Evidence exists that cocaine impacts cognition and behaviour. Yet, uncertainty remains as to what extent cognitive inhibition efficiency decreases in cocaine users. We carried out a systematic review and meta-analysis following the PRISMA 2020 checklist. Our search yielded 1725 articles from Scopus, PubMed and WOS, from which twenty-four studies were finally identified as meeting the inclusion criteria for the systematic review and twenty (providing twenty-three effect sizes) for the meta-analysis. A multi-level random-effects meta-analysis was conducted, and moderation analysis was implemented to examine the potential moderating effects of sex, age, years of regular cocaine use, days of cocaine abstinence, and sample type (clinical vs. community) in the estimated effects. Results showed worse inhibition in cocaine users compared to controls (g = 0.65; 95% CI [0.28, 1.03], p < .001), but none of the moderators significantly impacted this effect. Findings highlight the link between impaired cognitive inhibition and cocaine use disorder and suggest that inhibitory control training approaches would be promising. Future clinical studies are needed to elucidate on the efficacy of neuropsychological approaches for improving inhibitory control and augment the effectiveness of first-line interventions for cocaine use disorder.

Executive functions and self-regulation, which are the control processes relevant for learning and adaptation, are frequently impaired in neurodevelopmental disorders (NDDs). Research on the role of early executive functions and self-regulation in the diagnosis and developmental trajectories of NDDs has grown rapidly in recent years, necessitating a synthesis of the evidence strength and the methodologies used to investigate the relationship between executive functions/self-regulation and the functional profiles of NDDs. This systematic review and meta-analysis examined 32 studies that used longitudinal designs to investigate the relationship between executive functions and self-regulation in the first 6 years of life and NDDs symptoms from ages 3 to 18. Separate meta-analyses were conducted for the statistical methods used, as well as for ADHD and ASD diagnoses, types of executive function and self-regulation measures, and the developmental periods during which they were assessed. The results highlight a significant longitudinal association between early executive and self-regulation difficulties and later impairments in attention, socio-communication, and adaptive functioning in NDDs. The findings also support the predictive value of these early difficulties and the need to consider the methodological characteristics of the studies. Although these findings predominantly concern specific diagnostic categories, such as attention-deficit/hyperactivity disorder and autism spectrum disorder, they could have important implications for several conditions of atypical neurodevelopment, especially for the prevention of symptoms and associated psychopathological exacerbation. Given the methodological variability of the studies, the results of this review can also help in defining more appropriate tools and statistical methodologies for future research.

This systematic review aimed to identify preserved and impaired memory processes in Huntington's disease (HD), with consideration of disease stage and the specific memory subsystems assessed. A systematic search was conducted in PubMed, ScienceDirect, and Google Scholar up to March 11, 2025. Eligible studies had to be peer-reviewed, had to involve participants aged 18 or older, had to include patients with genetically or clinically confirmed HD, and had to be published in English or French. Risk of bias was assessed using the ROBINS-I tool. A structured narrative synthesis was performed across seven memory subsystems and clinical stages (pre-manifest vs. manifest), and findings were summarized using tables and figures. A total of 136 studies were included. Verbal episodic memory impairments were consistently observed from early stages, particularly in free recall, while recognition was initially preserved. Visual episodic memory showed progressive deficits. Olfactory memory, though rarely examined, appeared to be impaired early. Autobiographical memory was underinvestigated but showed signs of disruption, seemingly independent of executive dysfunction. Semantic memory was generally preserved but showed reduced access without cues. Early-stage impairments were also reported in working memory. Priming was preserved, while complex procedural learning tasks showed variable deficits. Many studies presented methodological limitations, including confounding and lack of blinding. Memory profiles in HD appear heterogeneous and subsystem-specific. Autobiographical memory may constitute a distinct cognitive marker. Improved characterization of memory deficits is crucial to guide the development of targeted cognitive interventions.

This meta-analysis estimated academic achievement differences between children and adolescents with and without Neurofibromatosis type 1 (NF1) and explored potential moderators. Systematic literature searches from inception to March 2025 identified 2,531 unique articles, with 39 studies (146 effect sizes) met inclusion criteria. These studies encompassed data from 3,681 individuals with NF1 (43.95% female; M = 10.50 years, SD = 2.53) and 15,153 without NF1 (48.92% female; M = 9.85 years, SD = 3.03). Group differences in academic achievement (Hedges' g) were synthesized using robust standard error estimation and random effect models. Individuals with NF1 exhibited lower achievement in reading (g = -0.79, 95% CI [-0.95, -0.64]), writing (g = -0.82, 95% CI [-0.95, -0.68]), and math (g = -0.77, 95% CI [-0.90, -0.65]). Group disparities were present across reading subskills with greater differences in pseudoword reading (g = -1.43, 95% CI [-1.98, -0.89]) and word reading (g = -0.96, 95% CI [-1.26, -0.67]) than reading fluency (g = -0.62, 95% CI [-1.00, -0.23]). Lower full-scale IQ and verbal IQ were linked to greater group disparities in writing, but not in reading or math. Disparities were greater when unaffected siblings were used as controls (vs. normative data) in reading and writing. These findings underscore the need for targeted support and educational interventions for individuals with NF1.

