Visuospatial Learning Research Articles

Exploring Neurocognitive Performance Differences in Military Aviation Personnel.

INTRODUCTION: Military aeromedical evaluations are common, but specialized neuropsychological norms for aviation personnel are sparse, resulting in a need to rely on norms from the general population. Little has been published regarding aviation subpopulations and how their neuropsychological profiles may differ from general population normative data. This study investigated neuropsychological test results of aeromedical service members to evaluate consistency with general population norms, and to delineate differences between aviation subpopulations.METHODS: Analyses were conducted on demographic variables and test scores of military aviators (N 26) and nonaviator crewmembers (N 36) referred for evaluation due to a clinical problem requiring a waiver for flight status. Performance differences between subsamples were investigated with general linear modeling. Base rates for low scores were described.RESULTS: Mean test scores in both subsamples were 0 to 1 standard deviation (SD) above the general populations means, with the largest discrepancies being found on measures of visuospatial ability (crewmembers) and verbal learning (aviators). Modeling revealed a significant difference between aviators and crewmembers on Trail Making Test Part B, after accounting for education. Aviators produced fewer low scores than crewmembers, even when using education adjusted normative data.DISCUSSION: Results suggest the cognitive profile of aviators is uniquely strong in specific domains, with fewer low scores. The development of aviator-specific norms may enhance sensitivity to cognitive decrements in this population. Future studies might separately assess crewmember roles to further assess cognitive performance standards across specialties.Maltez-Laurienti A, Minniear A, Moore R, McGovern T, Newman P, Brearly T. Exploring neurocognitive performance differences in military aviation personnel. Aerosp Med Hum Perform. 2021; 92(9):702709.

A-70 Differences in Cognition and Disease Characteristics in Adult Vs. Late Onset Multiple Sclerosis

Abstract Objective Cognitive impairment is a common sequelae of multiple sclerosis(MS), however, relatively little is known about cognitive impairment in late-onset MS (LOMS; symptom onset >50 years old). The present study investigated differences in disease characteristics and cognition in LOMS and adult-onset MS (AOMS). Methods Archival medical records and neuropsychological evaluations from an MS specialty center were reviewed. Differences in disease characteristics between 57 LOMS and 124 AOMS patients were compared using chi-square or ANOVA. To investigate differences in cognitive functioning, age-adjusted standardized scores were compared via ANCOVA, using cardiac risk factors and disease duration as covariates. Results Compared to AOMS (age range: 21–88; mean age: 49.66 +/−12.83), LOMS patients (age range 42–82; mean age: 61.88 +/− 8.57) had significantly more cardiac comorbidities (mean: 1.12+/−1.1 vs. 0.6+/−0.9; p < 0.01), shorter disease duration (mean years: 13.14+/−7.9 vs. 21.0+/−12.6; p < 0.001), and shorter time to diagnosis (mean years: 3.0+/−4.2 vs 6.5+/−8.5; p < 0.01). LOMS patients had similar Expanded Disability Status Scale scores and number of prescribed disease-modifying therapy as AOMS. LOMS patients demonstrated greater impairment on Brief Visuospatial Memory Test-Revised learning (F(1,169) = 8.03, p < 0.05; d = 0.36) and delayed recall (F(1,169) = 4.44, p < 0.05; d = 0.27), and on Wechsler Adult Intelligence Scale-4th edition Digit Span Backward (F(1,176) = 5.68, p < 0.05; d = 0.41) and Sequencing (F(1, 176) = 11.90, p < 0.001; d = 0.55) subtests. Conclusion Despite a shorter disease duration and quicker diagnosis, LOMS patients demonstrate similar levels of physical impairment. Moreover, even after accounting for differences in disease duration and cardiac risk, LOMS showed a greater burden of cognitive impairment than AOMS, which taken together, suggests an elevated rate of disease progression in LOMS.

Cognitive Differences between Men and Women with HIV: A Systematic Review and Meta-Analysis.

