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Background: Cerebrovascular disease is a common cause of dementia in older adults, and potentially preventable with early intervention. Oxylipins are produced from the oxidation of long-chain polyunsaturated fatty acids (PUFA) possessing potent vascular effects. Oxylipins generated from the cytochrome P450 pathway are enzymatically converted to diols by soluble epoxide hydrolase (sEH); sEH products have been associated with small vessel ischemic disease. Little is known about oxylipins' impact on markers of dementia risk.Objective: An exploratory examination of the association between omega-6 and omega-3 derived oxylipins, brain MRI, and cognition.Methods: Thirty-seven non-demented participants with controlled hypertension (mean age 65.6 years) were enrolled in a dementia prevention study investigating fish oil and lipoic acid on preserving cognitive function. Baseline associations between plasma oxylipins, white matter hyperintensity (WMH), and Trails-B were examined using linear regression. P450-derived diol/epoxide ratio was an indirect measure of sEH activity.Results: Omega-6 derived 9-HODE was associated with increased WMH (p = 0.017) and reduced grey matter volume (p = 0.02). Omega-6 P450-derived diol/epoxide ratio 9,10-DiHOME/9,10-EpOME was associated with increased WMH (p = 0.035) and poorer performance on Trails-B (p = 0.05); ratio14,15-DHET/14,15-EET was associated with increased WMH (p = 0.045). Omega-3 P450-derived diol/epoxide ratio 19,20-DiHDPE/19,20-EpDPE was associated with increased WMH (p = 0.04) and poorer performance on Trails-B (p = 0.04). Arachidonic acid was associated with better performance on Trails-B (p = 0.012); Omega-3 derived 16,17-EpDPE was associated with decreased WMH (p = 0.005).Conclusions: With the exception of arachidonic acid, it was specific oxylipin products, not their parent PUFAs, that were associated with unfavorable and favorable MRI and cognitive markers of dementia risk. [ABSTRACT FROM AUTHOR]

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Background: Autism Spectrum Disorder (ASD) is a neurodevelopmental disorder. According to the DSM-V, this condition has a variety of symptoms including impaired social relationships, and behavioral disorders. Various studies have shown that these children also have balance problems that are rarely investigated in this population. The purpose was to investigate the effect of single- and dual-task exercises on the functional balance of these children. Methods: The study design was a clinical trial research. The participants were 40 children with ASD (9 to 14 years) who were randomly divided into two groups. The single-task exercise group only performed balance exercises, while the dual-task exercises group performed both balance exercises and cognitive tasks at the same time. The sessions consisted of 45-min sessions (3 times a week for 4 weeks). The functional balance tests were performed before and after the intervention. Results: There were no significant differences between two groups in the Timed Up and Go test, 10-meter walk test and Mini-BESTest endpoint of the study, but there was a significant difference in Pediatric Berg Balance Scale (p=0.01, effect size=0.82). Dual-task exercises could not cause significant improvements in the functional balance of the participants compared to the single-task group. Conclusion: It seems that evidence that dual-task exercises cause significant improvements of functional balance of the participants compared to the single-task group is inconclusive. [ABSTRACT FROM AUTHOR]

Objective: Our study examined the impact of sex, ADHD subtype, and comorbid illnesses (depression/anxiety) on the timing of diagnosis and treatment for ADHD. Method: To analyze ADHD patients, four health databases were used to assess subtype, comorbid mood, and antidepressant or anxiolytic drug exposure. Analyses were stratified by sex and age. Standardized mean differences measured intergroup differences. Results: Females with ADHD were identified at older ages and had higher rates of depression and anxiety diagnoses and treatments before and after their initial ADHD diagnosis. Predominantly inattentive ADHD patients were diagnosed later and more likely to receive mood disorder diagnosis and treatment than hyperactive impulsive ADHD patients. Conclusions: Results suggest a more complex ADHD presentation in females, potentially causing late diagnosis and delayed treatment. [ABSTRACT FROM AUTHOR]

Sleep and brain/cognitive/neural reserve significantly impact well-being and cognition throughout life. This review aims to explore the intricate relationship between such factors, with reference to their effects on human cognitive functions. The specific goal is to understand the bidirectional influence that sleep and reserve exert on each other. Up to 6 February 2024, a methodical search of the literature was conducted using the PubMed database with terms related to brain, cognitive or neural reserve, and healthy or disturbed sleep. Based on the inclusion criteria, 11 articles were selected and analyzed for this review. The articles focus almost exclusively on cognitive reserve, with no explicit connection between sleep and brain or neural reserve. The results evidence sleep's role as a builder of cognitive reserve and cognitive reserve's role as a moderator in the effects of physiological and pathological sleep on cognitive functions. In conclusion, the findings of the present review support the notion that both sleep and cognitive reserve are critical factors in cognitive functioning. Deepening comprehension of the interactions between them is essential for devising strategies to enhance brain health and resilience against age- and pathology-related conditions. [ABSTRACT FROM AUTHOR]

Evidence in the literature indicates that aerobic physical activity may have a protective role in aging pathologies. However, it has not been clarified whether different types of aerobic exercise produce different effects. In particular, these potential differences have not been explored in patients with Alzheimer's disease (AD). The present narrative review has the specific aim of evaluating whether land (walking/running) and water (swimming) aerobic activities exert different effects on cognitive functions and neural correlates in AD patients. In particular, the investigation is carried out by comparing the evidence provided from studies on AD animal models and on patients. On the whole, we ascertained that both human and animal studies documented beneficial effects of land and water aerobic exercise on cognition in AD. Also, the modulation of numerous biological processes is documented in association with structural modifications. Remarkably, we found that aerobic activity appears to improve cognition per se, independently from the specific kind of exercise performed. Aerobic exercise promotes brain functioning through the secretion of molecular factors from skeletal muscles and liver. These molecular factors stimulate neuroplasticity, reduce neuroinflammation, and inhibit neurodegenerative processes leading to amyloid-β accumulation. Additionally, aerobic exercise improves mitochondrial activity, reducing oxidative stress and enhancing ATP production. Aerobic activities protect against AD, but implementing exercise protocols for patients is challenging. We suggest that health policies and specialized institutions should direct increasing attention on aerobic activity as lifestyle modifiable factor for successful aging and age-related conditions. [ABSTRACT FROM AUTHOR]

Subtle cognitive and behavioral changes are common in early Parkinson's disease. The cause of these symptoms is probably multifactorial but may in part be related to extra-striatal dopamine levels. 6-[(18) F]-Fluoro-L-dopa (FDOPA) positron emission tomography has been widely used to quantify dopamine metabolism in the brain; the most frequently measured kinetic parameter is the tissue uptake rate constant, Ki. However, estimates of dopamine turnover, which also account for the small rate of FDOPA loss from areas of specific trapping, may be more sensitive than Ki for early disease-related changes in dopamine biosynthesis. The purpose of the present study was to compare effective distribution volume ratio (eDVR), a metric for dopamine turnover, to cognitive and behavioral measures in Parkinson's patients. We chose to focus the investigation on anterior cingulate cortex, which shows highest FDOPA uptake within frontal regions and has known roles in executive function. Fifteen non-demented early-stage PD patients were pretreated with carbidopa and tolcapone, a central catechol-O-methyl transferase (COMT) inhibitor, and then underwent extended imaging with FDOPA PET. Anterior cingulate eDVR was compared with composite scores for language, memory, and executive function measured by neuropsychological testing, and behavior change measured using two informant-based questionnaires, the Cambridge Behavioral Inventory and the Behavior Rating Inventory of Executive Function-Adult Version. Lower mean eDVR (thus higher dopamine turnover) in anterior cingulate cortex was related to lower (more impaired) behavior scores. We conclude that subtle changes in anterior cingulate dopamine metabolism may contribute to dysexecutive behaviors in Parkinson's disease. [ABSTRACT FROM AUTHOR]

