Patients with Parkinson's Disease may be eligible for Deep Brain Stimulation (DBS) in case of severe motor complications. This thesis provides indications for improving patient selection for DBS,... Show morePatients with Parkinson's Disease may be eligible for Deep Brain Stimulation (DBS) in case of severe motor complications. This thesis provides indications for improving patient selection for DBS, as well as describing new biomarkers based on Electroencephalography (EEG) to aid during the DBS selection process. Show less
Buhrmann, A.; Brands, A.M.A.; Grond, J. van der; Schilder, C.; Mast, R.C. van der; Ottenheim, N.R.; ... ; Berg, E. van den 2020
The cerebellum is increasingly recognised for its role in modulation of cognition, behaviour, and affect. The present study examined the relation between structural cerebellar damage (grey matter... Show moreThe cerebellum is increasingly recognised for its role in modulation of cognition, behaviour, and affect. The present study examined the relation between structural cerebellar damage (grey matter volume (GMV), white matter hyperintensities (WMHs), lacunar infarcts (LIs) and microbleeds (MBs)) and measures of cognitive, psychological (i.e. symptoms of depression and apathy) and general daily functioning in a population of community-dwelling older persons with mild cognitive deficits, but without dementia. In 194 participants of the Discontinuation of Antihypertensive Treatment in Elderly People (DANTE) Study Leiden, the association between cerebellar GMV, WMHs, LIs and MBs and measures of cognitive, psychological and general daily functioning was analysed with linear regression analysis, adjusted for age, sex, education and cerebral volume. Cerebellar GMV was associated with the overall cognition score (standardised beta 0.20 [95% CI, 0.06-0.33]). Specifically, posterior cerebellar GMV was associated with executive function (standardised beta 0.18 [95% CI, 0.03-0.16]). No relation was found between vascular pathology and cognition. Also, no consistent associations were found on the cerebellar GMV and vascular pathology measures and psychological and general daily functioning. In this population of community-dwelling elderly, less posterior cerebellar GMV but not vascular pathology was associated with worse cognitive function, specifically with poorer executive function. No relation was found between cerebellar pathology and psychological and general daily functioning. Show less
Haverkamp, B.F.; Wiersma, R.; Vertessen, K.; Ewijk, H. van; Oosterlaan, J.; Hartman, E. 2020
The aim was to provide a meta-analysis of studies investigating the effects of physical activity interventions on cognitive outcomes and academic performance in adolescents or young adults. A... Show moreThe aim was to provide a meta-analysis of studies investigating the effects of physical activity interventions on cognitive outcomes and academic performance in adolescents or young adults. A systematic review with meta-analysis was performed using the following databases: Embase, ERIC, MEDLINE, PsycINFO and Web of Science. Studies had to meet the following criteria: controlled study design, investigating the effects of physical activity interventions on cognitive outcomes and academic performance in healthy adolescents or young adults (12-30 years). Results showed that acute interventions (n=44) significantly improved processing speed (ES=0.39), attention (ES=0.34) and, inhibition (ES=0.32). In a subsequent meta-regression, shorter duration of intervention was significantly associated with greater improvements in attention (beta=-0.02) and cognitive flexibility (beta=-0.04), whereas age, percentage of boys, intensity and dose were not. Chronic interventions (n=27) significantly improved processing speed (ES=0.30), attention (ES=0.50), cognitive flexibility (ES=0.19), working memory (ES=0.59) and language skills (ES=0.31). In the meta-regression, higher percentage of boys was significantly associated with greater improvements in attention (beta=0.02) and working memory (beta=0.01) whereas age, duration, frequency, dose and load were not. In conclusion, acute and chronic physical activity interventions might be a promising way to improve several cognitive outcomes and language skills in adolescents and young adults. Show less
Duchenne muscular dystrophy is a multifactorial disease including a cognitive phenotype. It is caused by mutations in the X-chromosomal DMD gene from which dystrophin is synthesized. Multiple... Show moreDuchenne muscular dystrophy is a multifactorial disease including a cognitive phenotype. It is caused by mutations in the X-chromosomal DMD gene from which dystrophin is synthesized. Multiple isoforms of dystrophin have been identified. The full length dystrophin isoform Dp427 m is expressed predominantly in muscle. Other isoforms include: Dp427(c), Dp427(p), Dp260, Dp140, Dp116, Dp71 and Dp40. The majority of these isoforms are expressed in brain and several hypotheses exist on their role in subtypes of neurons and astrocytes. However, their function in relation to cognition remains unclear. Unlike progressive muscle wasting, cognitive involvement is not seen in all DMD patients and the severity varies greatly. To achieve a better understanding of brain involvement in DMD, a multidisciplinary approach is required. Here, we review the latest findings on dystrophin isoform expression in the brain; specific DMD-associated learning and behavioural difficulties; and imaging and spectroscopy findings relating to brain structure, networks, perfusion and metabolism. The main challenge lies in determining links between these different findings. If we can determine which factors play a role in the differentiation between severe and minor cognitive problems in DMD in the near future, we can both provide better advise for the patients and also develop targeted therapeutic interventions. (C) 2020 The Author(s). Published by Elsevier B.V. Show less
