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Research Square Jan 2024Urine albumin, high in kidney disease, predicts cardiovascular incidents and CNS white matter hyperintensity (WMH) burdens. Serum albumin - a more general biomarker...
Urine albumin, high in kidney disease, predicts cardiovascular incidents and CNS white matter hyperintensity (WMH) burdens. Serum albumin - a more general biomarker which can be low in several disorders - including kidney and liver disease, malnutrition, and inflammation - also predicts cardiovascular events and is associated with cognitive impairment in several clinical populations; relations between serum albumin and WMH prevalence, however, have rarely been evaluated. In a sample of 160 individuals with alcohol use disorder (AUD), 142 infected with HIV, and 102 healthy controls, the hypothesis was tested that lower serum albumin levels would predict larger WMH volumes and worse cognitive performance irrespective of diagnosis. After considering traditional cardiovascular risk factors (e.g., age, sex, body mass index (BMI), nicotine use, hypertension, diabetes) and study-relevant variables (i.e., primary diagnoses, race, socioeconomic status, hepatitis C virus status), serum albumin survived false discovery rate (FDR)-correction in contributing variance to larger periventricular but not deep WMH volumes. This relationship was salient in the AUD and HIV groups, but not the control group. In secondary analyses, serum albumin and periventricular WMH along with age, sex, diagnoses, BMI, and hypertension were considered for hierarchical contribution to variance in performance in 4 cognitive domains. Albumin survived FDR-correction for significantly contributing to visual and verbal learning and memory performance after accounting for diagnosis. Relations between albumin and markers of liver integrity [e.g., aspartate transaminase (AST)] and blood status (e.g., hemoglobin, red blood cell count, red cell distribution width) suggest that in this sample, albumin reflects both liver dysfunction and hematological abnormalities. The current results suggest that albumin, a simple serum biomarker available in most clinical settings, can predict variance in periventricular WMH volumes and performance in visual and verbal learning and memory cognitive domains. Whether serum albumin contributes mechanistically to periventricular WMH prevalence will require additional investigation.
PubMed: 38260299
DOI: 10.21203/rs.3.rs-3822513/v1 -
PloS One 2024Prior cross-cultural studies have demonstrated differences among Eastern and Western cultures in memory and cognition along with variation in neuroanatomy and functional...
Prior cross-cultural studies have demonstrated differences among Eastern and Western cultures in memory and cognition along with variation in neuroanatomy and functional engagement. We further probed cultural neuroanatomical variability in terms of its relationship with memory performance. Specifically, we investigated how memory performance related to gray matter volume in several prefrontal lobe structures, including across cultures. For 58 American and 57 Taiwanese young adults, memory performance was measured with the California Verbal Learning Test (CVLT) using performance on learning trial 1, on which Americans had higher scores than the Taiwanese, and the long delayed free recall task, on which groups performed similarly. MRI data were reconstructed using FreeSurfer. Across both cultures, we observed that larger volumes of the bilateral rostral anterior cingulate were associated with lower scores on both CVLT tasks. In terms of effects of culture, the relationship between learning trial 1 scores and gray matter volumes in the right superior frontal gyrus had a trend for a positive relationship in Taiwanese but not in Americans. In addition to the a priori analysis of select frontal volumes, an exploratory whole-brain analysis compared volumes-without considering CVLT performance-across the two cultural groups in order to assess convergence with prior research. Several cultural differences were found, such that Americans had larger volumes in the bilateral superior frontal and lateral occipital cortex, whereas Taiwanese had larger volumes in the bilateral rostral middle frontal and inferior temporal cortex, and the right precuneus.