Mild cognitive impairment (MCI) represents an intermediate stage between typical aging and early cognitive decline. As such, an early and accurate diagnosis is essential in making timely interventions. Digital tools, including mobile applications, web platforms, wearable devices, and artificial intelligence-driven systems, have been developed and validated to capture multidimensional data, offering innovative screening solutions. This meta-analysis aims to evaluate the diagnostic accuracy of digital tools for MCI detection in different populations and settings, with a particular focus on three key issues: (i) the overall diagnostic performance of digital tools, (ii) the influence of methodological quality of studies, and (iii) the impact of demographic factors and familiarity with technologies on diagnostic accuracy. This meta-analysis assessed diagnostic accuracy across 32 studies, reporting pooled sensitivity (0.808, 95% CI: 0.775-0.838) and specificity (0.795, 95% CI: 0.757-0.828), but with considerable heterogeneity (I = 71.5% sensitivity; 84.0% specificity). The HSROC analysis revealed significant intrinsic variability (τₐ = 0.807) and minimal threshold variability (τθ = 0.291). Meta-regression indicated that applicability concerns significantly reduced specificity (p = 0.037), with older age also predicting lower specificity (p = 0.029). Thus, implementing standardized protocols, rigorous validation processes, and targeted adaptations are crucial steps for enhancing the effectiveness of digital tools in detecting MCI.

This meta-analysis evaluated the effectiveness of neuropsychological interventions in enhancing cognition in patients with epilepsy. The systematic review was conducted under PRISMA guidelines. Of 1363 articles, 25 met the inclusion criteria. Meta-analyses assessing pre-post changes in experimental interventions (i.e., without comparison to control groups) revealed moderate effects on cognition in adults (g = 0.29; 95% CI = 0.18, 0.40; p < 0.0001), with significant effects for attention (g = 0.24; 95% CI = 0.06, 0.43; p = 0.0098), immediate memory (g = 0.34; 95% CI = 0.21, 0.47; p < 0.0001), delayed memory (g = 0.38; 95% CI = 0.18, 0.57; p < 0.0001), and language (g = 0.33; 95% CI = 0.06, 0.59; p = 0.0159). In pediatric samples, moderate effects were found on overall cognition (g = 0.55; 95% CI = 0.22, 0.89; p = 0.0012), with gains in attention (g = 0.66; 95% CI = 0.15, 1.17; p = 0.01) and working memory (g = 0.80; 95% CI = -0.05, 1.65; p = 0.06). Comparisons with control groups (i.e., patients without intervention) showed a trend towards positive effects in adults (g = 0.35; 95% CI = -0.00, 0.71; p = 0.053), with brain training games associated with poorer outcomes (B = -1.03; SE = 0.52; 95% CI = -2.05, -0.00; p = 0.049). No significant differences were found in pediatric samples (g = 0.34; 95% CI = -0.22, 0.89; p = 0.24). The findings support the implementation of targeted cognitive interventions in clinical practice, offering evidence-based recommendations.

The autobiographical functioning of memory allows the grouping of all personal knowledge. Patients with Alzheimer's disease (AD) exhibit autobiographical recall disorders due to difficulties in retrieving contextual elements associated with personal memories. This impairment leads to a reduction in the subjective experience of recall as well as a disturbance of self-awareness. Within an innovative approach, this article aims to reconsider the autobiographical recall deficits observed in AD according to the embodied approach to cognition, in order to promote the development of embodied interventions aimed at reducing the difficulties of patients with AD. To this end, we propose two preliminary models: the first concerning autobiographical recall disorders in AD according to the embodied approach to cognition, and the second concerning the management of autobiographical recall disorders in AD according to the embodied approach to cognition. We thus propose avenues for reflection and a reference framework for clinicians and researchers wishing to develop embodied methods intended for AD patients.

Despite compelling evidence that cognitive interventions for older adults improve cognition, mood, and everyday function, few are implemented in clinical or community practice. This scoping review aims to understand the implementation frameworks and methods used and their contribution to implementation success of cognitive interventions for older adults. We followed the Preferred Reporting Items for Systematic Reviews and Meta-analysis extension for Scoping Reviews (PRISMA-ScR), and searched CINAHL, EMBASE, MEDLINE, and PSYCINFO databases, using terms related to cognitive interventions, implementation, and older adults. This resulted in 5002 studies, of which 29 were included following an iterative process. Most studies reported on implementation of cognitive stimulation for people with dementia. Only four studies used formal implementation frameworks, with three using RE-AIM, and one a process evaluation using complexity theory. The most frequently addressed implementation concepts were Acceptability, Feasibility, and Effectiveness, while Cost, Cost-Effectiveness, and Maintenance were rarely reported. Solutions to common barriers included the importance of good stakeholder relationships and engagement, a manualised intervention flexible enough to adapt to the context, and ensuring facilitators were well-trained, confident, and enthusiastic.

