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Traditional cognitive assessment in neurological conditions involving physical disability is often prevented by the presence of verbal-motor impairment; to date, an extensive motor-verbal-free neuropsychological battery is not available for such purposes. We adapted a set of neuropsychological tests, assessing language, attentional abilities, executive functions and social cognition, for eye-tracking (ET) control, and explored its feasibility in a sample of healthy participants. Thirty healthy subjects performed a neuropsychological assessment, using an ET-based neuropsychological battery, together with standard "paper and pencil" cognitive measures for frontal (Frontal Assessment Battery-FAB) and working memory abilities (Digit Sequencing Task) and for global cognitive efficiency (Montreal Cognitive Assessment-MoCA). Psychological measures of anxiety (State-Trait Anxiety Inventory-Y-STAI-Y) and depression (Beck Depression Inventory-BDI) were also collected, and a usability questionnaire was administered. Significant correlations were observed between the "paper and pencil" screening of working memory abilities and the ET-based neuropsychological measures. The ET-based battery also correlated with the MoCA, while poor correlations were observed with the FAB. Usability aspects were found to be influenced by both working memory abilities and psychological components. The ET-based neuropsychological battery developed could provide an extensive assessment of cognitive functions, allowing participants to perform tasks independently from the integrity of motor or verbal channels. Further studies will be aimed at investigating validity and usability components in neurological populations with motor-verbal impairments. [ABSTRACT FROM AUTHOR]

Attention is improved through cognitive rehabilitation. The purpose of the present study was the evaluation of the effect of a paper and pencil program for attention rehabilitation and strengthening (PARS) in children with ADHD. Thirty children with ADHD were randomly divided into two equal intervention and control groups. The intervention group received 12-15 sessions of intervention through PARS. Sustained, selective, and shifting attention, inhibitory control, and working memory were assessed by Persian attention registration, Stroop, color trail making, Go/No-Go, and 1- back tests. Analyses indicated that the experimental group, in comparison with the control group, showed improved selective and sustained attention and the training effects transfers to executive functions, inhibitory control and working memory. The result is discussed in the light of transferability of training effects from attention to executive functions. [ABSTRACT FROM AUTHOR]

Background: The model of executive attention proposes that temporal organization, i.e., the time necessary to bring novel tasks to fruition is an important construct that modulates executive control. Subordinate to temporal organization are the constructs of working memory, preparatory set, and inhibitory control.Objective: The current research operationally-defined the constructs underlying the theory of executive attention using intra-component latencies (i.e., reaction times) from a 5-span backward digit test from patients with suspected mild cognitive impairment (MCI).Methods: An iPad-version of the Backward Digit Span Test (BDT) was administered to memory clinic patients. Patients with (n = 22) and without (n = 36) MCI were classified. Outcome variables included intra-component latencies for all correct 5-span serial order responses.Results: Average total time did not differ. A significant 2-group by 5-serial order latency interaction revealed the existence of distinct time epochs. Non-MCI patients produced slower latencies on initial (position 2-working memory/preparatory set) and latter (position 4-inhibitory control) correct serial order responses. By contrast, patients with MCI produced a slower latency for middle serial order responses (i.e., position 3-preparatory set). No group differences were obtained for incorrect 5-span test trials.Conclusion: The analysis of 5-span BDT serial order latencies found distinct epochs regarding how time was allocated in the context of successful test performance. Intra-component latencies obtained from tests assessing mental re-ordering may constitute useful neurocognitive biomarkers for emergent neurodegenerative illness. [ABSTRACT FROM AUTHOR]

The differences in the executive attention network and the related blood oxygen characteristics of the right frontal-parietal network brain area between athletes from interceptive and strategic sport were investigated. Strategic athletes had higher accuracy and longer reaction time (RT) compared with interceptive sports athletes, lower flanker conflict effects on accuracy compared to the other two group. It was accompanied by significant activation of the rdLPFC and the rIFG. Strategic athletes had higher flanker conflict effects on RT compared with interception athletes under the invalid cue condition, which was accompanied by significant activation of the right IFG. The strategic athletes complete the task under the condition of invalid clues indicating top-down control, and which is closely related to the activation of the right frontal-parietal network. [ABSTRACT FROM AUTHOR]