Objectives: Dysbiosis of the gut microbiome is implicated in numerous human health conditions. Animal studies have linked microbiome disruption to changes in cognitive functioning, although no study has examined this possibility in neurologically healthy older adults. Methods: Participants were 43 community-dwelling older adults (50–85 years) that completed a brief cognitive test battery and provided stool samples for gut microbiome sequencing. Participants performing≥1 SD below normative performance on two or more tests were compared to persons with one or fewer impaired scores. Results: Mann Whitney U tests revealed different distributions of Bacteroidetes (p=.01), Firmicutes (p=.02), Proteobacteria (p=.04), and Verrucomicrobia (p=.003) between Intact and Impaired groups. These phyla were significantly correlated with cognitive test performances, particularly Verrucomicrobia and attention/executive function measures. Conclusions: The current findings suggest that composition of the gut microbiome is associated with cognitive test performance in neurologically healthy older adults. Future studies are needed to confirm these findings and explore possible mechanisms. (JINS, 2017, 23, 700–705) [ABSTRACT FROM PUBLISHER]

Citicoline is the generic name of CDP-choline, a natural metabolite presents in all living cells. Used in medicine as a drug since the 1980-s, citicoline was recently pronounced a food ingredient. When ingested, citicoline breaks down to cytidine and choline, which become incorporated into their respective normal metabolic pathways. Choline is a precursor of acetylcholine and phospholipids; these is a neurotransmitter pivotal for learning and memory and important constituents of neuronal membranes and myelin sheaths, respectively. Cytidine in humans is readily converted to uridine, which exerts a positive effect on synaptic function and supports the formation of synaptic membranes. Choline deficiency has been found to be correlated with memory dysfunction. Magnetic resonance spectroscopy studies showed that citicoline intake improves brain uptake of choline in older persons, suggestive of that it shall help in reversing early age-related cognitive changes. In randomized, placebo-controlled trials of cognitively normal middle-aged and elderly persons, positive effects of citicoline on memory efficacy were found. Similar effects of citicoline on memory indices were also found in patients suffering from mild cognitive impairment and some other neurological diseases. Altogether, the aforementioned data provide complex and unambiguous evidence supporting the claim that oral citicoline intake positively influences memory function in humans who encounter age-related memory impairment also in the absence of any detectable neurological or psychiatric disease. [ABSTRACT FROM AUTHOR]

Background: Theory of Mind (ToM) is an ability to infer the mental state of others, which plays an important role during social events. Previous studies have shown that ToM deficits exist frequently in schizophrenia, which may result from abnormal activity in brain regions related to sociality. However, the interactions between brain regions during ToM processing in schizophrenia are still unclear. Therefore, in this study, we investigated functional connectivity during ToM processing in patients with schizophrenia, using functional magnetic resonance imaging (fMRI). Methods: A total of 36 patients with schizophrenia and 33 healthy controls were recruited to complete a ToM task from the Human Connectome Project (HCP) during fMRI scanning. Psychophysiological interaction (PPI) analysis was applied to explore functional connectivity. Results: Patients with schizophrenia were less accurate than healthy controls in judging social stimuli from non-social stimuli (Z = 2.31, p = 0.021), and displayed increased activity in the right inferior frontal gyrus and increased functional connectivity between the bilateral middle temporal gyrus and the ipsilateral parahippocampal gyrus during ToM processing (AlphaSim corrected p < 0.05). Conclusions: Here, we showed that the brain regions related to sociality interact more with the parahippocampal gyrus in patients with schizophrenia during ToM processing, which may reflect a possible compensatory pathway of ToM deficits in schizophrenia. Our study provides a new idea for ToM deficits in schizophrenia, which could be helpful to better understand social cognition of schizophrenia. [ABSTRACT FROM AUTHOR]

In Parkinson's disease (PD), reduced cerebral cortical thickness may reflect network-based degeneration. This study performed cognitive assessment and brain MRI in 30 PD participants and 41 controls at baseline and 18 months later. We hypothesized that cerebral cortical thickness and volume, as well as change in these metrics, would differ between PD participants who remained cognitively stable and those who experienced cognitive decline. Dividing the participant sample into PD-stable, PD-decline, and control-stable groups, we compared mean cortical thickness and volume within segments that comprise the prefrontal cognitive-control, memory, dorsal spatial, and ventral object-based networks at baseline. We then compared the rate of change in cortical thickness and volume between the same groups using a vertex-wise approach. We found that the PD-decline group had lower cortical thickness within all 4 cognitive networks in comparison with controls, as well as lower cortical thickness within the prefrontal and medial temporal networks in comparison with the PD-stable group. The PD-decline group also experienced a greater rate of volume loss in the lateral temporal cortices in comparison with the control group. This study suggests that lower thickness and volume in prefrontal, medial, and lateral temporal regions may portend cognitive decline in PD. [ABSTRACT FROM AUTHOR]

Symptoms are known to account for a small variance in some cognitive functions in schizophrenia, but the influence of self-perceived mood remains largely unknown. The authors examined the influence of subjective mood states, psychopathology, and depressive symptoms in cognitive performance in a single investigation in schizophrenia. A group of 40 stable medicated patients with schizophrenia (20 men, 20 women) and 30 healthy comparison subjects (15 men, 15 women) were assessed on neurocognitive measures of verbal abilities, attention, executive functioning, language, memory, motor functioning, and information processing. All subjects provided self-ratings of mood prior to cognitive testing. Patients were also rated on psychopathology and depressive symptoms. Patients performed worse than comparison subjects on most cognitive domains. Within the patient group, subjective feelings of depression-dejection, fatigue-inertia, confusion, and tension-anxiety predicted (controlling for symptoms) poor performance on measures of attention, executive function, and verbal memory. In the same group of patients, clinician-rated symptoms of psychopathology and depression predicted significantly poor performance only on tests of motor function. In comparison subjects, vigor related to better, and fatigue and inertia to worse, spatial motor performance. Self-perceived negative mood state may be a better predictor of cognitive deficits than clinician-rated symptoms in chronic schizophrenia patients. [ABSTRACT FROM PUBLISHER]

