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Resting state functional Magnetic Resonance Imaging (RS-fMRI) provides the means to measure neuronal activity. One of the most commonly used methods to explore the RS-fMRI signal is the Probabilistic Independent Component Analysis (PICA). PICA allows to depict brain functional connectivity (FC) networks. Yet most of the IC maps obtained with this method do not represent any particular FC network. Consequently, those IC maps are classified as artifacts or noise of an unknown source. We hypothesized that the unexplained RS-fMRI signal patterns that are picked up by the PICA can be related to the differences in oxygen metabolism and blood flow in cortical layers. This study aimed at (1) providing preliminary evidence to the effects of laminar organization of neocortex on the RS-fMRI signal, and (2) evaluating the application of laminar maps to aid the classification of IC maps. We created laminar maps 1-4 that depict relative cortical thickness of layers IV and VI. Our data show that the RS-fMRI signal is significantly related to the relative thickness of the cortical layer VI but not layer IV. Importantly, the laminar maps 1-4 overlap with four separate IC maps. Thus, the laminar maps 1-4 improve classification and interpretation of the IC maps. Moreover, the laminar maps 1-4 may be considered as FC networks that are the bridging piece between particular cognitive functions. Together, these data provide preliminary evidence to the fundamental questions about the role of cortical layering in the RS-fMRI signal and brain FC networks.

Highlights • About a third of patients with neuroimaging in acute/subacute phase show brain abnormalities suggestive of COVID-19 etiology. • Cerebral white matter hyperintensities/hypodensities comprise the primary neuroimaging feature in COVID-19 patients. • Brain abnormalities are diffused across the cerebral hemispheres rather than region-specific., Objective This systematic review aimed to synthesize early data on typology and topography of brain abnormalities in adults with COVID-19 in acute/subacute phase. Methods We performed systematic literature search via PubMed, Google Scholar and ScienceDirect on articles published between January 1 and July 05, 2020, using the following strategy and key words: ((covid[Title/Abstract]) OR (sars-cov-2[Title/Abstract]) OR (coronavirus[Title/Abstract])) AND (brain[Title/Abstract]). A total of 286 non-duplicate matches were screened for original contributions reporting brain imaging data related to SARS-Cov-2 presentation in adults. Results The selection criteria were met by 26 articles (including 21 case reports, and 5 cohort studies). The data analysis in a total of 361 patients revealed that brain abnormalities were noted in 124/361 (34%) reviewed cases. Neurologic symptoms were the primary reason for referral for neuroimaging across the studies. Modalities included CT (-angiogram, -perfusion, -venogram), EEG, MRI (-angiogram, functional), and PET. The most frequently reported brain abnormalities were brain white matter (WM) hyperintensities on MRI 66/124 (53% affected cases) and hypodensities on CT (additional 23% affected cases), followed by microhemorrhages, hemorrhages and infarcts, while other types were found in

INTRODUCTION Cortical thinning is associated with aging; however, lifestyle factors can moderate this relationship. Two distinct lifestyle behaviors associated with brain health are regular moderate-to-vigorous physical activity (MVPA) and limited sedentary behavior (SB). However, it is unclear whether MVPA and SB levels contribute to cortical thickness independent of each other. We therefore investigated the independent relationships of MVPA and SB with cortical thickness using baseline data from a randomized controlled trial. METHODS At baseline, we measured MVPA and SB for 7 d using the SenseWear Mini. A subset of the randomized controlled trial participants (n = 30) underwent a 3T magnetic resonance imaging scan, wherein region-specific cortical surface morphometric analyses were performed using T1-weighted structural magnetic resonance imaging. We conducted regression analyses using a surface-based cluster size exclusion method for multiple comparisons within FreeSurfer neuroimaging software to determine if MVPA and SB are independently correlated with region-specific cortical thickness. RESULTS This subset of participants had a mean age of 61 yr (SD = 9 yr), and 80% were female. Higher MVPA was associated with greater cortical thickness in the temporal pole (cluster size, 855 mm; cortical thickness range, 2.59-3.72 mm; P < 0.05) and superior frontal gyrus (cluster size, 1204 mm; cortical thickness range, 2.41-3.15 mm; P < 0.05) of the left hemisphere, independent of SB. Sedentary behavior was not associated with greater cortical thickness in any region, independent of MVPA. CONCLUSIONS Our results indicate that adults with greater MVPA-independent of SB-are associated with greater cortical thickness in regions, which are susceptible to age-associated atrophy.

