Magister Public Health - MPH / Despite the effectiveness and scale-up of antiretroviral treatment (ART), HIV-Associated neurocognitive disorders (HAND) still persist. Currently no gold standard tool exists to detect all forms of HAND, including major and minor cognitive impairments. In light of this, a newly developed screening tool was conceptualised, namely the Quick Paediatric Neurocognitive Screening tool (QPNST). The QPNST has been developed to detect HAND in perinatally HIV-infected children aged 5-10 years.

The objective of the present study was to evaluate the relationship between a set of cofactors and severity of cognitive impairment, to determine if there were any factors which significantly predicted more severe neurocognitive deficits in persons with AIDS. Twenty-four male volunteers recruited from community groups and physician referrals participated. Subjects completed several self-report questionnaires eliciting information regarding demographics and risk factor variables, in addition to a comprehensive battery of neuropsychological tests. A severity of cognitive impairment summary score was computed for each subject, reflecting both the number of impaired tests and their distance in the impaired direction from normative data. Neither CD4 count, number of months since diagnosis of AIDS, number of AIDS-related illnesses, number of recent stressors, history of head injury/LOC, history of substance use, current or past psychiatric disorder, history of learning disability nor history of other medical illness were found to be significantly related to severity of cognitive impairment in this sample, after controlling for the effects of age, level of education, estimated premorbid IQ and mood status. However, no reliable conclusions could be drawn from this study because the small sample size resulted in an unacceptably low level of statistical power for the desired regression analysis. Exploratory analyses of variance revealed no significant group differences for any of the covariate or cofactor variables when subjects falling at the low, middle, and high ranges of severity of impairment were compared, with the exception of a possible inverse relationship with CD4 count. This was consistent with an exploratory stepwise regression analysis in which only CD4 count entered the model. Some potential limitations of the operational definitions used for the variables in this study were identified, and modifications were suggested. The results of additional exploratory analyses comparing group differences between the "globally impaired" and "unimpaired" subjects (Maj et al., 1994 criteria) on both the covariate and cofactor variables, and neuropsychological test performance, were also discussed.

<p>A fundamental characteristic of human visual perception is the ability to group together disparate elements in a scene and treat them as a single unit. The mechanisms by which humans create such groupings remain unknown, but grouping seems to play an important role in a wide variety of visual phenomena. I propose a neural model of grouping; through top-down control of its circuits, the model implements a grouping strategy that involves both a connection strategy (which elements to connect) and a selection strategy (spatiotemporal properties of a selection signal that segments target elements to facilitate identification). With computer simulations I explain how the circuits work and show how they can account for a wide variety of Gestalt principles of perceptual grouping. Additionally, I extend the model so that it can simulate visual search tasks. I show that when the model uses particular grouping strategies, simulated results closely match empirical results from replication experiments of three visual search tasks. In these experiments, perceptual grouping was induced by proximity and shape similarity (Palmer & Beck, 2007), by the spacing of irrelevant distractors and size similarity (Vickery, 2008), or by the proximity of dots and the proximity and shape similarity of line figures (Trick & Enns, 1997). Thus, I show that the model accounts for a variety of grouping effects and indicates which grouping strategies were likely used to promote performance in three visual search tasks. </p>

In the United States, an annual estimate of 1.36 million traumatic brain injuries present to the emergency department (ED), of which approximately 75% are concussions. Proper and timely treatment of concussion is especially important in pediatrics as children and adolescents under the age of 19 are at a higher risk for sustaining more severe and longer-lasting consequences. However, due to the wide range of symptoms at presentation, or to the potential lack of obvious symptoms, concussion can be especially difficult to diagnose in the ED setting. Neurocognitive tests provide a valuable supplement to the clinical diagnosis of concussion by objectively identifying aberrant brain activity. However, many of these tests are often too lengthy and impractical for use in the ED setting. The Immediate Post-Concussion Assessment and Cognitive Test (ImPACT) is a 20-minute computer test that is considered to be one of the gold-standard neurocognitive tests used to diagnose concussion and track recovery. The King-Devick test (KD) is a 1-2 minute test that uses saccadic eye movements to detect suboptimal brain impairment associated with concussion. To date, there have not been any studies that analyzed the relative usability of the KD and the ImPACT in the pediatric ED (PED). The present prospective pilot study investigates the use of the KD as a neurocognitive tool for concussion assessment in the PED and at a post-ED visit, relative to the ImPACT, the gold standard tool for concussion diagnosis. We hypothesize that the change in performance in the KD will correlate with the change in the ImPACT results. To date, 20 subjects between the ages of 11-18 years old presenting to the PED within 72 hours of sustaining a head injury have completed the study. The mean age of our study population was 13.6 years. The average change in test scores between PED and follow-up were: 7.2 seconds in the KD, 0.03 points in the ImPACT reaction time, 1.8 points in verbal memory, 8.3 points in visual memory, 0.8 points in visual motor speed, and 14.9 points in post-concussion symptom scale. Analysis of the correlation of the change in the KD scores to the change in the ImPACT measures revealed that the change in the KD was significantly correlated with the change in the ImPACT reaction time (p < 0.01), and with the change in the ImPACT verbal memory (p < 0.05) in the subjects that presented with LOC, 80% of whom were male. In conclusion, our findings report that the correlation between the results of the KD and the ImPACT is more pronounced in patients presenting with more severe head trauma, such as those leading to LOC. The usability of the KD as a reliable concussion assessment tool in the PED would require further investigation with a larger sample of participants. / 2017-04-30T00:00:00Z