Background: Neurofilament light chain (NfL) is released into the blood during neuronal damage. NfL is linked to mortality in neurological disorders, remaining unexplored in population studies. We investigated whether initial (v1) and annualized change (δ) in plasma NfL can predict all-cause mortality in middle-aged dementia-free urban adults.Methods: Longitudinal data were from 694 participants in the Healthy Aging in Neighborhoods of Diversity Across the Life Span study (HANDLS, mean agev1: 47.8 years, 42% male, 55.8% African American). Plasma NfL was measured prospectively at three visits. Analyses included Cox proportional hazards models for all-cause mortality risk and 4-way decomposition testing for interaction and mediation.Results: Unlike men, women exhibited a direct association between δNfL (above vs. below median) and all-cause mortality risk in both the minimally (HR = 3.91, 95% CI 1.10-13.9, p = 0.036) and fully adjusted models (HR = 4.92, 95% CI 1.26-19.2, p = 0.022), and for δNfL (per unit increase) in the full model (HR = 1.65, 95% CI 1.04-2.61, p = 0.034). In both models, and among women, 1 standard deviation of NfLv1 was associated with an increased all-cause mortality risk (reduced model: HR = 2.01, 95% CI 1.24-3.25, p = 0.005; full model: HR = 1.75, 95% CI 1.02-2.98, p = 0.041). Only few interactions were detected for cardio-metabolic risk factors. Notably, NfLv1 was shown to be a better prognostic indicator at normal hsCRP values among women, while HbA1c and δNfL interacted synergistically to determine mortality risk, overall.Conclusions: These findings indicate that plasma NfL levels at baseline and over time can predict all-cause mortality in women and interacts with hsCRP and HbA1c to predict that risk. [ABSTRACT FROM AUTHOR]

Resting-state functional magnetic resonance imaging (rs-fMRI), which measures the spontaneous fluctuations in the blood oxygen level-dependent (BOLD) signal, is increasingly utilized for the investigation of the brain's physiological and pathological functional activity. Rodents, as a typical animal model in neuroscience, play an important role in the studies that examine the neuronal processes that underpin the spontaneous fluctuations in the BOLD signal and the functional connectivity that results. Translating this knowledge from rodents to humans requires a basic knowledge of the similarities and differences across species in terms of both the BOLD signal fluctuations and the resulting functional connectivity. This review begins by examining similarities and differences in anatomical features, acquisition parameters, and preprocessing techniques, as factors that contribute to functional connectivity. Homologous functional networks are compared across species, and aspects of the BOLD fluctuations such as the topography of the global signal and the relationship between structural and functional connectivity are examined. Time-varying features of functional connectivity, obtained by sliding windowed approaches, quasi-periodic patterns, and coactivation patterns, are compared across species. Applications demonstrating the use of rs-fMRI as a translational tool for cross-species analysis are discussed, with an emphasis on neurological and psychiatric disorders. Finally, open questions are presented to encapsulate the future direction of the field. [ABSTRACT FROM AUTHOR]

The diameter of the human pupil tracks working memory processing and is associated with activity in the frontoparietal network. At the same time, recent neuroimaging research has linked human pupil fluctuations to activity in the salience network. In this combined functional magnetic resonance imaging (fMRI)/pupillometry study, we recorded the pupil size of healthy human participants while they performed a blockwise organized working memory task (N‐back) inside an MRI scanner in order to monitor the pupil fluctuations associated neural activity during working memory processing. We first confirmed that mean pupil size closely followed working memory load. Combining this with fMRI data, we focused on blood oxygen level dependent (BOLD) correlates of mean pupil size modeled onto the task blocks as a parametric modulation. Interrogating this modulated task regressor, we were able to retrieve the frontoparietal network. Next, to fully exploit the within‐block dynamics, we divided the blocks into 1 s time bins and filled these with corresponding pupil change values (first‐order derivative of pupil size). We found that pupil change within N‐back blocks was positively correlated with BOLD amplitudes in the areas of the salience network (namely bilateral insula, and anterior cingulate cortex). Taken together, fMRI with simultaneous measurement of pupil parameters constitutes a valuable tool to dissect working memory subprocesses related to both working memory load and salience of the presented stimuli. [ABSTRACT FROM AUTHOR]

Introduction: This study examined the relationship between cardiorespiratory fitness (CRF) and longitudinal cognitive functioning in a cohort enriched with risk factors for Alzheimer's disease (AD). Methods: A total of 155 enrollees in the Wisconsin Registry for Alzheimer's Prevention completed repeat comprehensive neuropsychological evaluations that assessed six cognitive domains. Peak oxygen consumption (VO2peak) was the primary measure of CRF. Random effects regression was used to investigate the effect of CRF on cognitive trajectories. Results: Higher CRF was associated with slower decline in the cognitive domains of verbal learning and memory (P <.01) and visual learning and memory (P <.042). Secondary analyses indicated that these effects were stronger among men than women, and for noncarriers of the apolipoprotein E ε4 allele. Discussion: Higher CRF was associated with a slower rate of the decline in episodic memory that occurs as a natural consequence of aging in a cohort enriched with risk factors for AD. [ABSTRACT FROM AUTHOR]

Obesity imposes serious health risks and involves alterations in resting‐state functional connectivity of brain networks involved in eating behavior. Bariatric surgery is an effective treatment, but its effects on functional connectivity are still under debate. In this pre‐registered study, we aimed to determine the effects of bariatric surgery on major resting‐state brain networks (reward and default mode network) in a longitudinal controlled design. Thirty‐three bariatric surgery patients and 15 obese waiting‐list control patients underwent magnetic resonance imaging at baseline, after 6 and 12 months. We conducted a pre‐registered whole‐brain time‐by‐group interaction analysis, and a time‐by‐group interaction analysis on within‐network connectivity. In exploratory analyses, we investigated the effects of weight loss and head motion. Bariatric surgery compared to waiting did not significantly affect functional connectivity of the reward network and the default mode network (FWE‐corrected p >.05), neither whole‐brain nor within‐network. In exploratory analyses, surgery‐related BMI decrease (FWE‐corrected p =.041) and higher average head motion (FWE‐corrected p =.021) resulted in significantly stronger connectivity of the reward network with medial posterior frontal regions. This pre‐registered well‐controlled study did not support a strong effect of bariatric surgery, compared to waiting, on major resting‐state brain networks after 6 months. Exploratory analyses indicated that head motion might have confounded the effects. Data pooling and more rigorous control of within‐scanner head motion during data acquisition are needed to substantiate effects of bariatric surgery on brain organization. [ABSTRACT FROM AUTHOR]

The increased prevalence and adverse health consequences of obesity have made it one of the leading public health issues in recent years. Importantly, several epidemiological studies have revealed significant associations between BMI and organic food consumption. However, although these studies have suggested that this factor holds promise to prevent obesity, they all suffer from methodological limitations, including self-reporting methods to assess BMI, not controlling for potential confounding factors or using a non-representative sample. Moreover, all were restricted to an adult sample. We present the results of a cross-sectional epidemiological study assessing the association of organic food consumption with BMI and obesity in a representative lifespan French sample (INCA3 study). Objective methods were used to measure BMI, and several potentially confounding variables were controlled for. In total, 1775 children and adolescents and 2121 adults underwent anthropometric measurements and completed questionnaires concerning their dietary habits and lifestyle. Unadjusted models systematically revealed negative associations between organic food consumption and both BMI and obesity across all age groups. These associations tended to remain statistically significant even after controlling for several confounding variables concerning socio-economic status, quality of the diet and physical activity. The effect sizes were, however, small. These data confirm the association between organic food consumption and obesity during both childhood and adulthood. Evidence from randomised controlled trials is required to investigate causality between organic food consumption and lower BMI or obesity rate. [ABSTRACT FROM AUTHOR]

