJ, Canavan AG, Yágüez L, Herzog H, Tellmann L, Knorr U, Huang Y, and Hömberg V
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- Cerebrovascular Circulation, Functional Laterality, Handwriting, Humans, Motor Activity physiology, Motor Cortex diagnostic imaging, Time Factors, Tomography, Emission-Computed, Cerebellum physiology, Learning physiology, Motor Cortex physiology
- Abstract
The structures of the human brain engaged during learning of unilateral trajectorial hand movements were mapped by measurements of regional cerebral blood flow. Trajectorial movement velocity accelerated moderately after short-term training p < 0.025 and increased further after long-term training p < 0.01. During the early phase of learning there was a significant activation p < 0.001 of the ipsilateral dentate nucleus. By contrast, after overlearning the premotor cortical areas in both cerebral hemispheres were maximally activated p < 0.001, while the dentate nucleus was no longer activated. It is suggested that learning of new movement trajectories involves the cerebellum, while overlearned trajectorial movements engage the premotor cortex.
- Published
- 1994
- Full Text
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