There is a lack of reliable, repeatable, and non-invasive clinical endpoints when investigating treatments for intellectual disability (ID). The aim of this study is to explore a novel approach... Show moreThere is a lack of reliable, repeatable, and non-invasive clinical endpoints when investigating treatments for intellectual disability (ID). The aim of this study is to explore a novel approach towards developing new endpoints for neurodevelopmental disorders, in this case for ARID1B-related ID. In this study, twelve subjects with ARID1B-related ID and twelve age-matched controls were included in this observational case-control study. Subjects performed a battery of non-invasive neurobehavioral and neurophysiological assessments on two study days. Test domains included cognition, executive functioning, and eye tracking. Furthermore, several electrophysiological assessments were performed. Subjects wore a smartwatch (Withings (R) Steel HR) for 6 days. Tests were systematically assessed regarding tolerability, variability, repeatability, difference with control group, and correlation with traditional endpoints. Animal fluency, adaptive tracking, body sway, and smooth pursuit eye movements were assessed as fit-for-purpose regarding all criteria, while physical activity, heart rate, and sleep parameters show promise as well. The event-related potential waveform of the passive oddball and visual evoked potential tasks showed discriminatory ability, but EEG assessments were perceived as extremely burdensome. This approach successfully identified fit-for-purpose candidate endpoints for ARID1B-related ID and possibly for other neurodevelopmental disorders. Next, results could be replicated in different ID populations or the assessments could be included as exploratory endpoint in interventional trials in ARID1B-related ID. Show less
Dirven, L.; Luerding, R.; Beier, D.; Bumes, E.; Reinert, C.; Seidel, C.; ... ; Hau, P. 2020
Background Combined radiochemotherapy followed by maintenance chemotherapy with cisplatin, lomustine and vincristine within the NOA-07 study resulted in considerable short-term toxicity in adult... Show moreBackground Combined radiochemotherapy followed by maintenance chemotherapy with cisplatin, lomustine and vincristine within the NOA-07 study resulted in considerable short-term toxicity in adult medulloblastoma patients. Here we investigated the long-term impact of this treatment, focusing on neurocognitive functioning and health-related quality of life (HRQoL). Methods Neurocognitive functioning and HRQoL scores over time were determined, and differences between the post-treatment and follow-up assessments were calculated up to 18 months for neurocognition and 60 months for HRQoL. Results 28/30 patients were analyzed. The three preselected HRQoL scales (role, social and cognitive functioning) showed improved scores, to a clinically relevant extent (>= 10 points), compared to post-treatment levels up to 30 months, but decreased afterwards. Z-scores for verbal working memory were worse during follow-up compared to post-treatment scores and remained impaired during 18 months follow-up (i.e. z-score below - 1 standard deviation). Attention was impaired post-treatment, and remained impaired to a clinically relevant extent during follow-up. Coordination/processing speed and lexical verbal fluency improved compared to post-treatment scores, and remained within the normal range thereafter. Other tests of verbal fluency were stable over time, with z-scores within the normal range. Conclusions This long-term follow-up study showed that the NOA-07 treatment regimen was not associated with a deterioration in HRQoL in the post-treatment period. Verbal working memory deteriorated, while other neurocognitive domains did not seem to be impacted negatively by the treatment. Show less
Ellis, N.; Tee, A.; McAllister, B.; Massey, T.; McLauchlan, D.; Stone, T.; ... ; Holmans, P. 2020
