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Contains fulltext : 195401.pdf (Author’s version postprint ) (Open Access) We know how age affects the brain during lab-based tasks, but what about situations truer to everyday life, such as watching movies? We measured fMRI activity while participants (N=577) from the Cambridge Centre for Ageing and Neuroscience (www.cam-can.com) watched a movie. Watching the same movie induces significant inter-subject synchronization of brain activity across participants. These cross-subject correlations suggest that viewers are processing incoming information in a similar (or shared) way. We show that with advancing age, synchrony is preserved in some areas, including the language network, but decreased in others, including the medial prefrontal cortex, medial temporal lobe and fronto-parietal network. Synchrony declines were driven by more idiosyncratic responding in older adults and were associated with regionally-distinct temporal profiles and functional connectivity patterns, as well as declines in white matter integrity. These findings suggest that areas involved in language processing remain intact with age, while regions involved in attentional control and memory may show age-related declines, even in situations similar to daily life. 15 p.

Item does not contain fulltext Background. Visuospatial neglect is a disabling syndrome with serious consequences for activities in daily life. This study investigated the effect of adaptive cueing during a reading task as a possible treatment for neglect by including (1) a task relevant for the patient's daily life, (2) a fading out procedure to stimulate independent orientation to the left by self-cueing, and (3) a clear definition of neglect severity for the adaptive treatment protocol. Methods. A randomized controlled crossover design was used, including 26 patients from an early rehabilitation unit with left-sided visuospatial neglect after stroke or hemorrhage. They were examined twice at baseline (T1, T2), after 15 daily sessions in 1 condition (T3), and again after 15 daily sessions in the other condition (T4). The intervention condition included a daily reading task combined with endogenous and exogenous cues provided by a therapist, which were continuously reduced after a patient had reached a defined level of performance. The control condition consisted of a neuropsychological treatment of the same length, not targeting visuospatial attention. Results. Significant improvements were shown after intervention on scores for reading (word and text reading), daily life activities (Catherine Bergego Scale), Line Bisection, and the Clock Drawing Task. Conclusion. This study shows that adaptive cueing in a reading task can improve neglect symptoms by using an intensive intervention lasting 3 weeks. 11 p.

Contains fulltext : 198590.pdf (Publisher’s version ) (Open Access) Life challenges are not only for individuals, but also faced by a member of a system, such as family. The ability to face this challenge is known as resilience. This research aims to develop a family resilience scale to provide instruments for assessment, research and intervention, especially for families who have children with special needs (CSN). The development of this scale involved 41 families who were chosen using accidental sampling technique. The data analyzed through exploratory factor analysis (EFA), proceeded by confirmatory factor analysis (CFA) confirmed that there were three dimensions of family with CSN resilience scale: acceptance, management, and support. This three-factor model fits the data. The three dimensions turned out to measure one construct, the resilience of family with CSN. This scale has high reliability. Thus, family resilience scale of family with CSN has good psychometric properties for further use. 14 p.

Background Neuroimaging in older adults commonly reveals signs of cerebral small vessel disease (SVD). SVD is believed to be caused by chronic hypoperfusion based on animal models and longitudinal studies with inter-scan intervals of years. Recent imaging evidence, however, suggests a role for acute ischaemia, as indicated by incidental diffusion-weighted imaging lesions (DWI+ lesions), in the origin of SVD. Furthermore, it becomes increasingly recognised that focal SVD lesions likely affect the structure and function of brain areas remote from the original SVD lesion. However, the temporal dynamics of these events are largely unknown. Aims (1) To investigate the monthly incidence of DWI+ lesions in subjects with SVD; (2) to assess to which extent these lesions explain progression of SVD imaging markers; (3) to investigate their effects on cortical thickness, structural and functional connectivity and cognitive and motor performance; and (4) to investigate the potential role of the innate immune system in the pathophysiology of SVD. Design/methods The RUN DMC – InTENse study is a longitudinal observational study among 54 non-demented RUN DMC survivors with mild to severe SVD and no other presumed cause of ischaemia. We performed MRI assessments monthly during 10 consecutive months (totalling up to 10 scans per subject), complemented with clinical, motor and cognitive examinations. Discussion Our study will provide a better understanding of the role of DWI+ lesions in the pathophysiology of SVD and will further unravel the structural and functional consequences and clinical importance of these lesions, with an unprecedented temporal resolution. Understanding the role of acute, potentially ischaemic, processes in SVD may provide new strategies for therapies.