Kognitiva sjukdomar är ett samlingsnamn för olika sjukdomar som framför allt påverkar en persons kognitiva funktioner men även till exempel kroppen och personens beteenden. Omkring 55 miljoner personer i världen beräknas ha en kognitiv sjukdom och i Sverige är siffran mellan 130 000–150 000. En stor andel av dessa bor hemma och ofta finns anhöriga som tar ett stort ansvar kring vården. Att vara anhörigvårdare kan upplevas som givande men det är ofta sammankopplat med en hög nivå av stress. Syftet med den här studien är att beskriva anhörigas upplevelser av att vårda en person med kognitiv sjukdom. Metoden för att svara på syftet är en allmän litteraturstudie, där data från 15 vetenskapliga artiklar analyserats och sammanställts. Resultatet delas in i två teman med tillhörande subteman: ”En omkullkastad tillvaro” och ”Att behöva anpassa sig till livsförändringen”. Slutsatsen blir att situationen som den anhörige hamnar i när en närstående får en kognitiv sjukdom ofta är mycket påfrestande. Det påverkar de flesta delar av livet, så som exempelvis vardagen, den egna hälsan, relationer och så vidare. Det finns ofta ett behov av stöd, både från människor i ens närhet och insatser från samhället. Den anhöriga behöver hitta strategier för att hantera den nya livssituationen för att motverka sådant som en låg upplevd livskvalitet och psykisk ohälsa. / Neurocognitive disorders are a group of different disorders that mainly affect a person ́s cognitive functions, but also domains as the physical body and the person ́s behavior. An estimated number of 55 million persons globally are diagnosed with some kind of neurocognitive disorder and the number in Sweden is among 130 000–150 000. The majority of the persons with a neurocognitive disorder live at home and in many cases they have a family member or friend who is responsible for the caregiving, an informal caregiver. The role of the informal caregiver can be rewarding, but it often comes with a high level of strain. The aim of this study is to describe the informal caregiver ́s experience of taking care of a person with neurocognitive disorder. The method that is used is a general literature review that contains data from 15 scientific papers. The data has been analyzed and compiled. The result was categorized in two themes and sub-themes: ”When life is turned upside down” and ”Having to adapt to the life change”. The conclusion is that the situation of being an informal caregiver is very stressful. It affects almost all aspects of one ́s life, including the everyday life, one ́s own health and relationships. The informal caregiver is in need of support from family and friends as well as formal support. The informal caregiver must find constructive coping strategies to deal with the new situation to avoid mental illness or low level of perceived quality of life.

Acute aerobic exercise exerts a small beneficial effect on cognition. Much of the research to date has focused on cognitive changes following a bout of exercise, while little is currently known about changes in cognitive performance during exercise. The limited research that has been conducted suggests either positive, negative, or no effects on cognitive performance during exercise. Thus, the primary purpose of this study was to examine the effects of low-intensity cycling on cognitive function in college-aged students, indexed by response accuracy, reaction time, P3 amplitude, and P3 latency. Twenty-seven (Mage = 22.9 ± 3.0 years old) college-aged individuals were counterbalanced into low-intensity exercise (EX) and seated control (SC) conditions. During each condition, participants completed a 10-minute resting baseline period, 20 minutes of either sustained cycling or seated rest, and a 20-minute recovery period. Primary outcomes were assessed at 10-minute intervals (5 blocks total) throughout each condition via a modified oddball task. Across time blocks, both conditions exhibited faster reaction times on frequent trials but reduced accuracy to rare trials, suggesting a speed-accuracy tradeoff. There were no differences between conditions in P3 latency whereas a significant reduction in P3 amplitude was observed during the 20-minute exercise period compared to the control condition. Taken together, the results suggest that exercise at lower doses may have minimal influence on behavioral outcomes of cognitive performance but may impact more basic measures of brain function. Information gathered from this study may aid in the development of appropriate exercise prescriptions for populations looking to specifically target cognitive function deficits.