Acquired brain injury can result in disability with direct and indirect consequences for psychosocial functioning. Psychosocial interventions embedded within traditional neurorehabilitation may provide a valuable buffer. While there is evidence of benefits associated with group-based psychosocial interventions, there is no single recommended intervention, despite several different approaches having been trialled. This systematic review aimed to provide a critical appraisal of existing group psychosocial interventions in neurorehabilitation, meta-analyse their efficacy, and explore the contribution of group process to outcomes. Eligible studies were published in English-language peer-reviewed journals and recruited adults with acquired brain injury in receipt of group psychosocial interventions. Outcomes of interest were depression, anxiety, quality of life, emotional distress, community integration, and social support. A systematic search of CINAHL, PsycINFO, Medline, Web of Science and Embase from database inception until 08.07.2024 was conducted. Risk of bias was assessed using the Effective Public Health Practice Project Quality Assessment Tool for Quantitative Studies. Effect sizes were calculated using Hedges' g and estimated using a three-level random effects model. Sixty-five studies were included in the systematic review, and 48 were included in the meta-analysis (n = 2653). There was an overall small effect on psychosocial outcomes (Hedges' g = 0.24, 95% CIs [0.16, 0.33]), though none of the included studies satisfactorily analysed group process despite 70% of these studies proclaiming their importance. Overall, there were mixed findings across intervention type and significant heterogeneity. Recommendations for future psychosocial group interventions in neurorehabilitation are provided.

This meta-analysis estimated the group differences between individuals with and without neurofibromatosis type 1 (NF1) and explored potential moderators. Systematic literature searches identified 2531 unique articles. Among them, 70 studies (183 effect sizes) were included in this meta-analysis, involving 3503 individuals' visuospatial and visuomotor abilities with NF1 (46.67% female; M = 12.60 years) and 3127 individuals without NF1 (52.40% female; M = 13.19 years). Robust standard error estimation techniques and random models were used to calculate standardized group differences. The results showed that individuals with (vs. without) NF1 exhibited significantly lower visuospatial (g =  - 0.90; 95% CI [- 1.00, - 0.80], I = 64.59%) and visuomotor abilities (g =  - 0.90; 95% CI [- 1.05, - 0.75], I = 74.87%). The moderator analysis revealed that group differences in visuospatial abilities were larger for children with NF1 (g =  - 0.95; 95% CI [- 1.06, - 0.84]) than adolescents (g =  - 0.64; 95% CI [- 0.91, - 0.37]) and adults (g =  - 0.73; 95% CI [- 0.88, - 0.58]). Additionally, a greater between-group difference was found when visuospatial abilities were assessed using Judgment of Line Orientation (g =  - 1.06; 95% CI [- 1.17, - 0.94]) than Wechsler Intelligence Scale-Visual Spatial Index (g =  - 0.70; 95% CI [- 0.86, - 0.54]). Sex composition, NF1 inheritance mode, IQ, learning disorder, ADHD, types of control group, sampling method, and exclusion criteria of NF1 participants were not significant moderators. The substantial visuospatial and visuomotor deficits in the NF1 population highlight the necessity for targeted interventions, and considerable between-study heterogeneity underscores that further exploration of predictors is needed.

This systematic review investigates the long-term trajectories of depressive symptoms in individuals with acquired brain injury (ABI) and identifies factors predicting group membership in these trajectories. The review follows the PRISMA guidelines and is registered on the International Platform of Registered Systematic Review and Meta-analysis Protocols (INPLASY-2023-11-0013). A comprehensive search of MEDLINE, PSYCINFO, EMBASE, CINHALPlus, ScienceDirect, Scopus, and Web of Science identified peer-reviewed studies published in English on adults aged 16 and above with an ABI diagnosis. Studies were included if they used a validated depression measure, had at least three assessment points, and applied group-based trajectory modelling. Exclusion criteria included studies focusing on neurodegenerative or neurodevelopmental disorders, or solely on treatments. The methodological quality was assessed using Joanna Briggs' critical appraisal tool. The review synthesised data from ten studies involving 13,205 participants (average age 51.38 years, 55.86% male). Four depressive symptom trajectory groups were identified with varying prevalence: stable low (68%), persistent high (13%), increasing (20%), and decreasing (11%). Several key predictors including sex, age, injury severity, and education emerged as significant predictors of group membership in the persistent high, increasing, and decreasing depressive groups. However, variability in study methodologies and sample compositions posed challenges to direct comparison. Nonetheless, the review underscores the importance of long-term monitoring and the development of tailored interventions, as depression can manifest or intensify years post-injury. Understanding depressive symptom trajectories could help create personalised interventions, improving quality of life for those with depression after ABI.