Contains fulltext : 192386.pdf (Publisher’s version ) (Open Access) The present study focused on interference in a group of patients with amnesia due to Korsakoff's syndrome (KS) within the domain of spatial memory. An object–location memory task was used in which participants first learned an array of objects on a computer screen, followed by a reconstruction of the object positions. Next a trial was given in which the same objects were presented only now in different locations. Participants had to place the objects a second time but at the new locations. This was repeated for seven pairs of baseline/interference trials. Both Korsakoff patients and matched controls did worse on the interference trials than on the baseline trials, indicating that it is difficult to relearn new spatial locations for objects that previously were remembered in other locations. When computing relative interference effects (that is the percentage change from baseline in the interference trials), Korsakoff patients were less affected than controls. It is discussed in how far interference depends on the strength of the original memories, which are markedly lower in KS patients. 8 p.

It is assumed that learning on the Serial Reaction Time (SRT) task is related to learning involved in social skill development affected in autism, but this assumption has hardly been investigated. We have therefore examined associations between SRT task learning and social impairment measured by the Social Responsiveness Scale in 72 autistic and non-autistic adults. Results revealed a positive correlation between deterministic sequence learning, putatively involving explicit learning, and social impairment in autistic adults but not in non-autistic adults. No correlations with probabilistic learning were found. These results suggest that the type of learning that helps autistic adults during a deterministic SRT task hinders them during social development, and call for further investigating the ecological validity of the SRT task. Electronic supplementary material The online version of this article (10.1007/s10803-018-3529-6) contains supplementary material, which is available to authorized users.

Item does not contain fulltext Background: Recently, we proposed a model explaining the origin of fatigue in multiple sclerosis (MS) patients. This model assumes that the feeling of fatigue results from inflammation-induced information processing within interoceptive brain areas. Objectives: To investigate the association between self-reported cognitive fatigue and structural integrity of interoceptive brain areas in MS patients. Methods: 95 MS patients and 28 healthy controls participated in this study. All participants underwent diffusion tensor MRI and fractional anisotropy data were calculated for the amygdala, the stria terminalis and the corpus callosum, a non-interoceptive brain area. Based on the cognitive fatigue score of the Fatigue Scale for Motor and Cognition, patients were divided into moderately cognitively fatigued (cognitive fatigue score >= 28) and cognitively non-fatigued (cognitive fatigue score < 28) MS patients. Healthy controls were recruited as a third group. Repeated measures analyses of covariance, controlling for age, depression and brain atrophy, were performed to investigate whether the factor Group had a significant effect on the fractional anisotropy data. Results: A significant effect of Group was observed for the amygdala (F=3.389, p=0.037). MS patients without cognitive fatigue presented lower values of the amygdala than MS patients with cognitive fatigue and healthy controls. For the stria terminalis and the corpus callosum, no main effect of Group was observed. Conclusion: The structural integrity of the amygdala in non-fatigued MS patients appears to be reduced. According to our model this might indicate that the absence of fatigue in non-fatigued MS patients might result from disturbed inflammation-induced information processing in the amygdala. 6 p.

Willem Verhoeven,1,2 Jos Egger,1,3 Emmy Räkers,4 Arjen van Erkelens,5 Rolph Pfundt,5 Marjolein H Willemsen5 1Vincent van Gogh Institute for Psychiatry, Centre of Excellence for Neuropsychiatry, Venray, the Netherlands; 2Department of Psychiatry, Erasmus University Medical Centre, Rotterdam, the Netherlands; 3Donders Institute for Brain, Cognition and Behaviour, Radboud University, Nijmegen, the Netherlands; 4ASVZ, Centre for People with Intellectual Disabilities, Sliedrecht, the Netherlands; 5Department of Human Genetics, Radboud University Medical Centre, Nijmegen, the Netherlands Abstract: The additional sex combs like 3 gene is considered to be causative for the rare Bainbridge-Ropers syndrome (BRPS), which is characterized by severe intellectual disability, neonatal hypotonia, nearly absent development of speech and language as well as several facial dysmorphisms. Apart from disruptive autistiform behaviors, sleep disturbances and epileptic phenomena may be present. Here, a 47-year-old severely intellectually disabled male is described in whom exome sequencing disclosed a novel heterozygous frameshift mutation in the ASXL3 gene leading to a premature stopcodon in the last part of the last exon. Mutations in this very end 3' of the gene have not been reported before in BRPS. The phenotypical presentation of the patient including partially therapy-resistant epilepsy starting in later adulthood shows overlap with BRPS, and it was therefore concluded that the phenotype is likely explained by the identified mutation in ASXL3. Keywords: Bainbridge-Ropers syndrome, ASLX3, frameshift mutation, epilepsy, intellectual disability, array analysis, whole exome sequencing, autism spectrum disorder