Although many studies report that women with HIV (WWH) are more vulnerable to cognitive impairment than men with HIV (MWH), this trend is not described consistently in the literature. In this systematic review and meta-analysis, we investigated whether the weight of evidence supports the existence of a significant sex difference in cognitive functioning among people with HIV and, if so, whether specific domains are affected. A systematic literature search retrieved 4,062 unique articles published between January 2000 and June 2019. Eligibility criteria were that studies directly compared adult WWH and MWH using a neuropsychological test battery. After extensive screening, we included 11 studies in the systematic review (N = 3,333) and 6 in the meta-analysis (N = 2,852). Six studies included in the systematic review found WWH performed significantly more poorly on measures of cognitive performance than MWH; the other five found no sex differences. Meta-analytic results indicated that WWH performed significantly more poorly than MWH in three cognitive domains (psychomotor coordination, visuospatial learning, and memory), but magnitudes of effect sizes were small (d = -.16, -.43, and - .30, respectively). Analyses detected no sex differences in global cognitive functioning and in the other cognitive domains. Sex differences in cognitive performance are small, and sociodemographic and psychiatric characteristics of WWH and MWH differ between studies. Cognitive differences between WWH and MWH may be explained by sex-based variation in these characteristics, the impact of which seems to outweigh that of HIV-related clinical variables (e.g., CD4 count and viral load).

Effects of a novel M4 muscarinic positive allosteric modulator on behavior and cognitive deficits relevant to Alzheimer's disease and schizophrenia in rhesus monkey

Alzheimer's disease (AD) is a profoundly debilitating neurodegenerative disorder characterized most notably by progressive cognitive decline, but also agitation and behavioral disturbances that are extremely disruptive to patient and caregiver. Current pharmacological treatments for these symptoms have limited efficacy and significant side effects. We have recently reported the discovery of Compound 24, an M4 positive allosteric modulator (PAM) that is potent, highly selective, and devoid of cholinergic-like side effects in rats. In order to further evaluate the translatability of the effects of compound 24 in primates, here we describe the effect of Compound 24 on three behavioral and cognition assays in rhesus monkeys, the stimulant induced motor activity (SIMA) assay, the object retrieval detour task (ORD), and the visuo-spatial paired-associates learning (vsPAL) task. As far as we know, this is the first such characterization of an M4 PAM in non-human primate. Compound 24 and the clinical standard olanzapine attenuated amphetamine induced hyperactivity to a similar degree. In addition, Compound 24 demonstrated procognitive effects in scopolamine-impaired ORD and vsPAL, and these effects were of similar magnitude to donepezil. These findings suggest that M4 PAMs may be beneficial to diseases such as Alzheimer's disease and schizophrenia, which are marked by behavioral disturbances as well as deficits in cognitive function.

Assessment of chemotherapy-induced cognitive impairment: a prospective study of the cognitive effects of platinum/taxane-based chemotherapy in gynecologic cancer patients

<h3>Background:</h3> Chemotherapy-induced cognitive impairment (CICI), ‘chemo-brain,' involves concentration and executive functioning difficulty and slowed processing speed and memory. Although cognitive changes in CICI can be subtle and difficult to quantify, CICI affects up to 75% of cancer survivors and impacts quality of life. <h3>Objectives:</h3> The objective of our study was to add to the definition of CICI by quantifying changes in specific cognitive domains before and after administration of platinum/taxane-based chemotherapy in gynecologic cancer patients using a tailored battery of neurocognitive tests. <h3>Methods:</h3> Following institutional review board approval, chemotherapy-naïve gynecologic cancer patients scheduled to receive six cycles of intravenous platinum/taxane-based chemotherapy were identified. Baseline demographic, social, and clinical characteristics were obtained. Eleven neurocognitive assessments measured cognitive domains of interest (Table 1), including a brief cognitive screen, evaluation of fine motor skills, verbal fluency, working memory, information processing speed, visuospatial learning and memory, attention, mental flexibility, and abstract problem-solving skills. The European Organization for the Research and Treatment of Cancer Quality of Life Questionnaire Core-30 and Psychiatric Diagnostic Screening Questionnaire assessed emotional functioning. The Functional Assessment of Cancer Therapy - Cognitive Function assessed self-perceived cognitive functioning. Testing was performed prior to the first and three to four weeks after the last cycle of chemotherapy. Descriptive statistics identified trends in individual indices of cognitive dysfunction and quality of life. <h3>Results:</h3> Fourteen patients enrolled and nine were eligible for complete analyses. The mean age was 60.6 years. The mean full scale intelligence quotient prior to therapy was 103.5. Most patients were White (8/9, 89%), had obtained at least a Bachelor's degree (5/9, 55.6%), and were diagnosed with high grade (6/9, 66.7%) stage III or IV disease (5/9, 55.6%). The majority of patients declined on cognitive screening performance (5/9, 55.6%) as well as worse scores on indices of attention (7/9, 77.8%), mental flexibility (5/8, 62.5%) verbal learning (5/9, 55.6%), and fine motor skills (5/9, 55.6%) after completion of chemotherapy. Most patients improved on indices of verbal memory (7/9, 77.8%), visuospatial learning (6/8, 75%), and verbal fluency (5/9, 55.6%). Despite changes in indices of cognitive function, most patients' perceived quality of life improved (5/9, 55.6%) after chemotherapy. <h3>Conclusions:</h3> Although gynecologic cancer patients complain of CICI, there is discrepancy regarding its incidence and affected cognitive domains. This pilot study highlights attention and mental flexibility as indices of cognitive dysfunction that may be at risk following receipt of chemotherapy in gynecologic cancer patients. Future research may focus on targeted assessment strategies.

