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Background: Whereas the motor dysfunction in Parkinson's disease (PD) has been related to deficits in basal ganglia (BG) structures, neural correlates of cognitive changes remain to be fully defined. This study tested the hypothesis that cognitive changes in non-demented PD may be related to cortical gray matter (GM) loss., Methods: High-resolution T1-weighted magnetic resonance images of the brain and comprehensive cognitive function tests were acquired in 40 right-handed, non-demented PD subjects and 40 matched controls. GM changes were assessed using voxel-based morphometry (VBM) in FSL. VBM and cognitive results were compared between PD and controls, and correlation analyses were performed between those brain areas and cognitive domains that showed significant group differences., Results: PD patients demonstrated significant GM reduction localized predominantly in frontal and parieto-occipital regions. Patients also showed reduced performance in fine motor speed and set-shifting compared to controls. Fine motor speed and set-shifting were associated with GM volume in the frontal cortex in controls, whereas these domains were associated primarily with occipital GM regions in PD patients., Conclusions: Non-demented PD subjects demonstrate cortical structural changes in frontal and parieto-occipital regions compared to controls. The association between typically recognized "frontal lobe" function and occipital lobe volume suggested a compensatory role of occipital lobe to primary fronto-striatal pathology in PD. Further longitudinal study of these changing structure-function relationships is needed to understand the neural bases of symptom progression in PD., (Copyright © 2013 Elsevier Ltd. All rights reserved.)

The potential contribution of social science research to close the gap of knowledge between cognitive neuroscience and educational research has been underappreciated. Despite their virtual absence in the interdisciplinary dialog of neuroscience, sociology of education and related study of the cultural impact of formal education have generated research relevant to an understanding of how the social environment, such as widespread schooling, co-evolves with, and enhances neurocognitive development. Two clusters of isolated research literatures are synthesized that taken together anticipates a dynamic integration of neuroscience and education. The first cluster is on the social construction of cognition through formal education in contemporary society, including the effects of schooling on neurological and cognitive development; the demographic expansion of exposure to the developmental influence of schooling; and education's cultural impact on the meaning of the learning experience and reinforcement of cognition as the key human capability across ever more key institutions in postindustrial society. The second cluster turns the issue around by examining current investigations from neuroscience that support neurological hypotheses about the causes behind the schooling effect on neurocognitive development. We propose that further integration of these literatures will provide a more ecologically valid context in which to investigate the evolving functional architecture of the contemporary brain., (Copyright © 2011 Elsevier Ltd. All rights reserved.)

We investigated the occurrence of goal-directed motivational change in the form of apathy in patients with frontotemporal dementia (FTD), particularly those with behavioral variant social and executive deficits (bvFTD). Standardized behavioral inventory was employed to survey and compare apathy ratings from patients and caregivers. In cases of bvFTD, apathy ratings were further related to measures of social cognition, executive function, and atrophy on brain MRI. Results indicated that caregivers rated bvFTD patients as having significantly elevated apathy scores though patient self-ratings were normal. Caregiver and self-ratings of FTD samples with progressive nonfluent aphasia and semantic dementia did not differ from healthy controls and their informants. In the bvFTD sample, caregiver apathy scores were not correlated with general cognitive screening or depression scores, but were significantly correlated with social cognition and executive function measures. Voxel-based morphometry revealed that apathy ratings in bvFTD were related to prominent atrophy in the right caudate (including the ventral striatum), the right temporo-parietal junction, right posterior inferior and middle temporal gyri, and left frontal operculum- anterior insula region. Findings suggest that bvFTD is associated with a significant breakdown in goal-directed motivated behavior involving disruption of cortical-basal ganglia circuits that is also related to social and executive function deficits.