BACKGROUND: Acquired brain injuries often cause cognitive impairment, significantly impacting participation in rehabilitation and activities of daily living. Music can influence brain function, and thus may serve as a uniquely powerful cognitive rehabilitation intervention. OBJECTIVE: This feasibility study investigated the potential effectiveness of music-based cognitive rehabilitation for adults with chronic acquired brain injury. METHODS: The control group participated in three Attention Process Training (APT) sessions, while the experimental group participated in three Music Attention Control Training (MACT) sessions. Pre-and post- testing used the Trail Making A & B, Digit Symbol, and Brown-Peterson Task as neuropsychological tests. RESULTS: ANOVA analyses showed no significant difference between groups for Trail A Test, Digit Symbol, and Brown-Peterson Task. Trail B showed significant differences at post-test favouring MACT over APT. The mean difference time between pre-and post-tests for the Trail B Test was also significantly different between APT and MACT in favour of MACT using a two-sample t-test as well as a follow-up nonparametric Mann Whitney U-test. CONCLUSIONS: The group differences found in the Trail B tests provided preliminary evidence for the efficacy of MACT to arouse and engage attention in adults with acquired brain injury. [ABSTRACT FROM AUTHOR]

Motor Neuron Disease (MND) is a fatal neurodegenerative condition, which is characterized by the selective loss of the upper and lower motor neurons. At the sites of motor neuron injury, accumulation of activated microglia, the primary immune cells of the central nervous system, is commonly observed in both human post mortem studies and animal models of MND. Microglial activation has been found to correlate with many clinical features and importantly, the speed of disease progression in humans. Both anti‐inflammatory and pro‐inflammatory microglial responses have been shown to influence disease progression in humans and models of MND. As such, microglia could both contribute to and protect against inflammatory mechanisms of pathogenesis in MND. While murine models have characterized the microglial response to MND, these studies have painted a complex and often contradictory picture, indicating a need for further characterization in humans. This review examines the potential role microglia play in MND in human and animal studies. Both the pro‐inflammatory and anti‐inflammatory responses will be addressed, throughout the course of disease, followed by the potential of microglia as a target in the development of disease‐modifying treatments for MND. [ABSTRACT FROM AUTHOR]

By 2050, the global population of people aged 65 years or older will triple. While this is accompanied with an increasing burden of age‐associated diseases, it also emphasizes the need to understand the effects of healthy aging on cognitive processes. One such effect is a general slowing of processing speed, which is well documented in many domains. The execution of anti‐saccades depends on a well‐established brain‐wide network ranging from various cortical areas and basal ganglia through the superior colliculus down to the brainstem saccade generators. To clarify the consequences of healthy aging as well as gender on the execution of reflexive and voluntary saccades, we measured a large sample of healthy, non‐demented individuals (n = 731, aged 51–84 years) in the anti‐saccade task. Age affected various aspects of saccade performance: The number of valid trials decreased with age. Error rate, saccadic reaction times (SRTs), and variability in saccade accuracy increased with age, whereas anti‐saccade costs, accuracy, and peak velocity of anti‐saccades and direction errors were not affected by age. Gender affected SRTs independent of age and saccade type with male participants having overall shorter SRTs. Our rigid and solid statistical testing using linear mixed‐effect models provide evidence for a uniform slowing of processing speed independent of the actually performed eye movement. Our data do not support the assumption of a specific deterioration of frontal lobe functions with aging. [ABSTRACT FROM AUTHOR]

Background: Cannabis smoking and cigarette smoking often co-occur, yet limited research has investigated the potentially different role impulsivity may play when these behaviours occur in isolation, compared with in combination.Aims: This study examined trait and behavioural impulsivity as a function of both cigarette and cannabis smoking.Methods: Trait impulsivity (BIS-11) was compared between 44 non-smokers, 76 cigarette only, 47 cannabis only and 58 cannabis plus cigarette smokers. The effects of cigarette and cannabis smoking on behavioural impulsivity (stop-signal and information sampling tasks) were then assessed in 87 of these participants during a laboratory session.Results: Trait impulsivity was significantly higher in cigarette smokers than non-smokers, irrespective of cannabis use, except for motor impulsivity, where cigarette smoking was only associated with elevated trait impulsivity in non-smokers of cannabis. Dimensions of trait impulsivity were significantly positively related to cigarette smoking frequency and nicotine dependence, but not to cannabis smoking frequency or dependence. Smoking cigarettes or cannabis was associated with significantly impaired reflection impulsivity relative to not smoking either substance. However, no additional increases in reflection impulsivity were observed in those who smoked both cigarettes and cannabis. No group differences in response inhibition were detected.Conclusions: Heightened trait impulsivity appears to be uniquely related to cigarette smoking, whilst the smoking of cigarettes or cannabis is associated with impairments in reflection impulsivity. Improved outcomes for treating cannabis dependence may result from encouraging concomitant cigarette smokers to cease using both drugs simultaneously in order to reduce heightened impulsivity and risk of relapse. [ABSTRACT FROM AUTHOR]

Objectives: Number of mood episodes (NoE) may be an important prognostic indicator in bipolar disorder, with implications for treatment. However, NoE has been conceptualized and measured inconsistently throughout the literature. This review examines the construct of NoE in bipolar disorder, with the aim of enhancing its conceptualization and measurement. Methods: A critical evaluation of literatures on important correlates of NoE, conceptually and phenomenologically overlapping features, and previous studies considering and measuring this construct was undertaken. Results: The literature indicates that despite frequent use, NoE has been inconsistently defined and measured. Multiple studies have linked NoE with important clinical factors, including relapse, functioning, cognitive impairment and the effectiveness of both pharmacological and psychosocial interventions, yet conclusions are limited by its inconsistent treatment. Additionally, it seems evident that that NoE may best be treated as a fuzzy construct (rather than precise figure), with yet to be defined overlaps with clinical variables such as age at onset and severity. Attempts to measure this construct have varied in comprehensiveness and structure. Conclusions: The NoE construct may have important implications for individuals with bipolar disorders. However, more consistent and systematic definition and assessment of NoE is required to advance this literature and clarify its role. Recommendations aimed at advancing the conceptualization and the measurement of NoE are provided. Conceptualization may be advanced by considering and exploring relationships between NoE and factors with which it overlaps, while measurement may best be improved with increased consistency and balancing accuracy with feasibility. [ABSTRACT FROM AUTHOR]

The goal of this study was to examine whether hippocampal volume or resting-state functional connectivity (rsFC) patterns are associated with subjective memory decline (SMD) in cognitively normal aged adults. Magnetic resonance imaging data from 53 participants (mean age: 71.9 years) of the Boston University Alzheimer's Disease Center registry were used in this cross-sectional study. Separate analyses treating SMD as a binary and continuous variable were performed. Subfield volumes were generated using FreeSurfer v6.0, and rsFC strength between the head and body of the hippocampus and the rest of the brain was calculated. Decreased left whole hippocampal volume and weaker rsFC strength between the right body of the hippocampus and the default mode network (DMN) were found in SMD+. Cognitive Change Index score was not correlated with volumetric measures but was inversely correlated with rsFC strength between the right body of the hippocampus and 6 brain networks, including the DMN, task control, and attentional networks. These findings suggest that hippocampal rsFC patterns reflect the current state of SMD in cognitively normal adults and may reflect subtle memory changes that standard neuropsychological tests are unable to capture. [ABSTRACT FROM AUTHOR]

Objectives: Vortioxetine has already shown its efficacy in the acute and long-term treatment of major depressive disorder (MDD) and its potential interest in the prevention of relapse. The aim of this study was to review the current status of knowledge regarding its cognitive effects. Methods: We conducted a review of key data obtained from preclinical behavioral models and clinical trials in MDD focusing on vortioxetine-induced cognitive changes. Results: In animals, acute and chronic administration of vortioxetine improves performance on objective measures that cover a broad range of cognitive domains. In human, vortioxetine appears to be a useful treatment option in MDD patients with cognitive dysfunction. Conclusion: Vortioxetine constitutes a promising treatment for treatment of cognitive impairment in MDD, but its place in the therapeutic armamentarium still needs to be determined. [ABSTRACT FROM AUTHOR]

