Cognitive and Behavioral Neurology最新文献

Background: Brain-derived neurotrophic factor (BDNF) expression, which can be measured in blood serum, has been found to increase with aerobic exercise. The link between BDNF level, physical exercise, and genetic status (Val66Met polymorphism) has not been well researched in older adults.

Objective: To investigate the possible link between BDNF expression, acute aerobic exercise, and the Val66Met polymorphism in older adults.

Method: Twenty-three healthy older adults participated in one session of acute aerobic exercise. Their serum BDNF levels were measured both at baseline and post exercise. Saliva samples were collected to identify each individual's genetic status.

Results: At baseline, the individuals' mean serum BDNF level was 16.03 ng/mL (Val66Val = 15.89 ng/mL; Val66Met = 16.34 ng/mL); post exercise, the individuals' mean serum BDNF level was 16.81 ng/mL (Val66Val = 16.14 ng/mL; Val66Met = 18.34 ng/mL).

Conclusion: One session of acute aerobic exercise significantly increased the individuals' mean serum BDNF level. Males had higher BDNF levels than females. There was a significant interaction between gender and BDNF expression post exercise and a significant between-group effect of gender. The Val66Met carriers had a more positive response to the acute aerobic exercise compared with the Val66Val carriers, although without a significant difference between the two groups.

Dividing the brain-mind into the specialized fields of neurology and psychiatry has produced many granular advantages, but these silos have imposed barriers to comprehensively understanding and contextualizing the fundamentals governing mental life and its maladies. Scientific inquiry into these fundamentals cannot reach its full potential without interdigitating the boundaries of two specialties of the same organ for both scholarship and clinical practice. We propose that to truly integrate disorders of the brain and the mind for research and clinical care, we must carefully reexamine the classification of its disorders (nosology) as an instrument to develop a coherent pathological and psychological framework. We call on professional organizations from neurology, psychiatry, behavioral neurology, neuropsychiatry, neuropsychology, and other relevant subspecialties (eg, geriatric psychiatry) to convene a multidisciplinary task force to define the current classification principles of their subspecialties and work toward developing an integrated nosology. The effect of a shared classification system, which we acknowledge is a difficult proposition philosophically and politically, would have transformative potential across educational, clinical, scientific, programmatic, and sociocultural realms. If accomplished, this initiative would provide a definitive step toward reducing stigma (and promoting reimbursement parity) for the full spectrum of complex brain disorders (regardless of traditional neurologic vs psychiatric conceptualizations).

Since 2012, individuals with a history of opioid misuse have infrequently been observed to develop a sudden-onset amnestic syndrome associated with bilateral hippocampal-restricted diffusion on MRI. Follow-up imaging of this opioid-associated amnestic syndrome (OAS) has revealed persistent hippocampal abnormalities. Given these observations, as well as neuropathological studies demonstrating excessive tau deposition in the hippocampi and other brain regions of individuals with opioid misuse, we describe longitudinal imaging of a patient with a history of OAS from presentation through 53 months later, when tau positron emission tomography (PET) was performed. Our patient was a 21-year-old woman with a history of attention-deficit hyperactivity disorder and substance use disorder, including opioids (intravenous heroin), who was hospitalized for acute-onset, dense anterograde amnesia. Her urine toxicology screen was positive for opiates. On presentation, her brain MRI showed restricted diffusion as well as T2 and fluid-attenuated inversion recovery (FLAIR) hyperintensity of the hippocampi and globi pallidi. On day 3, magnetic resonance spectroscopy of a right hippocampal region of interest showed a mild reduction of N-acetyl aspartate/creatine, slight elevation of choline/creatine, and the appearance of lactate/lipid and glutamate/glutamine peaks. At 4.5 months, there was resolution of restricted diffusion on MRI, although a minimal anterior T2 and FLAIR hyperintense signal in the right hippocampus persisted. However, by 53 months, when mild memory loss was reported, the hippocampi appeared normal on MRI, and [ 18 F]T807 (tau) PET showed no uptake suggestive of tau deposition. This case report supports the investigation into the hypothesis that OAS may follow a trajectory of reversible metabolic injury.