Dynamic functional connectivity (dFC) methods could shift understandings about brain-behavior relationships. Information processing speed (IPS) may be of particular interest to dFC analyses as dFC is able to capture time-sensitive FC changes. The present systematic review aims to explore the association between IPS and dFC of resting-state functional magnetic resonance imaging (rsfMRI) data in healthy individuals. Included papers were published through July 24, 2023. Searches conducted on ProQuest and ScienceDirect used the search terms processing speed AND fMRI AND resting state AND dynamic functional connectivity OR dynamic functional network connectivity. Studies were eligible based on the following inclusion criteria: empirical research, published in English, use of a well-characterized healthy population (n > 30), use of rsfMRI, calculation of dFC, measurement of IPS, and a statistical test between dFC and IPS. Results reveal mixed findings. Five studies report no relationship between dFC and IPS, whereas eight report mixed or positive findings. We noted several trends in findings that may be driving inconsistencies. Over half of the reviewed studies used the Human Connectome Project data. Second, IPS was more likely to be related to dFC if images were acquired using an eyes open procedure with fixation on a crosshair. As all included IPS measures involved a visual component, IPS and dFC measurement might both be capturing information about visuoperceptual connections. Future work that addresses these biases and trends may illuminate the nature of the relationship between dFC and IPS.

Episodic memory impairment can persist in persons with HIV (PWH) despite treatment. Depression is among the most prevalent comorbidities in HIV. Changes to brain regions involved in episodic memory like the hippocampus and the prefrontal cortex have been well documented in depression. If episodic memory changes occur in PWH, it is important to understand the potential impact of concurrent depressive symptoms (DS). Thus, our objective was to conduct a systematic review and meta-analysis on the role of DS in episodic memory in PWH. We included cross-sectional and longitudinal studies that provided episodic memory test scores and a formal assessment of DS expecting that episodic memory in PWH (A) be lower with comorbid DS; (B) negatively correlated with DS severity and incidence of clinical depression; and (C) declines over time with comorbid depression. Following PRIMSA guidelines, 3505 papers were identified, of which 44 studies were ultimately included. Meta-analysis demonstrated that immediate but not delayed recall were lower in PWH with DS than without DS, with small average effect sizes. An inverse relationship between DS severity and episodic memory performance emerged in about a quarter of the studies, with a higher likelihood in studies measuring incidence of clinically elevated DS. If observed, longitudinal memory decline was limited to moderately-severely depressed PWH. Our results suggest that prevention and treatment of clinical levels of depressive symptomatology in PWH remains a paramount target in HIV care with important implications for memory and likely other cognitive functions long-term.

The National Institutes of Health Toolbox Cognition Battery (NIHTB-CB) is an assessment tool that has been widely utilized in research with clinical populations across the lifespan. Despite its widespread use, a systematic review and meta-analysis of cognitive function utilizing this battery in clinical samples has not been reported. To address this gap, 84 studies were identified after systematically searching PsycINFO, PubMed, and ProQuest (71 peer-reviewed articles, 11 dissertations, 2 master's theses) comprising 6331 clinical participants. Study quality was assessed using the QUADAS-2 tool. Results identified significant deficits in the Fluid Cognition Composite and the associated subtests (attention, working memory, processing speed, executive function) in clinical samples when compared to both the NIHTB-CB normative data and recruited comparison samples. Unexpectedly, there was some evidence that clinical participants scored higher on Crystallized Cognition subtests than the normative data but scored significantly lower than recruited controls. There was mixed evidence for performance differences on a Total Cognition Composite measure of cognitive function. There was some evidence of publication bias, and results were moderated by study quality and participant demographics. The implications of the findings for clinical research settings are discussed and suggested future directions are provided.

Neuropsychological testing is an essential tool in clinical settings engaged in detecting, treating, or preventing neurocognitive disorders around the world. There is a need for accurate norms across cultures, including Latinx/Hispanic communities. We reviewed studies published in English or Spanish focused on acquiring normative data for Spanish-speaking individuals in the United States (U.S.), Latin America and the Caribean (LAC), and Spain. We searched available studies from Embase, PubMed, PsycINFO APA, Science Direct, and ProQuest up to October 31, 2024. Studies were imported to COVIDENCE and reviewed by two Spanish-English bilingual reviewers and one proficient English reviewer. Ultimately, 75 articles were included and categorized into U.S. (n = 23), LAC (n = 21), Spain (n = 23), and multiregional (n = 8) based. Overall, most studies included a cognitively normal/healthy sample to establish the normative data, adjusting or stratifying for age, education, and sex. In Spanish speakers, cognitive performance improved with advancing age in children and adolescents and declined with age in adults. Higher education was also associated with better performance on tests across regions. While this review highlights the increasing accumulation of norms for Spanish-speaking populations, there is a continued need to expand norms to other Spanish-speaking populations not included in this analysis. Future research should add variables, such as acculturation and bilingualism, to aid normative rigor. This review works as a tool to facilitate and improve the understanding of current normative data.

