Executive Function Deficits Research Articles

Biomarker-guided neuromodulation aids memory in traumatic brain injury

Traumatic brain injury (TBI) is a leading cause of cognitive disability in adults, often characterized by marked deficits in episodic memory and executive function. Prior studies have found that direct electrical stimulation of the temporal cortex yielded improved memory in epilepsy patients, but it is not clear if these results generalize to patients with a specific history of TBI. Here we asked whether applying closed-loop, direct electrical stimulation to lateral temporal cortex could reliably improve memory in a TBI cohort. Among a larger group of patients undergoing neurosurgical evaluation for refractory epilepsy, we recruited a subset of patients with a history of moderate-to-severe TBI. By analyzing neural data from indwelling electrodes as patients studied and recalled lists of words, we trained personalized machine-learning classifiers to predict momentary fluctuations in mnemonic function in each patient. We subsequently used these classifiers to trigger high-frequency stimulation of the lateral temporal cortex (LTC) at moments when memory was predicted to fail. This strategy yielded a 19% boost in recall performance on stimulated as compared with non-stimulated lists (P = 0.012). These results provide a proof-of-concept for using closed-loop stimulation of the brain in treatment of TBI-related memory impairment.

A pilot exploration of ADHD symptoms in hoarding disorder: Co-occurring disorders or part of the hoarding syndrome?

Symptoms of ADHD are common in individuals with hoarding disorder (HD). It remains unclear whether these attentional symptoms reflect high co-occurrence rates of ADHD and HD, or whether inattentive symptoms can be conceptualized as intrinsic to the HD syndrome. In addition, inattention (vs. hyperactivity) in particular, appears to be related to HD, but this may be because some inattention criteria (e.g., losing items, disorganization) may be better explained as a result of clutter rather than inattention per se. We explored what specific ADHD symptoms were most likely to be endorsed by individuals with HD, and compared this to a sample of patients with OCD (who have been shown to have some overlapping executive functioning deficits) and a sample of healthy controls. We also examined retrospective ratings of childhood ADHD symptoms to explore whether childhood ADHD symptoms were associated with later HD diagnosis, or whether attentional symptoms in HD onset later in life. Individuals with HD reported higher ADHD symptoms in childhood than did individuals with OCD, and for both clinical groups ADHD symptoms appeared to worsen across the lifespan. Individuals with HD were more likely than were individuals with OCD and healthy controls to endorse inattention subscale items, although the few hyperactive subscale items that were significant appeared to largely reflect verbal impulsivity (e.g., interrupting others, talking too much, “blurting out” responses preemptively). Specific criteria endorsed varied by diagnosis, suggesting that individuals with HD may have a different, specific inattention profile.

Functional and structural lesion network mapping in neurological and psychiatric disorders: a systematic review.

The traditional approach to studying the neurobiological mechanisms of brain disorders and localizing brain function involves identifying brain abnormalities and comparing them to matched controls. This method has been instrumental in clinical neurology, providing insight into the functional roles of different brain regions. However, it becomes challenging when lesions in diverse regions produce similar symptoms. To address this, researchers have begun mapping brain lesions to functional or structural networks, a process known as lesion network mapping (LNM). This approach seeks to identify common brain circuits associated with lesions in various areas. In this review, we focus on recent studies that have utilized LNM to map neurological and psychiatric symptoms, shedding light on how this method enhances our understanding of brain network functions. We conducted a systematic search of four databases: PubMed, Scopus, and Web of Science, using the term "Lesion network mapping." Our focus was on observational studies that applied lesion network mapping in the context of neurological and psychiatric disorders. Following our screening process, we included 52 studies, comprising a total of 6,814 subjects, in our systematic review. These studies, which utilized functional connectivity, revealed several regions and network overlaps across various movement and psychiatric disorders. For instance, the cerebellum was found to be part of a common network for conditions such as essential tremor relief, parkinsonism, Holmes tremor, freezing of gait, cervical dystonia, infantile spasms, and tics. Additionally, the thalamus was identified as part of a common network for essential tremor relief, Holmes tremor, and executive function deficits. The dorsal attention network was significantly associated with fall risk in elderly individuals and parkinsonism. LNM has proven to be a powerful tool in localizing a broad range of neuropsychiatric, behavioral, and movement disorders. It holds promise in identifying new treatment targets through symptom mapping. Nonetheless, the validity of these approaches should be confirmed by more comprehensive prospective studies.

