Slower Processing Speed Research Articles

Clinical Neuropsychological Evaluation in Older Adults With Major Depressive Disorder.

Older adults with major depressive disorder are particularly vulnerable to MDD-associated adverse cognitive effects including slowed processing speed, decreased attention, and executive dysfunction. The purpose of this review is to describe the approach to a clinical neuropsychological evaluation in older adults with MDD. Specifically, this review compares and contrasts neurocognitive screening and clinical neuropsychological evaluation procedures and details the multiple components of the clinical neuropsychological evaluation. Research has shown that neurocognitive screening serves a useful purpose to provide an acute and rapid assessment of global cognitive function; however, it has limited sensitivity and specificity. The clinical neuropsychological evaluation process is multifaceted and encompasses a review of available medical records, neurobehavioral status and diagnostic interview, comprehensive cognitive and clinical assessment, examination of inclusion and diversity factors as well as symptom and performance validity, and therapeutic feedback. As such, the evaluation provides invaluable information on multiple cognitive functions, establishes brain and behavior relationships, clarifies neuropsychiatric diagnoses, and can inform the etiology of cognitive impairment. Clinical neuropsychological evaluation plays a unique and critical role in integrated healthcare for older adults with MDD. Indeed, the evaluation can serve as a nexus to synthesize information across healthcare providers in order to maximize measurement-based care that can optimize personalized medicine and overall health outcomes.

Evidence of High-Detail Perceptual Modeling in the Visual Cortex

This informal but well-referenced description of an afterimage experiment called Ghost Tap provides persuasive and easily reproducible evidence that the visual cortex plays a significant role in certain classes of long-duration visual afterimages. Subjects of the experiment literally cannot discern the difference between the afterimage and reality, resulting in easy startling of the subjects when physical motion in the room no longer matches the persuasive afterimages they are perceiving. Anecdotal examples of less extreme versions of the same effect suggest that the Ghost Tap effect has, over centuries, intentionally and unintentionally helped persuade people of the existence of nominally “supernatural” effects that are just persuasive long-duration afterimages. While this description is informal, the easy reproducibility of the Ghost Tap makes it a good candidate for more precise and quantitative studies. One theory why Ghost Tap exists is that it is part of load reduction and speed enhancement strategy to compensate for the slow processing speeds of neurons. Maintaining a dynamic and predictive real-time model of likely sensory inputs from the external world would enable the brain to discard quickly and with minimal processing any sensory inputs that fall within the predictive tolerance limits to the current model state. A perceptive load reduction interpretation of the Ghost Tap argues that the ability of the brain to support dreaming in vivid detail is likely a direct corollary of its ability to create dream-like waking states for faster and more efficient processing of large sensory loads. If the brain regularly uses dream-like waking states to reduce data, more study of effects like Ghost Tap might help explain the frequency of pathologies in which perception becomes disconnected from reality.

Assessment of Neuropsychological Function in Veterans With Blast-Related Mild Traumatic Brain Injury and Subconcussive Blast Exposure.

Objective: The majority of combat-related head injuries are associated with blast exposure. While Veterans with mild traumatic brain injury (mTBI) report cognitive complaints and exhibit poorer neuropsychological performance, there is little evidence examining the effects of subconcussive blast exposure, which does not meet clinical symptom criteria for mTBI during the acute period following exposure. We compared chronic effects of combat-related blast mTBI and combat-related subconcussive blast exposure on neuropsychological performance in Veterans.Methods: Post-9/11 Veterans with combat-related subconcussive blast exposure (n = 33), combat-related blast mTBI (n = 26), and controls (n = 33) without combat-related blast exposure, completed neuropsychological assessments of intellectual and executive functioning, processing speed, and working memory via NIH toolbox, assessment of clinical psychopathology, a retrospective account of blast exposures and non-blast-related head injuries, and self-reported current medication. Huber Robust Regressions were employed to compare neuropsychological performance across groups.Results: Veterans with combat-related blast mTBI and subconcussive blast exposure displayed significantly slower processing speed compared with controls. After adjusting for post-traumatic stress disorder and depressive symptoms, those with combat-related mTBI exhibited slower processing speed than controls.Conclusion: Veterans in the combat-related blast mTBI group exhibited slower processing speed relative to controls even when controlling for PTSD and depression. Cognition did not significantly differ between subconcussive and control groups or subconcussive and combat-related blast mTBI groups. Results suggest neurocognitive assessment may not be sensitive enough to detect long-term effects of subconcussive blast exposure, or that psychiatric symptoms may better account for cognitive sequelae following combat-related subconcussive blast exposure or combat-related blast mTBI.