Background: In older people with cognitive impairment (CI), executive function (EF) has been associated with motor performance including balance and gait. The literature examining and supporting a relationship between balance performance and other cognitive domains is limited.Objective: To investigate the relationship between global cognition and cognitive domain function and balance performance in older people with CI.Methods: The iFOCIS randomized controlled trial recruited 309 community-dwelling older people with CI. Baseline assessments completed before randomization were used for analyses including the Addenbrooke's Cognitive Examination-III (ACE-III; global cognition) and its individual cognitive domains (attention; memory; verbal fluency; language; visuospatial ability) and the Frontal Assessment Battery (FAB), a measure of EF. A composite balance score was derived from postural sway and leaning balance tests.Results: In linear regression analyses adjusted for covariates, global cognition and each cognitive domain were significantly associated with balance performance. EF (verbal fluency; β= -0.254, p < 0.001, adjusted R2 = 0.387) and visuospatial ability (β= -0.258, p < 0.001, adjusted R2 = 0.391) had the strongest associations with balance performance. In a comprehensively adjusted multivariable model including all of the ACE-III cognitive domains, visuospatial ability and EF (verbal fluency) were independently and significantly associated with balance performance.Conclusion: Poorer global cognition and cognitive domain function were associated with poorer balance performance in this sample of people with CI. Visuospatial ability and EF were independently associated with balance, highlighting potential shared neural networks and the role higher-level cognitive processes and spatial perception/processing play in postural control. [ABSTRACT FROM AUTHOR]

Objective: We examined whether children with attention-deficit/hyperactivity disorder (ADHD) differ from children without ADHD in attention, executive functions, and motor skills and whether measures of parents' perceptions and children's performance reveal comparable results. Method: About 52 children with ADHD and 52 children without ADHD aged 6 to 13 years completed performance-based measures of attention, executive functions, and motor skills. Parents completed questionnaires to rate their children's skills. Results: Parent questionnaires but not performance-based measures revealed higher inattention and lower executive function skills in children with ADHD compared to controls. For motor skills, both measurement methods revealed lower mean values and a higher number of children showing an impairment in the ADHD group. Parent-reported difficulties but not performance-based measures were related to the presence of an ADHD diagnosis. Conclusion: Our findings suggest that considering both parent questionnaires and performance-based measures will lead to a comprehensive picture of a child's strengths and difficulties. [ABSTRACT FROM AUTHOR]

This study utilized data from the Avon Longitudinal Study of Parents and Children (N = 14,860) to examine whether early-life family income (age 0-5) predicted long-term academic achievement (age 16-18) and to investigate the role of executive function (EF) assessed multiple times across age 7-11 in explaining this association. Task-based EF was a significant mediator between early-life family income and later academic achievement in every model. This mediating pathway persisted when adjusting for a comprehensive panel of covariates including verbal IQ, sex, family income at ages 8 and 18, and early-life temperament. Additionally, teacher-rated and parent-rated EF mediated in some models. Overall, these findings suggest that childhood EF may play an important role in perpetuating income-based educational disparities. [ABSTRACT FROM AUTHOR]