BACKGROUND: Contemporary goals of rehabilitation after traumatic brain injury (TBI) aim to improve cognitive and motor function by applying concepts of neuroplasticity. This can be challenging to carry out in TBI patients with motor, balance, and cognitive impairments. OBJECTIVE: To determine whether use of dynamic body-weight support (DBWS) would allow safe administration of intensive motor therapy during inpatient rehabilitation and whether its use would yield greater improvement in functional recovery than standard-of-care (SOC) therapy in adults with TBI. METHODS: Data in this retrospective cohort study was collected from patients with TBI who receive inpatient rehabilitation incorporating DBWS (n = 6) and who received inpatient rehabilitation without DBWS (SOC, n = 6). The primary outcome measure was the change in Functional Independence Measures (FIM) scores from admission to discharge. RESULTS: There was significant improvement in total FIM scores at discharge compared to admission for both the DBWS (p = 0.001) and SOC (p = 0.005) groups. Overall, the DBWS group had greater improvement in total FIM score and FIM subscales compared to the SOC group. CONCLUSIONS: Our results suggest DBWS has the potential to allow a greater intensity of therapy during inpatient rehabilitation and yield better outcomes compared to SOC in patients with TBI. [ABSTRACT FROM AUTHOR]

Objectives: Written text contains verbal immediacy cues-word form or grammatical cues that indicate positive attitude or liking towards an object, action, or person. We asked if adults with moderate-severe traumatic brain injury (TBI) would respond to these cues, given evidence of TBI-related social communication impairments.Methods: Sixty-nine adults with TBI and 74 healthy comparison (HC) peers read pairs of sentences containing different types of immediacy cues (e.g., speaker A said "these Canadians" vs. B said "those Canadians.") and identified which speaker (A or B) had a more positive attitude towards the underlined entity (Task 1); and pairs of sentences comprised of a context sentence (e.g., Fred is asked, "Did you visit Joan and Sue?") and a statement sentence (Fred says, "I visited Sue and Joan.") and were asked to indicate how much Fred liked or disliked the underlined words (Task 2).Results: HC group scores were significantly higher on Task 1, indicating more sensitivity to cues. On Task 2, TBI and HC group ratings differed across cue types and immediacy types, and the TBI group appeared to have less sensitivity to these cues.Conclusions: Findings suggest that TBI-related impairments may reduce sensitivity to subtle social cues in text. [ABSTRACT FROM AUTHOR]

Objectives: This report examined theta-band neurodynamics for potential biomarkers of brain health in athletes with concussion. Methods: Participants included college-age contact/collision athletes with (N =24) and without a history of concussion (N =16) in Study 1. Study 2 (N =10) examined changes over time in contact/collision athletes. There were two primary dependent variables: (1) theta-band phase-synchronization (e.g., functional connectivity) between medial and right-lateral electrodes; and (2) the within-subject correlation between synchronization strength on error trials and post-error reaction time (i.e., operationalization of cognitive control). Results: Head injury history was inversely related with medial-lateral connectivity. Head injury was also related to declines in a neurobehavioral measure of cognitive control (i.e., the single-trial relationship between connectivity and post-error slowing). Conclusions: Results align with a theory of connectivity-mediated cognitive control. Mild injuries undetectable by behavioral measures may still be apparent on direct measures of neural functioning. This report demonstrates that connectivity and cognitive control measures may be useful for tracking recovery from concussion. Theoretically relevant neuroscientific findings in healthy adults may have applications in patient populations, especially with regard to monitoring brain health. (JINS 2019, 25 , 314–323) [ABSTRACT FROM AUTHOR]

Abstract: Postmortem studies of Parkinson's disease (PD) suggest that Lewy body pathology accumulates in a predictable topographical sequence, beginning in the olfactory bulb, followed by caudal brainstem, substantia nigra, limbic cortex, and neocortex. Diffusion‐weighted imaging (DWI) is sensitive, if not specific, to early disease‐related white matter (WM) change in a variety of traumatic and degenerative brain diseases. Although numerous cross‐sectional studies have reported DWI differences in cerebral WM in PD, only a few longitudinal studies have investigated whether DWI change exceeds that of normal aging or coincides with regional Lewy body accumulation. This study mapped regional differences in the rate of DWI‐based microstructural change between 29 PD patients and 43 age‐matched controls over 18 months. Iterative within‐ and between‐subject tensor‐based registration was completed on motion‐ and eddy current‐corrected DWI images, then baseline versus follow‐up difference maps of fractional anisotropy, mean, radial, and axial diffusivity were analyzed in the Biological Parametric Mapping toolbox for MATLAB. This analysis showed that PD patients had a greater decline in WM integrity in the rostral brainstem, caudal subcortical WM, and cerebellar peduncles, compared with controls. In addition, patients with unilateral clinical signs at baseline experienced a greater rate of WM change over the 18‐month study than patients with bilateral signs. These findings suggest that rate of WM microstructural change in PD exceeds that of normal aging and is maximal during early stage disease. In addition, the neuroanatomic locations (rostral brainstem and subcortical WM) of accelerated WM change fit with current theories of topographic disease progression. [ABSTRACT FROM AUTHOR]

Background: Methamphetamine (MA) abuse causes immune dysfunction and neuropsychiatric impairment. The mechanisms underlying these deficits remain unidentified. Methods: The effects of MA on anxiety-like behavior and immune function were investigated in mice selectively bred to voluntarily consume high amounts of MA [i.e., MA high drinking (MAHDR) mice]. MA (or saline) was administered to mice using a chronic (14-day), binge-like model. Performance in the elevated zero maze (EZM) was determined 5 days after the last MA dose to examine anxiety-like behavior. Cytokine and chemokine expressions were measured in the hippocampus using quantitative polymerase chain reaction (qPCR). Human studies were also conducted to evaluate symptoms of anxiety using the General Anxiety Disorder-7 Scale in adults with and without a history of MA dependence. Plasma samples collected from human research participants were used for confirmatory analysis of murine qPCR results using an enzyme-linked immunosorbent assay. Results: During early remission from MA, MAHDR mice exhibited increased anxiety-like behavior on the EZM and reduced expression of chemokine (C-C motif) ligand 3 (ccl3) in the hippocampus relative to saline-treated mice. Human adults actively dependent on MA and those in early remission had elevated symptoms of anxiety as well as reductions in plasma levels of CCL3, relative to adults with no history of MA abuse. Conclusions: The results highlight the complex effects of MA on immune and behavioral function and suggest that alterations in CCL3 signaling may contribute to the mood impairments observed during remission from MA addiction. [ABSTRACT FROM AUTHOR]