Within-day rhythms of pain and cognitive function in people with and without fibromyalgia: synchronous or syncopated?

Cognitive dysfunction is a common fibromyalgia (FM) symptom and can impact on the daily lives of those affected. We investigated whether within-day pain intensity ratings were associated with contemporaneous objective and subjective measures of cognitive function and whether within-day increases in pain intensity preceded increases in cognitive dysfunction or vice versa. Inclusion of a non-FM group allowed us to examine whether effects were specific to FM. Fifty people with FM and 50 non-FM controls provided 7 days of data. Cognitive tests (processing speed and working memory) and ecological momentary assessments (pain intensity and self-reported cognitive functioning) were conducted ×5/day. Three-level multilevel models examined contemporaneous and within-day 1-lag pain intensity-cognitive functioning associations. Interaction terms assessed possible moderating effects of FM status. Momentary increase in pain was associated with increased self-reported cognitive dysfunction, more strongly so for those with FM (B = 0.27, 95% confidence interval 0.22-0.32; non-FM B = 0.17, 95% confidence interval 0.10-0.23). For the FM group, higher pain was associated with longer processing speed; for the non-FM group, higher pain was associated with shorter processing speed. Pain increase did not precede change in subjective or objective cognitive function in the FM group, but reduction in working memory preceded increase in pain intensity. This finding warrants further research attention and, if replicated, could hold prognostic and/or therapeutic potential.

A quick test of cognitive speed (AQT): regression-based norms for cognitively healthy 80 to 94-year olds

ABSTRACT Slowed processing speed is part of normal aging but also a symptom of many diseases, including dementia. A Quick Test of Cognitive Speed (AQT) consists of three conditions: color naming (AQT1), form naming (AQT2) and dual color-form naming (AQT3) and offers a user-friendly assessment of processing speed that is used internationally to identify cognitive impairment in elderly patients. Appropriate age-norms have however been lacking. This study provides regression-based norms derived from a Swedish sample of 158 cognitively healthy 80 to 94-year olds. The results show age effects in all three conditions, a non-linear education effect in AQT1, and age by gender interactions in AQT2 and AQT3: men performed worse with increasing age, but women remained on a par. However, irrespective of age and gender, AQT2 and AQT3 mean raw and predicted scores were slower than the hitherto recommended cutoff criteria for suspected cognitive impairment.

Cerebral small vessel disease burden and longitudinal cognitive decline from age 73 to 82: the Lothian Birth Cohort 1936

Slowed processing speed is considered a hallmark feature of cognitive decline in cerebral small vessel disease (SVD); however, it is unclear whether SVD’s association with slowed processing might be due to its association with overall declining general cognitive ability. We quantified the total MRI-visible SVD burden of 540 members of the Lothian Birth Cohort 1936 (age: 72.6 ± 0.7 years; 47% female). Using latent growth curve modelling, we tested associations between total SVD burden at mean age 73 and changes in general cognitive ability, processing speed, verbal memory and visuospatial ability, measured at age 73, 76, 79 and 82. Covariates included age, sex, vascular risk and childhood cognitive ability. In the fully adjusted models, greater SVD burden was associated with greater declines in general cognitive ability (standardised β: −0.201; 95% CI: [−0.36, −0.04]; pFDR = 0.022) and processing speed (−0.222; [−0.40, −0.04]; pFDR = 0.022). SVD burden accounted for between 4 and 5% of variance in declines of general cognitive ability and processing speed. After accounting for the covariance between tests of processing speed and general cognitive ability, only SVD’s association with greater decline in general cognitive ability remained significant, prior to FDR correction (−0.222; [−0.39, −0.06]; p = 0.008; pFDR = 0.085). Our findings do not support the notion that SVD has a specific association with declining processing speed, independent of decline in general cognitive ability (which captures the variance shared across domains of cognitive ability). The association between SVD burden and declining general cognitive ability supports the notion of SVD as a diffuse, whole-brain disease and suggests that trials monitoring SVD-related cognitive changes should consider domain-specific changes in the context of overall, general cognitive decline.