Evaluation of an Augmented Reality Application for Learning Neuroanatomy in Psychology.

Neuroanatomy is difficult for psychology students because of spatial visualization and the relationship among brain structures. Some technologies have been implemented to facilitate the learning of anatomy using three-dimensional (3D) visualization of anatomy contents. Augmented reality (AR) is a promising technology in this field. A mobile AR application to provide the visualization of morphological and functional information of the brain was developed. A sample of 67 students of neuropsychology completed tests for visuospatial ability, anatomical knowledge, learning goals, and experience with technologies. Subsequently, they performed a learning activity using one of the visualization methods considered: a 3D method using the AR application and a two-dimensional (2D) method using a textbook to color, followed by questions concerning their satisfaction and knowledge. After using the alternative method, the students expressed their preference. The two methods improved knowledge equally, but the 3D method obtained higher satisfaction scores and was more preferred by students. The 3D method was also more preferred by the students who used this method during the activity. After controlling for the method used in the activity, associations were found between the preference of the 3D method because of its usability and experience with technologies. These results found that the AR application was highly valued by students to learn and was as effective as the textbook for this purpose.

Free testosterone is related to aspects of cognitive function in women with and without polycystic ovary syndrome.

Evidence suggests impairment in aspects of cognitive function in women with polycystic ovary syndrome (PCOS). Direct effects of raised testosterone levels associated with PCOS are a potential mechanism. We aimed to explore the relationship between testosterone levels and cognitive functioning in women. Women with a range of testosterone levels, including women with PCOS, were recruited. Depressive and anxiety symptoms were measured by self-report. Participants underwent a comprehensive battery of cognitive tests assessing psychomotor speed, visuospatial learning and memory, verbal learning and memory, and executive function. Free testosterone serum levels were assessed. All measures were completed at the same time point. Correlation analysis (Spearman's Rho) was used to explore associations between free testosterone and cognitive test variables. Eighty-one women were recruited, with 40 meeting diagnostic criteria for PCOS. Free testosterone was normally distributed, with significant overlap between women with PCOS and controls. Mean depressive and anxiety symptoms were in the mild range. Higher free testosterone levels were significantly correlated with poorer performance on measures assessing psychomotor speed and visuospatial learning. These significant correlations remained after adjusting for confounders (premorbid verbal IQ, depressive, and anxiety symptoms). Higher free testosterone levels in women were associated with poorer cognitive function, specifically psychomotor speed and visuospatial learning. Women with PCOS and raised free testosterone levels may experience impairment in these aspects of cognitive function which are not accounted for by mood or anxiety symptoms.

Investigating the Residual Effects of Chronic Cannabis Use and Abstinence on Verbal and Visuospatial Learning.