Objective:To propose a set of internationally harmonized procedures and methods for assessing neurocognitive functions, smell, taste, mental, and psychosocial health, and other factors in adults formally diagnosed with COVID-19 (confirmed as SARS-CoV-2 + WHO definition).Methods:We formed an international and cross-disciplinary NeuroCOVID Neuropsychology Taskforce in April 2020. Seven criteria were used to guide the selection of the recommendations’ methods and procedures: (i) Relevance to all COVID-19 illness stages and longitudinal study design; (ii) Standard, cross-culturally valid or widely available instruments; (iii) Coverage of both direct and indirect causes of COVID-19-associated neurological and psychiatric symptoms; (iv) Control of factors specifically pertinent to COVID-19 that may affect neuropsychological performance; (v) Flexibility of administration (telehealth, computerized, remote/online, face to face); (vi) Harmonization for facilitating international research; (vii) Ease of translation to clinical practice.Results:The three proposed levels of harmonization include a screening strategy with telehealth option, a medium-size computerized assessment with an online/remote option, and a comprehensive evaluation with flexible administration. The context in which each harmonization level might be used is described. Issues of assessment timelines, guidance for home/remote assessment to support data fidelity and telehealth considerations, cross-cultural adequacy, norms, and impairment definitions are also described.Conclusions:The proposed recommendations provide rationale and methodological guidance for neuropsychological research studies and clinical assessment in adults with COVID-19. We expect that the use of the recommendations will facilitate data harmonization and global research. Research implementing the recommendations will be crucial to determine their acceptability, usability, and validity.

Stroke survivors undergo a thorough cognitive diagnosis that often involves administration of multiple standardized tests. However, patient’s narrative discourse can provide clinicians with additional knowledge on patient’s subjective experience of illness, attitude toward current situation, and motivation for treatment. We evaluated the methods of analyzing thematic content and story types in relationship to cognitive impairment in stroke survivors with no aphasia (including 9 left hemisphere damage – LHD patients, and 16 right hemisphere damage – RHD patients). Cognitive impairment was evaluated in comparison to a group of 25 patients with orthopaedic injury not involving the brain. Our findings primarily show that higher elaboration on own cognitive problems, physical ailments or coping strategies in LHD patients and cognitive problems, emotional issues and circumstances of illness onset in RHD patients is related to deficits in executive functions and retrieval of information from memory. Furthermore, RHD patients who use more chaos story type show lower executive functioning. However, these results did not survive the significance threshold of p < 0.05 after Bonferroni adjustment for multiple comparisons. In conclusion, this study provides preliminary evidence that stroke survivor’s narrative can constitute an additional source of clinically-relevant information regarding patient’s experience of illness and attitude toward recovery. This knowledge can aid clinicians and nurses in everyday interactions with the patients and support individualized strategy to treatment. Still, the current results need be confirmed with future studies in a larger cohort of stroke patients.

It is yet unclear if people infected with human immunodeficiency virus (HIV+) on stable, combined antiretroviral therapies (cARTs) decline with age at the same or greater rate than healthy people. In this study, we examined independent and interactive effects of HIV, age, and HIV-related clinical parameters on neuropsychological functioning and brain regional volume in a sizable group of Polish HIV+ men receiving cART. We also estimated the impact of nadir CD4 cell count, CD4 cell count during participation in the study, duration of HIV infection, or duration of cART along with age. Ninety-one HIV+ and 95 control (HIV−) volunteers ages 23–75 completed a battery of neuropsychological tests, and 54 HIV+ and 62 HIV− of these volunteers participated in a brain imaging assessment. Regional brain volume in the cortical and subcortical regions was measured using voxel-based morphometry. We have found that HIV and older age were independently related to lower attention, working memory, nonverbal fluency, and visuomotor dexterity. Older age but not HIV was associated with less volume in several cortical and subcortical brain regions. In the oldest HIV+ participants, age had a moderating effect on the relationship between the duration of cART and visuomotor performance, such as that older age decreased speed of visuomotor performance along with every year on cART. Such results may reflect the efficacy of cART in preventing HIV-associated brain damage. They also highlight the importance of monitoring neuropsychological functioning and brain structure in HIV+ patients. This is particularly important in older patients with long adherence to cART. Electronic supplementary material The online version of this article (10.1007/s13365-018-0679-4) contains supplementary material, which is available to authorized users.