Background and objective: Implicit social cognition refers to attitudes and stereotypes that may reside outside conscious awareness and control but that still affect human behavior. In particular, the implicit favoritism of an ingroup, to which an individual belongs, as opposed to an outgroup, to which the individual does not belong, characterized as ingroup bias, is of interest and is investigated here.

Method: We used a Go/NoGo association task (GNAT) and behavioral and electroencephalographic (event-related EEG potential [ERP] analysis) measures to investigate the implicit bias toward cities in East Germany, West Germany, and Europe, in 16 individuals each from West and East Germany (mixed gender, M age = 24). The GNAT assesses an individual's Go and NoGo responses for a given association between a target category and either pole (positive or negative) of an evaluative dimension.

Results: Behavioral measures revealed slightly faster reaction times to the combination of European city names and negative, as compared with positive, evaluative words in both groups. ERP analysis showed an increased negativity at 400-800 ms poststimulus in the incongruent conditions of East German city/positive word pairings (in West Germans) and West German city/positive word pairings (in East Germans).

Conclusion: An implicitly moderately negative evaluation of Europe by both groups was exhibited based on the behavioral data, and an increased level of conflict arising from the "incongruent" pairings (ie, as manifestation of an implicitly negative attitude toward East Germany in West Germans, and toward West Germany in East Germans) was exhibited based on the electrophysiological data.

Background: Apathy, characterized by a quantifiable reduction in motivation or goal-directed behavior, is a multidimensional syndrome that has been observed across many neurodegenerative diseases.

Objective: To develop a novel task measuring spontaneous action initiation (ie, a nonverbal equivalent to spontaneous speech tasks) and to investigate the association between apathy and executive functions such as the voluntary initiation of speech and actions and energization (ie, ability to initiate and sustain a response).

Method: We compared the energization and executive functioning performance of 10 individuals with neurodegenerative disease and clinically significant apathy with that of age-matched healthy controls (HC). We also investigated the association between self-reported scores on the Apathy Evaluation Scale (AES) and performance on energization tasks.

Results: The individuals with apathy made significantly fewer task-related actions than the HC on the novel spontaneous action task, and their scores on the AES were negatively correlated with spontaneous task-related actions, providing preliminary evidence for the task's construct validity. In addition, the individuals with apathy performed more poorly than the HC on all of the energization tasks, regardless of task type or stimulus modality, suggesting difficulty in sustaining voluntary responding over time. Most of the tasks also correlated negatively with the AES score. However, the individuals with apathy also performed more poorly on some of the executive function tasks, particularly those involving self-monitoring.

Conclusion: Our work presents a novel experimental task for measuring spontaneous action initiation-a key symptom of apathy-and suggests a possible contribution of apathy to neuropsychological deficits such as poor energization.

Background: Typical adults most frequently orient their attention to other people's eyes, whereas individuals with autism spectrum disorder (ASD) orient their attention to other people's mouths. Typical adults also reveal visuospatial biases on tasks such as vertical and horizontal line bisections. Therefore, the difference in face viewing might be related to a more general group difference in the allocation of vertical attention.

Objective: To use vertical line bisection and quadrisection tasks to evaluate whether individuals with ASD have a more downward-oriented vertical attentional bias than do typical individuals.

Method: We recruited 20 individuals with ASD and 20 control participants matched for age (6-23 years), IQ, and sex. We asked the individuals to bisect and quadrisect lines on the top and bottom when the vertical lines were placed at the intersection of their right, left, and center egocentric sagittal planes and their coronal plane. The distances from the true midpoint and quadripoint were measured, and between-group performances were compared.

Results: No significant difference was found between the ASD and control groups for vertical line bisections or lower line quadrisections. However, when the ASD group was compared with the control group for higher line quadrisections, the ASD group exhibited a greater upward deviation.

Conclusion: There is no downward vertical attentional spatial bias associated with ASD that could help to explain these individuals' attentional bias toward the mouth. However, additional studies are required to learn if this atypical upward vertical attentional bias might account for some of the symptoms and signs associated with ASD.