Rationale: Regular cannabis users have been shown to differ from non-using controls in learning performance. It is unclear if these differences are specific to distinct domains of learning (verbal, visuospatial), exacerbate with extent of cannabis exposure and dissipate with sustained abstinence.Objective: This study examines different domains of learning (verbal, visuospatial) in current and abstaining cannabis users, and the role of chronicity of use.Methods: In a cross-sectional design, we examined 127 psychiatrically healthy participants (65 female) with mean aged of 34 years. Of these, 69 individuals were current regular cannabis users (mean 15 years use), 12 were former cannabis users abstinent for ~2.5 yrs (after a mean of 16 years use), and 46 were non-cannabis using controls. Groups were compared on verbal learning performance assessed via the California Verbal Learning Test (CVLT-II) and for visuospatial learning measured with the Brown Location Test (BLT). We explored the association between CVLT/BLT performance and cannabis use levels in current and former users.Results: Current cannabis use compared to non-use was associated with worse performance on select aspects of verbal learning (Long Delay Cued Recall) and of visuospatial learning (Retroactive Interference and LD Rotated Recall). Prolonged abstinence was associated with altered verbal learning but intact visuospatial learning. There were non-significant correlations between distinct cannabis use measures, age and learning in both current and former users.Conclusions: Our findings suggest cannabis use status (current use, former use) affects different domains of learning (verbal and visuospatial) in a distinct fashion. These findings might be accounted for in the design of cognitive interventions aimed to support abstinence in cannabis users.

Potentiating Hemorrhage in a Periadolescent Rat Model of Closed-Head Traumatic Brain Injury Worsens Hyperexcitability but Not Behavioral Deficits.

Post-traumatic epilepsy (PTE) and neurocognitive deficits are devastating sequelae of head injuries that are common in adolescents. Investigating desperately needed treatments is hindered by the difficulties in inducing PTE in rodents and the lack of established immature rat models of pediatric PTE. Hemorrhage is a significant risk factor for PTE, but compared to humans, rats are less prone to bleeding because of their rapid blood coagulation system. In this study, we promoted bleeding in the controlled cortical impact (CCI) closed-head injury model with a 20 min pre-impact 600 IU/kg intraperitoneal heparin injection in postnatal day 35 (P35) periadolescent rats, given the preponderance of such injuries in this age group. Temporo-parietal CCI was performed post-heparin (HTBI group) or post-saline (TBI group). Controls were subjected to sham procedures following heparin or saline administration. Continuous long-term EEG monitoring was performed for 3 months post-CCI. Sensorimotor testing, the Morris water maze, and a modified active avoidance test were conducted between P80 and P100. Glial fibrillary acidic protein (GFAP) levels and neuronal damage were also assessed. Compared to TBI rats, HTBI rats had persistently higher EEG spiking and increased hippocampal GFAP levels (p < 0.05). No sensorimotor deficits were detected in any group. Compared to controls, both HTBI and TBI groups had a long-term hippocampal neuronal loss (p < 0.05), as well as contextual and visuospatial learning deficits (p < 0.05). The hippocampal astrogliosis and EEG spiking detected in all rats subjected to our hemorrhage-promoting procedure suggest the emergence of hyperexcitable networks and pave the way to a periadolescent PTE rat model.

Investigation of a Model-Based Working Memory Training With and Without Distractor Inhibition and Its Comparative Efficacy: A Randomized Controlled Trial on Healthy Old Adults.