The aim of this study was to further elucidate the relationship between the olfactory system and psychosocial functioning. Previous studies have shown that olfactory sensitivity is related to traits such as extraversion, agreeableness, and emotionality. In this study, the model of agency and communion as well as additional measures of social activity were used. The possible influence of HIV infection, believed to affect both chemosensory functions and social behaviors, was examined. 103 male participants were analyzed, of whom 45 were infected with HIV. Olfactory sensitivity was significantly related to the level of communion (p = .01), trait defined as interpersonal warmth, devotion to others, and morality. The effect was independent of the presence of HIV. Eagerness to engage in social activities, a construct indicating how actively one takes part in social life, was positively associated with olfactory sensitivity only in HIV+ individuals (p = .003). This result may imply that active participation in social life can buffer olfactory impairments in HIV patients.

Objective Findings on the influence of age and HIV on brain and cognition remain equivocal, particularly in aviremic subjects without other age or HIV-related comorbidities. We aimed to (a) examine the effect of HIV status and age on structural brain measurements and cognition, and (b) apply the machine learning technique to identify brain morphometric and cognitive features that are most discriminative between aviremic subjects with HIV on stable combination antiretroviral therapy (cART) and healthy controls. Method Fifty-three HIV-seropositive patients and 62 healthy controls underwent neuropsychological testing (executive functions, attention, memory, learning, psychomotor speed, fluency) and volumetric MRI scans. Voxel-based morphometry, ANCOVAs, machine learning, and multivariate regression were conducted to determine the between group differences in terms of relationship of HIV status, age, and their interaction on neurocognitive and structural brain measures. Results Volume and gray matter (GM) thickness of the caudate, parahippocampus, insula, and inferior frontal gyrus were smaller in seropositive subjects in comparison with healthy controls (HC). They also performed worse in complex attention and cognitive fluency tasks. Support vector machine (SVM) analysis revealed that the best between-groups classification accuracy was obtained based on cognitive scores encompassing complex attention and psychomotor speed, as well as volumetric measures of white matter and total gray matter; third, fourth, and lateral ventricles; amygdala; caudate; and putamen. Both voxel-based morphometry (VBM) and regression analysis yielded that HIV and aging independently increase brain vulnerability and cognitive worsening. Conclusion Patients with HIV on effective cART demonstrate smaller volumetric measures and worse cognitive functioning relative to seronegative individuals. There is no interaction between HIV infection and aging. (PsycINFO Database Record (c) 2019 APA, all rights reserved).

Poor sleep quality, decreased physical activity (PA) and increased sedentary behavior (SB) are common characteristics of older adults. Notably, these factors play an important role in brain health. We examined the relationship between sleep quality, PA, SB and brain white matter integrity (WM) in older adults with osteoarthritis (OA). We retained data on 16 participants (mean age 60, SD=7.7) from a larger Monitor-OA cohort recruited from Metro Vancouver, BC, Canada. Sleep efficiency and duration, amount of time spent on PA and SB daily over a period of one week was acquired with an objective measure – the multi-sensor monitor SenseWear Mini which integrates tri-axial accelerometer data, physiological sensor data and personal demographic information. Brain WM tractography was calculated from fractional anisotropy data obtained with diffusion weighted magnetic resonance imaging. Voxelwise group-level statistics examined the effects of our variables of interest on the integrity of brain WM tracts while controlling for participants age. We found that lower sleep efficiency was related to decreased integrity in WM tracts of frontal, temporal lobes, precuneus and thalamus (Bonferroni corrected p

The objective of the study was to examine additive and synergistic effects of age and HIV infection on resting state (RS) intra- and inter-network functional connectivity (FC) of the brain. We also aimed to assess relationships with neurocognition and determine clinical-, treatment-, and health-related factors moderating intrinsic brain activity in aging HIV-positive (HIV+) individuals. The current report presents data on 54 HIV+ individuals (age M = 41, SD = 12 years) stabilized on cART and 54 socio-demographically matched healthy (HIV−) comparators (age M = 43, SD = 12 years), with cohort education mean of 16 years (SD = 12). Age at seroconversion ranged 20–55 years old. ANOVA assessed additive and synergistic effects of age and HIV in 133 ROIs. Bivariate statistics examined relationships of FC indices vulnerable to age-HIV interactions and neurocognitive domains T-scores (attention, executive, memory, psychomotor, semantic skills). Multivariate logistic models determined covariates of FC. This study found no statistically significant age-HIV effects on RS-FC after correcting for multiple comparisons except for synergistic effects on connectivity within cingulo-opercular network (CON) at the trending level. However, for uncorrected RS connectivity analyses, we observed HIV-related strengthening between regions of fronto-parietal network (FPN) and default mode network (DMN), and particular DMN regions and sensorimotor network (SMN). Simultaneously, FC weakening was observed within FPN and between other regions of DMN-SMN, in HIV+ vs. HIV- individuals. Ten ROI pairs revealed age-HIV interactions, with FC decreasing with age in HIV+, while increasing in controls. FC correlated with particular cognitive domains positively in HIV+ vs. negatively in HIV- group. Proportion of life prior-to-after HIV-seroconversion, post-infection years, and treatment determined within-FPN and SMN-DMN FC. In sum, highly functioning HIV+/cART+ patients do not reveal significantly altered RS-FC from healthy comparators. Nonetheless, the current findings uncorrected for multiple comparisons suggest that HIV infection may lead to simultaneous increases and decreases in FC in distinct brain regions even in patients successfully stabilized on cART. Moreover, RS-fMRI ROI-based analysis can be sensitive to age-HIV interactions, which are especially pronounced for inter-network FC in relation to neurocognition. Aging and treatment-related factors partially explain RS-FC in aging HIV+ patients.