According to contemporary views, the lateral frontal cortex is organized along a rostro-caudal functional axis with increasingly complex cognitive/behavioral control implemented rostrally, and increasingly detailed motor control implemented caudally. Whether themedial frontal cortex follows the same organization remains to be elucidated. To address this issue, the functional connectivity of the 3 cingulate motor areas (CMAs) in the human brain with the lateral frontal cortex was investigated. First, the CMAs and their representations of hand, tongue, and eye movements were mapped via task-related functional magnetic resonance imaging (fMRI). Second, using resting-state fMRI, their functional connectivity with lateral prefrontal and lateral motor cortical regions of interest (ROIs) were examined. Importantly, the above analyses were conducted at the single-subject level to account for variability in individual cingulate morphology. The results demonstrated a rostro-caudal functional organization of the CMAs in the human brain that parallels that in the lateral frontal cortex: the rostral CMA has stronger functional connectivity with prefrontal regions and weaker connectivity with motor regions; conversely, the more caudal CMAs have weaker prefrontal and stronger motor connectivity. Connectivity patterns of the hand, tongue and eye representations within the CMAs are consistent with that of their parent CMAs. The parallel rostral-to-caudal functional organization observed in the medial and lateral frontal cortex could likely contribute to different hierarchies of cognitive-motor control. [ABSTRACT FROM AUTHOR]

Objectives: Body dysmorphic disorder (BDD) is characterized by repetitive behaviors and/or mental acts occurring in response to preoccupations with perceived defects or flaws in physical appearance. There are some similarities, but also important differences, between BDD and obsessive-compulsive disorder (OCD), not just in terms of core clinical symptoms, but possibly in the domain of perception. This study compared the nature and extent of perceptual anomalies in BDD versus OCD and health controls (HC), using a modified Mooney task. Methods: We included 21 BDD, 19 OCD, and 21 HC participants, who were age-, sex-, and IQ-matched. A set of 40 Mooney faces and 40 Mooney objects arranged in three configurations (i.e., upright, inverted, or scrambled) were presented under brief (i.e., 500 ms) free-viewing conditions. Participants were asked to decide whether each image represented a human face, an object, or neither in a forced-choice paradigm. Results: The BDD group showed significantly reduced face and object inversion effects relative to the other two groups. This was accounted for by BDD participants being significantly more accurate in identifying inverted Mooney faces and objects than the other participants. Conclusions: These data were interpreted as reflecting an overreliance on independent components at the expense of holistic (configural) processing in BDD. (JINS, 2017, 23, 471–480) [ABSTRACT FROM PUBLISHER]

Introduction: Attention-deficit/hyperactivity disorder (ADHD) and anxiety are frequently comorbid disorders associated with different types of abnormal performance on neuropsychological tests. Although some studies have shown that comorbid anxiety alters ADHD test performance, results inconsistently show both improvements and worsening of different abilities, with failures to replicate across different anxiety disorders. Alternatively, trait anxiety may reflect a more stable influence on ADHD test performance than various diagnosable anxiety disorders.Method: To better understand the possible enhancing or deleterious effects of anxiety on ADHD cognitive impairments, this study examined the effect of individual differences in trait anxiety measured by the Multidimensional Anxiety Scale for Children (MASC) on a battery of computerized, rapid-performance tests measuring attention and impulsivity-related performance in 98Diagnostic and Statistical Manual of Mental Disorders–Fourth Edition(DSM–IV) Combined-Subtype ADHD adolescents and 123 healthy controls. It was hypothesized that trait anxiety would attenuate response inhibition and attention deficits in ADHD.Results: ADHD-diagnosed adolescents with higher trait anxiety performed better on indices of sustained attention, reaction time, and motor variability, and had altered overall test-performance strategy, while response inhibition was affected in both ADHD and non-ADHD.Conclusions: This study provides the first evidence that pathological levels of anxiety are not needed to see differences in ADHD neuropsychological test performance. Instead, mildly elevated trait anxiety confers a protective influence by reducing the degree of impairment seen in ADHD. These findings suggest that better performing ADHD adolescents might have optimized levels of cortical arousal, and raise new questions about how best to identify the neurobiological substrates responsible for the beneficial effects. [ABSTRACT FROM PUBLISHER]

Behavioral and brain responses to stimuli not only depend on their physical features but also on the individuals' neurocognitive states before stimuli onsets. While the influence of pre-stimulus fluctuations in brain activity on low-level perceptive processes is well established, the state dependency of high-order executive processes remains unclear. Using a classical inhibitory control Go/NoGo task, we examined whether and how fluctuations in the brain activity during the period preceding the stimuli triggering inhibition influenced inhibitory control performance. Seventeen participants completed the Go/NoGo task while 64-channel electroencephalogram was recorded. We compared the event-related potentials preceding the onset of the NoGo stimuli associated with inhibition failures false alarms ( FA) vs. successful inhibition correct rejections ( CR) with data-driven statistical analyses of global measures of the topography and strength of the scalp electric field. Distributed electrical source estimations were used to localize the origin of the event-related potentials modulations. We observed differences in the global field power of the event-related potentials ( FA > CR) without concomitant topographic modulations over the 40 ms period immediately preceding NoGo stimuli. This result indicates that the same brain networks were engaged in the two conditions, but more strongly before FA than CR. Source estimations revealed that this effect followed from a higher activity before FA than CR within bilateral inferior frontal gyri and the right inferior parietal lobule. These findings suggest that uncontrolled quantitative variations in pre-stimulus activity within attentional and control brain networks influence inhibition performance. The present data thereby demonstrate the state dependency of cognitive processes of up to high-order executive levels. [ABSTRACT FROM AUTHOR]

This is a focused review of imaging literature to scope the utility of hybrid brain imaging in neuropsychiatric disorders. The review focuses on brain imaging modalities that utilize hybrid (fusion) techniques to characterize abnormal brain molecular signals in combination with structural and functional changes that have been observed in neuropsychiatric disorders. An overview of clinical hybrid brain imaging technologies for human use is followed by a selective review of the literature that conceptualizes the use of these technologies in understanding basic mechanisms of major neuropsychiatric disorders and their therapeutics. Neuronal network abnormalities are highlighted throughout this review to scope the utility of hybrid imaging as a potential biomarker for each disorder. [ABSTRACT FROM AUTHOR]

In the past few decades, the prevalence of obesity and type 2 diabetes mellitus (T2DM), as well as older individuals at risk for Alzheimer's disease (AD), has increased. While the consumption of diets high in fat (total and saturated) have been linked to increased risk of AD, diets rich in antioxidants, polyunsaturated fats, and omega-3 fatty acids are associated with decreased risk. Additionally, AD patients are at increased risk for developing T2DM. Recent research suggests that there are stronger similarities between AD and T2DM than have previously been considered. Here we review the neurocognitive and inflammatory effects of high-fat diet consumption, its relationship to AD, and the treatment potential of dietary interventions that may decrease risk of cognitive decline and other associated neuropathological changes, such as insulin resistance, oxidative stress, and chronic inflammatory processes. [ABSTRACT FROM AUTHOR]

Intermittent hypoxia has generally been perceived as a high-risk stimulus, particularly in the field of sleep medicine, because it is thought to initiate detrimental cardiovascular, respiratory, cognitive, and metabolic outcomes. In contrast, the link between intermittent hypoxia and beneficial outcomes has received less attention, perhaps because it is not universally understood that outcome measures following exposure to intermittent hypoxia may be linked to the administered dose. The present review is designed to emphasize the less recognized beneficial outcomes associated with intermittent hypoxia. The review will consider the role intermittent hypoxia has in cardiovascular and autonomic adaptations, respiratory motor plasticity, and cognitive function. Each section will highlight the literature that contributed to the belief that intermittent hypoxia leads primarily to detrimental outcomes. The second segment of each section will consider the possible risks associated with experimentally rather than naturally induced intermittent hypoxia. Finally, the body of literature indicating that intermittent hypoxia initiates primarily beneficial outcomes will be considered. The overarching theme of the review is that the use of intermittent hypoxia in research investigations, coupled with reasonable safeguards, should be encouraged because of the potential benefits linked to the administration of a variety of low-risk intermittent hypoxia protocols. [ABSTRACT FROM AUTHOR]

