Antisaccades in Parkinson’s Disease: A Meta-Analysis

Neuropsychology Review - The usefulness of eye-tracking tasks as potential biomarkers for motor or cognitive disease burden in Parkinson’s disease (PD) has been subject of debate for many...     

Meta-Analysis of Cognition in Parkinson’s Disease Mild Cognitive Impairment and Dementia Progression

Neuropsychology Review - Mild cognitive changes, including executive dysfunction, are seen in Parkinson’s Disease (PD). Approximately 30% of individuals with PD develop Parkinson’s...     

Detectable Neuropsychological Differences in Early Preclinical Alzheimer’s Disease: A Meta-Analysis

The development of methods for in vivo detection of cerebral beta amyloid retention and tau accumulation have been increasingly useful in characterizing preclinical Alzheimer’s disease (AD). While the association between these biomarkers and eventual AD has been demonstrated among cognitively intact older adults, the link between biomarkers and neurocognitive ability remains unclear. We conducted a meta-analysis to test the hypothesis that cognitively intact older adults would show statistically discernable differences in neuropsychological performance by amyloid status (amyloid negative = A-, amyloid positive = A+). We secondarily hypothesized a third group characterized by either CSF tau pathology or neurodegeneration, in addition to amyloidosis (A+/N+ or Stage 2), would show lower neuropsychology scores than the amyloid positive group (A+/N- or Stage 1) when compared to the amyloid negative group. Pubmed, PsychINFO, and other sources were searched for relevant articles, yielding 775 total sources. After review for inclusion/exclusion criteria, duplicates, and risk of bias, 61 studies were utilized in the final meta-analysis. Results showed A+ was associated with poorer performance in the domains of global cognitive function, memory, language, visuospatial ability, processing speed, and attention/working memory/executive functions when compared to A-. A+/N+ showed lower performances on memory measures when compared to A+/N- in secondary analyses based on a smaller subset of studies. Results support the notion that neuropsychological measures are sensitive to different stages of preclinical AD among cognitively intact older adults. Further research is needed to determine what constitutes meaningful differences in neuropsychological performance among cognitively intact older adults.     

Impulse Control Disorders in Parkinson’s Disease: A Psychosocial Perspective

Parkinson's disease (PD) is a progressive neurodegenerative disease primarily characterised by motor symptoms. However, another feature of PD which is receiving increasing attention is the phenomenon of impulse control disorders (ICDs), such as pathological gambling. To date, research into ICDs in PD has centred on a biomedical model of cause, related to the effects of dopamine replacement therapy. However, there are several areas of discrepancy in the current biomedical account of ICDs in PD. In addition, we argue that social and psychological factors also need to be considered to achieve a more complete understanding of the phenomenon. We present a novel conceptual model which combines biomedical and psychosocial factors in the genesis of ICDs in PD and use the model to identify a number of potential treatment intervention points and to highlight important outstanding questions concerning the inter-relationship between psychosocial and biomedical factors in the genesis of ICDs in PD.     

Cognitive-behavioral Strategies for Parkinson’s Disease: A Report of Three Cases

Three patients diagnosed with idiopathic Parkinson’s disease (PD) were treated with cognitive-behavioral therapy (CBT): a 43-year-old woman suffering from depression and social anxiety, a 45-year-old man with sexual problems and maladaptive coping strategies, and a 78-year-old man with freezing of gait. On the basis of functional analyses, interventions were selected, including cognitive methods, social skills training, paradoxical instructions and strategies to improve management of freezing. The interventions were related to improved adaptation to motor impairments and better ability to cope with the disease. These case presentations suggest that CBT can improve quality of life in PD by modifying maladaptive cognitive, emotional and behavioral reactions to the disease and its symptoms.     

Sleep Disorders and Cognitive Dysfunctions in Parkinson’s Disease: A Meta-Analytic Study

Neuropsychology Review - A relationship between sleep disorders and cognitive dysfunctions was reported in Parkinson’s Disease (PD), however, some studies did not confirm the link. A...     

Telephone-Administered Cognitive Behavioral Therapy: A Case Study of Anxiety and Depression in Parkinson’s Disease

Parkinson’s disease (PD) is a chronic medical illness with a high incidence of psychiatric comorbidity, specifically depression and anxiety. Research on treatment of such psychiatric complications is scarce. Non-pharmaceutical treatment options are especially attractive. Cognitive behavioral therapy (CBT) is a psychotherapeutic treatment option that has been successful in other chronically medically ill populations with comorbid depression and anxiety. The current research had two aims. The first was to pilot the feasibility of screening and identifying PD patients with symptoms of anxiety and depression in a specialized outpatient clinic. The second aim was to pilot the feasibility of telephone-administered CBT for the treatment of depression and anxiety in persons with PD, which was done through a case series comparing telephone-administered CBT to a Support strategy. A fairly large portion (67.5%) of patients screened in the outpatient clinic were identified as having symptoms of anxiety and/or depression. Results also indicated that CBT delivered via the telephone is a useful approach for targeting psychiatric symptoms in this population. A case example is given to illustrate the clinical considerations associated with delivering therapy via telephone to persons with PD. This study was conducted at the Michael E. DeBakey Veterans Affairs Medical Center, Houston, TX. The first author was previously affiliated with the Houston Center for Quality of Care and Utilization Studies.     