Objective A lack of empathy and the presence of predatory tendencies are considered key features of psychopathic meanness. Previous electrophysiological studies on empathy in relation to psychopathic traits have focused mainly on empathy for pain; therefore, little is known about the electrophysiological correlates of empathy in aggressive situations that are particularly relevant for psychopathic meanness. Method We employed electroencephalography in a community sample (n = 70), the majority of whom had attained a higher level of education. All participants were screened for not having psychiatric conditions or criminal history. The P3 and late positive potential (LPP) event-related potentials and mu rhythm suppression were examined as indices of empathic processing during the observation of situations in which victims of aggression were depicted. Results As predicted, it was found that persons with elevated levels of psychopathic meanness scored lower on trait empathy and assigned higher positive valence to the aggression scenes. It is interesting that those scoring higher on meanness also scored higher on empathy for the perpetrator. In addition, it was found that psychopathic meanness was negatively related to LPP amplitudes following pictures of aggressive situations. No significant associations were found between meanness and the P3 or between meanness and mu suppression. Conclusions This study was the first to assess the electrophysiological signature of empathy during the processing of pictures depicting aggressive situations and the relationships with psychopathic meanness. The outcomes highlight the need for more integrative approaches to further study the complex pattern of relationships between empathy and psychopathic meanness. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

Item does not contain fulltext Objective: Parental rejection in childhood is associated with the increased risk of aggression in adulthood and is thought to contribute to the development of inaccurate beliefs regarding own or others' behavior (i.e., cognitive distortion) as well. Different forms of aggression are thought to be linked to different types of cognitive distortions. This, however, is unclear in adults. Additionally, it is unknown if parental rejection predicts the presence of aggression and cognitive distortions in adults displaying severe aggression. Method: One hundred twenty-three adult forensic psychiatric outpatients with aggression regulation problems were recruited. Least absolute shrinkage and selection operator (Lasso) regression analysis and path analyses were conducted to investigate distinct patterns of cognitive distortions, as measured by use of the How I Think Questionnaire, and the role of perceived parental rejection, as measured by use of the Parental Rejection and Acceptance Questionnaire. Results: Cognitive distortions related to opposition-defiance (e.g. disrespecting rules) and to physical aggression were most strongly associated with the disposition to act aggressively. Furthermore, a direct association was found between parental rejection and this current disposition. This association was partially mediated by cognitive distortions related to opposition-defiance. Conclusion: The current study supports the notion that parental rejection has profound consequences on adult behavior. Acknowledgement of the impact of cognitive distortions on current aggression might be of importance for treatment. A stronger focus on altering distinct cognitive distortions may be more successful in reducing aggression. 10 p.

Contains fulltext : 199705.pdf (Publisher’s version ) (Open Access) Objective: Specific knowledge on neurocognitive functioning in (syndrome based) intellectual disability (ID) is important for the assessment, treatment and support of patients in whom this condition is present. The present study investigates the applicability of computerized neurocognitive testing in patients with rare monogenetic ID disorders by (1) determining the developmental age at which the use is contributive and (2) investigating the specificity of the tests for neurocognitive functions, independent of the ID. Method: A total of 56 patients with monogenetic ID disorders, including Kleefstra Syndrome (KS; n = 24), and a contrast group of various rare disorders (n = 32) participated. Assessments included (a) the Vineland Adaptive Behavior Scale (VABS) interview to calculate developmental age and (b) four simplified subtests of the Cambridge Neuropsychological Test Automated Battery (CANTAB). A cut-off in developmental age was estimated based on the ability to complete the CANTAB-tasks. A developmental age of 2,5 years and older allows practical application in our cohort. Results: There was no significant correlation between developmental age and results on cognitive tests (range: -0,171 0,07). A between-group comparison shows a larger dropout in the KS sub cohort (based on cross tabulation) and longer latencies on the motor screening test. Conclusions: Our results indicate that simplified CANTAB tasks are suitable for application in the ID population to unravel individual neurocognitive characteristics and, hence also, syndrome specific neurocognitive features. Furthermore, successful employment of computerized testing in this complex population may be the only way to avoid the restraints of standard classificatory clinical procedures that aim at categories of patients rather than at the individual patient with its unique cognitive neuropsychiatric complexion. 8 p.