Background: Subarachnoid hemorrhage (SAH) is a devastating disease associated with high mortality and morbidity. Besides neurological sequelae, neuropsychological deficits largely contribute to patients' long-term quality of life. Little is known about the pituitary gland volume (PGV) after SAH compared to healthy referents and the association of PGV with long-term outcome including cognitive function.Methods: Sixty consecutive non-traumatic SAH patients admitted to the neurological intensive care unit between 2010 and 2014 were enrolled. 3-Tesla magnetic resonance imagining was performed at baseline (16 days) and 12 months after SAH to measure PGV semi-automatically using the software iPlan Net 3.5.0. PGV was compared to age and sex matched healthy referents. The difference between baseline and 1-year-PGV was classified as increase (> 20 mm3 PGV increase), stable (± 20 mm3), or decrease (> 20 mm3 PGV decrease). In addition, total intracerebral volume was calculated. Neuropsychological testing was applied in 43 SAH patients at 1-year follow up encompassing several domains (executive, attention, memory) and self-assessment (questionnaire for self-perceived deficits in attention [German: FEDA]) of distractibility in mental processes, fatigue and decrease in motivation. Multivariable regression with multivariable generalized linear models was used for comparison of PGVs and for subgroup analysis to evaluate a potential association between PGV and neuropsychological outcome.Results: Patients were 53 years old (IQR = 44-63) and presented with a median Hunt&Hess grade of 2 (IQR = 1-3). SAH patients had a significantly lower PGV both at baseline (360 ± 19 mm3, p < 0.001) and 1 year (367 ± 18 mm3p < 0.001) as compared to matched referents (mean 505 ± 18 mm3). PGV decreased by 75 ± 8 mm3 in 28 patients, increased by 120 ± 22 mm3 in 22 patients and remained stable in 10 patients at 1-year follow-up. PGV in patients with PGV increase at 12 months was not different to healthy referents (p = 0.062). Low baseline PGV was associated with impaired executive functions at 1 year (adjOR = 8.81, 95%-CI = 1.46-53.10, p = 0.018) and PGV decrease within 1 year was associated with self-perceived worse motivation (FEDA; Wald-statistic = 6.6, df = 1, p = 0.010).Conclusions: Our data indicate significantly lower PGVs following SAH. The association of sustained PGV decrease with impaired neuropsychological long-term outcome warrants further investigations including neuroendocrine hormone measurements. [ABSTRACT FROM AUTHOR]

Human performance in complex multiple-task environments depends critically on the interplay between cognitive control and cognitive capacity. In this paper we propose a tractable computational model of how cognitive control and capacity influence the speed and accuracy of decisions made in the event-based prospective memory (PM) paradigm, and in doing so test a new quantitative formulation that measures two distinct components of cognitive capacity (gain and focus) that apply generally to choices among two or more options. Consistent with prior work, individuals used proactive control (increased ongoing task thresholds under PM load) and reactive control (inhibited ongoing task accumulation rates to PM items) to support PM performance. Individuals used cognitive gain to increase the amount of resources allocated to the ongoing task under time pressure and PM load. However, when demands exceeded the capacity limit, resources were reallocated (shared) between ongoing task and PM processes. Extending previous work, individuals used cognitive focus to control the quality of processing for the ongoing and PM tasks based on the particular demand and payoff structure of the environment (e.g., higher focus for higher priority tasks; lower focus under high time pressure and with PM load). Our model provides the first detailed quantitative understanding of cognitive gain and focus as they apply to evidence accumulation models, which - along with cognitive control mechanisms - support decision-making in complex multiple-task environments. [ABSTRACT FROM AUTHOR]

Objective: To compare the effects of different surgical approaches for selective amygdalohippocampectomy in patients with pharmacoresistant mesial temporal lobe epilepsy with regard to the neuropsychological outcome and to replicate an earlier study employing a matched-pair design.Method: 47 patients were randomised to subtemporal versus transsylvian approaches. Memory, language, attentional and executive functions were assessed before and 1 year after surgery. Multivariate analyses of variance (MANOVAs) with presurgical and postsurgical assessments as within-subject variables and approach and side of surgery as between-subject factors were calculated. Additionally, the frequencies of individual performance changes based on reliable change indices were analysed.Results: Seizure freedom International League Against Epilepsy (ILAE) 1a, was achieved in 62% of all patients without group difference. MANOVAs revealed no significant effects of approach on cognition. Tested separately for each parameter, verbal recognition memory declined irrespective of approach. Post hoc tests revealed that on group level, the subtemporal approach was associated with a worse outcome for verbal learning and delayed free recall as well as for semantic fluency. Accordingly, on individual level, more patients in the subtemporal group declined in verbal learning. Left side of surgery was associated with decline in naming regardless of approach.Conclusion: The main analysis did not confirm the effects of approach on memory outcome seen in our previous study. Post hoc testing, however, showed greater memory losses with the subtemporal approach. Previous findings were replicated for semantic fluency. The discrepant results are discussed on the background of the different study designs. [ABSTRACT FROM AUTHOR]