Memory deficits in Alzheimer’s disease (AD) and mild cognitive impairment (MCI) can be reflected in language-based tests, especially spontaneous speech tasks. Three spontaneous speech tests were developed in this study, including Thai Picture description (TPD), Thai Story Recall (TSR), and Semi-structured Interview for Thai (SIT) Ninety-eight Thai older adults underwent screening tests and three spontaneous speech tests. Then they were classified into three groups, including healthy control (HC), MCI, and AD. Their verbal responses were extracted into the content variables and acoustic features. Then the discriminant ability and accuracy in differentiating HC, MCI, and AD were examined with by Multivariate Discriminant Analysis (MDA) and analysis of the ROC curve and AUC. Two content variables showed significant differences among three groups of participants, i.e., correct information unit (CIU) of the TPD and delayed recall scores of the TSR. For acoustic features, ANOVAs revealed that three variables were significantly different among the three experimental groups, i.e., total utterance time in delayed recall, number of voice breaks in the TPD, and the SIT. The result of a stepwise estimation in MDA presented that the best combination of predictive model was CIU and backward digit span (BDS), in which provides 61.1% of correct classification. This discriminant function showed AUC of .81 in differentiating HC and MCI, AUC of .91 in distinguishing HC and AD, and AUC of .86 in detecting persons with cognitive impairments (MCI and AD) from HC. In conclusion, the combination of CIU of TPD and BDS is suitable for differentiating AD and persons with cognitive impairments from HC. However, there is no appropriate predictor in distinguishing MCI and AD.

No description available.

Heterogeneity in the profile of HIV-associated neuropsychological disorder (HAND) may obscure understanding of its etiology and prognosis. Despite longstanding acknowledgement of this heterogeneity, HAND diagnostic approaches such as the Frascati criteria characterize neuropsychological function based on the level of impairment, without regard to the pattern of strengths and weaknesses. Attention to these patterns may enhance etiologic and prognostic specificity. We used latent class analysis (LCA) to identify relatively homogeneous subtypes of neurocognitive function in adults with well-treated HIV infection. We compared the diagnostic agreement of latent classes and Frascati categories, as well as their associations with demographics, HIV markers and antiretroviral factors, comorbid medical and psychiatric conditions, and everyday functioning. LCA identified four classes, whose cognitive profiles are depicted in Figure 1: cognitively intact, mild-to-moderate motor/speed impairment, mild-to-moderate memory/visuoconstruction impairment, and moderate mixed impairment. Latent classes and Frascati categories demonstrated good agreement in the overall classification of impaired cognition but more disagreement regarding subtypes of impairment. Both latent classes and Frascati categories demonstrated unique associations with etiologic factors and significant associations with functional outcomes. However, only latent classes, not Frascati categories, were associated with HIV variables. Additionally, functional difficulties were significantly elevated in the motor impairment class but not the memory impairment class despite similar levels of cognitive impairment in the two groups. Findings support the utility of a diagnostic approach that accounts for both the level and pattern of neurocognitive impairment. Future research should examine the neuropathological mechanisms, longitudinal trajectories, and treatments of empirically identified HAND subtypes. / Psychology

INTRODUCTION: HIV- associated neurocognitive disorder (HAND) and pathology are common manifestations of HIV-infection, and often persist in spite of controlled peripheral viremia. Severity of HAND can range from loss of concentration and psychological changes to frank dementia. Inflammatory host-immune responses and chemotaxis of immune cells into the CNS are thought to be integral to development of NeuroAIDS and HAND. OBJECTIVES: This studies' primary aim was to determine if significant differences existed between Substance P and NK1R expression in brain tissue samples of HIV-infected individuals with neurocognitive disorder or pathology. The secondary aim was to determine whether expression of HIV viral entry receptors CCR5 and CXCR4 correlate with expression of Substance P or NK1R. The tertiary aim of this study was to determine if age at death, CNS penetration-effectiveness of antiretroviral therapy, diagnosis before HAART, average plasma CD4, or abnormal alcohol or drug use increased prevalence of neurocognitive disease. STUDY DESIGN: Cross-sectional study of HIV-infected individuals (n=60) from the larger National NeuroAIDS Tissue Consortium Cohort. Pre-death demographic data, neurocognitive assessment, alcohol and drug use, ART regimens, date of diagnosis and death, and plasma CD4 levels, as well as pathology findings at autopsy and brain tissue samples were provided by the NNTC; expression levels of Substance P, NK1R, CCR5, and CXCR4 from brain samples were provided by Dr. Steven Douglas of The Children's Hospital of Philadelphia. RESULTS: In this sample of HIV-infected individuals, Substance P expression was significantly less in the cingulate cortex of individuals with (p=0.003). Within-subject expression patterns of CCR5 and truncated-NK1R in the cingulate cortex and cerebellum were both significantly altered by neuropathology and cannabis use; CCR5 expression was also significantly affected by opiate use. CCR5 and CXCR4 expression correlated strongly with truncated-NK1R expression. No between-subject factors significantly altered prevalence of neurocognitive impairment in this HIV-infected population. CONCLUSIONS: The study found significant changes in Substance P, NK1R, and CCR5 expression associated with neuropathology. Furthermore, in heterogeneous populations, expression patterns may be more important than overall level of expression in identifying risk factors for NeuroAIDS and other chronic diseases. / Epidemiology