Background: Various working memory (WM) trainings have been tested, but differences in experimental designs, the lack of theoretical background, and the need of identifying task-related processes such as filtering efficiency limit conclusions about their comparative efficacy.Objectives: In this study, we compared the efficacy of a model-based WM training with (MB+) and without (MB) distractor inhibition on improving WM capacity to a dual n-back and active control condition.Methods: This randomized clinical trial included 123 healthy elderly adults (78 women, 45 men; aged 64.1 ± 8.3 years). All groups underwent 12 40-min training sessions over 3 weeks and four cognitive testing sessions. The first two sessions served as double baseline to account for practice effects. Primary outcome was WM capacity post-training measured by complex span tasks. Near and far transfer was assessed by simple span, n-back, visuospatial and verbal learning, processing speed, and reasoning tasks.Results: Due to preliminary termination (COVID-19), 93 subjects completed the post-training and 60 subjects the follow-up session. On a whole group level, practice effects occurred from prebaseline to baseline in WM capacity (b = 4.85, t(103) = 4.01, p < 0.001, r = 0.37). Linear mixed-effects models revealed a difference in WM capacity post-training between MB+ and MB (b = −9.62, t(82) = −2.52, p = 0.014, r = 0.27) and a trend difference between MB+ and dual n-back (b = −7.59, t(82) = −1.87, p = 0.065, r = 0.20) and control training (b = −7.08, t(82) = −1.86, p = 0.067, r = 0.20). Univariate analyses showed an increase between pre- and post-training for WM capacity within MB+ (t(22) = −3.34, p < 0.05) only. There was no difference between groups pre- and post-training regarding near and far transfer. Univariate analyses showed improved visuospatial learning within MB+ (t(21) = −3.8, p < 0.05), improved processing speed (t(23) = 2.19, p< 0.05) and n-back performance (t(23) = 2.12, p < 0.05) in MB, and improved n-back performance (t(25) = 3.83, p < 0.001) in the dual n-back training.Interpretation: A model-based WM training including filtering efficacy may be a promising approach to increase WM capacity and needs further investigation in randomized controlled studies.

Androgen deprivation therapy and cognitive decline-associations with brain connectomes, endocrine status, and risk genotypes.

Evidence suggests that prostate cancer (PC) patients undergoing androgen deprivation therapy (ADT) are at risk for cognitive decline (CD), but the underlying mechanisms are less clear. In the present study, changes in cognitive performance and structural brain connectomes in PC patients undergoing ADT were assessed, and associations of cognitive changes with endocrine status and risk genotypes were explored. Thirty-seven PC patients underwent cognitive assessment, structural MRI, and provided blood samples prior to ADT and after 6 months of treatment. Twenty-seven age- and education-matched healthy controls (HCs) underwent the same assessments. CD was determined using a standardized regression-based approach and defined as z-scores ≤ -1.64. Changes in brain connectomes were evaluated using graph theory. Associations of CD with testosterone levels and genotypes (APOE, COMT, BDNF) were explored. Compared with HCs, PC patients demonstrated reduced testosterone levels (p < 0.01) and higher rates of decline for 13 out of 15 cognitive outcomes, with three outcomes related to two cognitive domains, i.e., verbal memory and visuospatial learning and memory, reaching statistical significance (p ≤ 0.01-0.04). Testosterone level changes did not predict CD. COMT Met homozygote PC patients evidenced larger reductions in visuospatial memory compared with Val carriers (p = 0.02). No between-group differences were observed in brain connectomes across time, and no effects were found of APOE and BDNF. Our results indicate that PC patients undergoing ADT may evidence CD, and that COMT Met homozygotes may be at increased risk of CD. The results did not reveal changes in brain connectomes or testosterone levels as underlying mechanisms. More research evaluating the role of ADT-related disruption of the dynamics of the hypothalamic-pituitary-gonadal axis is needed.

Variable objective sleep quality is related to worse spatial learning and memory in young adults

ObjectiveThe majority of research on sleep and cognition has focused on mean markers of sleep across multiple nights; however, variable sleep patterns have become increasingly common in the modern era. The purpose of this study was to examine whether objective intraindividual variability in sleep quantity and quality are related to verbal and visuospatial learning and memory functioning in young adults. MethodsA total of 218 young adult college students were recruited from a university in the Eastern United States, among which 187 participants (70.6% female; mean age = 20.5, SD = 1.5) had complete actigraphy and cognitive performance data. Objective intraindividual means and variabilities of sleep quantity (total sleep time) and sleep quality (percent wake after sleep onset) were measured over a 1- to 2-week timeframe using wrist actigraphy. Verbal and visuospatial learning and memory were assessed using the International Shopping List and Groton Maze Learning tests of the Cogstate computerized test battery. ResultsGreater intraindividual variability in actigraphy-derived sleep quality was associated with poorer visuospatial learning and memory performance after controlling for mean sleep quality and visuomotor attention and processing speed (ps < 0.05). Actigraphic measures of sleep quantity were not related to any learning and memory measures. ConclusionIn young adults, intraindividual variability in objective sleep quality was significantly related to visuospatial learning and memory, over and above mean sleep quality. Given these associations, future studies should aim to identify modifiable lifestyle and environmental factors contributing to variable sleep quality.