The Iowa Gambling Task (IGT) is a popular measure of risky decision-making, but to date, no formal quantitative reviews have been conducted, focused exclusively on IGT performance amongst individuals with acquired brain injury (ABI). Therefore, this meta-analytic study firstly explored performance differences between individuals with ABI vs controls. Second, we extended this comparison by investigating differences in IGT scoring and interpretive approaches (e.g., total score vs later block analysis). Finally, we explored potential IGT performance moderators (e.g., average age). A total of 25 studies, containing 39 samples (total n = 2188), were included. Overall findings suggested that the IGT is sensitive to the presence of ABI, particularly non-TBI and medically confirmed TBI, which becomes evident by block 2 of 5. Medium effect sizes were obtained for IGT total score, as well as indicators using later blocks only. Performance moderators such as population type and region influenced IGT performance, whilst average age, average education, and proportion of males did not. These results indicate that the IGT is sensitive to decision-making impairment following ABI, although we conclude that further research is needed to confirm the IGT's ability to detect impairment relative to specific brain regions.

The Bayesian framework conceptualizes human perception as a process of probabilistic inference, where the brain integrates prior expectations with incoming sensory evidence to construct a mental model of the world. Within this framework, several distinct theories-collectively termed the "simple Bayesian model"-suggest that perceptual atypicalities in autism stem from an imbalance between the precision of prior beliefs and sensory input. This study presents a systematic review and the first meta-analysis to evaluate empirical evidence for the simple Bayesian model. We synthesized 24 effect sizes from 23 eligible studies using a random-effects model to test its core predictions: that autistic individuals exhibit universally "broader" priors and/or heightened sensory precision compared to non-autistic controls. We found a significant, small-to-moderate overall effect in the predicted direction (Hedge's g = 0.37). However, heterogeneity across studies was large and significant and was not explained by any of the examined moderators: prior type (structural vs. contextual), stimulus type (social vs. nonsocial), task setting (implicit vs. explicit), cognitive domain (higher-level cognition vs. perception), or participant characteristics. Given the significant unexplained heterogeneity, our findings offer only limited support for a universal "simple Bayesian model" of autism. We conclude that future research should move beyond the simple Bayesian model to investigate more sophisticated, hierarchical Bayesian accounts of autism.

Empathy is the ability to recognise, share and understand others' emotional states. Increasing evidence suggests that empathy may be impacted by acquired brain injury (ABI), with consequences for social and emotional functioning. However, the literature has been characterised by inconsistent findings and small sample sizes. To address these limitations, we provide the first meta-analytic review of empathy in adults with ABI. Specifically, the review aimed to quantify the degree of impairment in adults with ABI across four empathy-related domains: cognitive, affective, empathic concern (e.g. sympathy) and personal distress. We also sought to estimate the prevalence of deficits in each area and explore whether demographic and injury factors moderate impairment. A systematic search yielded 29 studies measuring self-reported empathy in adults with ABI versus healthy, matched peers. A series of random-effects meta-analyses revealed moderate deficits in cognitive empathy (Hedges' g =  - 0.68, 95% CI [- 0.87, - 0.50]) and affective empathy (Hedges' g =  - 0.43, 95% CI [- 0.65, - 0.21]), as well as small-to-moderate deficits in empathic concern (Hedges' g =  - 0.38, 95% CI [- 0.63, - 0.13]). No significant difference was found for personal distress. We estimated the proportion of ABI participants scoring equal to or more than 1 SD below the normative mean to be 15.3-35.0%, depending on the empathy subcomponent. Our results highlight that empathy deficits may play an important role in functional or emotional difficulties post-brain injury. This demonstrates the need for routine clinical assessment of empathy in survivors of brain injury and the need to develop interventions which target both cognitive and affective components.

Alzheimer's is a progressive disease, with a long preclinical phase of many decades. Accurate classification within longitudinal cohort studies is crucial for understanding disease progression and for the comparability and collaboration across studies. The main objective of this systematic review was to identify and compare the diagnostic criteria used in prospective population study cohorts centering on the Alzheimer's disease clinical continuum in older adults. A review was performed of cohort studies started in the year 2000 or later, with a follow-up duration of at least 3 years among people aged between 50 and 85 years old living in the community. Original studies were searched in MEDLINE, Embase, Cochrane, PsycINFO, and Web of Science. Two independent reviewers agreed on the final selection of 28 studies covering 25 cohorts. One study was identified by three independent judges as having methodological limitations due to inadequate reporting as per the modified NIH quality assessment tool. Data was extracted from each included study using a standardized extraction form. In general, the studies followed fewer than 1500 participants. The results showed convergence in the choice of diagnostic classification criteria among the 25 cohorts studied especially for the later stages of AD, while criteria for the earliest stages showed greater variability. Only five cohorts studied were concerned with the follow-up of the full spectrum of the disease. Our study may help to put in place a unified set of clinical diagnostic criteria across the continuum of Alzheimer's disease, rather than criteria developed specifically for a given study.