Improving the speed of ball detection process and obstacle detection process in ERSOW robot using omnidirectional vision based on ROS

This paper presents a novel approach for improving the computation speed of the ball detection and obstacle detection processes in our robot. The conditions of obstacle detection and ball detection in our robot still have a slow processing speed, this condition makes the robot not real-time and the robot's movement is hampered. To build a good world model, things to note are obstacle information and real-time ball detection. The focus of this research is to increase the speed of the process of the ball and obstacle detection around the robot. To increase the speed of the process, it is necessary to optimize the use of the OpenCV library on the robot operating system (ROS) system to divide the process into several small processes so that the work can be optimally divided into threads that have been created. Then, minimize the use of too many frames. This information will be sent to the base station and also for obstacle avoidance purposes.

Association of Drug Burden Index With Measures of Cognitive Function Among Older Adults

Abstract Objectives Many conditions associated with aging result in polypharmacy, and certain medications may impact cognition. One way to assess exposure to such medications is through the use of the drug burden index (DBI)- a validated measure of exposure to anticholinergic and sedative medications, with a higher DBI score indicating a higher drug burden. The objective of this cross-sectional analysis was to investigate the association between DBI and cognitive function assessed by two widely utilized cognitive tests among older adults. Methods The Health, Aging, and Body Composition Study was a prospective study of community-dwelling adults ages 70–79 years at enrollment. Using baseline data, DBI was calculated by dividing the daily dose of the medication taken by the sum of the daily dose taken and the minimum efficacious dose as approved by the Food and Drug Association. After adjusting for biological sex, race, education, and APOE genotype, the association between DBI and the Digit Symbol Substitution Test (DSST) and Modified Mini-Mental Status Exam (3MS) score was assessed by partial Spearman's rank correlation. Kruskal-Wallis tests were employed to assess significance among DBI scores by tertile. Results Among those with completed measures (n = 790, 52.4% male, 63.3% white), mean scores were as follows: DBI 0.84 ± 0.48, 3MS 90.12 ± 7.9, and DSST 34.7 ± 14.6. Results suggest that DBI was not significantly associated with either 3MS or DSST. However, DBI scores by tertile were significantly associated with DSST scores. Compared to tertile 2, participants in the lowest tertile had significantly lower DBI scores along with significantly higher DSST scores. Mean differences between tertile 1 and 2 were as follows: DBI = 0.1666 and DSST = 3.39. Conclusions Analyses among the full cohort suggest that DBI was not associated with slower processing speed as assessed by the DSST or with global cognition as assessed by 3MS. Yet with expanded analysis by tertile, results suggest that DBI scores were significantly associated with DSST scores. Future investigations on cognitive function among older adults may benefit from including the DBI analysis by tertile to explain some variance in cognitive test scores. Funding Sources This is an ancillary analysis, there is no funding applicable.

Abstract P202: Early To Midlife Smoking Trajectories And Cognitive Function In Middle Aged Us Adults: The Coronary Artery Risk Development In Young Adults Study

Introduction: Smoking starts in early adulthood and persists throughout the lifecourse, but the association between these trajectories and midlife cognition remains unclear. We assessed the hypothesis that individuals with a heavy smoking trajectory from early adulthood to midlife would be more likely to demonstrate poor cognition at midlife. Methods: We studied 3364 participants (mean age: 50.1±3.6, 56% female, 46% black) from the Coronary Artery Risk Development in Young Adults (CARDIA) study. Smoking trajectories were derived in latent class analysis among 1638 ever smokers based on smoking measures every 2-5 years from baseline (age 18-30, 1985-86) through Year 25 (2010-11). We estimated poor cognition using cognitive domain scores ≥1SD below the mean from tests of processing speed (Digit Symbol Substitution Test), executive function (Stroop) and memory (Rey Auditory Verbal Learning Test) at Year 25. Using adjusted logistic regression models, we examined the odds associated with poor midlife cognition and smoking trajectories (reference never smokers, n=1726) from early adulthood to midlife. Results: Five smoking trajectories emerged over 25-years: quitters (20%, 20/100), and minimal stable (40%, 40/100), moderate stable (20%, 20/100), heavy stable (15%, 15/100) and heavy declining smokers (5%, 5/100). As shown in the Figure, heavy stable smokers demonstrated poor cognition on all 3 domains compared to never smokers. Compared to never smokers, both heavy declining and moderate stable smokers exhibited slower processing speed, and heavy declining smokers additionally demonstrated poor executive function. For minimal stable smokers and quitters, no association was observed. Conclusions: In conclusion, we observed a dose-dependent association between early to midlife smoking and cognitive health risk at midlife. Our results underscore the cognitive health risk of moderate and heavy smoking trajectories in early and midlife periods and highlight the potential benefits of quitting, even in midlife.