This study examined the effects of age and HIV infection on the resting state (RS) functional connectivity (FC) of the brain and cognitive functioning. The objective was to evaluate the moderating role of age and HIV on the relationship between RS-FC and cognition. To examine RS-FC we implemented the Independent Component Analysis (ICA) and Regional Homogeneity (ReHo). Neurocognition was evaluated with comprehensive battery of standardized neuropsychological tests. Age and HIV were entered as the independent variables. The independent effects of age, HIV, and interaction effects of age-HIV on RS-fMRI measures (ICA, ReHo) were tested in 108 participants (age M = 42). RS-FC indices that exhibited age-HIV interactions were entered into further analysis. Bivariate correlation analysis was performed between the retained RS-FC indices and T-scores of neurocognitive domains (Attention, Executive, Memory, Psychomotor, Semantic Skills). Multivariate regression modeling determined the impact of age and HIV on these relationships. We found that in the ICA measures, HIV-seropositivity was decreasing RS-FC in the left middle occipital gyrus (p < .001). Age-HIV interaction was observed in the left superior frontal gyrus (LSupFrontG), where FC was decreasing with age in HIV+ (p < .001) and increasing in HIV- (p = .031). ReHo indices did not reveal significant effects. HIV strengthened the relationship between RS-FC in LSupFrontG, Memory and Psychomotor Factor scores. Aging weakened those relationships only in control group. In sum, age-HIV interaction effects are prominent rather in remote than local RS-FC. Seroconversion strengthens relationships between intrinsic brain activity and neurocognition, but no acceleration with years of age was noted in HIV+ individuals.

Older adults with mild cognitive impairment (MCI) are at an elevated risk of falls. We conducted a pilot longitudinal observational study to examine the natural course of brain intrinsic functional connectivity (FC) and cognitive function changes in association to falling history in older adults with MCI. 15 MCI participants (mean age 75.9, range 67-86) included 10 non-fallers and 5 fallers (minimum two falls in the previous 12 months with one in the last 6 months) from Metro Vancouver, BC, Canada. At study entry and 1-year follow-up, participants completed brain scanning session of structural MRI and resting state (RS) functional MRI, the Montreal Cognitive Assessment (MoCA), and the Mini Mental State Examination (MMSE). Results indicated an interaction between time (baseline vs. follow-up) and falls history on RS-FC in individuals with MCI (p

Individuals in the early stages of dementia may demonstrate language difficulties. The aim of the study was an evaluation of the differences in narrative discourse abilities across two types of dementia, i.e., Vascular Dementia (VaD) and Alzheimer’s Disease (AD) in comparison to the young and old elderly. The AD and VaD groups displayed a lower performance than the age-matched YE on tasks involving reasoning. The VaD partici- pants outperformed patients with AD in verbal memory and narrative discourse. Discourse macrostructure analyses showed that the VaD reproduced more propositions than did the AD participants, but that these were comparable to YE and OE. There were more conjunctions in narratives reproduced by the VaD participants as compared to other groups, although this tendency was only present in the story but not in fairy tale reproductions themselves. Individ- uals in the AD group had more difficulties than YE and OE individuals in figuring out the moral of fairy tales. Clinical and control groups reproduced the microstructure and superstructure of texts comparatively well. Discourse recall correlated with performance on verbal memory, attention/working memory, and reasoning. Differences in narrative discourse abilities were found. Alzheimer’s Disease (AD) patients scored lower in verbal memory than did Vascular Dementia (VaD) patients. Both groups however obtained lower results than the young and old elderly.