Executive functions and borderline personality features in adolescents with major depressive disorder.

Executive functions (EF) consolidate during adolescence and are impaired in various emerging psychiatric disorders, such as pediatric Major Depressive Disorder (pMDD) and Borderline Personality Disorder. Previous studies point to a marked heterogeneity of deficits in EF in pMDD. We examined the hypothesis that deficits in EF in adolescents with pMDD might be related to comorbid Borderline Personality features (BPF). We examined a sample of 144 adolescents (15.86 ± 1.32) diagnosed with pMDD. Parents rated their child's EF in everyday life with the Behavior Rating Inventory of Executive Function (BRIEF) and BPF with the Impulsivity and Emotion Dysregulation Scale (IED-27). The adolescents completed equivalent self-rating measures. Self- and parent-ratings of the BRIEF scores were compared with paired t-Tests. Correlation and parallel mediation analyses, ICC, and multiple regression analyses were used to assess symptom overlap, parent-child agreement, and the influence of depression severity. Over the whole sample, none of the self- or parent-rated BRIEF scales reached a mean score above T > 65, which would indicate clinically impaired functioning. Adolescents tended to report higher impairment in EF than their parents. Depression severity was the strongest predictor for BPF scores, with Emotional Control predicting parent-rated BPF and Inhibit predicting self-rated BPF. Furthermore, the Behavioral Regulation Index, which includes EF closely related to behavioral control, significantly mediated the relationship between depression severity and IED-27 factors emotional dysregulation and relationship difficulties but not non-suicidal self-injuries. On average, adolescents with depression show only subtle deficits in executive functioning. However, increased EF deficits are associated with the occurrence of comorbid borderline personality features, contributing to a more severe overall psychopathology. Therefore, training of executive functioning might have a positive effect on psychosocial functioning in severely depressed adolescents, as it might also improve comorbid BPF. www.ClinicalTrials.gov, identifier NCT03167307.

Awareness of Disease and Its Domains in Young-onset and Late-onset Dementia: The Role of Executive Function.

Executive function (EF) involves a general cognitive process linked to strategic organization and control of complex goal-oriented tasks. In young-onset dementia (YOD), especially Alzheimer's disease, the symptoms that stand out in the initial stage are deficits in attention, visual-spatial function, praxis, and language. The present study aims to investigate what components of EF differ in young and late-onset dementia (LOD) and its impact on awareness and its domains. Using a cross-sectional design, we included 44 people with YOD and 70 with LOD. We assessed awareness and its domains, cognition, dementia severity, EF, functionality, and neuropsychiatric symptoms. The YOD group was more impaired in general cognition ( P =0.017) and had a worse performance in Wechsler Digit Span Backward (DSB) ( P =0.007) and Phonemic fluency task (FAS) ( P =0.046) tests. In the LOD group, deficits in EF had a greater impact on awareness and on most domains (awareness total score, cognitive functioning and health condition, functional activity impairments and social function). Our study findings support the heterogeneity of awareness, not only with regard to the difference between the domains and the measures of EF, but also to the groups studied.