Research on parallel principal component analysis based on ternary optical computer

Principal component analysis (PCA) is a widely used algorithm in the field of artificial intelligence and statistical analysis. When dealing with a large number of high-dimensional data, the traditional PCA algorithm has some shortcomings, such as slow processing speed, high power consumption, low computational efficiency. By taking advantage of several characteristics which include large number of data bits, easy-expansion of data bits, and parallel computing in ternary optical computer (TOC), the implementation scheme of parallel PCA algorithm is studied. Through the analysis of the traditional PCA algorithm, the parallel parts are found out and parallel design is carried out. Then, the elaborate implementation flow of the algorithm is given, and the clock cycle and hardware resources of the algorithm are also analyzed. Finally, the validity of the parallel scheme is proved by experiments. Compared with the traditional PCA algorithm, the PCA algorithm based on TOC has better time performance, operational efficiency, and gives full play to the advantage of ternary optical computer in processing complex computation.

Examining cognitive speed and accuracy dysfunction in youth and young adults with pediatric-onset multiple sclerosis using a computerized neurocognitive battery.

We evaluated performance on the Penn Computerized Neurocognitive Battery (PCNB), a tool assessing accuracy and response time across four cognitive domains, alongside the Symbol Digit Modalities Test (SDMT), a measure of processing speed commonly used in MS. We determined whether performance decrements are more likely to be detected on measures of accuracy versus response time in pediatric-onset multiple sclerosis (POMS). Performance on the SDMT, accuracy on PCNB tests belonging to four domains (executive function, episodic memory, complex cognition, social cognition), and response time on the PCNB were compared for 65 POMS patients (age range: 8-29 years) and 76 healthy controls (HCs) by ANCOVA. Associations between the Overall PCNB score and SDMT were examined for both groups, and their agreement in classifying impairment was assessed using Cohen's kappa. POMS patients (age at testing = 18.3 ± 4.0 years; age at POMS onset = 14.9 ± 2.3 years) demonstrated reduced accuracy relative to HCs on tests of working memory, attention/inhibition, verbal memory, and visuospatial processing, after adjusting for response time (p ≤ .002). Patients demonstrated slower overall response time on the PCNB (p = .003), while group differences on the SDMT did not meet significance (p = .03). Performance on the PCNB and SDMT were correlated (MS: r = 0.43, HC: r = 0.50, both p < .001), however, the degree of agreement for impairment was minimal (k = 0.22, p = .14). Specific cognitive deficits exist independently of slowed information processing speed in POMS, and may represent more significant areas of dysfunction. Delineation of accuracy and response time in neuropsychological assessment is important to identify areas of cognitive deficit in POMS. (PsycInfo Database Record (c) 2021 APA, all rights reserved).