Subjective memory complaints (SMC) may represent the preclinical phase of mild cognitive impairment (MCI) due to Alzheimer's disease. Dementia/MCI have been described with a high prevalence in Parkinson's disease (PD), but whether SMC may predict the development of cognitive impairment has been barely explored. To evaluate the frequency and clinical correlates of isolated SMC (PD-SMC) or within the construct of MCI in subjects with PD, 147 PD patients from the PArkinson's disease COgnitive impairment Study (PACOS) were consecutively recruited for the study. This is a multicenter study involving two Movement Disorder Centers in south Italy. All subjects underwent comprehensive neuropsychological evaluation and PD-MCI was diagnosed according to Litvan's criteria. The Memory Assessment Clinics Questionnaire was used to assess SMC. Logistic regression analysis, adjusted for demographics and significant covariates, was used to evaluate clinical differences between groups. Forty-two (28.6%) individuals presented with PD without SMC and/or MCI (PDw), 40 (27,2%) with PD-SMC, 48 (32,6%) PD-SMC-MCI, and 17 (11,6%) PD-MCI without SMC (PD-MCI). When compared to PDw, PD-SMC was significantly associated with anxiety (OR = 3.93, 95% CI = 1.18-13.03), while PD-SMC-MCI related to motor progression (OR = 5.29, 95% CI = 1.12-24.86), and instrumental disability (OR = 6.98, 95% CI = 2.08-23.38). About 60% of patients showed SMC, in isolation or within the MCI frame. The role of SMC in PD seems to have a different etiology depending on the presence/absence of MCI. In particular, PD-SMC would represent a subjective reaction to the disease, while PD-SMC-MCI would depict motor progression and disability. [ABSTRACT FROM AUTHOR]

Background: Persons with chronic pain often report problems with cognitive abilities, such as memory or attention. There is limited understanding of whether objective performance is consistent with subjective reports, and how psychological factors contribute. We aimed to investigate these relationships in a group of patients expressing cognitive concerns, and evaluate the utility of self-report tools for pain management settings.Method: Participants with chronic pain (n = 41) completed standardized neuropsychological tests, and self-report measures of cognitive functioning, pain, mood and sleep, as part of a broader study investigating cognitive performance in pain.Results: Average neuropsychological test performance was subtly below normative means (within one standard deviation). Twenty-five percent of the sample scored substantially below age-adjusted norms on one or more objective tests. There were moderate-to-large associations between objective performance (e.g. Trail-Making B) and subjective cognitive complaints (e.g. Everyday Memory Questionnaire - Revised), controlling for age and education level. This was moderated by anxiety, such that subjective-objective relationships were particularly strong in those with higher anxiety. Poorer test performance was associated with higher pain intensity and catastrophizing. Subjective-objective cognition relationships remained after controlling for catastrophizing.Conclusion: Patients' self-reported cognitive concerns concurred with objectively measured performance, independent of age, education and catastrophizing. Moreover, those with severe anxiety were more accurate in predicting their cognitive performance. The findings highlight some interesting cognition-mood relationships, and suggest that easy-to-administer questionnaires, such as the Everyday Memory Questionnaire - Revised and the Behavior Rating Inventory of Executive Function - Adult Version, may be useful to capture cognitive concerns in clinical settings.Significance: Cognitive concerns in chronic pain reflected objective neurocognitive performance. This was moderated by anxiety, such that self-reported cognition was more consistent with objective performance in those with high anxiety. Our findings suggest that reported cognitive concerns should be heeded, and self-report measures may be used clinically to facilitate dialogue about cognitive functioning. [ABSTRACT FROM AUTHOR]