The subjective value of rewards declines the longer rewards are delayed into the future ('delay discounting'). Discounting behavior varies both as a function of an individual's trait and current state. The degree of discounting has repeatedly been associated with relapse following treatment of addiction. Therefore, the effects of acute drug deprivation on discounting processes are potentially of high clinical relevance. In two testing sessions (24 hr of nicotine deprivation vs. normal smoking) 37 heavy smoking participants made choices between immediate and delayed rewards as well as between shorter and longer delayed rewards. We found no evidence for an effect of nicotine deprivation on delay discounting of potentially real monetary rewards in both types of decision tasks. Although choice stochasticity was numerically increased after deprivation, this effect was not significant (p > .1). Participants responded significantly slower after nicotine deprivation. Our study supports previous findings that choice impulsivity as measured using discounting tasks is not affected by nicotine deprivation, at least not if real monetary rewards of lower amounts are at stake. [ABSTRACT FROM AUTHOR]

Cognition and motor performance are essential components of human functioning. Recent research has provided evidence that these two domains are more interrelated than previously thought. This is a potentially important area of research with many questions that warrant further exploration and have practical implications to the field of neurological rehabilitation. In this review of literature we included animals and humans in healthy conditions as well as pathological conditions affecting the central nervous system. Our primary goal was to comprehensively review the relevant basic science and clinical literature on the effects of motor interventions on cognitive function and vice versa. We found more evidence supporting positive effects of exercise on cognition than effects of cognitive training on motor function. In addition, we examined the extent to which findings from animal literature have been or can be translated to humans. We found that, with the exception of one study in monkeys, most animal studies which investigate rodents are somewhat challenging to translate to human studies, independent of the intervention employed. It is difficult to find a human parallel to exercise in rodents, because both the voluntary and forced exercise paradigms used in rodents happen in a different context than humans. In addition it is difficult to find an animal parallel to cognitive training in humans, because the environmental enrichment intervention cannot be considered 'purely' cognitive stimulation as it also involves sensory, motor and social components. We conclude the review by suggesting avenues for future research and intervention strategies. [ABSTRACT FROM AUTHOR]

Background: ABT-288, a highly selective histamine-3 receptor antagonist, demonstrated efficacy across several preclinical cognitive domains, and safety in healthy subjects and elderly volunteers. Objective: Evaluate the efficacy and safety of ABT-288 in subjects with mild-to-moderate Alzheimer's dementia. Methods: The study used a randomized, double-blind, placebo- and active-controlled, parallel group design with pre-defined futility criteria to permit early study termination. A total of 242 subjects were randomized in an equal ratio to ABT-288 1 mg or 3 mg, donepezil 10 mg, or placebo once daily for 12 weeks. The primary efficacy endpoint was the change from baseline to final evaluation on the 13-item Alzheimer's Disease Assessment Scale-cognitive subscale (ADAS-Cog) total score. Results: The study was prematurely terminated because futility criteria were met. Point estimates on the ADAS-Cog scores for both ABT-288 dose groups were numerically inferior to placebo but no statistical differences were detected. Donepezil demonstrated statistically significant improvement. Adverse events were generally mild and self-limiting. Conclusion: ABT-288 did not demonstrate efficacy in the symptomatic treatment of Alzheimer's dementia. [ABSTRACT FROM AUTHOR]

No studies have identified the direct effect of changes in cerebral blood flow ( CBF) on cognitive function at rest and during exercise. In this study, we manipulated CBF using hypercapnic gas to examine whether an increase in CBF improves cognitive function during prolonged exercise. The speed and the accuracy of cognitive function were assessed using the Stroop color-word test. After the Stroop test at rest, the subjects began exercising on a cycling ergometer in which the workload was increased by 0.5 kilopond every minute until a target heart rate of 140 beats/min was achieved. Then, the subjects continued to cycle at a constant rate for 50 min. At four time points during the exercise (0, 10, 20, 50 min), the subjects performed a Stroop test with and without hypercapnic respiratory gas (2.0% CO2), with a random order of the exposures in the two tests. Despite a decrease in the mean blood flow velocity in the middle cerebral artery ( MCA Vmean), the reaction time for the Stroop test gradually decreased during the prolonged exercise without any loss of performance accuracy. In addition, the hypercapnia-induced increase in MCA Vmean produced neither changes in the reaction time nor error in the Stroop test during exercise. These findings suggest that the changes in CBF are unlikely to affect cognitive function during prolonged exercise. Thus, we conclude that improved cognitive function may be due to cerebral neural activation associated with exercise rather than global cerebral circulatory condition. [ABSTRACT FROM AUTHOR]

Amylin, a gut-brain axis hormone, and amyloid-beta peptides (Aβ), a major component of the Alzheimer's disease (AD) brain, share several features, including similar β-sheet secondary structures, binding to the same receptor and being degraded by the same protease, insulin degrading enzyme (IDE). However, while amylin readily crosses the blood brain barrier (BBB) and mediates several activities including improving glucose metabolism, relaxing cerebrovascular structure, modulating inflammatory reaction and perhaps enhancing neural regeneration, Aβ has no known physiological functions. Thus, abundant Aβ in the AD brain could block or interfere with the binding of amylin to its receptor and hinder its functions. Recent studies using animal models for AD demonstrate that amylin and its analog reduce the AD pathology in the brain and improve cognitive impairment in AD. Given that, in addition to amyloid plaques and neurofibrillary tangles, perturbed cerebral glucose metabolism and cerebrovascular damage are the hallmarks of the AD brain, we propose that giving exogenous amylin type peptides have the potential to become a new avenue for the diagnosis and therapeutic of AD. Although amylin's property of self-aggregation may be a limitation to developing it as a therapeutic for AD, its clinical analog, pramlintide containing 3 amino acid differences from amylin, does not aggregate like human amylin, but more potently mediates amylin's activities in the brain. Pramlintide is an effective drug for diabetes with a favorable profile of safety. Thus a randomized, double-blind, placebo-controlled clinical trial should be conducted to examine the efficacy of pramlintide for AD. This review summarizes the knowledge and findings on amylin type peptides and discuss pros and cons for their potential for AD. [ABSTRACT FROM AUTHOR]

Background: Both cognitive and physical exercise have been discussed as promising interventions for healthy cognitive aging. The present study assessed the effects of cognitive training (spatial vs. perceptual training) and physical training (endurance training vs. non-endurance training) on spatial learning and associated brain activation in 33 adults (40-55 years). Spatial learning was assessed with a virtual maze task, and at the same time neural correlates were measured with functional magnetic resonance imaging (fMRI). Results: Only the spatial training improved performance in the maze task. These behavioral gains were accompanied by a decrease in frontal and temporal lobe activity. At posttest, participants of the spatial training group showed lower activity than participants of the perceptual training group in a network of brain regions associated with spatial learning, including the hippocampus and parahippocampal gyrus. No significant differences were observed between the two physical intervention groups. Conclusions: Functional changes in neural systems associated with spatial navigation can be induced by cognitive interventions and seem to be stronger than effects of physical exercise in middle-aged adults. [ABSTRACT FROM AUTHOR]