Executive Functions: What are they Good for? A Perspective from Intervention Research

ABSTRACTBecause deficits in executive functions (EFs) characterize most neurodevelopmental disorders, it is appropriate to question the value of EFs for understanding learning disabilities. Two types of studies—those testing whether EFs moderate treatment effects and those testing the direction of effects between EFs and academic skills—are presented to support the idea that EFs are useful for the study of learning disabilities in the context of intervention. Moderator effects in reading and math intervention studies suggest that considering EFs to be properties of not only persons, but also interventions is important for understanding treatment effects and for designing more effective interventions. An experimental study comparing math word problem solving interventions and EF interventions provides evidence for bidirectional development of working memory and math word problem solving. Directions for future experimental research that systematically and more rapidly investigate growth in EFs and academic skills in individuals with learning disabilities are presented.

Does Cognitive Impairment Impact Motor Learning? A Scoping Review of Elderly Individuals With Alzheimer's Disease and Mild Cognitive Impairment.

Individuals with cognitive impairment may have motor learning deficits due to the high engagement of cognitive mechanisms during motor skill acquisition. We conducted a scoping review to address the quality of current research on the relationship between cognitive impairments (i.e., deficits in attention, memory, planning and executive functions) and motor learning among older adults with Alzheimer's Disease or Mild Cognitive Impairment. After screening thousands of articles, we selected 15 studies describing cognitive assessment tools, experimental designs, and the severity of cognitive impairment. Although seven studies reported that cognitive impairment impaired motor learning, most studies included a high risk of bias. We identified multiple assessment tools across these studies that make comparisons among findings difficult. Future research in this area should focus on the influence of increased practice days during motor learning acquisition and incorporate both retention and transfer tests. Cognitive assessments should target the specific cognitive skills or deficits most closely related to the motor learning process.

Association of Bilateral Vestibulopathy With and Without Hearing Loss With Cognitive-Motor Interference

The past years, evidence suggested that the primary symptoms traditionally associated with bilateral vestibulopathy (BV) do not represent the full picture of this patient population. Recent literature also demonstrated cognitive impairment. However, although multitasking and dual-tasking are widely present in everyday activities, most of these studies assessed cognitive function only in single-task conditions. To uncover the association of BV with and without hearing loss with cognitive and motor performance and cognitive-motor interference. This prospective case-control study assessed persons with an isolated BV and persons with BV and a concomitant hearing loss compared with a healthy control group. Data were analyzed in December 2022. The study was conducted at Ghent University (Ghent, Belgium). Data collection took place between March 26, 2021, and November 29, 2022. All participants completed the 2BALANCE dual-task protocol, comprising a static and a dynamic motor task that was combined with 5 visual cognitive tasks. These cognitive tasks assessed mental rotation, visuospatial memory, working memory, response inhibition (executive function), and processing speed. All cognitive tasks were performed in a single-task condition (while seated) and in a dual-task condition (combined with a static and a dynamic motor task). The static task comprised balancing on a force platform with foam pad, and the dynamic task comprised walking at a self-selected speed on the GAITRite Walkway. Both motor tasks were performed in the single-task and dual-task condition. Nineteen persons with BV and hearing loss (mean [SD] age, 56.70 [10.12] years; 10 women [52.6%]), 22 persons with an isolated BV (mean [SD] age, 53.66 [13.35] years; 7 women [31.8%]), and 28 healthy control participants were included (mean [SD] age, 53.73 [12.77] years; 12 women [42.9%]). Both patient groups had mental rotation and working memory impairment in a single-task condition and slower processing speed when walking (ie, during the dynamic dual-task condition). Additionally, the patient group with hearing loss had impaired visuospatial memory and executive function deficits in single-task and dual-task conditions, while this could only be elicited when performing a motor task in persons with isolated BV (ie, when dual-tasking). The findings of this case-control study suggest an association between vestibular function and cognitive and motor performance, even greater in persons with a concomitant hearing loss than in persons with an isolated BV.

Eye movement changes as an indicator of mild cognitive impairment.