Contains fulltext : 192370.pdf (Publisher’s version ) (Open Access) Objective: The current article set out to review all research conducted to date investigating prospective memory (PM) in autism. Method: All studies on PM in autism are first described, followed by a critical review and discussion of experimental findings within the multiprocess framework. PM in autism is then considered through an embodied predictive coding account of autism. Results: Overall, despite somewhat inconsistent methodologies, a general deficit in PM in autism is observed, with evidence mostly in line with the multiprocess framework. That is, for tasks that are high in cognitive and attentional demand (e.g. time-based tasks; event-based cues of non-focality or low salience) PM performance of autistic participants is impaired. Building upon previous work in predictive-coding, and the way in which expected precision modulates attention, we postulate mechanisms that underpin PM and the potential deficits seen in autism. Furthermore, a unifying predictive-coding account of autism is extended under embodied predictive-coding models, to show how a predictive-coding impairment accounts not only for characteristic autistic difficulties, but also for commonly found differences in autistic movement. Conclusions: We show how differences in perception and action, core to the development of autism, lead directly to problems seen in PM. Using this link between movement and PM, we then put forward a number of holistic, embodied interventions to support PM in autism. 35 p.

Item does not contain fulltext Defensive functioning is considered one of the core aspects of personality functioning and its maturity level is regarded an important predictor of psychopathology and more specific personality pathology. The current investigation assesses the relation between overall defensive functioning, as measured by the Defense Style Questionnaire-42 (DSQ-42), and higher order models of psychopathology as measured by the Minnesota Multiphasic Personality Inventory-2-Restructured Form (MMPI-2-RF). The DSQ-42 and MMPI-2-RF was completed by 383 patients. We analysed the MMPI-2-RF personality and psychopathology as measured with the Restructured Clinical scales and the Personality Psychopathology Five-revised scales using Goldberg's Bass Ackwards Method. Higher order dimensions of personality and psychopathology in the current investigation demonstrated structural similarity with previously reported higher order models. Next we examined the optimal level of differentiation of defensive functioning, as measured by the DSQ-42 Total and Overall Defensive Functioning scores, to personality and psychopathology at each succeeding level of the hierarchical factor structures. Results indicated that immature defense mechanisms exemplify strong correlations with internalizing pathology (i.e., Demoralisation and Introversion), but not with externalizing pathology and thought disorder. The differentiation of defensive functioning from higher order models of psychopathology and maladaptive personality traits seems to be limited, based on the current results. The DSQ-42 appeared to have a large overlap and correlations with internalizing pathology, which appeared to be due to its item content: mostly intrapsychic and immature defenses. Theoretical and clinical implications considering the use of the DSQ are discussed. 13 p.

Background: Serum TGF-beta 1 concentrations are reported to be elevated in chronic fatigue syndrome (CFS). However, measurement of circulating cytokines is a complex procedure and control of pre-analytical procedures is essential. The objective of the current study was to measure circulating TGF-beta 1 concentrations in CFS patients compared to healthy controls, taking into account differences in pre-analytical procedures.Methods: Two cohorts of female CFS patients were included. In both studies patients were asked to bring a healthy, age-matched control. At baseline, TGF-beta 1 levels were measured in plasma and additionally P-selectin, a marker of platelet activity, was determined in a subgroup of participants.Results: 50 patients and 48 controls were included in cohort I, and 90 patients and 29 controls in cohort II. Within the cohorts there were no differences in TGF-beta 1 concentrations. However, between the cohorts there was a large discrepancy, which appeared to be caused by differences in g-force of the centrifuges used. The lower g-force used in cohort II (1361 g) caused more platelet activation, reflected by higher p-selectin concentrations, compared to cohort I (p < 0.0001), which was confirmed in a second independent experiment. There was a correlation between TGF-beta 1 and p-selectin concentrations (r 0.79, p < 0.0001).Conclusion: These results demonstrate that control of pre-analytical procedures is an essential aspect when measuring circulating cytokines. No evidence for enhanced TGF-beta 1 in patients with CFS was found.