The authors investigated aspects of interpersonal sensitivity and perspective-taking in relation to empathy, social cognitions, and executive functioning in 26 frontotemporal dementia (FTD) patients. Behavioral-variant FTD (bvFTD) patients were significantly impaired on caregiver assessments of empathy, although self-ratings were normal. Progressive nonfluent aphasia and semantic-dementia samples were rarely abnormal. In bvFTD, empathy ratings were found to be correlated with social cognition and executive functioning measures, but not depression. Voxel-based morphometry revealed that reduced empathic perspective-taking was related to bifrontal and left anterior temporal atrophy, whereas empathic emotions were related to right medial frontal atrophy. Findings suggest that bvFTD causes multiple types of breakdown in empathy, social cognition, and executive resources, mediated by frontal and temporal disease.

To investigate maturational plasticity of fluid cognition systems, functional brain imaging was undertaken in healthy 8-19 year old participants while completing visuospatial relational reasoning problems similar to Raven's matrices and current elementary grade math textbooks. Analyses revealed that visuospatial relational reasoning across this developmental age range recruited activations in the superior parietal cortices most prominently, the dorsolateral prefrontal, occipital-temporal, and premotor/supplementary cortices, the basal ganglia, and insula. There were comparable activity volumes in left and right hemispheres for nearly all of these regions. Regression analyses indicated increasing activity predominantly in the superior parietal lobes with developmental age. In contrast, multiple anterior neural systems showed significantly less activity with age, including dorsolateral and ventrolateral prefrontal, paracentral, and insula cortices bilaterally, basal ganglia, and particularly large clusters in the midline anterior cingulate/medial frontal cortex, left middle cingulate/supplementary motor cortex, left insula-putamen, and left caudate. Findings suggest that neuromaturational changes associated with visuospatial relational reasoning shift from a more widespread fronto-cingulate-striatal pattern in childhood to predominant parieto-frontal activation pattern in late adolescence.

Purpose: To analyze the effects of cognition on function and to explore the potential of aerobic exercise for promoting cognitive and functional capacities., Design: Integrative review of literature., Methods: Studies were selected based on an extensive search of electronic databases and manual cross-referencing for 1980 to 2006, using the combination of key words: Alzheimer's disease (AD), dementia, or cognitive impairment with function or activities of daily living., Findings: Three broad themes were identified from the literature analysis. First, global cognition has mainly been used to examine the effect of cognition on function, indicating an assumption that functional decline progresses in a hierarchical manner in AD. Second, specific cognitive domains affect functional decline in different ways. Executive functioning might have more effect on function than does memory. Third, aerobic exercise might promote cognitive and functional capacities in people with AD by modifying neuropathological changes in the brain., Conclusions: Specific cognitive domains such as executive functioning are important for understanding function in people with AD and are potentially modifiable by aerobic exercise.

Recent investigations in cognitive neuroscience have shown that ordinary human behavior is guided by emotions that are uniquely human in their experiential and interpersonal aspects. These "moral emotions" contribute importantly to human social behavior and derive from the neurobehavioral reorganization of the basic plan of emotions that pervade mammalian life. Disgust is one prototypic emotion with multiple domains that include viscerosomatic reaction patterns and subjective experiences linked to (a) the sensory properties of a class of natural stimuli, (b) a set of aversive experiences and (c) a unique mode of experiencing morality. In the current investigation, we tested the hypotheses that (a) the experience of disgust devoid of moral connotations ("pure disgust") can be subjectively and behaviorally differentiated from the experience of disgust disguised in the moral emotion of "indignation" and that (b) pure disgust and indignation may have partially overlapping neural substrates. Thirteen normal adult volunteers were investigated with functional magnetic resonance imaging as they read a series of statements depicting scenarios of pure disgust, indignation, and neutral emotion. After the scanning procedure, they assigned one basic and one moral emotion to each stimulus from an array of six basic and seven moral emotions. Results indicated that (a) emotional stimuli may evoke pure disgust with or without indignation, (b) these different aspects of the experience of disgust could be elicited by a set of written statements, and (c) pure disgust and indignation recruited both overlapping and distinct brain regions, mainly in the frontal and temporal lobes. This work underscores the importance of the prefrontal and orbitofrontal cortices in moral judgment and in the automatic attribution of morality to social events. Human disgust encompasses a variety of emotional experiences that are ingrained in frontal, temporal, and limbic networks.