Topics: Humans; Young Adult; Brain; Cognition; Gray Matter; Magnetic Resonance Imaging; Prefrontal Cortex; Temporal Lobe; Taiwan; North American People; United States
PubMed: 38551909
DOI: 10.1371/journal.pone.0298235 -
CNS Spectrums Jun 2024Trichotillomania (TTM) is a mental health disorder characterized by repetitive urges to pull out one's hair. Cognitive deficits have been reported in people with TTM... (Meta-Analysis)
Meta-Analysis
OBJECTIVE
Trichotillomania (TTM) is a mental health disorder characterized by repetitive urges to pull out one's hair. Cognitive deficits have been reported in people with TTM compared to controls; however, the current literature is sparse and inconclusive about affected domains. We aimed to synthesize research on cognitive functioning in TTM and investigate which cognitive domains are impaired.
METHODS
After preregistration on the International Prospective Register of Systematic Reviews (PROSPERO), we conducted a comprehensive literature search for papers examining cognition in people with TTM versus controls using validated tests. A total of 793 papers were screened using preestablished inclusion/exclusion criteria, yielding 15 eligible studies. Random-effects meta-analysis was conducted for 12 cognitive domains.
RESULTS
Meta-analysis demonstrated significant deficits in motor inhibition and extradimensional (ED) shifting in people with TTM versus controls as measured by the stop-signal task (SST) (Hedge's = 0.45, [CI: 0.14, 0.75], = .004) and ED set-shift task ( = 0.38, [CI: 0.13, 0.62], = .003), respectively. There were no significant between-group differences in the other cognitive domains tested: verbal learning, intradimensional (ID) shifting, road map spatial ability, pattern recognition, nonverbal memory, executive planning, spatial span length, Stroop inhibition, Wisconsin card sorting, and visuospatial functioning. Findings were not significantly moderated by study quality scores.
CONCLUSIONS
Motor inhibition and ED set-shifting appear impaired in TTM. However, a cautious interpretation of results is necessary as samples were relatively small and frequently included comorbidities. Treatment interventions seeking to improve inhibitory control and cognitive flexibility merit exploration for TTM.
Topics: Humans; Cognition; Neuropsychological Tests; Trichotillomania
PubMed: 38477170
DOI: 10.1017/S1092852924000129 -
Translational Psychiatry Oct 2023Cognitive impairment is a core feature of schizophrenia, which is aggravated by antipsychotics-induced metabolic disturbance and lacks effective pharmacologic treatments... (Randomized Controlled Trial)
Randomized Controlled Trial
Cognitive impairment is a core feature of schizophrenia, which is aggravated by antipsychotics-induced metabolic disturbance and lacks effective pharmacologic treatments in clinical practice. Our previous study demonstrated the efficiency of metformin in alleviating metabolic disturbance following antipsychotic administration. Here we report that metformin could ameliorate cognitive impairment and improve functional connectivity (FC) in prefrontal regions. This is an open-labeled, evaluator-blinded study. Clinically stable patients with schizophrenia were randomly assigned to receive antipsychotics plus metformin (N = 48) or antipsychotics alone (N = 24) for 24 weeks. The improvement in cognition was assessed by the MATRICS Consensus Cognitive Battery (MCCB). Its association with metabolic measurements, and voxel-wise whole-brain FC with dorsolateral prefrontal cortex (DLPFC) subregions as seeds were evaluated. When compared to the antipsychotics alone group, the addition of metformin resulted in significantly greater improvements in the MCCB composite score, speed of processing, working memory, verbal learning, and visual learning. A significant time × group interaction effect of increased FC between DLPFC and the anterior cingulate cortex (ACC)/middle cingulate cortex (MCC), and between DLPFC subregions were observed after metformin treatment, which was positively correlated with MCCB cognitive performance. Furthermore, the FC between left DLPFC A9/46d to right ACC/MCC significantly mediated metformin-induced speed of processing improvement; the FC between left A46 to right ACC significantly mediated metformin-induced verbal learning improvement. Collectively, these findings demonstrate that metformin can improve cognitive impairments in schizophrenia patients and is partly related to the FC changes in the DLPFC. Trial Registration: The trial was registered with ClinicalTrials.gov (NCT03271866). The full trial protocol is provided in Supplementary Material.