Contains fulltext : 194837.pdf (Publisher’s version ) (Open Access) Autism spectrum disorder (ASD) and specific language impairment (SLI) are two neurodevelopmental disorders characterized by deficits in verbal and nonverbal communication skills. These skills are thought to develop largely through implicit - or automatic - learning mechanisms. The aim of the current paper was to investigate the role of implicit learning abilities in the atypical development of communication skills in ASD and SLI. In the current study, we investigated Response Times (RTs) and Event Related Potentials (ERPs) during implicit learning on a Serial Reaction Time (SRT) task in a group of typically developing (TD) children (n = 17), a group of autistic children (n = 16), and a group of children with SLI (n = 13). Findings suggest that learning in both ASD and SLI are similar to that in TD. However, electrophysiological findings suggest that autistic children seem to rely mainly on more automatic processes (as reflected by an N2b component), whereas the children with SLI seem to rely on more controlled processes (as reflected by a P3 component). The TD children appear to use a combination of both learning mechanisms. These findings suggest that clinical interventions should aim at compensating for an implicit learning deficit in children with SLI, but not in children with ASD. Future research should focus on developmental differences in implicit learning and related neural correlates in TD, ASD, and SLI. Lay Summary: Autism and Specific Language Impairment (SLI) are two disorders characterized by problems in social communication and language. Social communication and language are believed to be learned in an automatic way. This is called "implicit learning". We have found that implicit learning is intact in autism. However, in SLI there seems different brain activity during implicit learning. Maybe children with SLI learn differently, and maybe this different learning makes it more difficult for them to learn language. 12 p.

Contains fulltext : 191183.pdf (Publisher’s version ) (Closed access) Objective: To assess the pain prevalence, pain intensity, and pain medication use in older patients with a diagnosed subtype of dementia, mild cognitive impairment (MCI), or subjective cognitive impairment (SCI). Design: Cross-sectional. Setting: Outpatient memory clinics. Subjects: In total, 759 patients with Alzheimer's disease (AD), vascular dementia, mixed AD and vascular pathology (MD), frontotemporal dementia, dementia with Lewy Bodies, MCI, or SCI. Methods: Self-reported presence and intensity of pain, prescribed medication, and related descriptive variables were given for each group. To compare groups on prevalence of pain, logistic regression analyses were adjusted for age, gender, and mood. Differences in pain intensity were tested using a Kruskall-Wallis test, and differences in analgesic use with chi-square analyses. Results: Pain prevalence ranged from 34% in MD to 50% in SCI. AD (odds ratio [OR] = 0.56, 95% confidence interval [CI] = 0.34-0.93) and MD (OR = 0.45, CI = 0.20-0.98) patients were less likely to report pain than SCI patients. The self-reported pain intensity did not differ between groups. In total, 62.5% of patients did not use any analgesic medication despite being in pain, which did not differ significantly between groups. Conclusion: Outpatient memory clinic patients with mild to moderate AD and MD are less likely to report pain than patients with SCI. No difference in self-reported pain intensity was present. The high percentage of patients with and without dementia who do not use analgesics when in pain raises the question of whether pain treatment is adequate in older patients. 8 p.

Contains fulltext : 197208.pdf (Publisher’s version ) (Closed access) Objective: To investigate alterations in tactile, pain thresholds and pain tolerance thresholds in patients with endometriosis using a multimodality approach. Design: Cross-sectional study. Setting: Multidisciplinary referral center. Patient(s): Women with proven endometriosis (N = 35) and healthy controls (N = 38). Intervention(s): Pain processing was tested using quantitative sensory testing (QST) to investigate sensation, pain, and pain tolerance thresholds for thermal, electrical, and pressure stimuli. Main Outcome Measure(s): Differences in QST measures in patients with endometriosis and in healthy controls on the endometriosis site and control sites, and the association between QST outcomes and patient characteristics. Result(s): We observed a significantly decreased pain tolerance in patients with endometriosis, independent of clinical pain intensity or revised American Society for Reproductive Medicine stage, compared with healthy controls. Conclusion(s): Increasing knowledge concerning mechanisms underlying the pain of women with endometriosis creates opportunities to develop new treatment options. More attention should be paid not only to treat endometriosis in a surgical or pharmacologic way, but also to desensitize by pain education or cognitive therapy. 11 p.

Contains fulltext : 195873.pdf (Publisher’s version ) (Open Access) Of the triad of symptoms found in autism spectrum disorder (ASD), that is, social impairments, communication difficulties and repetitive interests and behaviour, the social impairments are the most stable and common throughout the lifespan. They typically manifest themselves in abnormalities as reciprocal interactions and difficulties in the expression and recognition of emotions. Although peer interactions become especially important during adolescence, little is known about the mentalizing abilities of high-functioning adolescents with ASD. Here, we compared the mentalizing skills and emotion recognition abilities of 21 high-functioning adolescents with ASD and 21 matched controls. All adolescents had estimated above-average verbal intelligence levels. Spontaneous social abilities and task-related social abilities were measured using questionnaires, tasks and the Autism Diagnostic Observation Schedule. Results confirm social impairment in daily life situations in adolescents with ASD, but were not found on experimental tasks of social cognition. The use of more explicit cognitive or verbally mediating reasoning techniques and a lesser tendency of high-functioning adolescents with ASD to search for and use social information in natural environments are further discussed. 11 p.