BackgroundMild cognitive impairment is common in Parkinson disease (PD-MCI). However, instability in this clinical diagnosis and variability in rates of progression to dementia raises questions regarding its utility for longitudinal tracking and prediction of cognitive change in PD. We examined baseline neuropsychological test and cognitive diagnosis predictors of cognitive change in PD.MethodsPersons with PD, without dementia PD (N=138) underwent comprehensive neuropsychological assessment at baseline and were followed up to 2 years. Level II Movement Disorder Society criteria for PD-MCI and PD dementia (PDD) were applied annually. Composite global and domain cognitive z -scores were calculated based on a 10-test neuropsychological battery.ResultsBaseline diagnosis of PD-MCI was not associated with a change in global cognitive z -scores. Lower baseline attention and higher executive domain z -scores were associated with greater global cognitive z -score worsening regardless of cognitive diagnosis. Worse baseline domain z -scores in the attention and language domains were associated with progression to MCI or PDD, whereas higher baseline scores in all cognitive domains except executive function were associated with clinical and psychometric reversion to "normal" cognition.ConclusionsLower scores on cognitive tests of attention were predictive of worse global cognition over 2 years of follow-up in PD, and lower baseline attention and language scores were associated with progression to MCI or PDD. However, PD-MCI diagnosis per se was not predictive of cognitive decline over 2 years. The association between higher executive domain z -scores and greater global cognitive worsening is probably a spurious result.

BackgroundClinical monitoring of patients with Parkinson's disease (PD) for cognitive decline is an important element of care. The Montreal Cognitive Assessment (MoCA) has been proposed to be a sensitive tool for assessing cognitive impairment in PD. The aim of our study was to compare the responsiveness of the MoCA to decline in cognition to the responsiveness of the Mini Mental State Examination (MMSE) and the Scales for Outcomes of Parkinson's disease-cognition (SCOPA-Cog).MethodsPD patients without dementia were enrolled at 6 North American movement disorders centers between 2008 and 2011. Participants received annual evaluations including the MoCA, MMSE, and SCOPA-Cog followed by formal neuropsychological testing. The gold standard for change in cognition was defined as the change on the neuropsychological test scores over the annual assessments. The Reliable Change Method was used to provide an estimate of the probability that a given difference score would be obtained by chance. The sensitivity of the MoCA, MMSE, and SCOPA-Cog to change was quantified using receiver operating characteristics (ROC) curves.ResultsOne hundred seventeen patients were included in the analysis. Participants were followed at mean intervals of 11 ± 2 months for a median of 2 (maximum 5) visits. According to the reliable change index, 56 intervals of cognitive testing showed a decline in global cognition. ROC analysis of change in MoCA, MMSE, and SCOPA-Cog global scores compared to gold standard testing found an area under the curve (AUC) of 0.55 (95% CI 0.48-0.62), 0.56 (0.48-0.63), and 0.63 (0.55-0.70) respectively. There were no significant differences in the AUCs across the tests. The sensitivity of the MoCA, MMSE, and SCOPA-Cog to change at various thresholds for decline in scores reached a maximum of 71% for a cut-off of 1 point change on the SCOPA-Cog.ConclusionUsing neuropsychological testing as a gold standard comparator, the performance of the MoCA, MMSE, and SCOPA-Cog for detecting decline in non-demented PD patients over a 1-year interval is poor. This has implications for clinical practice; stable scores may not be taken as reassurance of the absence of cognitive decline.