Strain and sex differences in somatosensation and sociability during experimental autoimmune encephalomyelitis

Multiple Sclerosis (MS) is an immune-mediated disease that results in major locomotor deficits. However, recent studies have revealed that fatigue, slow processing speed, and memory impairment are the top variables impacting employment status for MS patients. These suggest that cognitive effects may have a greater impact on productivity, lifestyle, and quality of life than do disease-related motor deficits. However, these debilitating non-locomotive effects have been largely overlooked in rodent models of the disease, such as experimental autoimmune encephalomyelitis (EAE). We hypothesized that murine EAE can also be used to assess non-locomotive dysfunctions (mood, sociability, muscle strength, and balance), as well as potential biases in these dysfunctions due to sex and/or strain. We actively immunized male and female C57BL/6 (B6) and SJL mice for EAE and evaluated their performance on the Deacon's weight grip test, Kondziela's inverted screen test, Hall's rope grip test, manual von Frey test for somatic nociception, and a three-chamber social preference paradigm. We hypothesized that EAE progression is associated with changes in muscle strength, balance, pain, and sociability and that these variations are linked to sex and/or strain. Our results indicate that strain but not sex influenced differences in muscle strength and balance during EAE, and both sex and strain have an impact on mechanical nociception, regardless of EAE disease status. Furthermore, both sex and strain had complex effects on differences in sociability. In conclusion, testing these additional modalities during EAE helps to unveil other signs and symptoms that could be used to determine the efficacy of a drug or treatment in the modulation of a MS-like behavior.

Disentangling Within- and Between-Person Effects During Response Inhibition in Obsessive-Compulsive Disorder.

Background: Obsessive-compulsive disorder (OCD) has been related to worse performance, abnormal brain activity, and functional connectivity during response inhibition. Whether these findings are indications of stable traits that contribute to the development of the disorder, or whether they are a result of the state severity of obsessions and anxiety, remains unclear since previous research mainly has employed cross-sectional designs. The present study aimed to assess longitudinal between- and within-person relationships between symptoms, task performance, right inferior frontal gyrus brain activation, and connectivity between the right amygdala and the right pre-supplementary motor area in 29 OCD patients before and after concentrated exposure and response prevention treatment.Method: Patients received exposure and response prevention delivered during 4 consecutive days, following the Bergen 4-day Treatment format. Patients performed a Stop Signal Task during 3T functional Magnetic Resonance Imaging the day before treatment, as well as 1 week and 3 months after treatment completion. Multilevel models were used to analyze disaggregated within- and between-person effects over time. Independent variables were scores on the symptom severity scales for OCD, anxiety, depression, and state distress during scanning. Dependent variables were reaction time for go trials, stop signal response time, task-related brain activation and connectivity.Results: A positive between-person effect was found for obsessive-compulsive, anxiety, and depressive symptom severity on go trial reaction time, indicating that patients with higher symptom scores on average respond slower during accurate go trials. We also found no significant between- or within-person relations between symptom severity and task-related activation or fronto-limbic connectivity.Conclusions: The between-person findings may point toward a general association between slower processing speed and symptom severity in OCD. Longitudinal studies should disaggregate between- and within-person effects to better understand variation over time.

Deep phenotyping of symptom domains in late-life depression associated with distinct cognitive and disability profiles

Deep phenotyping of symptom domains in late-life depression associated with distinct cognitive and disability profiles

The Effects of Accelerated Brain Aging on the Antidepressant Response in Late-Life Depression