Early identification of patients at risk of dementia, alongside timely medical intervention, can prevent disease progression. Despite their potential clinical utility, the application of diagnostic tools, such as neuropsychological assessments and neuroimaging biomarkers, is hindered by their high cost and time-consuming administration, rendering them impractical for widespread implementation in the general population. We aimed to develop non-invasive and cost-effective classification models for predicting mild cognitive impairment (MCI) using eye movement (EM) data. We collected eye-tracking (ET) data from 594 subjects, 428 cognitively normal controls, and 166 patients with MCI while they performed prosaccade/antisaccade and go/no-go tasks. Logistic regression (LR) was used to calculate the EM metrics' odds ratios (ORs). We then used machine learning models to construct classification models using EM metrics, demographic characteristics, and brief cognitive screening test scores. Model performance was evaluated based on the area under the receiver operating characteristic curve (AUROC). LR models revealed that several EM metrics are significantly associated with increased odds of MCI, with odds ratios ranging from 1.213 to 1.621. The AUROC scores for models utilizing demographic information and either EM metrics or MMSE were 0.752 and 0.767, respectively. Combining all features, including demographic, MMSE, and EM, notably resulted in the best-performing model, which achieved an AUROC of 0.840. Changes in EM metrics linked with MCI are associated with attentional and executive function deficits. EM metrics combined with demographics and cognitive test scores enhance MCI prediction, making it a non-invasive, cost-effective method to identify early stages of cognitive decline.

#5133 MONTREAL COGNITIVE ASSESSMENT (MOCA) AND DYSMORPHIC RED BLOOD CELLS IN PATIENTS WITH IMMUNOGLOBULIN A NEPHROPATHY

Abstract Background and Aims Patients with chronic kidney disease (CKD) are at an increased risk of cognitive dysfunction, which is characterized by deficits in executive functions, memory and attention. Previous studies have suggested that albuminuria and lower estimated glomerular filtration rate (eGFR) are related to mild cognitive impairment (MCI) and dementia. There are no studies that have noticed connection between glomerular activity presented by dysmorphic red blood cells (RBC) count and cognitive evaluation results. The aim of the study was to investigate the association of cognitive decline with renal function and other possible risk factors such as albuminuria, proteinuria, and hematuria in patients with immunoglobulin A nephropathy (IgAN). Method A prospective study that took place from January 2020 till January 2022 at Pauls Stradins Clinical University Hospital Nephrology center included patients with IgAN. Diabetes mellitus, oncology, acute inflammation processes, transplantation in anamnesis were exclusion criteria. Demographic, anamnestic, clinical, laboratory data for renal function evaluation were collected. GFR was calculated using CKD-EPI Creatinine Equation. Urine spot protein/creatine ratio was used for proteinuria measurement. Urine microscopy was performed by a nephrologist. Patients were assessed with a MoCA. Results of MoCA have been compared with potential risk factors. Results Sixty-five patients were included in the study. The mean age of the participants was 42.06 ± 10.71 years (IQR 35-47.75; range, 21-65), with predominance of male sex (62.1%), mainly with higher education (45.5%). Dialysis was performed in 7 patients. The average duration of illness was 89.97 months ± 97.95 (IQR 31.5-120, range 1-456 months/38 years). Average GFR was 59.26 ± 38.66 (IQR 20.25-91.75, range 3-131) ml/min/1,73m2, urea 12.57± 9.88 (IQR 6.3-15.45, range 4-62). Patients did not have anemia, average hemoglobin 135.20± 14.8. Average proteinuria was 0.53±0.99 g/g (IQR 0.064-0.52, range 0.06-6.20), albuminuria - 69.34±107.3 g/mol (IQR 10.95-69.4, range 0.45-620). Average hematuria was 116.68±239.67 RBC/mkl (IQR 9.9-92.1, range 1.5-1421.3), while dysmorphic RBC count was 4.02±12.08 RBC/hpf (IQR 0-2.5, range 0-80). MoCA ≤ 26 was observed in 41% of the patients. The MoCA total score have moderate correlation with the patients age (p = 0.01, r = -0.39). Patients age correlated with memory task score (p = 0.002, r = -0.42). Dysmorphic RBC count in urine sediment corelated with attention task (p = 0.002, r = -0.42). Conclusion Mild cognitive impairment is frequent even in our young age IgAN patient's cohort. Even small age difference plays role in MoCA evaluation score. No correlations have been found between proteinuria or albuminuria and MoCA score. Association between dysmorphic RBC and cognitive decline should be studied in bigger cohorts’ studies.