Learning of spatial configurations of a co-actor's attended objects in joint visual search

Regarding the effects of joint action on visual memory, previous research has focused on the memory of a single object that a participant and their co-actor attended together (i.e., a shared situation), while the literature on memory has demonstrated that spatial regularity composed of multiple objects can also be learned. We aimed to examine whether the visuospatial regularity of the co-actor's attended objects could be strongly encoded. We repeatedly presented the same configuration of two targets and two sets of distractors in different colors (i.e., blue and red) to participants. In Experiment 1, pairs of participants simultaneously searched for the same target in the joint group while individual participants searched for the target alone in the single group. As a result, greater facilitation in reaction time was observed in earlier epochs in the joint group, reinforced by the learning of visuospatial regularity, compared to the single group. Experiment 2 examined whether the co-actor's attended context could be strongly encoded although two persons simultaneously searched for different targets (i.e., parallel situation) such that one searched for the blue target and the other for the red target. The results showed no evidence regarding participants' learning visuospatial regularity of the co-actor's attended objects, indicating that co-actor's learning information cannot be shared in this situation. This study revealed that facilitation of visuospatial learning in joint action would require two individuals to attend to the same objects when they perform the task.

The Brief International Cognitive Assessment in Multiple Sclerosis (BICAMS): Validation in Arabic and Lebanese Normative Values.

Multiple sclerosis (MS) is often associated with cognitive deficits. Accurate evaluation of the MS patients' cognitive performance is essential for diagnosis and treatment recommendation. The Brief International Cognitive Assessment in Multiple Sclerosis (BICAMS), widely used cognitive testing battery, examines processing speed, verbal and visuospatial learning, and memory. Our study aims to examine the psychometric properties of an Arabic version of the BICAMS and to provide normative values in a Lebanese sample. The BICAMS, comprised of the Symbol Digit Modalities Test (SDMT), Brief Visuospatial Memory Test-Revised (BVMT-R), and a newly developed verbal learning/memory test, the Verbal Memory Arabic Test (VMAT), were administered on healthy subjects and MS patients. The sample consisted of 180 healthy individuals, of whom 63 were retested after 2-3 weeks. Forty-three MS patients matched with 43 healthy subjects based on age, sex, and years of education were assessed. A sample of 10 MS patients was also examined on two occasions. Test-retest reliability and criterion-related validity were examined, and regression-based norms were derived. The test-retest correlations showed good evidence of reliability with coefficients ranging between 0.64 and 0.73 in the healthy sample, and between 0.43 and 0.92 in the MS sample. The BICAMS was able to discriminate between MS patients and matched healthy participants on the SDMT and BVMT-R. Normative data were comparable to other studies. This new Arabic version of the BICAMS shows initial good psychometric properties. While good evidence of VMAT's reliability was shown in the healthy participants, less test-retest reliability in this tool was seen in the MS group, and partial criterion-related validity was evident. This renders further examination of the VMAT. We provide regression-based norms for a Lebanese sample and encourage the use of this battery in both research and clinical settings.

Touching digital objects directly on multi-touch devices fosters learning about visual contents

Multi-touch devices are widely used in our daily lives and the field of education. Users touch the digital objects depicted on these devices directly with their hands and fingers. Prior research indicated that information processing is influenced by the proximity of the hand(s) to the displayed information: particularly visuospatial processing is fostered near the hands. Two experiments investigated this effect of hand proximity for learning about visuospatial information on multi-touch devices. Participants either touched digital objects (pictures of paintings with text labels) on a multi-touch table directly (near hand) or manipulated the objects indirectly by touching placeholders of the objects (far hand; hand proximity). In Experiment 2, additionally, the interaction time with the displayed learning materials (time of contact between hands and objects/placeholders) was analyzed as continuous factor (duration of touch). In both experiments, learning outcomes were measured by recognition performance on the visuospatial and verbal aspects of the presented materials. Results of Experiment 1 showed – as expected – that visuospatial learning was fostered near the hands. Experiment 2 replicated this effect for visuospatial learning, when touch durations were sufficiently long. Hand proximity had no influence on verbal learning in both experiments. The results and implications for designing interactive multi-touch interfaces are discussed.