Eye-Hand Coordination in Aging and in Parkinson’s Disease

Aiming movements to defined target positions were performed as fast and as accurately as possible by younger and older subjects and by patients in the early stages of Parkinson's disease (PD). Movement time and accuracy were tested in two conditions: with and without a centre cue. Older subjects exhibited slower movement time relative to the younger subjects only when the centre cue was present suggesting inefficient feedback processing. The performance of patients with PD was found to be as precise as that of older subjects. The movements of PD subjects, however, were slower in both conditions. Finally, the performance of subjects improved over trials. The data suggest that there is no difference in the nature of the control processes used by older and early-stage PD subjects, but that there is a reduction in the speed of these processes in PD.     

Fogelin’s Theory of Deep Disagreements: A Relativistic Reading

In “The Logic of Deep Disagreements,” Robert Fogelin claims that parties to a deep disagreement lack the common ground needed for arguments to work, making the disagreement impervious to rational resolution. Although Fogelin’s article received numerous responses, there has been no attempt to elucidate the epistemological theory behind Fogelin’s theses. In this article, I examine Fogelin’s theory of deep disagreements in light of his broader philosophy. The picture that emerges is that of relativism of distance, à la Bernard Williams. By interpreting Fogelin’s theory as relativism of distance, it avoids some of the critiques that have been raised against it.     

Sensorimotor Impairment of Speech and Hand Movement Timing Processing in Parkinson’s Disease

Models of motor control have highlighted the role of temporal predictive mechanisms in sensorimotor processing of speech and limb movement timing. We investigated how these mechanisms are affected in Parkinson’s disease (PD) while patients performed speech and hand motor reaction time tasks in response to sensory stimuli with predictable and unpredictable temporal dynamics. Results showed slower motor reaction times in PD vs. control in response to temporally predictable, but not unpredictable stimuli. This effect was driven by faster motor responses to predictable stimuli in control subjects; however, no such effect was observed in the PD group. These findings indicated the relationship between PD pathology and sensorimotor deficits in temporal predictive mechanisms of timing processing during speech production and hand movement.     

Dysexecutive syndrome in Parkinson’s disease: the GREFEX study

The objectives of this study were to characterize the frequencies and profiles of behavioral and cognitive dysexecutive syndromes in PD (based on validated battery and diagnostic criteria) and to develop a shortened diagnostic battery. Eighty-eight non-demented patients with a diagnosis of PD were examined with an executive validated battery. Using a validated framework, the patients’ test results were interpreted with respect to normative data from 780 controls. A dysexecutive syndrome was observed in 80.6% of the patients [95% confidence interval: 71.1–90.1]. The dysexecutive profile was characterized by prominent impairments in deduction, flexibility, inhibition and initiation in the cognitive domain, and by global hypoactivity with apathy and hyperactivity in the behavioral domain. This finding implies that patients with PD should be assessed with cognitive tests and a validated inventory for behavioral dysexecutive syndromes. A shortened battery (based on three cognitive tests and three behavioral domains) provided high diagnostic accuracy.     

A Cultural Analysis of China’s Scientific Brain Drain: the Case of Chinese Immigrant Scientists in Canadian Academia

While the booming market and policy incentives of China are reversing the pattern of talent flow across the Pacific, a large proportion of the mainland Chinese immigrant scientists currently in Canadian academia have decided not to return home; meanwhile, their interactions with China in terms of brain circulation are not extensive overall. This study attempts to explore the key factors for the paradox of China’s scientific brain drain through the lens of culture, drawing on data mainly from in-depth interviews with 14 mainland Chinese immigrant scientists in Canadian academia. The theoretical framework derives from the models of cultural negotiation (Sakamoto 2001) and bidimensional acculturation (Berry, Appl Psychol 46: 5–34, 1997). Data analysis reveals that cultural factors override everything else in shaping the leave–stay decision and brain exchange behavior of these Chinese scientists, who have gone through a cultural negotiation and construction process. With a transformed perspective, these academic migrants hold firmly the new culture’s beliefs, attitudes, and behaviors; therefore, the work styles, notions, and ethics of their counterparts in China have cultural limitations and are incongruent with their practice in Canada. Meanwhile, they have been significantly influenced by Chinese cultural values, notably group orientation, hierarchy loving, self-abasement, harmony seeking, face saving, etc. The findings should shed some light on public policies aiming to realize the full value of top talents for the benefits of China, Canada, and beyond.     