BackgroundNumerous neuropsychological tests and test versions are used in Parkinson's disease research, but their relative capacity to detect mild cognitive deficits and their comparability across studies are unknown. The objective of this study was to identify neuropsychological tests that consistently detect cognitive decline in PD across studies.MethodsData from 30 normed neuropsychological tests across 20 international studies in up to 2908 nondemented PD patients were analyzed. A subset of 17 tests was administered to up to 1247 healthy controls. A 2-step meta-analytic approach using standardized scores compared performance in PD with normative data.ResultsPooled estimates of the differences between PD and site-specific healthy controls identified significant cognitive deficits in PD patients on 14 test scores across 5 commonly assessed cognitive domains (attention or working memory, executive, language, memory, and visuospatial abilities), but healthy control performance was statistically above average on 7 of these tests. Analyses based on published norms only, as opposed to direct assessment of healthy controls, showed high between-study variability that could not be accounted for and led to inconclusive results.ConclusionsNormed neuropsychological tests across multiple cognitive domains consistently detect cognitive deficits in PD when compared with site-specific healthy control performance, but relative PD performance was significantly affected by the inclusion and type of healthy controls versus the use of published norms only. Additional research is needed to identify a cognitive battery that can be administered in multisite international studies and that is sensitive to cognitive decline, responsive to therapeutic interventions, and superior to individual cognitive tests. © 2018 International Parkinson and Movement Disorder Society.

Background and Purpose: The circuitry underlying heterogenous cognitive profiles in Parkinson's disease (PD) remains unclear. The purpose of this study is to investigate whether structural changes in frontostriatal and limbic pathways contribute to different cognitive trajectories in PD. Methods: We obtained clinical and multimodal MRI data from 120 control and 122 PD subjects without dementia or severe motor disability. T1/T2‐weighted images estimated volume, and diffusion imaging evaluated fractional anisotropy (FA) of frontostriatal (striatum and frontostriatal white matter [FSWM]) and limbic (hippocampus and fornix) structures. Montreal Cognitive Assessment (MoCA) gauged total and domain‐specific (attention/executive and memory) cognitive function. Linear mixed‐effects models were used to compare MRI and cognitive progression over 4.5 years between controls and PD and evaluate associations between baseline MRI and cognitive changes in PD. Results: At baseline, control and PD groups were comparable, except PD participants had smaller striatal volume (p < 0.001). Longitudinally, PD showed faster decline in hippocampal volume, FSWM FA, and fornix FA (ps <.016), but not striatal volume (p =.218). Total and domain‐specific MoCA scores declined faster in PD (ps <.030). In PD, lower baseline hippocampal volume (p =.005) and fornix FA (p =.032), but not striatal volume (p =.662) or FSWM FA (p =.143), were associated with faster total MoCA decline. Baseline frontostriatal metrics of striatal volume and FSWM FA were associated with faster attention/executive decline (p <.038), whereas lower baseline hippocampal volume was associated with faster memory decline (p =.005). Conclusion: In PD, frontostriatal structural metrics are associated with attention/executive tasks, whereas limbic changes correlated with faster global cognitive decline, particularly in memory tasks. [ABSTRACT FROM AUTHOR]

Background: The presence of subjective cognitive complaints (SCC) as a predictor of cognitive impairment in Parkinson´s disease (PD) has shown conflicting results. Most previous studies only assessed complaints in the memory domain. We investigate the association of SCCs across cognitive domains with development of mild cognitive impairment (PD‐MCI) and dementia (PDD) in PD and to assess agreement between SCCs and objective cognitive impairments in this population. Methods: This is a retrospective analysis of a prospective cohort study. Participants were enrolled at six North‐American movement disorders centers. They underwent neuropsychological and non‐cognitive clinical evaluations, including the modified Neurobehavioral Inventory to elicit SCC (rated by each patient and independently by their close contact (CC)). Associations between SCCs and development of future cognitive impairment were assessed. Agreement between SCCs and objective impairment within the same domain was also calculated. Results: Of 138 included PD patients, 42% fulfilled criteria for PD‐MCI. None of the NBI items predicted development of cognitive impairment after one and two years in PD with normal cognition. In PD‐MCI patients, SCCs related to attention predicted dementia at year one. CC ratings of SCCs related to memory and language problems predicted PDD in PD‐MCI patients. According to CC reported patients' complaints, there was a significant agreement between SCCs and objective cognitive test scores on attention. Conclusions: Eliciting SCCs including cognitive domains other than memory is crucial for a complete evaluation, including both patient and CC report. Memory, language, and especially attention SCCs in PD‐MCI may predict progression to dementia. [ABSTRACT FROM AUTHOR]