Does the Frontal Brain Electrical Activity Mediate the Effect of Home Executive Function Environment and Screen Time on Children’s Executive Function?

Executive functions play an important role in various developmental aspects of children; however, environmental factors influencing individual differences in children’s executive function and their neural substructures, particularly in middle childhood, are rarely investigated. Therefore, the current study aimed to investigate the relationship between the home executive function environment (HEFE) and screen time with the executive function of children aged 8-12 years by employing the mediating variables of alpha, beta, and theta waves. The parents of 133 normal children completed Barkley Deficits in Executive Functioning, HEFE, and Screen Time Scales. Alpha, beta, and theta brain waves were also measured. Data were examined using correlational and path analysis. The results suggested a positive and significant relationship between home executive functions and the executive functions of children. Furthermore, the results indicated an inverse and significant relationship between screen time and executive function. The results also proved the mediating role of alpha, beta, and theta brain waves in the relationship between screen time and the children’s executive function. Environmental factors (such as home environment and screen time) affect the function of brain waves and, thus, the daily executive function of children.

Cognitive Functional Remote Group intervention for adults with attention deficit hyperactivity disorder: A feasibility study

Introduction: Attention deficit hyperactivity disorder among adults has been associated with deficits in executive functioning and poor quality of life. The purpose of this study is to examine feasibility of the Cognitive Functional Remote Group intervention among adults with attention deficit hyperactivity disorder. Method: Mixed-method feasibility study. Five adults with attention deficit hyperactivity disorder received 16 weekly sessions of Cognitive Functional Remote Group. Results: The target population was easily recruited and showed interest in the treatment. All participants completed the intervention and were moderately-very highly satisfied with different aspects of the intervention. Additionally, pre–post measures demonstrated high rates of clinically significant improvements in the quality of life measure and less so in executive functioning. Three central themes emerged from qualitative analyses of participants experiences relating to (a) Identity development through group process; (b) Occupation-based learning of self-awareness and cognitive functional strategies and (c) Feedback on group setting and content and relating to advantages and disadvantages of remote (Zoom) format. Conclusion: This study supported Cognitive Functional Remote Group feasibility among adults with attention deficit hyperactivity disorder. Quantitative findings point to the responsiveness of quality-of-life measures. Qualitative findings suggest gains in identity development, awareness and acquisition of cognitive functional strategies through occupation-based learning in a telerehabilitation group therapy format. Further controlled studies are warranted.

A Verbal Card Sorting Task to Measure Executive Functions.

The Wisconsin Card Sorting Test (WCST) is commonly used to measure nonverbal executive functions (EFs) in a variety of clinical populations. However, in some clinical populations (e.g., people with aphasia), deficits may be present in more linguistic (or verbal) domains and less pronounced in nonverbal domains. Thus, when determining possible deficits in these individuals, it is critical to assess both verbal and nonverbal cognitive abilities. The purpose of this study was to create a verbal card sorting task (VCST) to complement the WCST. We created the VCST by modifying a computerized version of the WCST, the Berg Card Sorting Task (BCST). We then compared 35 individuals with mild traumatic brain injury (mTBI) and 33 matched controls' performance on each task. We tested the VCST in individuals with mTBI first because they demonstrate impaired EFs but unimpaired language. We therefore expected the mTBI group to perform similarly on the VCST and BCST, suggesting that the two tasks measure EFs similarly. In line with our hypothesis, the mTBI group had unimpaired inhibition and sustained attention but impaired shifting on each task. Component loadings for both tasks were also similar, and participants' inhibition and shifting scores positively correlated across the two tasks. Together, these findings suggest that the VCST is a potentially useful tool for measuring verbal EF deficits. Our results also provide important insights into the EF impairments experienced by individuals with mTBI. https://doi.org/10.23641/asha.23230475.