Introduction Late-Life Depression (LLD) is characterized by functional and structural brain alterations and accelerated brain aging. Our past work utilized a brain-based marker of accelerated aging to examine LLD and demonstrated a cross-sectional association between accelerated brain aging and impaired cognitive ability (poor episodic memory, slow processing speed, and poor executive function) as well as disability (measured by WHODAS). However, it is unclear whether or not accelerated brain aging influences the antidepressant response in depressed elders. Methods We examined depressed adults over 60 years-old with current Major Depressive Disorder (MDD) without psychotic features (N=95) randomized to receive either escitalopram up to 20mg daily or identical placebo (2:1 subject ratio) for 8 weeks. Subjects underwent baseline depression assessment (MADRS) and MRI prior to randomization. After using an automated deep learning tool to estimate brain age from cranial MRI, the brain age gap (BAG) was calculated by subtracting the participant's chronological age from his or her calculated brain age estimation. The brain MRI estimating tool uses ROI volumes derived from multiple atlases and the BrainAGE algorithm - the algorithm applies a deep convolutional neural network regression model trained on 5000 healthy controls. For statistical analysis, the dependent outcome variable was change in MADRS over 8 weeks. Initial models examined the effects of BAG with baseline MADRS, age, sex, and treatment assignment as covariates. Subsequent models tested for a statistical interaction between treatment assignment and BAG to observe whether or not the effects of brain aging on change in MADRS differed between arms. Results In the primary effects model examining change in MADRS, although there was a strong effect of treatment assignment (t = -3.75, p = 0.0003), there was no significant relationship between BAG and antidepressant response (t = -0.02, p = 0.9819). In the subsequent model, we observed a statistical interaction between BAG and treatment assignment on change in MADRS (t = -2.38, p = 0.0196). Analysis of subgroup data demonstrated that a larger BAG (indicating an older appearing brain) was associated with less change in MADRS for those who received placebo. In contrast, a larger BAG (indicating an older appearing brain) was associated with greater change in MADRS for those who received escitalopram. Conclusions The effect of accelerated brain aging, measured with the BAG, on change in MADRS have opposite patterns based on treatment assignment. Although a larger BAG is associated with poorer cognitive performance and greater disability, a larger BAG was associated with greater change in MADRS in the active treatment arm of our study. This is somewhat discrepant with prior work that associates poor cognitive performance with worse antidepressant response. As a global brain metric, BAG is not specific to discrete functional and/or structural brain impairments. Therefore, the elements that jointly contribute to the brain age metric may act in discrete, separate ways, with some influencing cognitive performance, and with others having less of a functional impact, serving as a marker of positive response to antidepressant medication. Further work must examine the complex relationships between accelerated brain aging, cognition, and response to antidepressants. Funding R01 MH102246, K24 MH110598

The Role of Processing Speed and Cognitive Control on Word Retrieval in Aging and Aphasia.

Purpose When speakers retrieve words, they do so extremely quickly and accurately-both speed and accuracy of word retrieval are compromised in persons with aphasia (PWA). This study examined the contribution of two domain-general mechanisms: processing speed and cognitive control on word retrieval in PWA. Method Three groups of participants, neurologically healthy young and older adults and PWA (n = 15 in each group), performed processing speed, cognitive control, lexical decision, and word retrieval tasks on a computer. The relationship between word retrieval speed and other tasks was examined for each group. Results Both aging and aphasia resulted in slower processing speed but did not affect cognitive control. Word retrieval response time delays in PWA were eliminated when processing speed was accounted for. Word retrieval speed was predicted by individual differences in cognitive control in young and older adults and additionally by processing speed in older adults. In PWA, word retrieval speed was predicted by severity of language deficit and cognitive control. Conclusions This study shows that processing speed is compromised in aphasia and could account for their slowed response times. Individual differences in cognitive control predicted word retrieval speed in healthy adults and PWA. These findings highlight the need to include nonlinguistic cognitive mechanisms in future models of word retrieval in healthy adults and word retrieval deficits in aphasia.

Age differences in risk taking: now you see them, now you don’t

ABSTRACT Older age has often, but not always, been associated with less risk taking. Inconsistencies may be due to diversity in the risk-taking measures used and/or individual differences in cognitive abilities. We investigated the robustness of age differences in risk taking across three measures, and tested whether age differences in risk taking remained after accounting for cognitive abilities. Younger (aged 25–36) and older (aged 60+) adults completed behavioral (i.e., Balloon Analogue Risk Task, BART) and self-report (i.e., framing tasks and Choice Dilemmas Questionnaire) measures of risk, as well as several measures of cognitive ability (i.e., analytic thinking, numeracy, processing speed, memory, and attention). Older adults showed significantly less risk taking than younger adults on the behavioral measure of risk, but not on the two self-report measures. Older adults also had significantly lower analytic thinking, slower processing speed, and worse executive control compared to younger adults. Less risk taking on the BART was associated with lower analytic thinking and numeracy, slower processing speed, and worse shifting of attention. Age differences in risk taking on the BART remained after accounting for older adults’ lower scores on tests of cognitive abilities. Implications for measuring age differences in risk taking are discussed.

Improving neurocognitive testing using computational psychiatry—A systematic review for ADHD.