A longstanding issue concerns the extent to which episodic autobiographical memory (EAM) and episodic future thinking (EFT) are the expression of the same cognitive ability and may be dissociated at the neural level. Here, we provided an updated picture of overlaps and dissociations between brain networks supporting EAM and EFT, using Activation Likelihood Estimation. Moreover, we tested the hypothesis that spatial gradients characterize the transition between activations associated with the two domains, in line with accounts positing a transition in the relative predominance of their features and process components. We showed the involvement of a core network across EAM and EFT, including midline structures, the bilateral hippocampus/parahippocampus, angular gyrus and anterior middle temporal gyrus (aMTG) and the left superior frontal gyrus (SFG). Contrast analyses highlighted a cluster in the right aMTG significantly more activated during EFT compared with EAM. Finally, gradiental transitions were found in the ventromedial prefrontal cortex, left SFG, and bilateral aMTG. Results show that differences between EAM and EFT may arise at least partially through the organization of specific regions of common activation along functional gradients, and help to advocate between different theoretical accounts.

The purpose of this systematic review was to synthesize the current evidence on motor learning in mild cognitive impairment (MCI). A search of five databases returned a total of 6058 references, 10 of which met criteria for inclusion in this review. The existing evidence was notably variable with an overall moderate risk of bias. Eight articles compared behavioral motor learning outcomes in MCI and age matched, non-cognitively impaired (NCI) samples. In 37.5% of these studies, the degree of motor skill acquisition in the MCI group was statistically significantly less than in the NCI group. Skill retention was only compared between MCI and NCI samples in one article, which reported a relative reduction in MCI group performance following a 24-h, no-practice delay. Importantly, none of the included articles examined motor skill transfer. We discuss possible sources of heterogeneity among collective findings including variability in motor tasks, outcome measurement, and research design. Further research is needed to support a comprehensive understanding of motor learning in the early stages of age-related cognitive decline. Future investigations should emphasize functional motor tasks and clinically relevant learning outcomes, including retention and transfer of motor skills, while controlling for potentially confounding factors such as motivation and sleep performance. This systematic review was registered with PROSPERO international prospective register of systematic reviews (registration ID CRD42023417329).

Developmental topographical disorientation (DTD) refers to a condition of highly impaired navigation ability in healthy individuals. DTD often leads to severe consequences in daily life, affecting education and professional choices and limited everyday mobility. Since its first description in 2009, a substantial number of empirical studies on DTD have appeared, but a clear clinical definition of DTD that can be used to develop a behavioral assessment tool is not yet available. The aim of the current study was to shed more light on the precise behavioral characteristics of DTD by examining the empirical evidence available to date. Recent theoretical developments that enable the classification of navigation impairment in various populations are utilized in the current work. Through a systematic literature review, reported descriptions and criteria for DTD were identified. Furthermore, tests included and performance of people with DTD are classified in the different navigation domains relevant to navigation impairment (landmark knowledge; location knowledge, egocentric and allocentric; and path knowledge, route and survey). A total of 15 empirical papers were included in the analyses, each discussing performance of people with DTD in large-scale spatial tasks. Initial DTD descriptions focused on mental map quality, whereas later work adheres to a more general definition of impaired navigation. Performance patterns show that the navigation impairment in DTD is largely attributable to low mental map quality, as low performance is primarily found for tasks measuring allocentric location knowledge and path knowledge. In contrast, landmark knowledge remains largely unaffected and, if impaired, appears to also include face recognition impairment, suggesting a more general form of visual agnosia. Egocentric location knowledge is often not included in assessments. The outcomes support the initial focus on poor mental map quality as the key characteristic of DTD, combined with a landmark-focused navigation strategy. The current findings therefore provide relevant input to the development of a clinical characterization of DTD and the development of appropriate assessment tools.

The aging population is increasing the prevalence of dementia, neurodegenerative disorders, and mild cognitive impairment, which are associated with cognitive declines in executive functioning. In people with these disorders, accurate tests can aid in the early detection of executive functioning decline and facilitate access to interventions. The Hayling and Brixton tests (HBTs) are popular executive functioning tests that assess inhibitory control. The HBTs may be especially effective for detecting people with disorders that are associated with disinhibition, such as behavioral-variant frontotemporal dementia (bvFTD). However, the effectiveness of the HBTs for detecting cognitive decline in dementia, neurodegenerative disorders, and mild cognitive impairment has yet to be collated. A comprehensive search of five databases identified 50 studies that compared the HBTs performances of adults aged 40 years and over with a dementia, neurodegenerative disorder, or mild cognitive impairment (e.g., Parkinson's disease, Alzheimer's dementia, bvFTD) and cognitively-healthy controls. Hedges' g effect sizes compared groups on the five HBTs scores (Inhibition Errors, Inhibition Reaction Time (RT), Automatic RT, Inhibition minus Automatic RT, and Brixton Errors). The disorders (combined) showed negative effects on all HBTs scores (g - 0.37 to - 1.13), with dementia (combined) performing the worst (g - 0.54 to - 1.56). Automatic RT and Inhibition Errors were the most effective scores for detecting cognitive decline in dementia (g - 1.55; g - 1.34). The dementia types performed similar after outliers were removed and only studies with low risk-of-bias were analyzed. Overall, the HBTs are effective for detecting cognitive decline in middle to older aged adults, especially those with dementia. However, no score type can be recommended for differentiating the dementia types, such as AD and bvFTD.