Assessing the Relationships Between Paranormal Beliefs, Higher-Order Cognitive Processes, Delusions, and Hallucinations in A Non-Clinical Population

Previous studies suggest that paranormal beliefs, cognitive processes, and psychotic-like experiences are correlated. To further explore this connection, research was conducted to examine whether paranormal beliefs were correlated with, or predicted by executive functioning, metacognition, delusions, and hallucinations. A convenience sample of 180 people completed five measures- evaluating paranormal beliefs, executive functioning deficits, metacognition awareness, delusions, and hallucinations. Prior to performing correlation and multiple regression analyses, the reliability of each measure was assessed. Findings revealed the significant positive correlations of paranormal beliefs with deficits in executive functioning, delusions, and hallucinations, whilst no significant correlation was found with metacognition. Regression analysis showed that delusions and hallucinations were significant predictors of paranormal beliefs. Concerning the relevant literature, these outcomes are debated.

Brain-Cognition Associations in Older Patients With Remitted Major Depressive Disorder or Mild Cognitive Impairment: A Multivariate Analysis of Gray and White Matter Integrity

BackgroundAlmost half of older patients with major depressive disorder (MDD) present with cognitive impairment, and one-third meet diagnostic criteria for mild cognitive impairment (MCI). However, mechanisms linking MDD and MCI remain unclear. We investigated multivariate associations between brain structural alterations and cognition in 3 groups of older patients at risk for dementia, remitted MDD (rMDD), MCI, and rMDD+MCI, as well as cognitively healthy nondepressed control participants. MethodsWe analyzed magnetic resonance imaging data and cognitive domain scores in participants from the PACt-MD (Prevention of Alzheimer’s Disease With Cognitive Remediation Plus Transcranial Direct Current Stimulation in Mild Cognitive Impairment and Depression) study. Following quality control, we measured cortical thickness and subcortical volumes of selected regions from 283 T1-weighted scans and fractional anisotropy of white matter tracts from 226 diffusion-weighted scans. We assessed brain-cognition associations using partial least squares regressions in the whole sample and in each subgroup. ResultsIn the entire sample, atrophy in the medial temporal lobe and subregions of the motor and prefrontal cortex was associated with deficits in verbal and visuospatial memory, language skills, and, to a lesser extent, processing speed (p < .0001; multivariate r = 0.30, 0.34, 0.26, and 0.18, respectively). Widespread reduced white matter integrity was associated with deficits in executive functioning, working memory, and processing speed (p = .008; multivariate r = 0.21, 0.26, 0.35, respectively). Overall, associations remained significant in the MCI and rMDD+MCI groups, but not the rMDD or healthy control groups. ConclusionsWe confirm findings of brain-cognition associations previously reported in MCI and extend them to rMDD+MCI, but similar associations in rMDD are not supported. Early-onset and treated MDD might not contribute to structural alterations associated with cognitive impairment.

The combined effect of β ‐amyloid and white matter hyperintensities on present and future executive function performance in cognitively normal older adults