Parkinson’s Disease: Patients’ Knowledge,Attitudes, and Interest in Genetic Counseling

The objective of this study was to assess the genetics knowledge of patients with Parkinson’s disease (PD), and to explore their attitudes on genetic testing and interest in genetic counseling. We surveyed 158 patients from the University of Maryland Parkinson’s Disease and Movement Disorders Center. Patients averaged a score of 63% on general genetics knowledge and 73% on PD genetics knowledge. Participants had an overall positive attitude toward genetic testing: 80% believed that the use of genetic tests among people should be promoted, and 83% would undertake genetic test for PD if it was available. Patients reported a high interest to discuss the benefits, risks, and impacts of genetic testing for PD (mean sum score?=?26, range?=?9–35), and 43% patients expressed interest in meeting with a genetic counselor. Multivariate regression analysis showed that patients who had more positive attitudes toward genetic testing for PD were more interested in meeting with a genetic counselor (β?=?0.6, p?<?0.001). This study is the first to demonstrate an interest in genetic counseling among patients with PD. Our findings demonstrate a new niche for genetic counselors to support patients in clarifying gaps or misconceptions in knowledge about PD genetics as well as the possible risks, benefits, and limitations of genetic testing.     

Functional Brain Connectivity Using fMRI in Aging and Alzheimer’s Disease

Normal aging and Alzheimer’s disease (AD) cause profound changes in the brain’s structure and function. AD in particular is accompanied by widespread cortical neuronal loss, and loss of connections between brain systems. This degeneration of neural pathways disrupts the functional coherence of brain activation. Recent innovations in brain imaging have detected characteristic disruptions in functional networks. Here we review studies examining changes in functional connectivity, measured through fMRI (functional magnetic resonance imaging), starting with healthy aging and then Alzheimer’s disease. We cover studies that employ the three primary methods to analyze functional connectivity—seed-based, ICA (independent components analysis), and graph theory. At the end we include a brief discussion of other methodologies, such as EEG (electroencephalography), MEG (magnetoencephalography), and PET (positron emission tomography). We also describe multi-modal studies that combine rsfMRI (resting state fMRI) with PET imaging, as well as studies examining the effects of medications. Overall, connectivity and network integrity appear to decrease in healthy aging, but this decrease is accelerated in AD, with specific systems hit hardest, such as the default mode network (DMN). Functional connectivity is a relatively new topic of research, but it holds great promise in revealing how brain network dynamics change across the lifespan and in disease.     

Development of the Brain’s Functional Network Architecture

A full understanding of the development of the brain’s functional network architecture requires not only an understanding of developmental changes in neural processing in individual brain regions but also an understanding of changes in inter-regional interactions. Resting state functional connectivity MRI (rs-fcMRI) is increasingly being used to study functional interactions between brain regions in both adults and children. We briefly review methods used to study functional interactions and networks with rs-fcMRI and how these methods have been used to define developmental changes in network functional connectivity. The developmental rs-fcMRI studies to date have found two general properties. First, regional interactions change from being predominately anatomically local in children to interactions spanning longer cortical distances in young adults. Second, this developmental change in functional connectivity occurs, in general, via mechanisms of segregation of local regions and integration of distant regions into disparate subnetworks.     

Mood—Creativity Relationship in Groups: The Role of Equality in Idea Contribution in Temporal Mood Effects

As people working in groups might fare better in solving complex problems than those working alone (e.g., Laughlin, Hatch, Silver, & Boh, Journal of Personality and Social Psychology, 90 , 2006 and 644), organizations have increasingly assigned creative projects to groups. Group members contribute their collective efforts over time until the creative project has come to fruition. Although mood is identified as an important antecedent to creativity, little is known about the temporal pattern of how group mood enhances or inhibits group creativity, as well as the underpinning group process that explains the mood—creativity link in groups. We set out to address these questions by taking a within-group approach to study the temporal trends of how group mood precedes group creativity and to examine idea contribution equality (ICE) as a mediating group process. We conducted a three-wave longitudinal study among student workgroups tasked to complete a creativity project over a 1-month span. Evidence showed that positive mood is positively associated with concurrent ICE and negative mood is negatively associated with lagged ICE. Furthermore, a mediation model showed that negative mood eventually hampered expert-rated group creative performance by reducing ICE over time. These findings add new knowledge to the temporal mood—creativity relation within the group context.     

A Case Study of Negative Affixes in Sadegh Hedayat’s Letters: The Effect of Bipolar Mood Disorder

This research studies the morphological features found in Sadegh Hedayat’s letters, who, based on linguistic and psychological studies, may have had bipolar disorder. It aims to assess the impact of various types of moods on the frequency of negative affixes through qualitative analysis of the letters’ text. The letters are written in Persian, and include six negative derivational affixes. As bipolar disorder includes four episodes, all letters are analyzed on the basis of six negative affixes concerning the episodes using SPSS. The results indicate that each episode shows totally different characteristics in using negative affixes. In fact, Hedayat mostly used negative affixes in depression, confirming psychological studies, and it is revealed that he mostly used negative affixes in hypomania when he experienced an irritated mood. Moreover, the frequency of negative affixes in mixed episode shows a combination of hypomania and depression, which is in agreement with previous studies. Additionally, euthymia shows few negative affixes.