Primary progressive aphasias (PPA) represent a group of neurodegenerative conditions affecting verbal communication abilities for which no effective medication is currently available. Noninvasive brain stimulation (NiBS) has been mainly explored as adjunctive therapy to conventional speech and language therapy (SLT) with promising results. The present meta-analysis of randomized-controlled trials (RCTs) aims to evaluate the efficacy of NiBS in PPA patients on a range of linguistic tasks (naming, phonemic fluency, semantic fluency). A literature search was carried out using EMBASE and PUBMED, searching for multi-session RCTs administering NiBS on PPA patients as stand-alone or with SLT. The results were not significant overall, indicating a null difference between the active and the sham condition on language functions; pooled effects tended to be higher in parallel than in crossover studies and for follow-ups than post-treatment. In the naming analyses, the combined effects for the studies that coupled NiBS with SLT were slightly higher than the overall effect at each time point, although not significant. These results need to be considered with caution given the low number of included studies and small sample sizes, but offer relevant indications for future research in terms of optimal treatment protocols and personalization of therapies.

CTNNB1 syndrome is a rare neurodevelopmental disorder caused by a likely pathogenic or pathogenic variant in the CTNNB1 gene. A systematic review was conducted to examine previous research that provided CTNNB1 syndrome patients, specifically those that described intellectual quotient, motor development, language impairments, behavioural problems and features of autism. Databases examined were PubMed and Scopus. The inclusion criteria were (a) reported human patients diagnosed with CTNNB1 syndrome by a genetic test; (b) were related to cognition, intelligence quotient, motor development, language impairment, behavioural problems or features of autism; (c) did not have another genetic diagnosis and (d) were written in Spanish or English. A total of 42 studies were included. Overall, the symptomatology described was very heterogeneous with varying degrees of impairment among patients. However, individuals reached most significant developmental milestones later than expected and with different degrees of impairment. The use of standardised methodology to assess cognitive and behavioural domains was scarce in most studies, and the vast majority did not include a specific assessment protocol based on the symptomatology of CTNNB1 syndrome individuals. In addition, only two adult patients were described in depth, which implies that there are many unknowns about the progression of the syndrome later in life. Therefore, future research should focus on increasing the sample assessed and count with a standardised protocol in order to characterise the cognitive and behavioural phenotype of CTNNB1 syndrome.

While Category Fluency (CF) is widely used to help profile semantic memory, item-level scoring (ILS) approaches to this test have been proposed to obtain indices that are less influenced by non-semantic supportive functions. We systematically reviewed the literature to test the hypotheses that (1) compared with healthy adults, individuals with a clinical diagnosis suggestive of neurodegeneration generate words of lower semantic complexity; (2) compared with young adults, older adults generate words of higher semantic complexity. We searched six databases (date of search: 8 December 2023) for studies that relied on CF and ILS methods, in normal ageing and in age-associated neurodegeneration. Thirty-four studies were shortlisted: 27 on neurodegenerative conditions; 7 on normal ageing. Risk of bias was evaluated via a published checklist. Data were presented via qualitative synthesis. Most studies reported words of lower semantic complexity in relation to at least one item-level feature in individuals with mild cognitive impairment (MCI), Alzheimer's dementia (AD), and other neurodegenerative diseases. Post-hoc meta-analyses focussing on the MCI/AD continuum confirmed an effect on words' frequency (385 MCI/AD individuals and 350 controls; Hedges's G = 0.59) and age-of-acquisition (193 MCI/AD individuals and 161 controls; Hedges's G =  - 1.51). Studies on normal ageing, conversely, failed to demonstrate any overall effect. Most studies on MCI and AD have not relied on neurobiological diagnostic criteria. Moreover, only a small number of studies analysed ILS controlling for quantitative CF performance. Despite these two limitations, this study suggests that ILS can contribute to an in-depth characterisation of semantic memory in neurological ageing.

There is a widespread view that episodic autobiographical memories (EAMs) can be retrieved "directly" or "generatively." However, the neural mechanisms underlying these retrieval modes have been overlooked in the literature, likely due to the difficulty of operationalizing the two notions. Here, we propose to operationalize direct vs. generative retrieval based on memory cue specificity, in terms of EAMs elicited by specific/personalized vs. generic memory cues, respectively. After completing a literature search in four databases (PubMed, Scopus, Google Scholar, Web of Science) in 2023, we performed a multilevel kernel density analysis (MKDA) to directly compare activations from 32 neuroimaging studies investigating these two EAM retrieval modalities with the above memory cue distinction. Both direct and generative retrieval showed common activations of the left hippocampus, bilateral angular gyrus, and posterior cingulate cortex. The direct vs. generative comparison revealed the activation of a brain circuit comprising the anterior and posterior cortical midline, the left angular gyrus, and the right cerebellum. Previous literature suggests that these regions play a role in self-referential processes, indicating that direct access to EAMs may be supported by the recruitment of self-related neural resources that facilitate the retrieval of personal memories. Conversely, generative vs. direct MKDA revealed the activation of the ventromedial prefrontal cortex. As this region has been previously associated with schematic memory, its involvement may emphasize the "constructive" nature of generative EAM retrieval. Overall, the current findings extend the previous literature by providing the neurobiological foundation of direct and generative EAM retrieval.