Effects of daily almond consumption for six months on cognitive measures in healthy middle-aged to older adults: a randomized control trial

ABSTRACT Background Age-related cognitive decline is a major public health issue. Almonds are rich in nutrients that benefit cognitive function. Objective To investigate the impact of almonds on cognition in elderly adults. Design In a six-month, single-blinded, randomized-controlled trial, the effects of an almond intervention on cognition in healthy, middle-aged/older adults (50–75 years) was tested. Subjects were assigned to one of three groups: 1.5 oz/d almond (n = 19), 3 oz/d almond (n = 24), or 3.5 oz/d snack (control, matched for macronutrients in 3.0 oz almonds, (n = 17). Serum analyses for tocopherols, oxidative status and inflammation, and cognition were assessed at baseline (M0), three (M3), and six (M6) months. Results At M6, serum alpha-tocopherol concentrations increased by 8% from M0 (p < 0.05) in the 3 oz almond group but did not increase in the other groups. Serum markers of inflammation and oxidative stress were not significantly different throughout the study among the groups. There was no difference in change over time in cognitive tests among the groups. However, there was a significant improvement in visuospatial working memory (p = 0.023), visual memory and learning (p = 0.017), and spatial planning and working memory (p < 0.001) in subjects receiving 3 oz/d almonds at M6, while the snack group showed no improvement. Conclusions Almonds did not significantly improve cognitive function in cognitively intact middle-aged/older adults over six months. However, a significant improvement at M6 in cognitive measures was observed with 3 oz/d almonds. While these results are encouraging, a study of longer duration in subjects at risk for age-related cognitive decline is warranted. Trial registration: ClinicalTrials.gov identifier: NCT03093896.

Test breve de memoria visuoespacial-revisado: normalización y estandarización de la prueba en población española

The brief visuospatial memory test-revised (BVMT-R) assesses visuospatial learning and memory in adults. It has equivalent forms that allow reassessing patients. To obtain normative and standardized data for the BVMT-R taking into account the sociodemographic characteristics of the Spanish population. The present study is part of the Normacog Project. Nine hundred three participants (18 to 93 years old) were assessed using the BVMT-R (form 1). The effect of age, level of education and gender was analyzed on the BVMT-R, and percentiles and scalar scores adjusted by age and level of education were created. A significant effect of age and educational level on the analyzed variables was observed (trial 1; total recall; trial 4; discrimination index), explaining from 12% to 40% of the variance. The older and less educated participants obtained lower performance in all the analyzed variables of the BVMT-R. Gender had not a significant effect in the analyzed variables. The study provides standardized and normalized data for the BVMT-R taking into account the Spanish sociodemographic characteristics. The results confirm the in?uence of age and level of education in the performance of the test, so normative data are provided to correct the BVMT-R taking into account these characteristics.

TDCS over posterior parietal cortex increases cortical excitability but decreases learning: An ERPs and TMS-EEG study

The application of anodal transcranial direct current stimulation (AtDCS) is generally associated with increased neuronal excitability and enhanced cognitive functioning. Nevertheless, previous work showed that applying this straight reasoning does not always lead to the desired results at behavioural level. Here, we investigated electrophysiological markers of AtDCS-mediated effects on visuo-spatial contextual learning (VSCL). In order to assess cortical excitability changes after 3 mA AtDCS applied over posterior parietal cortex, event-related potentials (ERPs) were collected during task performance. Additionally, AtDCS-induced effects on cortical excitability were explored by measuring TMS-evoked potentials (TEPs) collected before AtDCS, after AtDCS and after AtDCS and VSCL interaction. Behavioural results revealed that the application of AtDCS induced a reduction of VSCL. At the electrophysiological level, ERPs showed enhanced cortical response (P2 component) in the group receiving Real-AtDCS as compared to Sham-AtDCS. Cortical responsiveness at rest as measured by TEP, did not indicate any significant difference between Real- and Sham-tDCS groups, albeit a trend was present. Overall, our results suggest that AtDCS increases cortical response to incoming visuo-spatial stimuli, but with no concurrent increase in learning. Detrimental effects on behaviour could result from the interaction between AtDCS- and task-mediated cortical activation. This interaction might enhance cortical excitability and hinder normal task-related neuroplastic phenomena subtending learning.