Objective: Functional connectivity is known to increase as well as decrease throughout the brain in multiple sclerosis (MS), which could represent different stages of the disease. In addition, functional connectivity changes could follow the atrophy pattern observed with disease progression, that is, moving from the deep grey matter towards the cortex. This study investigated when and where connectivity changes develop and explored their clinical and cognitive relevance across different MS stages.Methods: A cohort of 121 patients with early relapsing-remitting MS (RRMS), 122 with late RRMS and 53 with secondary progressive MS (SPMS) as well as 96 healthy controls underwent MRI and neuropsychological testing. Functional connectivity changes were investigated for (1) within deep grey matter connectivity, (2) connectivity between the deep grey matter and cortex and (3) within-cortex connectivity. A post hoc regional analysis was performed to identify which regions were driving the connectivity changes.Results: Patients with late RRMS and SPMS showed increased connectivity of the deep grey matter, especially of the putamen and palladium, with other deep grey matter structures and with the cortex. Within-cortex connectivity was decreased, especially for temporal, occipital and frontal regions, but only in SPMS relative to early RRMS. Deep grey matter connectivity alterations were related to cognition and disability, whereas within-cortex connectivity was only related to disability.Conclusion: Increased connectivity of the deep grey matter became apparent in late RRMS and further increased in SPMS. The additive effect of cortical network degeneration, which was only seen in SPMS, may explain the sudden clinical deterioration characteristic to this phase of the disease. [ABSTRACT FROM AUTHOR]

Background: Stroke is one of the most common causes of acquired disability, leaving numerous adults with cognitive and motor impairments, and affecting patients' capability to live independently. There is substancial evidence on post-stroke cognitive rehabilitation benefits, but its implementation is generally limited by the use of paper-and-pencil methods, insufficient personalization, and suboptimal intensity. Virtual reality tools have shown potential for improving cognitive rehabilitation by supporting carefully personalized, ecologically valid tasks through accessible technologies. Notwithstanding important progress in VR-based cognitive rehabilitation systems, specially with Activities of Daily Living (ADL's) simulations, there is still a need of more clinical trials for its validation. In this work we present a one-month randomized controlled trial with 18 stroke in and outpatients from two rehabilitation units: 9 performing a VR-based intervention and 9 performing conventional rehabilitation.Methods: The VR-based intervention involved a virtual simulation of a city - Reh@City - where memory, attention, visuo-spatial abilities and executive functions tasks are integrated in the performance of several daily routines. The intervention had levels of difficulty progression through a method of fading cues. There was a pre and post-intervention assessment in both groups with the Addenbrooke Cognitive Examination (primary outcome) and the Trail Making Test A and B, Picture Arrangement from WAIS III and Stroke Impact Scale 3.0 (secondary outcomes).Results: A within groups analysis revealed significant improvements in global cognitive functioning, attention, memory, visuo-spatial abilities, executive functions, emotion and overall recovery in the VR group. The control group only improved in self-reported memory and social participation. A between groups analysis, showed significantly greater improvements in global cognitive functioning, attention and executive functions when comparing VR to conventional therapy.Conclusions: Our results suggest that cognitive rehabilitation through the Reh@City, an ecologically valid VR system for the training of ADL's, has more impact than conventional methods.Trial Registration: This trial was not registered because it is a small sample study that evaluates the clinical validity of a prototype virtual reality system. [ABSTRACT FROM AUTHOR]