To date, few studies have focused on the benefits of dopaminergic treatment on episodic memory functions in patients affected by Parkinson's disease (PD). We conducted a meta-analysis to determine the effects of pharmacological therapy with dopamine in alleviating episodic memory deficits in Parkinson's patients. A secondary aim was to evaluate the role of dopamine in episodic memory circuits and thus in different memory systems. We conducted a comprehensive literature search in PubMed (1971-2022) to find studies that met specific inclusion criteria. The studies had to provide sufficient data (means and standard deviations) to evaluate performance on neuropsychological tests of episodic memory. A total of k = 36 measures were included in the analysis. A statistically significant difference suggested better performance following dopaminergic therapy assumption (ON condition) than following dopaminergic withdrawal (OFF condition), specifically the estimated pooled effect calculated through a random-effects restricted maximum likelihood model was log ratio of means (RoM) = 0.047 (p = 0.011). The back-transformed RoM, indicating a 4.8% improvement, provides an interpretable measure of the effect size, as it reflects the multiplicative change in performance associated with the ON condition. A meta-regression analysis was also performed to assess the influence of specific memory tasks and relevant covariates/factors on the overall meta-analytic effect: four memory contrasts (verbal/visual, immediate/delayed, recall/recognition, word-list/short-story), age of participants, years of education, severity of illness, duration of illness in years, country of study, proportion of women in the sample, type of medication, counterbalancing. Word list/short story and proportion of women in the sample were the only two statistically significant predictors in the model, both associated with a positive higher pooled effect size. The present study revealed a significant overall difference between the results obtained in the ON and OFF conditions. We also found a significantly greater pharmacological effect in the recall of short stories than word lists, which supports the hypothesis of a beneficial effect of dopamine on the hippocampal circuit rather than on prefrontal cortical areas.

Existing studies examining the predictive ability of biomarkers for cognitive outcomes do not account for variance due to measurement error, which could lead to under-estimates of the proportion of variance explained. We used data from the Alzheimer's Disease Neuroimaging Initiative (ADNI) (N = 1084) to estimate the proportion of variance explained by Alzheimer's disease (AD) imaging biomarkers in four cognitive outcomes: memory, executive functioning, language, and visuospatial functioning. We compared estimates from standard models that do not account for measurement error, and multilevel models that do account for measurement error. We also examined estimates across diagnostic subgroups (normal, MCI, AD). Estimates of the proportion of variance explained from multilevel models accounting for measurement error were larger (e.g., for language, 9-47% vs. 7-34% under standard modeling), with relatively greater differences between standard and multilevel measurement models for cognitive outcomes that have larger measurement error variance. Heterogeneity across subgroups also emphasized the importance of sample composition. Future studies should evaluate measurement error adjustments when considerable measurement error in cognitive outcomes is suspected.

Intra-individual variability (IIV) quantifies an individual's scatter in performances across a test battery (dispersion) or across reaction times within a single task (consistency). No studies have meta-analyzed the cross-sectional IIV literature in those with mild cognitive impairment (MCI) and Alzheimer's dementia (AD). An additional aim of this meta-analysis was to examine IIV in APOE ε4 + healthy control (HC) samples. A systematic search strategy was applied to six databases (Academic Search Complete, PsycINFO, MEDLINE, CINAHL Complete, ERIC, and ProQuest Dissertations & Theses) to identify studies comparing the extent of dispersion- and consistency-based cognitive IIV between clinical (MCI, AD) and HC samples. Thirty-five studies met the inclusion criteria for our random-effects cross-sectional meta-analysis. Hedges' g was used to aggregate between-group effect sizes, with higher positive values indicating clinical > HC IIV. Meta-regression and subgroup-analyses were conducted to evaluate continuous and categorical moderator variables, respectively. Omnibus models yielded analogous moderate-strength, albeit heterogeneous, effects for dispersion and consistency (g = 0.65). Clinical severity was a robust moderator of dispersion (MCI = 0.47, AD = 1.16) and consistency (MCI = 0.51, AD = 1.31) effects. Supplemental analysis of APOE ε4 status in HCs revealed a nonsignificant trend of elevated overall (i.e., dispersion + consistency) IIV in APOE ε4 + vs. APOE ε4 - HC samples (g = 0.24). Cognitive IIV is sensitive to the presence of AD-related genetic risk as well as neurocognitive impairment across the neurocognitive disorder severity spectrum, with a graded-pattern of HC < MCI < AD samples.