AbstractBackgroundβ‐amyloid (Aβ) and White matter hyperintensities (WMH) are key drivers of cognitive decline in healthy older adults and both are considered biomarkers of preclinical dementia. Deficit in executive function (EF) linked to WMHs and Aβ burden, have been shown to predict the development of dementia. The present study aimed to explore the interactions of regional and global Aβ with WMH on baseline and longitudinal performance in EF in cognitively normal (CN) older adults.MethodGlobal and regional Standard Uptake Value ratios (SUVr) from Aβ‐PET, WMH volumes from MRI FLAIR images, and composite scores of EF at baseline and after approximately 2 years were analyzed across a sample of 714 clinically‐normal (Mini‐Mental State Examination (MMSE) ≥ 26), aged participants from the Alzheimer’s Disease Neuroimaging Initiative (ADNI2). We used multiple regression models including the interaction tem and main effects for Aβ and WMH to investigate the independent and combined associations of these pathologies with EF. Age, ApoE, education, baseline EF score, and time to follow up EF testing were entered as covariates in the regression models.ResultThe moderation regression analysis showed that additive effects on Aβ burden and WMH in relation to baseline EF with p value for the interaction term between the two pathologies 0.07, and significant interaction effects of global, frontal and cingulate Aβ burden, and WMH in relation to longitudinal EF performance with p values of 0.037, 0.03, and 0.032 respectively. The main effect from regression analysis demonstrated that baseline EF performance was predicted by the combination of Aβ burden and WMH, while Aβ burden was the only predictor for longitudinal EF performance.ConclusionThese data demonstrated that baseline Aβ and WMHs have both independent effects on EF scores at baseline and synergistic effects on longitudinal EF performance. The biological relationships and interplay between Ab and WMH responsible for the synergistic effects seen on longitudinal EF performance warrants further study.

Using the clock drawing test to differentiate impairments in executive functioning between Alzheimer’s Dementia and Parkinson’s disease

AbstractBackgroundPrevious studies suggest the usefulness of CDT in distinguishing between neurodegenerative diseases. The purpose of this study was to examine differences in CDT performance in individuals with AD and PD compared to normal controls.MethodsTotal of 194 participants. Four groups included in analysis: patients that met diagnostic criteria for late MCI/mild AD, moderate AD, PD with no cognitive impairment, and normal controls. All participants completed MMSE and CDT. MMSE score ≤ 23 considered moderate AD, MMSE score &gt;24 considered mixed late MCI/mild AD, all PD patients had MMSE score &gt;24.ResultsAn ANOVA was used to examine group differences in CDT and MMSE scores. There was a significant main effect of group for both CDT and MMSE scores (p &lt; 0.001). Moderate AD group had significantly lower MMSE scores compared to other groups (average MMSE score of 19.4 for moderate AD compared to 26.6 for mild AD, 26.9 for Parkinson’s, and 28.2 for controls). Post‐hoc t‐tests (Bonferroni corrected for multiple comparisons) showed moderate AD group had significantly higher error scores on CDT compared to controls (p&lt;0.001). Moderate AD group also had significantly higher error score compared to both MCI/mild AD and PD patient groups (p&lt;0.001). No statistical significance existed in error scores between MCI/mild AD group compared to controls (p = 0.134) or to Parkinson’s disease (p = 1.000). No statistical significance in CDT error scores between the Parkinson’s group compared to controls (p = 0.904). Findings suggest executive functioning may only begin to significantly decline in advanced stages of AD.ConclusionOur findings suggest that deficits in executive functions measured by CDT is impaired in moderate AD but relatively preserved in MCI/mild AD and PD with no cognitive impairment, which is consistent with previous studies. One limitation of the study is that we did not include a copy trial for the CDT, which may support that our findings are due to executive dysfunction rather than visuospatial deficits. Future directions include increasing sample sizes, including individuals with PD with cognitive impairment, and using novel digital versions of the CDT to different variables of the CDT such as time to start and complete, visuospatial coordination, and graphic size.

Related amyloid burden and cortical atrophy in individuals with subtle cognitive decline