Mifepristone enhances the neural efficiency of human visuospatial memory encoding and recall

Glucocorticoid receptor (GR) antagonism is a promising new treatment for cognitive dysfunction in psychiatric disorders but the effects of GR antagonism on cognition related brain activity is poorly understood. This study examines the effects of the GR and progesterone receptor antagonist mifepristone on the neural correlates of visuospatial learning and working memory in healthy male participants. The study used a pharmacological functional magnetic resonance imaging (fMRI) design to determine mifepristone effects on visuospatial paired associates learning (vPAL) and n-back working memory (WM) fMRI task related brain activations. 20 right-handed healthy male participants received 600 mg mifepristone or placebo on two separate imaging days and each participant performed fMRI tasks four hours later. The effect of mifepristone on task related brain activations was determined using Region of Interest (ROI) fMRI analyses and an exploratory whole brain voxel-wise fMRI task analyses was also conducted. The vPAL task ROI analysis found that mifepristone administration was significantly associated with decreased fusiform cortex activations in first and second encoding blocks (p = 0.007, p = 0.04) and decreased angular and precuneal cortices activations in the first recall block (p = 0.01, p = 0.02). There were no significant differences in fMRI brain activations associated with mifepristone administration in the n-back task ROI’s (all p > 0.05). Mifepristone administration did not significantly affect fMRI brain activations in the whole brain voxel-wise analyses for both tasks. N-back and vPAL task reaction times and accuracy were similar in both mifepristone and placebo conditions (all p > 0.05). Our finding of decreased fusiform, angular and precuneal vPAL task related brain activity associated with mifepristone administration for the same behavioural performance as found in the placebo condition may represent improved efficiency of visuospatial memory encoding and recall. These findings provide evidence that mifepristone may enhance the efficiency of human visuospatial memory and calls for further studies in patient populations using an fMRI approach to provide proof of concept for new treatments.

People with mesial temporal lobe epilepsy have altered thalamo-occipital brain networks

While temporal lobe epilepsy (TLE) is a focal epilepsy, previous work demonstrates that TLE causes widespread brain-network disruptions. Impaired visuospatial attention and learning in TLE may be related to thalamic arousal nuclei connectivity. Our prior preliminary work in a smaller patient cohort suggests that patients with TLE demonstrate abnormal functional connectivity between central lateral (CL) thalamic nucleus and medial occipital lobe. Others have shown pulvinar connectivity disturbances in TLE, but it is incompletely understood how TLE affects pulvinar subnuclei. Also, the effects of epilepsy surgery on thalamic functional connectivity remains poorly understood. In this study, we examine the effects of TLE on functional connectivity of two key thalamic arousal-nuclei: lateral pulvinar (PuL) and CL. We evaluate resting-state functional connectivity of the PuL and CL in 40 patients with TLE and 40 controls using fMRI. In 25 patients, postoperative images (>1 year) were also compared with preoperative images. Compared to controls, patients with TLE exhibit loss of normal positive connectivity between PuL and lateral occipital lobe (p < 0.05), and a loss of normal negative connectivity between CL and medial occipital lobe (p < 0.01, paired t-tests). FMRI amplitude of low-frequency fluctuation (ALFF) in TLE trended higher in ipsilateral PuL (p = 0.06), but was lower in the lateral occipital (p < 0.01) and medial occipital lobe in patients versus controls (p < 0.05, paired t-tests). More abnormal ALFF in the ipsilateral lateral occipital lobe is associated with worse preoperative performance on Rey Complex Figure Test Immediate (p < 0.05, r = 0.381) and Delayed scores (p < 0.05, r = 0.413, Pearson’s Correlations). After surgery, connectivity between PuL and lateral occipital lobe remains abnormal in patients (p < 0.01), but connectivity between CL and medial occipital lobe improves and is no longer different from control values (p > 0.05, ANOVA, post hoc Fischer’s LSD). In conclusion, thalamic arousal nuclei exhibit abnormal connectivity with occipital lobe in TLE, and some connections may improve after surgery. Studying thalamic arousal centers may help explain distal network disturbances in TLE.