BACKGROUND: Huntington's disease (HD) is an inherited neurodegenerative disorder caused by an expanded CAG repeat in the HTT gene. It is diagnosed following a standardized examination of motor... Show moreBACKGROUND: Huntington's disease (HD) is an inherited neurodegenerative disorder caused by an expanded CAG repeat in the HTT gene. It is diagnosed following a standardized examination of motor control and often presents with cognitive decline and psychiatric symptoms. Recent studies have detected genetic loci modifying the age at onset of motor symptoms in HD, but genetic factors influencing cognitive and psychiatric presentations are unknown.METHODS: We tested the hypothesis that psychiatric and cognitive symptoms in HD are influenced by the same common genetic variation as in the general population by 1) constructing polygenic risk scores from large genome-wide association studies of psychiatric and neurodegenerative disorders and of intelligence and 2) testing for correlation with the presence of psychiatric and cognitive symptoms in a large sample (n = 5160) of patients with HD.RESULTS: Polygenic risk score for major depression was associated specifically with increased risk of depression in HD, as was schizophrenia risk score with psychosis and irritability. Cognitive impairment and apathy were associated with reduced polygenic risk score for intelligence.CONCLUSIONS: Polygenic risk scores for psychiatric disorders, particularly depression and schizophrenia, are associated with increased risk of the corresponding psychiatric symptoms in HD, suggesting a common genetic liability. However, the genetic liability to cognitive impairment and apathy appears to be distinct from other psychiatric symptoms in HD. No associations were observed between HD symptoms and risk scores for other neurodegenerative disorders. These data provide a rationale for treatments effective in depression and schizophrenia to be used to treat depression and psychotic symptoms in HD. Show less
Since Antiquity, “active cognition” has been a problematic notion in Aristotelian scholarship. Part of the problem is the definition of what counts as “active”. In the first part of this paper I... Show moreSince Antiquity, “active cognition” has been a problematic notion in Aristotelian scholarship. Part of the problem is the definition of what counts as “active”. In the first part of this paper I shall offer a short survey on various contenders for “active” perceptual cognition defended in recent interpretations of Aristotle, by way of introduction to the more complicated problems of “active” intellectual cognition. In the second part of the paper I will offer—in outline—my interpretation of Aristotle’s theory of intellectual cognition, which takes the most recent findings in the area of perceptual cognition as a starting point. Here I pursue the analogy that Aristotle sets up between perception and intellection throughout the De anima. In the third part of the paper I shall examine a number of influential accounts of active intellectual cognition found in the corpus of Alexander of Aphrodisias, in particular Mantissa 2–5 (also known as De intellectu). These accounts each develop the analogies offered in Aristotle’s De anima III.5 in their own way. Show less
Neurocognitive deficits are frequently described in Duchenne muscular dystrophy (DMD), but it is unknown how these progress over time. Our aim was to longitudinally assess verbal span capacity and... Show moreNeurocognitive deficits are frequently described in Duchenne muscular dystrophy (DMD), but it is unknown how these progress over time. Our aim was to longitudinally assess verbal span capacity and information processing speed in DMD and to explore a genotype-phenotype relation. Verbal span and processing speed scores were available of 28 males with DMD on two time-points, with a mean time interval of 28.34 months (SD = 16.09). The cohort contained of six patients missing only dystrophin isoform Dp427, sixteen missing Dp427 and Dp140, and six were undeterminable. A lower verbal span capacity was found at the first and second assessment, whereas processing speed was normal at both time-points. Post-hoc analyses suggested lower scores on verbal span and processing speed for patients missing Dp427 and Dp140. In DMD, a developmental stagnation in verbal span capacity, irrespective of normal processing speed, is detected through longitudinal follow-up. This appears more pronounced in patients missing Dp427 and Dp140. (C) 2020 European Paediatric Neurology Society. Published by Elsevier Ltd. All rights reserved. Show less
We aimed to expand our knowledge about the level of neurocognitive functioning (NCF) and health-related quality of life (HRQoL) in patients with primary and secondary brain tumors during the... Show moreWe aimed to expand our knowledge about the level of neurocognitive functioning (NCF) and health-related quality of life (HRQoL) in patients with primary and secondary brain tumors during the disease course. We found that the tumor itself has the largest negative impact on NCF and HRQoL. At group level, treatment (surgery, radiotherapy and/or chemotherapy) did not seem to have a large extra detrimental effect on the short term. However, subgroups of patients, e.g. patients with tumors in the non-dominant hemisphere and long-term survivors, appeared to be vulnerable for cognitive decline after treatment. At the individual patient level, HRQoL varied to a large degree in the first months after treatment, confirming this is a multidimensional concept and that the impact of treatment differs for the different aspects. With the results from the studies described in this thesis, treatment and individual patient care can be optimized by minimizing the negative impact of treatment, e.g. by intraoperative monitoring of cognition during awake surgery, and by counseling and rehabilitation of patients. Besides, investigators should pay attention to methodological challenges in reporting of neurocognitive outcomes in research, as reporting of these outcomes is currently not sufficient, while evidence can be of value in clinical decision-making. Show less