Topics: Humans; Schizophrenia; Dorsolateral Prefrontal Cortex; Magnetic Resonance Imaging; Cognitive Dysfunction; Cognition; Antipsychotic Agents; Prefrontal Cortex
PubMed: 37821461
DOI: 10.1038/s41398-023-02616-x -
Neuropsychology Jan 2024Much of our knowledge concerning the neural basis of human memory derives from lab-based verbal recall tasks. Outside of the lab, clinicians use validated and normed...
OBJECTIVE
Much of our knowledge concerning the neural basis of human memory derives from lab-based verbal recall tasks. Outside of the lab, clinicians use validated and normed neuropsychological tests to assess patients' memory function and to evaluate clinical interventions. Here we sought to establish the clinical validity of examining memory through multitrial free recall of semantically organized and unrelated word lists.
METHOD
We compare memory performance in multitrial free recall tasks with the Rey Auditory Verbal Learning Test and the California Verbal Learning Test, two common neuropsychological tests aimed at evaluating memory function in clinical settings. We compare predictive validity between the tasks by evaluating deficits in a patient sample and examining age-related declines in memory. We additionally compare test-retest reliability, establish convergent validity, and show the emergence of common recall dynamics between the tasks.
RESULTS
We demonstrate that both laboratory free recall tasks have better predictive validity and test-retest reliability than the established neuropsychological tests. We further show that all tasks have good convergent validity and reveal core memory processes, including temporal and semantic organization. However, we also demonstrate the benefits of repeated trials for evaluating the dynamics of memory search and their neuropsychological sequelae.
CONCLUSIONS
These results provide evidence for the clinical validity of lab-based multitrial free recall tasks and highlight their psychometric benefits over neuropsychological measures. Based on these results, we discuss the need to bridge the gap between clinical understanding of putative mechanisms underlying memory disorders and neuroscientific findings obtained using lab-based free recall tasks. (PsycInfo Database Record (c) 2023 APA, all rights reserved).
Topics: Humans; Reproducibility of Results; Verbal Learning; Mental Recall; Memory; Neuropsychological Tests
PubMed: 37870806
DOI: 10.1037/neu0000910 -
Neuropsychological Rehabilitation Aug 2023Persons with amnestic Mild Cognitive Impairment (aMCI) are at risk for experiencing changes in their daily functioning due to their memory impairment. The Memory Support...
Procedural learning, declarative learning, and working memory as predictors of learning the use of a memory compensation tool in persons with amnestic mild cognitive impairment.
Persons with amnestic Mild Cognitive Impairment (aMCI) are at risk for experiencing changes in their daily functioning due to their memory impairment. The Memory Support System (MSS), a compensatory calendaring system, was developed to support functional independence in persons with aMCI (pwaMCI). This cross-sectional study examined procedural learning, declarative learning, and working memory as predictors of MSS learning efficiency in pwaMCI. Sixty pwaMCI participated in MSS training. The Serial Reaction Time Test and Mirror Tracing Test were used to assess procedural learning. The Rey Auditory Verbal Learning Test and CogState One Card Learning were used to assess declarative learning and the CogState One Back task was used to assess working memory. Multiple regression analyses were conducted to assess if procedural learning, declarative learning, and working memory predicted MSS learning efficiency. This study showed that declarative learning predicted MSS learning efficiency in pwaMCI, with less consistent results for procedural learning and non-significant results for working memory. Findings suggest that success in teaching compensatory tools is greater when training is offered in early aMCI before declarative learning skill is fully lost. Future studies should assess additional strategies to facilitate MSS learning in advanced aMCI.
Topics: Humans; Memory, Short-Term; Cross-Sectional Studies; Learning; Cognitive Dysfunction; Memory Disorders; Neuropsychological Tests
PubMed: 35749375
DOI: 10.1080/09602011.2022.2089697 -
Neuropsychology Jul 2023(a) To characterize the frequency of objective cognitive deficits and self-perceived cognitive difficulties and (b) to explore demographic and clinical predictors of...