Plasma low density lipoprotein (LDL) cholesterol has been associated both with risk of Parkinson's disease (PD) and with age-related changes in cognitive function. This prospective study examined the relationship between baseline plasma LDL-cholesterol and cognitive changes in PD and matched Controls. Fasting plasma LDL-cholesterol levels were obtained at baseline from 64 non-demented PD subjects (62.7 ± 7.9 y) and 64 Controls (61.3 ± 6.8 y). Subjects underwent comprehensive neuropsychological testing at baseline, 18-, and 36-months. Linear mixed-effects modeling was used to assess the relationships between baseline LDL-cholesterol levels and longitudinal cognitive changes. At baseline, PD patients had lower scores of fine motor (p<0.0001), executive set shifting (p=0.018), and mental processing speed (p=0.049) compared to Controls. Longitudinally, Controls demonstrated improved fine motor and memory test scores (p=0.044, and p=0.003), whereas PD patients demonstrated significantly accelerated loss in fine motor skill (p=0.002) compared to Controls. Within the PD group, however, higher LDL-cholesterol levels were associated with improved executive set shifting (β=0.003, p<0.001) and fine motor scores (β=0.002, p=0.030) over time. These associations were absent in Controls (p>0.7). The cholesterol - executive set shifting association differed significantly between PDs and Controls (interaction p=0.005), whereas the cholesterol - fine motor association difference did not reach significance (interaction, p=0.104). In summary, higher plasma LDL-cholesterol levels were associated with better executive function and fine motor performance over time in PD, both of which may reflect an effect on nigrostriatal mediation. Confirmation of these results and elucidation of involved mechanisms are warranted, and might lead to feasible therapeutic strategies. [ABSTRACT FROM AUTHOR]

Abstract: Spatial bias demonstrated in tasks such as line-bisection may stem from perceptual–attentional (PA) “where” and motor-intentional (MI) “aiming” influences. We tested normal participants’ line bisection performance in the presence of an asymmetric visual distracter with a video apparatus designed to dissociate PA from MI bias. An experimenter stood as a distractor to the left or right of a video monitor positioned in either near or far space, where participants viewed lines and a laser point they directed under (1) natural and (2) mirror-reversed conditions. Each trial started with the pointer positioned at either the top left or top right corner of the screen, and alternated thereafter. Data analysis indicated that participants made primarily PA leftward errors in near space, but not in far space. Furthermore, PA, but not MI, bias increased bilaterally in the direction of distraction. In contrast, MI, but not PA, bias was shifted bilaterally in the direction of startside. Results support the conclusion that a primarily PA left sided bias in near space is consistent with right hemisphere spatial attentional dominance. A bottom–up visual distractor specifically affected PA “where” spatial bias while top–down motor cuing influenced MI “aiming” bias. [Copyright &y& Elsevier]

Impairments of social behavior after cerebral damage are often problematic and difficult to assess and manage, with few models addressing evaluation, treatment options and prognosis. Recent studies suggest that a fundamental mechanism of social behavior disturbed by acquired cerebral damage is empathy. Empathy refers to the cognitive and emotional processes that bind people together in various kinds of relationships that permit sharing of experiences as well as understanding of others. Empathic changes are particularly evident after focal prefrontal cortex damage and closed head injury in adults, though early frontal lobe damage is also associated with poor empathic and social development. Although alterations in empathy have been studied in only a handful of neurologic samples thus far, it may be an important outcome variable of brain injury, particularly in patients’ adjustment to family, community and vocational settings. Treatment possibilities are presented, though more comprehensive research is needed. [ABSTRACT FROM AUTHOR]