There is a need for validated measures of attention for use in longitudinal studies of older populations. We studied 249 participants aged 80 to 101 years using the population-based MOBILIZE Boston Study. Four subscales of the Test of Everyday Attention (TEA) were included, measuring attention switching, selective, sustained and divided attention and a neuropsychological battery including validated measures of multiple cognitive domains measuring attention, executive function and memory. The TEA previously has not been validated in persons aged 80 and older. Among participants who completed the TEA, scores on other attentional measures strongly with TEA domains (R=.60-.70). Proportions of participants with incomplete TEA subscales ranged from 8% (selective attention) to 19% (attentional switching). Reasons for not completing TEA tests included failure to comprehend test instructions despite repetition and practice. These results demonstrate the challenges and potential value of the Test of Everyday Attention in studies of very old populations. [ABSTRACT FROM AUTHOR]

Background: Levels of sitting among adolescents are high, especially during the school day. The acute cognitive and health consequences associated with prolonged sitting are poorly understood in adolescents. This randomized crossover design study examined the acute effects of a simulated school day with reduced sitting or usual sitting on adolescents' cognitive function and cardiometabolic biomarkers.Methods: Eighteen healthy school aged adolescents were recruited from the community to the study (11 males; 7 females; mean age [SD] = 13.5 ± 0.9 years). Two protocols were developed to simulate an adolescent school day, the amount of time spent sitting was manipulated reflecting: a 'typical' day (65% of the time spent sitting with two sitting bouts sitting >20 min) and a 'reduced sitting' day (adolescents sat for 50% less time with no bouts of sitting >20 mins). The order that participants were exposed to each condition was randomized (via random number generator). Participants were not fully blinded as they could observe the difference between conditions. Energy intake and moderate to vigorous physical activity (MVPA) were standardized for both conditions and monitored for 48 h post-condition for compensatory effects. Cognitive (working memory) and cardiometabolic outcomes (lipids, glucose, insulin, IL-6, apo-A1, apo-B, blood pressure,) were assessed pre and post for both conditions, BMI and body fat were assessed on the morning of the intervention. Data were analyzed using linear mixed models. Standardised effect sizes were calculated.Results: Compared with the typical school day, the reduced sitting day demonstrated significant positive effects for apoB/apoA-1 ratio (adjusted difference ± SD) -0.02 ± 0.03; P = 0.03; effect size [Cohen's d] = -0.67. Findings for total cholesterol -0.19 ± 0.27; P = 0.28; d = -0.71; HDL cholesterol -0.23 ± 0.50; P = 0.12 d = -0.66; and total cholesterol/HDL ratio 0.25 ± 0.53; P = 0.25; d = 0.51 and for cognition 0.64 ± 0.15; P = 0.15; d = 0.54 were non-significant. There were no compensatory changes in participant energy expenditure or energy intake for 48 h post intervention.Conclusion: Reducing school day sitting time in adolescents' resulted in significant improvements in apoB/apoA-1 ratio with medium effect sizes for total cholesterol, HDL cholesterol and total cholesterol/HDL ratio. Cognitive function results showed the equivalent of a 6 month improvement in effective mental-attentional capacity.Trial Registration: The trial was registered as a clinical trial with the Australian and New Zealand Clinical Trials Registry ( ACTRN12614001064695 ) on the 3rd of October 2014 - registered retrospectively. [ABSTRACT FROM AUTHOR]

While data are accumulating on the association between neuropsychological performance and real-world endpoints, less is known about the association with medical self-management skills. The self-management of type 1 diabetes (T1D) is often complex, and mismanagement can result in hypoglycaemia and hyperglycaemia and associated morbidity and mortality. The T1D Exchange conducted a case-control study evaluating factors associated with severe hypoglycaemia in older adults (≥ 60 years old) with longstanding T1D (≥ 20 years). A battery of neuropsychological and functional assessments was administered, including measures of diabetes-specific self-management skill (diabetes numeracy) and instrumental activities of daily living (IADL). After adjusting for confounding variables, diabetes numeracy was related to memory and complex speeded attention; while IADL were associated with simple processing speed, executive functioning, complex speeded attention and dominant hand dexterity. The severity of overall cognitive deficit was uniquely associated with both diabetes numeracy and IADL, when controlling for age, education, frailty and depression. This study demonstrates that the cognitive deficits in older adults with T1D have functional implications for both diabetes management and IADL. Further research is needed to determine specific interventions to maximise diabetes self-management in older adults with declining cognition. [ABSTRACT FROM PUBLISHER]