Contains fulltext : 191641.pdf (Publisher’s version ) (Open Access) Previous research addressing motivational effects on cognitive control adaptations primarily manipulated external rewards. In the present study, we examined whether achievement motivation, reflecting intrinsic motivation, modulates cognitive control adaptations. In each of two experiments, students were divided into a high achievement motivation group (HAM; Experiment 1: N = 36; Experiment 2: N = 39) and a low achievement motivation group (LAM; Experiment 1: N = 30; Experiment 2: N = 39) on the basis of the Achievement Motivation Scale. Cognitive control adaptations were assessed by sequential congruency effects (SCEs) in Flanker tasks. Using a standard Flanker task in Experiment 1 and examining response times, the HAM but not LAM participants showed evidence of cognitive control adaptations. Because SCEs in a standard Flanker task may reflect lower-level, bottom-up processes rather than cognitive control adaptations, we used an adapted version of the Flanker task in Experiment 2 that controlled for the potential influence of such processes. Experiment 2 again revealed evidence of SCEs in the HAM but not LAM participants. These results suggest that cognitive control adaptions may be modulated by achievement motivation. Such potential modulation could be taken into account when evaluating results of previous and future fundamental and applied studies on cognitive control adaptations. 13 p.

Contains fulltext : 195876.pdf (Publisher’s version ) (Open Access) The present paper describes the Box Task, a paradigm for the computerized assessment of visuospatial working memory. In this task, hidden objects have to be searched by opening closed boxes that are shown at different locations on the computer screen. The set size (i.e., number of boxes that must be searched) can be varied and different error scores can be computed that measure specific working memory processes (i.e., the number of within-search and between-search errors). The Box Task also has a developer's mode in which new stimulus displays can be designed for use in tailored experiments. The Box Task comes with a standard set of stimulus displays (including practice trials, as well as stimulus displays with 4, 6, and 8 boxes). The raw data can be analyzed easily and the results of individual participants can be aggregated into one spreadsheet for further statistical analyses. 7 p.

Item does not contain fulltext Parkinson's disease (PD) is a chronically progressive neurodegenerative disease, with its main pathological hallmarks being a dramatic loss of dopaminergic neurons predominantly in the Substantia Nigra (SN), and the formations of intracytoplasmic Lewy bodies and dystrophic neurites. Alpha-synuclein (α-syn), widely recognized as the most prominent element of the Lewy body, is one of the representative hallmarks in PD. However, the mechanisms behind the increased α-syn expression and aggregation have not yet been clarified. To examine what causes α-syn expression to increase, we analyzed the pattern of gene expression in the SN of mice intoxicated with 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP), where down-regulation of dopaminergic cells occurred. We identified serum- and glucocorticoid-dependent kinase 1 (SGK1) as one of the genes that is evidently downregulated in chronic MPTP-intoxication. The results of Western blot analyses showed that, together with the down-regulation of dopaminergic cells, the decrease in SGK1 expression increased α-syn expression in the SN in a chronic MPTP-induced Parkinsonism mouse. For an examination of the expression correlation between SGK1 and α-syn, SH-5YSY cells were knocked down with SGK1 siRNA then, the downregulation of dopaminergic cells and the increase in the expression of α-syn were observed. These results suggest that decreased expression of SGK1 may play a critical role in increasing the expression of α-syn, which is related with dopaminergic cell death in the SN of chronic MPTP-induced Parkinsonism mice and in SH-SY5Y cells. 7 p.

General intelligence is a psychological construct that captures in a single metric the overall level of behavioural and cognitive performance in an individual. While previous research has attempted to localise intelligence in circumscribed brain regions, more recent work focuses on functional interactions between regions. However, even though brain networks are characterised by substantial modularity, it is unclear whether and how the brain’s modular organisation is associated with general intelligence. Modelling subject-specific brain network graphs from functional MRI resting-state data (N = 309), we found that intelligence was not associated with global modularity features (e.g., number or size of modules) or the whole-brain proportions of different node types (e.g., connector hubs or provincial hubs). In contrast, we observed characteristic associations between intelligence and node-specific measures of within- and between-module connectivity, particularly in frontal and parietal brain regions that have previously been linked to intelligence. We propose that the connectivity profile of these regions may shape intelligence-relevant aspects of information processing. Our data demonstrate that not only region-specific differences in brain structure and function, but also the network-topological embedding of fronto-parietal as well as other cortical and subcortical brain regions is related to individual differences in higher cognitive abilities, i.e., intelligence.