OBJECTIVES
(a) To characterize the frequency of objective cognitive deficits and self-perceived cognitive difficulties and (b) to explore demographic and clinical predictors of cognitive dysfunction and cognitive complaints.
METHOD
One hundred and ten adults diagnosed with COVID-19 between March and November 2020, aged ≤ 74 years underwent a brief neuropsychological evaluation 12 months after infection, which included: Brief Visuospatial Memory Test-Revised, California Verbal Learning Test, and Symbol Digit Modalities Test. T scores < 38 were considered abnormal performance; cognitive dysfunction was defined as ≥ 2 abnormal tests. Participants also completed Broadbent's Cognitive Failure Questionnaires (CFQ), Hospital Anxiety and Depression Scale, Modified Fatigue Impact Scale, and Short-Form Health Survey. CFQ ≥ 43 was considered indicative of cognitive complaints.
RESULTS
Twenty participants (18.2%) had cognitive dysfunction and 36 (33.3%) had cognitive complaints. Cognitive dysfunction was related to lower education, preinfection history of headache/migraine, and acute COVID-19 symptoms of headache and sleep disturbance. Cognitive complaints were more likely to occur in women, those with fewer years of education, and acute COVID-19 symptoms of headache and sleep disturbance. Cognitive complaints were also significantly related to symptoms of anxiety, depression, and fatigue. Sex and psychopathology were not significant predictors of cognitive dysfunction. Modest associations were found between CFQ total score and cognitive test performance.
DISCUSSION
A subset of individuals develops cognitive difficulties in the context of post-COVID syndrome. Results may support the protective effect of education, a known proxy of cognitive reserve. COVID-19 infection symptoms of headache and sleep disturbance appear to be risk factors for long-term cognitive difficulties. (PsycInfo Database Record (c) 2023 APA, all rights reserved).
Topics: Adult; Humans; Female; COVID-19; Cognitive Dysfunction; Cognition Disorders; Fatigue; Neuropsychological Tests; Headache
PubMed: 36603126
DOI: 10.1037/neu0000876 -
The Journal of Neuroscience : the... Jul 2023Fear learning allows us to identify and anticipate aversive events and adapt our behavior accordingly. This is often thought to rely on associative learning mechanisms...
Fear learning allows us to identify and anticipate aversive events and adapt our behavior accordingly. This is often thought to rely on associative learning mechanisms where an initially neutral conditioned stimulus (CS) is repeatedly paired with an aversive unconditioned stimulus (US), eventually leading to the CS also being perceived as aversive and threatening. Importantly, however, humans also show verbal fear learning. Namely, they have the ability to change their responses to stimuli rapidly through verbal instructions about CS-US pairings. Past research on the link between experience-based and verbal fear learning indicated that verbal instructions about a reversal of CS-US pairings can fully override the effects of previously experienced CS-US pairings, as measured through fear ratings, skin conductance, and fear-potentiated startle. However, it remains an open question whether such instructions can also annul learned CS representations in the brain. Here, we used a fear reversal paradigm (female and male participants) in conjunction with representational similarity analysis of fMRI data to test whether verbal instructions fully override the effects of experienced CS-US pairings in fear-related brain regions or not. Previous research suggests that only the right amygdala should show lingering representations of previously experienced threat ("pavlovian trace"). Unexpectedly, we found evidence for the residual effect of prior CS-US experience to be much more widespread than anticipated, in the amygdala but also cortical regions like the dorsal anterior cingulate or dorsolateral prefrontal cortex. This finding shines a new light on the interaction of different fear learning mechanisms, at times with unexpected consequences. Humans are able to learn about aversive stimuli both from experience (i.e., repeated pairings of conditioned stimulus (CS) and unconditioned stimulus (US; pavlovian conditioning), and from verbal instructions about stimulus pairings. Understanding how experience-based and verbal learning processes interact is key for understanding the cognitive and neural underpinnings of fear learning. We tested whether prior aversive experiences (CS-US pairings) affected subsequent verbal learning, searching for lingering threat signals after verbal instructions reversed a CS from being threatening to being safe. While past research suggested such threat signals can only be found in the amygdala, we found evidence to be much more widespread, including the medial and lateral PFC. This highlights how experience-based and verbal learning processes interact to support adaptive behavior.