Computational models, in conjunction with (neuro)cognitive tests, are increasingly used to understand the cognitive characteristics of participants with attention-deficit/hyperactivity disorder (ADHD). We reviewed 50 studies from a broad range of cognitive tests for ADHD to synthesize findings and to summarize the new insights provided by three commonly applied computational models (i.e., diffusion decision models, absolute accumulator models, ex-Gaussian distribution models). Four areas are discussed to improve the utility of (neuro)cognitive testing for ADHD: (a) the requirements for appropriate application of the computational models; (b) the consideration of sample characteristics and neurophysiological measures; (c) the integration of findings from cognitive psychology into the literature of cognitive testing to reconcile mixed evidence; and (d) future directions for the study of ADHD endophenotypes. We illustrate how computational models refine our understanding of cognitive concepts (slow processing speed, inhibition failures) presumed to characterize ADHD. We also show that considering sample characteristics and integrating findings from computational models and neurophysiological measures provide evidence for ADHD endophenotype-specific cognitive characteristics. However, studying the cognitive characteristics of ADHD endophenotypes often lies beyond the scope of existing research for three reasons: some cognitive tests lack sensitivity to detect clinical characteristics; analysis methods do not allow the study of subtle cognitive differences; and the precategorization of participants restricts the study of symptom severity on a continuous spectrum. We provide recommendations for cognitive testing, computational modeling, and integrating electrophysiological measures to produce more valuable tools in research and clinical practice (above and beyond the research domain of ADHD). (PsycInfo Database Record (c) 2021 APA, all rights reserved).

Associations of Salivary Total Antioxidant Capacity With Cortical Amyloid-Beta Burden, Cortical Glucose Uptake, and Cognitive Function in Normal Aging.

Determining susceptibility to Alzheimer's disease (AD) in asymptomatic individuals requires from noninvasive, simple, and inexpensive markers that can be easily obtained in primary care settings. While saliva meets all these requirements, there is a lack of evidence linking salivary constituents to in vivo AD pathology in aging. We examined the potential of salivary total antioxidant capacity (TAC) for identifying global cortical amyloid-beta (Aβ) burden, deficits in regional glucose uptake, and poorer cognition in 71 cognitively normal older adults. We further assessed whether salivary TAC-related cognitive performance was associated with higher Aβ load and lower cortical glucose consumption. Linear regression analyses adjusted by age, sex, years of education, and ApoE4 status showed that salivary TAC was associated with slower processing speed and poorer sustained attention, as well as with higher Aβ load and lower glucose metabolism in cortical regions vulnerable to cognitive aging and AD. Results also revealed that lower scores in processing speed and sustained attention were associated with greater Aβ burden and lower regional glucose consumption, respectively. Together, these findings support the use of salivary TAC for preventive screening and detection of cerebral vulnerability to AD. Further research is needed to evaluate the utility of salivary TAC as a clinical marker.

Generalized neurocognitive impairment in individuals at ultra-high risk for psychosis: The possible key role of slowed processing speed.

ObjectiveWidespread neurocognitive impairment is well‐established in individuals at ultra‐high risk (UHR) for developing psychoses, but it is unknown whether slowed processing speed may underlie impairment in other neurocognitive domains, as found in schizophrenia. The study delineated domain functioning in a UHR sample and examined if neurocognitive slowing might account for deficits across domains.MethodsThe cross‐sectional study included 50 UHR individuals with no (n = 38) or minimal antipsychotic exposure (n = 12; mean lifetime dose of haloperidol equivalent = 17.56 mg; SD = 13.04) and 50 matched healthy controls. Primary analyses compared group performance across neurocognitive domains before and after covarying for processing speed. To examine the specificity of processing speed effects, post hoc analyses examined the impact of the other neurocognitive domains and intelligence as covariates.ResultsUHR individuals exhibited significant impairment across all neurocognitive domains (all ps ≤ .010), with medium to large effect sizes (Cohen's ds = −0.53 to −1.12). Only processing speed used as covariate eliminated significant between‐group differences in all other domains, reducing unadjusted Cohen's d values with 68% on average, whereas the other domains used as covariates averagely reduced unadjusted Cohen's d values with 20% to 48%. When covarying each of the other domains after their shared variance with speed of processing was removed, all significant between‐group domain differences remained (all ps ≤ .024).ConclusionSlowed processing speed may underlie generalized neurocognitive impairment in UHR individuals and represent a potential intervention target.