BACKGROUND: Catechin-rich oil palm ( Elaeis guineensis) leaf extract (OPLE) has good cardiovascular and phytoestrogenic properties. The OPLE (0.5 g day−1) was supplemented to young, healthy, adult human volunteers, and their cognitive learning abilities were compared to placebo-controlled groups ( N = 15). Their short-term memories, spatial visualisations, processing speeds, and language skills, were assessed over 2 months by cognitive tests computer programs. RESULTS: Relative to the controls, volunteers taking OPLE had improved ( P < 0.05) short-term memory, after 1 month of intervention which became highly significant ( P < 0.005) after 2 months. The spatial visualisation ability and processing speed improved ( P < 0.05) after 2 months consumption. The dietary OPLE showed neuroprotection in nitric oxide-deficient rats. The mechanisms involved systemic and cellular modulations that eventually enhance neuron survival. The longer the duration of OPLE consumption, the more significant was the enhancement, as shown for short-term memory. CONCLUSION: This is the first report on the cognitive-enhancing effects of dietary OPLE in humans. The computer-assisted cognitive tests were simple, low in cost, errors and man hours, and hence are better than conventional cognitive test methods. In rats, the equivalent OPLE dose showed brain antioxidant enzymes modulating properties and neuroprotection under nitric oxide deficiency, with possibly neurogenesis in normal rats. This supported the effects in humans. © 2012 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Human genetic association studies in individuals with traumatic brain injury (TBI) have increased rapidly over the past few years. Recently, several review articles evaluated the association of genetics with outcomes after TBI. However, almost all of the articles discussed in these reviews focused on adult TBI. The primary objective of this review is to gain a better understanding of which genes and/or genetic polymorphisms have been evaluated in pediatric TBI. Our initial search identified 113 articles. After review of these articles only 5 genetic association studies specific to pediatric TBI were identified. All five of these studies evaluated the apolipoprotein (APOE) gene. The study design and methods of these identified papers will be discussed. An additional search was then performed to evaluate genes beyond APOE that have been evaluated in adult TBI; findings from these studies are highlighted. Larger genetic studies will need to be performed in the future to better elucidate the association of APOE and other genes with outcomes after TBI in children. There is great potential to utilized genetic information to inform prognosis and management after TBI in children; however, we have much work ahead of us to reach the goal of individualized management. [ABSTRACT FROM AUTHOR]

The Iowa Gambling Task (IGT) is a measure of decision-making, in which alternative metrics have greater construct validity than conventional metrics. No large scale study has examined the neural correlates in healthy adults. We administered the IGT and structural MRI to 124 healthy participants. We analyzed the conventional IGT metric of advantageous minus disadvantageous choices (i.e., decks C + D minus decks A + B), and three alternative metrics based on choices from decks D and A alone, and all selections from each deck. Using regression and voxel-based morphometry, we examined regional gray matter volumes as predictors of IGT performance. No neural correlates of the conventional metric emerged, and the neural correlates of individual deck selections were disparate from one another. Alternative metrics showed expected neural correlates of decision-making in prefrontal cortex, insula, thalamus, and other regions. IGT alternative metrics have neural correlates consistent with decision-making theory as those difference scores reduce heterogeneity in cognitive processes. The CD-AB metric construct failure may reflect an artificial amalgamation of processes. The D-A metric appears to more successfully combine multiple levels of representation (dorsolateral prefrontal cortex, sub-cortical, cerebellar). (JINS, 2012, 18, 585–594) [ABSTRACT FROM AUTHOR]

The 20th century brought with it the so-called club drugs (the most notorious being amphetamine derivatives), which are used by young adults at all-night dance parties. Methamphet­amine and 3,4-methylenedioxymethamphetamine (MDMA or ecstasy) are synthetic drugs with stimulant and psychoactive properties that belong to the amphetamine family. Here, we have reviewed the literature about the cognitive impairment induced by these two amphetamine derivatives and the preclinical and clinical outcomes. Although there is controversial evidence about the effect of methamphetamine and MDMA on learning and memory in laboratory animals, results from published papers demonstrate that amphetamines cause long-term impairment of cognitive functions. A large number of pharmacological receptors have been studied and screened as targets of amphetamine-induced cognitive dysfunction, and extensive research efforts have been invested to provide evidence about the molecular mechanisms behind these cognitive deficits. In humans, there is a considerable body of evidence indicating that methamphetamine and MDMA seriously disrupt memory and learning processes. Although an association between the impairments of memory performance and a history of recreational amphetamine ingestion has also been corroborated, a number of methodological difficulties continue to hamper research in this field, the most important being the concomitant use of other illicit drugs. [ABSTRACT FROM AUTHOR]

The role of serotonin (5-HT) in attention is not fully understood yet. We aimed to investigate whether attention is modulated after treatment with escitalopram, a selective serotonin reuptake inhibitor (SSRI). We administered 10 mg of escitalopram to 20 healthy subjects in a placebo-controlled, double-blind cross-over design for 1 day or to another 20 participants for a period of 7 days. Attention was assessed at time of plasma peak escitalopram concentration using the computerised Attention Network Test (ANT), which is a combined flanker and cued reaction time task. The results showed differential effects of serotonergic manipulation on attention depending on sequence of intake. For the acute treatment, we found significant differences between escitalopram and placebo for all warning conditions dependent of sequence of intake: participants receiving escitalopram as first treatment showed significant slower reaction times in all warning conditions as compared with placebo while participants receiving escitalopram as second treatment showed significant faster reaction times as compared with placebo. For the sub-chronic treatment, we found significant differences between escitalopram and placebo depending on sequence of intake, but only for the flanker condition: participants receiving escitalopram first had significant slower reaction times in incongruent trials with escitalopram as compared with placebo while participants starting with placebo had significant shorter reaction times in incongruent trials with escitalopram. Thus, the results showed a differential effect of escitalopram in cognition, especially in attention, and are discussed with regard to an interaction between serotonin and familiarity with the attention test. [ABSTRACT FROM AUTHOR]

The ability to maintain information online beyond sensory stimulation is regarded as a key contribution of working memory to goal-directed behaviour. It is widely accepted that sustained neural activity is a key mechanism of stimulus maintenance, but it is unclear to what extent the neural generators of sustained activity change from stimulus-encoding to maintenance. Using event-related potentials in humans, we show that, in a delayed match-to-sample task, slow shifts over parieto-occipital electrode sites had a different topography and polarity during encoding and delay maintenance of images depicting scenes. This clearly demonstrates that neural generators of sustained activity associated with stimulus-encoding and delay maintenance differed, and that the change between these generators occurred time-locked to the onset of the delay period. We also investigated how monetary reward incentives modulated the amplitude and topography of sustained delay activity and the ability to suppress irrelevant distracting information during the delay. Reward incentives improved maintenance performance and this was correlated with an expansion of the parieto-occipital electrode sites that were entrained into sustained delay activity (rather than improved distractor suppression), suggesting that under the influence of reward, the parieto-occipital regions that contributed to delay maintenance expanded in size. [ABSTRACT FROM AUTHOR]

The article presents abstracts on medical topics which include hormone therapy and the brain, healthy cell bias of estrogen action and brain selective estrogen alternatives, and critical period hypothesis of estrogen effects on cognition.