Hyperpolarization-activated cyclic nucleotide-gated cation (HCN) channels have important functions in controlling neuronal excitability and generating rhythmic oscillatory activity. The role of tetratricopeptide repeat-containing Rab8b-interacting protein (TRIP8b) in regulation of hyperpolarization-activated inward current, I h, in the thalamocortical system and its functional relevance for the physiological thalamocortical oscillations were investigated. A significant decrease in I h current density, in both thalamocortical relay (TC) and cortical pyramidal neurons was found in TRIP8b-deficient mice (TRIP8b−/−). In addition basal cAMP levels in the brain were found to be decreased while the availability of the fast transient A-type K+ current, I A, in TC neurons was increased. These changes were associated with alterations in intrinsic properties and firing patterns of TC neurons, as well as intrathalamic and thalamocortical network oscillations, revealing a significant increase in slow oscillations in the delta frequency range (0.5–4 Hz) during episodes of active-wakefulness. In addition, absence of TRIP8b suppresses the normal desynchronization response of the EEG during the switch from slow-wave sleep to wakefulness. It is concluded that TRIP8b is necessary for the modulation of physiological thalamocortical oscillations due to its direct effect on HCN channel expression in thalamus and cortex and that mechanisms related to reduced cAMP signaling may contribute to the present findings. Electronic supplementary material The online version of this article (10.1007/s00429-017-1559-z) contains supplementary material, which is available to authorized users.

Contains fulltext : 196779pre.pdf (Author’s version preprint ) (Open Access) Contains fulltext : 196779.pdf (Publisher’s version ) (Open Access) Different frequency bands in the electroencephalogram are postulated to support distinct language functions. Studies have suggested that alpha-beta power decreases may index word-retrieval processes. In context-driven word retrieval, participants hear lead-in sentences that either constrain the final word ("He locked the door with the") or not ("She walked in here with the"). The last word is shown as a picture to be named. Previous studies have consistently found alpha-beta power decreases prior to picture onset for constrained relative to unconstrained sentences, localised to the left lateral-temporal and lateral-frontal lobes. However, the relative contribution of temporal versus frontal areas to alpha-beta power decreases is unknown. We recorded the electroencephalogram from patients with stroke lesions encompassing the left-lateral temporal and inferior parietal regions or left-lateral frontal lobe and from matched controls. Individual-participant analyses revealed a behavioural sentence context facilitation effect in all participants, except for in the two patients with extensive lesions to temporal and inferior-parietal lobes. We replicated the alpha-beta power decreases prior to picture onset in all participants, except for in the two same patients with extensive posterior lesions. Thus, whereas posterior lesions eliminated the behavioural and oscillatory context effect, frontal lesions did not. Hierarchical clustering analyses of all patients’ lesion profiles, and behavioural and electrophysiological effects identified those two patients as having a unique combination of lesion distribution and context effects. These results indicate a critical role for the left lateral-temporal and inferior parietal lobes, but not frontal cortex, in generating the alpha-beta power decreases underlying context-driven word production. 8 p.

Contains fulltext : 178408.pdf (Publisher’s version ) (Open Access) Sleep spindles are phasic bursts of thalamo-cortical activity, visible in the cortex as transient oscillations in the sigma range (usually defined in humans as 12-14 or 9-16 Hz). They have been associated with sleep-dependent memory consolidation and sleep stability in humans and rodents. Occurrence, frequency, amplitude and duration of sleep spindles co-vary with age, sex and psychiatric conditions. Spindle analogue activity in dogs has been qualitatively described, but never quantified and related to function. In the present study we used an adjusted version of a detection method previously validated in children to test whether detections in the dogs show equivalent functional correlates as described in the human literature. We found that the density of EEG transients in the 9-16 Hz range during non-REM sleep relates to memory and is characterized by sexual dimorphism similarly as in humans. The number of transients/minute was larger in the learning condition and for female dogs, and correlated with the increase of performance during recall. It can be concluded that in dogs, automatic detections in the 9-16 Hz range, in particular the slow variant (

Item does not contain fulltext The authors investigated retrospective timing in participants with Korsakoff's syndrome. Patients were assessed on four retrospective tasks on which they were instructed to read three-digit numbers aloud (15 seconds), fill connected squares (30 seconds), decide whether words were abstract or concrete (45 seconds), or read aloud a text about mushroom picking (60 seconds). Participants were not aware of the task's timing until the end of the tasks, when they were asked to estimate the elapsed time. Results revealed an underestimation of the elapsed time in Korsakoff participants, suggesting that time is perceived to pass quickly for these participants. 7 p.