Topics: Humans; Male; Female; Conditioning, Classical; Fear; Conditioning, Operant; Brain; Learning
PubMed: 37414559
DOI: 10.1523/JNEUROSCI.0665-22.2023 -
Neuropsychologia May 2024Semantic Dementia (SD) is a neurodegenerative disease characterised by progressive deterioration of semantic knowledge, resulting in diminished understanding of... (Review)
Review
Semantic Dementia (SD) is a neurodegenerative disease characterised by progressive deterioration of semantic knowledge, resulting in diminished understanding of concepts, whether encountered in verbal or non-verbal form. Over the past three decades, a number of studies employing a range of treatment techniques and learning methods have examined whether patients with SD can relearn previously known concepts or learn and retain new information. In this article, we review this research, addressing two main questions: a) Can aspects of semantic knowledge that are 'lost' due to degeneration be re-acquired? b) How much do other memory systems (working and episodic memory) interact with and depend on semantic memory? Several studies demonstrate successful relearning of previously known words and concepts in SD, particularly after regular, prolonged practice; but this success tends to diminish once practice ceases, and furthermore often fails to generalise to other instances of the same object/concept. This pattern suggests that, with impaired semantic knowledge, learning relies to an abnormal extent on perceptual factors, making it difficult to abstract away from the specific visual or other perceptual format in which a given concept has been trained. Furthermore, the impact of semantic 'status' of a word or object on both working and episodic memory indicates pervasive interaction of these other memory systems with conceptual knowledge.
Topics: Humans; Frontotemporal Dementia; Neurodegenerative Diseases; Learning; Memory; Mental Recall; Semantics; Neuropsychological Tests
PubMed: 38428519
DOI: 10.1016/j.neuropsychologia.2024.108844 -
Psychological Medicine Oct 2023Studies investigating cognitive impairments in psychosis and depression have typically compared the average performance of the clinical group against healthy controls...
BACKGROUND
Studies investigating cognitive impairments in psychosis and depression have typically compared the average performance of the clinical group against healthy controls (HC), and do not report on the actual of cognitive impairments or strengths within these clinical groups. This information is essential so that clinical services can provide adequate resources to supporting cognitive functioning. Thus, we investigated this prevalence in individuals in the early course of psychosis or depression.
METHODS
A comprehensive cognitive test battery comprising 12 tests was completed by 1286 individuals aged 15-41 (mean age 25.07, s.d. 5.88) from the PRONIA study at baseline: HC ( = 454), clinical high risk for psychosis (CHR; = 270), recent-onset depression (ROD; = 267), and recent-onset psychosis (ROP; = 295). Z-scores were calculated to estimate the prevalence of moderate or severe deficits or strengths (>2 s.d. or 1-2 s.d. below or above HC, respectively) for each cognitive test.
RESULTS
Impairment in at least two cognitive tests was as follows: ROP (88.3% moderately, 45.1% severely impaired), CHR (71.2% moderately, 22.4% severely impaired), ROD (61.6% moderately, 16.2% severely impaired). Across clinical groups, impairments were most prevalent in tests of working memory, processing speed, and verbal learning. Above average performance (>1 s.d.) in at least two tests was present for 40.5% ROD, 36.1% CHR, 16.1% ROP, and was >2 SDs in 1.8% ROD, 1.4% CHR, and 0% ROP.
CONCLUSIONS
These findings suggest that interventions should be tailored to the individual, with working memory, processing speed, and verbal learning likely to be important transdiagnostic targets.
Topics: Humans; Adult; Depression; Prevalence; Psychotic Disorders; Cognitive Dysfunction; Cognition Disorders; Neuropsychological Tests
PubMed: 37409883
DOI: 10.1017/S0033291723001770