Parkinson's disease (PD) is characterized by dopaminergic cell loss and reduced striatal volume. Prior studies have demonstrated striatal involvement in access to lexical-semantic knowledge and damage to this structure may be evident in the lexical properties of responses. Semantic fluency task responses from early stage, non-demented PD participants with right (PD-R) or left (PD-L) lateralizing symptoms were compared to matched controls on lexical properties (word frequency, age of acquisition) and correlated with striatal volumes segmented from T1-weighted brain MR images. PD-R participants produced semantic fluency responses of a lower age of acquisition than PD-L and control participants (p < 0.05). PD-R age of acquisition responses correlated positively with putamen volume (p < 0.05), while age of acquisition of responses correlated negatively with caudate volume in controls (p < 0.05). Findings provide evidence for a role of the striatum in lexical-semantic access and qualitative changes in lexical access in select PD patients. [ABSTRACT FROM AUTHOR]

Presents comments on a study regarding the distinctions between two kinds of modulation upon comparing between the origin and clinical appearance of Parkinson's disease and catatonia. Overview of cognitive-oriented behavioral qualifiers; Comparison of the symptoms of catatonia with manic-depressive disorders; Anatomical correlates of catatonia in line with patients with focal brain injury.

Background Parkinson's disease (PD) is a neurodegenerative disorder that generally begins with asymmetric motor symptoms that persist over time. This suggests that the dysfunction in the nigrostriatal motor circuit may be lateralized. The present study examined whether the asymmetric motor presentation is associated with hemisphere-specific cognitive decline and lateralized gray matter volume loss. Methods Data from comprehensive cognitive tests that measured visuospatial and verbal functions and high-resolution T1-weighted magnetic resonance images of the brain were acquired in 23 PD subjects with left-side motor symptom onset (PDL), 23 PD subjects with right-side onset (PDR), and 23 matched Controls. GM volume differences were assessed using voxel-based morphometry (VBM). Cognitive results and VBM were compared among the three groups, and correlation analyses were performed between those cognitive domains and brain areas that showed significant differences. Results PDL subjects had lower performance on visuospatial memory tasks compared to PDR. Furthermore, PDL subjects experienced lateralized GM loss, which was localized predominantly in the right hemisphere contralateral to the side of motor symptom onset. Visuospatial memory performance in PDL was correlated with GM loss in the right middle frontal gyrus and precuneus. Conclusion These data suggest that the onset of asymmetric motor symptoms in PD may be associated with hemisphere-specific memory decline and lateralized GM loss, particularly in PDL. This study underscores the importance of classifying PD subgroups based on the side of motor symptom onset for clinical care and research to optimize cognitive outcomes. [ABSTRACT FROM AUTHOR]

Abstract: Objectives: To investigate the effects of light therapy on cognition, depression, sleep, and circadian rhythms in a general, nonselected population of seniors living in a long term care facility. Design: A double-blind, placebo-controlled trial. Setting: The experiment took place at a long term care facility in Pennsylvania. Participants: Study participants (15 treatment, 13 placebo) were residents receiving either personal care or skilled nursing care. Intervention: Treatment consisted of approximately 400 lux of blue light administered for 30 minutes per day, Monday through Friday, for 4 weeks. The placebo was approximately 75 lux of red light generated from the same device. Measurements: Behavioral assessments were made using the MicroCog Assessment of Cognitive Functioning, Geriatric Depression Scale, and Profile of Mood States. Daytime sleepiness was evaluated using the Epworth Sleepiness Scale. Results: Three of the 4 composite scores from the MicroCog as well as the mean Tension/Anxiety score from the Profile of Mood States showed a significant treatment versus placebo effect. Conclusion: Blue light treatment led to significant cognitive improvements compared with placebo red light and may be a promising environmental intervention to reduce cognitive symptoms in elderly, long-term care residents. [Copyright &y& Elsevier]