Background To date, no symptomatic treatment is available for patients with vascular cognitive impairment (VCI). In the proof-of-principle study Symptomatic Treatment of Vascular Cognitive... Show moreBackground To date, no symptomatic treatment is available for patients with vascular cognitive impairment (VCI). In the proof-of-principle study Symptomatic Treatment of Vascular Cognitive Impairment (STREAM-VCI), we investigated whether a single dose of a monoaminergic drug (methylphenidate) improves executive functioning and whether a single dose of a cholinergic drug (galantamine) improves memory in VCI patients. Methods STREAM-VCI is a single-center, double-blind, three-way crossover trial. We included 30 VCI patients (Mini-Mental State Examination (MMSE) >= 16 and Clinical Dementia Rating score 0.5-1.0) with cerebrovascular pathology on MRI. All patients received single doses of methylphenidate (10 mg), galantamine (16 mg), and placebo in random order on three separate study visits. We used the NeuroCart (R), a computerized test battery, to assess drug-sensitive cognitive effects. Predefined main outcomes, measured directly after a single dose of a study drug, were (i) change in performance on the adaptive tracker for executive functioning and (ii) performance on the Visual Verbal Learning Test-15 (VVLT-15) for memory, compared to placebo. We performed mixed model analysis of variance. Results The study population had a mean age of 67 +/- 8 years and MMSE 26 +/- 3, and 9 (30%) were female. Methylphenidate improved performance on the adaptive tracker more than placebo (mean difference 1.40%; 95% confidence interval [CI] 0.56-2.25; p = 0.002). In addition, methylphenidate led to better memory performance on the VVLT-15 compared to placebo (mean difference in recalled words 0.59; 95% CI 0.03-1.15; p = 0.04). Galantamine did not improve performance on the adaptive tracker and led to worse performance on delayed recall of the VVLT-15 (mean difference - 0.84; 95% CI - 1.65, - 0.03; p = 0.04). Methylphenidate was well tolerated while galantamine produced gastrointestinal side effects in a considerable number of patients. Conclusions In this proof-of-principle study, methylphenidate is well tolerated and improves executive functioning and immediate recall in patients with VCI. Galantamine did not improve memory or executive dysfunction. Results might be influenced by the considerable amount of side effects seen. Show less
Blood-brain barrier (BBB) leakage is considered an important underlying process in both cerebral small vessel disease (cSVD) and Alzheimer's disease (AD). The objective of this study was to examine... Show moreBlood-brain barrier (BBB) leakage is considered an important underlying process in both cerebral small vessel disease (cSVD) and Alzheimer's disease (AD). The objective of this study was to examine associations between BBB leakage, cSVD, neurodegeneration, and cognitive performance across the spectrum from normal cognition to dementia. Leakage was measured with dynamic contrast-enhanced magnetic resonance imaging in 80 older participants (normal cognition, n = 32; mild cognitive impairment, n 34; clinical AD-type dementia, n = 14). Associations between leakage and white matter hyperintensity (WMH) volume, hippocampal volume, and cognition (information processing speed and memory performance) were examined with multivariable linear regression and mediation analyses. Leakage within the gray and white matter was positively associated with WMH volume (gray matter, p = 0.03; white matter, p = 0.01). A negative association was found between white matter BBB leakage and information processing speed performance, which was mediated by WMH volume. Leakage was not associated with hippocampal volume. WMH pathology is suggested to form a link between leakage and decline of information processing speed in older individuals with and without cognitive impairment. (C) 2019 Elsevier Inc. All rights reserved. Show less
The ventral tegmental area dopamine (VTA-DA) mesolimbic circuit processes emotional, motivational, and social reward associations together with their more demanding cognitive aspects that involve... Show moreThe ventral tegmental area dopamine (VTA-DA) mesolimbic circuit processes emotional, motivational, and social reward associations together with their more demanding cognitive aspects that involve the mesocortical circuitry. Coping with stress increases VTA-DA excitability, but when the stressor becomes chronic the VTA-DA circuit is less active, which may lead to degeneration and local microglial activation. This switch between activation and inhibition of VTA-DA neurons is modulated by e.g. corticotropin-releasing hormone (CRH), opioids, brain-derived neurotrophic factor (BDNF), and the adrenal glucocorticoids. These actions are coordinated with energy-demanding stress-coping styles to promote behavioral adaptation. The VTA circuits show sexual dimorphism that is programmed by sex hormones during perinatal life in a manner that can be affected by glucocorticoid exposure. We conclude that insight in the role of stress in VTA-DA plasticity and connectivity, during reward processing and stress-coping, will be helpful to better understand the mechanism of resilience to breakdown of adaptation. Show less