Purpose: Neurocognitive impairment is frequently observed among acute lymphoblastic leukemia (ALL) survivors within the domains of intelligence, attention, processing speed, working memory, learning, and memory. However, few have investigated treatment-induced changes in neurocognitive function during the first months of treatment. Additionally, dysfunction during treatment may be preceded by changes in biomarkers measured within cerebrospinal fluid (CSF). Identification of acute declines in neurocognitive function, as well as predictive genotypes or biomarkers, could guide therapeutic trials of protective interventions.Methods: This study collects CSF while prospectively assessing neurocognitive functioning (working memory, executive function, learning, processing speed, and attention) of ALL patients using the Cogstate computerized battery at six time points during and after the 2 years of leukemia treatment on a Dana-Farber Cancer Institute ALL Consortium trial.Results: Baseline data collected during the first 3 weeks of induction chemotherapy indicate reliable data as all subjects (N = 34) completed Cogstate baseline testing, while completion and performance checks indicate that 100 % of subjects completed testing and complied with test requirements. The majority (85 %) exhibited normal function compared with age peers. Preliminary analysis of CSF biomarkers (folate, homocysteine, 8-isoprostane, and myelin basic protein) similarly reveals values at baseline within expected normal ranges.Conclusions: The first month of induction therapy for ALL is a reliable baseline for detecting treatment-induced changes in neurocognitive functioning. Consequently, serial data collection might identify subgroups of ALL patients at increased risk for neurocognitive decline, warranting proactive interventions to improve their level of functioning both during treatment and into survivorship. [ABSTRACT FROM AUTHOR]

Background: It is uncertain whether switching to frequent nocturnal hemodialysis improves cognitive function in well-dialyzed patients and how this compares to patients who receive a kidney transplant.Methods: We conducted a multicenter observational study with longitudinal follow-up of the effect on cognitive performance of switching dialysis treatment modality from conventional thrice-weekly hemodialysis to frequent nocturnal hemodialysis, a functioning renal transplant or remaining on thrice-weekly conventional hemodialysis. Neuropsychological tests of memory, attention, psychomotor processing speed, executive function and fluency as well as measures of solute clearance were performed at baseline and again after switching modality. The change in cognitive performance measured by neuropsychological tests assessing multiple cognitive domains at baseline, 4 and 12 months after switching dialysis modality were analyzed using a linear mixed model.Results: Seventy-seven patients were enrolled; 21 of these 77 patients were recruited from the randomized Frequent Hemodialysis Network (FHN) Nocturnal Trial. Of these, 18 patients started frequent nocturnal hemodialysis, 28 patients received a kidney transplant and 31 patients remained on conventional thrice-weekly hemodialysis. Forty-eight patients (62 %) returned for the 12-month follow-up. Despite a significant improvement in solute clearance, 12 months treatment with frequent nocturnal hemodialysis was not associated with substantial improvement in cognitive performance. By contrast, renal transplantation, which led to near normalization of solute clearance was associated with clinically relevant and significant improvements in verbal learning and memory with a trend towards improvements in psychomotor processing speed. Cognitive performance in patients on conventional hemodialysis remained stable with the exception of an improvement in psychomotor processing speed and a decline in verbal fluency.Conclusions: In patients on conventional thrice-weekly hemodialysis, receiving a functioning renal transplant was associated with improvement in auditory-verbal memory and psychomotor processing speed, which was not observed after 12 months of frequent nocturnal hemodialysis. [ABSTRACT FROM AUTHOR]