AbstractBackgroundSubtle cognitive decline represents a stage of subclinical cognitive deterioration in which pathological biomarkers, particularly for Alzheimer’s disease may be present, including early cortical atrophy and amyloid deposition. Using individual items from the Montreal Cognitive Assessment (MoCA) and k‐modes cluster analysis, we previously identified three distinct cognitive clusters of individuals without overt cognitive impairment, which comprised a High Performing cluster (no deficits in performance), a Memory Deficits cluster (lower memory performance), and a Compound Deficits cluster (lower memory and executive function performance). In this study, we sought to understand the different relationships found in our clusters between cortical atrophy on MRI and B‐amyloid burden on PET.MethodsData was derived from the Alzheimer’s Disease Neuroimaging Initiative and comprised individuals with Clinical Dementia Rating of 0 with available MRI and 18‐Florbetapir B‐amyloid PET data (n = 272). Using multiple group structural equation modeling, we regressed amyloid standardized uptake value ratio (PET) on volumetric regions (MRI). Models were constrained to test significance of associations across groups defined by cognitive clusters.ResultsIn our Compound Deficits cluster, greater whole cerebral B‐amyloid burden was significantly related to atrophy of the right entorhinal cortex and left hippocampus, with regression coefficients of ‐0.412 (p = 0.005) and ‐0.304 (p = 0.049), respectively. Within this cluster, right entorhinal cortical atrophy was significantly related to greater amyloid burden within multiple frontal lobe regions.ConclusionsThe Compound Deficits cluster, which represents a group at higher risk of decline with deficits in both memory and executive function, was observed to have significantly more cortical atrophy, particularly within the entorhinal cortex and hippocampus, associated with whole brain and frontal lobe B‐amyloid burden. These findings, which are consistent with the neuropsychological deficits observed on the MoCA in this cluster, point to a pattern of early pathological deterioration that may place these individuals at risk for future decline.

Síndrome de temblor y ataxia asociado a frágil X (FXTAS): revisión de la literatura

El síndrome de temblor y ataxia asociado al síndrome del cromosoma X frágil (FXTAS) es un desorden neurodegenerativo progresivo (1), de inicio tardío, que ocurre entre los portadores de la premutación del gen FMR1 (Fragile X Mental Retardation 1), el cual está estrechamente asociado con el síndrome del cromosoma X frágil (FXS). El FXTAS se caracteriza por déficits neurológicos que incluyen temblor de intención progresivo, ataxia cerebelosa, parkinsonismo, neuropatía periférica, déficits cognitivos y disfunción autonómica (2-4).&#x0D; El FXTAS surge como una importante opción diagnóstica en hombres con temblor, alteraciones en la marcha y síntomas neurodegenerativos. En general existe subregistro de esta patología dado que es un síndrome recientemente descrito y falta conocimiento de los profesionales de salud al respecto, los cuales, debido a la similitud de su presentación clínica con otros desórdenes neurológicos, generalmente suelen confundir el diagnóstico (5).&#x0D; En Colombia no se ha documentado la prevalencia de SXF o de FXTAS. Sin embargo, se ha descrito un corregimiento en el Valle del Cauca que tiene una prevalencia de más de cien veces lo reportado en la literatura de SFX, lo que nos sugiere que en Colombia existe subregistro del SFX y de FXTAS.&#x0D; Esta revisión tiene por objeto difundir los avances del conocimiento de las manifestaciones clínicas, la neurofisiopatología y las posibilidades de tratamiento de los pacientes con FXTAS, y así aumentar diagnóstico y aportar a mejorar la calidad de vida de los afectados y de sus familias.

Executive functions and emotion regulation in children with autism spectrum disorders

ABSTRACT Children with autism spectrum disorders (ASD) present deficits in regulation of their emotions which have a great impact on their mental health and well-being. There are several studies showing the connection between executive functions deficits and emotion dysregulation in the context of an ASD diagnosis. Our study aims to investigate which among the executive functions can predict the emotional dysregulation in children with ASD, if there is an association between the ASD specific characteristics and their ability to regulate their emotions and to identify if there are possible mediators of this relationship. To reach our objective, we enrolled 60 children with ASD (mean age 8.5 years) whose parents completed standardised measurements for executive functions, emotional dysregulation, and ASD characteristics. We found a positive association between ASD characteristics’ severity and emotional dysregulation, as well as some significant predictors among specific executive functions and emotional dysregulation. Moreover, executive functioning mediates the relationship between the ASD characteristics and emotion regulation. Our research provides a better understanding of the relationship between ASD characteristics, executive functions, and emotion regulation.