Item does not contain fulltext Antisociale personen vormen een grote last voor de maatschappij, onder andere omdat ze voor veel emotionele en financiële schade zorgen. Binnen de forensische psychiatrie wordt geprobeerd om deze personen te helpen met het verder ontwikkelen van hun vermogen om gedrag te reguleren. Helaas leidt deze hulp niet altijd tot de beoogde resultaten, omdat antisociale populaties heterogeen zijn, met sterke interpersoonlijke verschillen in de neurobiologische en cognitieve factoren die tot de antisociale gedragingen leiden. Personen met psychopathie vormen een van de meest extreme subpopulaties en zijn ook relatief moeilijk te behandelen. Om deze mensen beter te kunnen helpen, is het nodig om behandelinterventies te ontwikkelen die rekening houden met hun cognitieve verwerkingsstijl, omdat aan antisociaal gedrag een grote diversiteit van neurocognitieve afwijkingen ten grondslag zou kunnen liggen. Recent onderzoek laat zien dat er een subgroep antisociale personen is met psychopathische kenmerken die zijn verbonden aan verminderd leren van negatieve uitkomsten (zoals leren van fouten), maar ook dat de manier waarop informatie wordt aangeboden (bijv. context) relevant is voor gedragsaanpassing. Meer inzicht in de neurocognitieve mechanismen die zijn aangedaan in psychopathie, zou op termijn kunnen leiden tot de ontwikkeling van behandelinterventies die aansluiten bij de cognitieve verwerkingsstijl van deze groep antisociale personen. 6 p.

Self-awareness is often impaired after acquired brain injury (ABI) and this hampers rehabilitation, in general: unrealistic reports by patients about their functioning and poor motivation and compliance with treatment. We evaluated a self-awareness treatment that was part of a treatment protocol on executive dysfunction (Spikman, Boelen, Lamberts, Brouwer, & Fasotti, 2010). A total of 63 patients were included, aged 17–70, suffering non-progressive ABI, and minimum time post-onset of 3 months. Self-awareness was measured by comparing the patient's Dysexecutive Questionnaire (Wilson, Alderman, Burgess, Emslie, & Evans, 1996) score with that of an independent other. As emotion recognition is associated with self-awareness and influences the effect of rehabilitation treatment, we assessed this function using the Facial Expressions of Emotion-Stimuli and Tests (Young, Perrett, Calder, Sprengelmeyer, & Ekman, 2002). Results showed that patients in the experimental treatment group (n= 29) had better self-awareness after training than control patients (n= 34). Moreover, our results confirmed that the level of self-awareness before treatment was related to emotion recognition. Hence, self-awareness can improve after neuropsychological treatment fostering self-monitoring. Since neuropsychological treatment involves social learning, impairments in social cognition should be taken into account before starting and during treatment.

Item does not contain fulltext Among criminal offenders, two subtypes of antisocial traits, psychopathy and externalizing-only, are associated with an especially elevated risk for substance use disorders (SUDs). The present study examined the associations of these traits with patterns of substance misuse. In a sample of 1410 male offenders, we used diagnoses for alcohol, cannabis, opioids, and stimulants to examine the association between antisocial traits and SUD severity, as well as, age at substance use initiation. Results indicated that externalizing-only, but not psychopathic, traits predicted greater severity of SUDs (i.e. increased likelihood of dependence) across all substances. By contrast, psychopathic, but not externalizing-only, traits predicted earlier initiation of use across all substances. These differential patterns of substance misuse may be a reflection of distinct psychobiological processes. Ultimately, parsing the patterns of substance use across a continuum of clinically heterogeneous samples, rather than within circumscribed diagnostic categories, might help to refine the phenotype and improve the prediction of substance-related problems. 16 p.

Item does not contain fulltext Background: Psychopathy has repeatedly been linked to disturbed associative learning from aversive events (i.e., threat conditioning). Optimal threat conditioning requires the generation of internal representations of stimulus-outcome contingencies and the rate with which these may change. Because mental representations are imperfect, there will always be uncertainty about the accuracy of representations in the brain (i.e., representational uncertainty). However, it remains unclear i) to what extent threat conditioning is susceptible to different types of uncertainty in representations about contingencies during the acquisition phase and ii) how representational uncertainty relates to psychopathic features. Methods: A computational model was applied to functional neuroimaging data to estimate uncertainty in representations of contingencies (CoUn) and the rate of change of contingencies (RUn), respectively, from brain activation during the acquisition phase of threat conditioning in 132 adolescents at risk of developing antisocial personality profiles. Next, the associations between these two types of representational uncertainty and psychopathy-related dimensions were examined. Results: The left and right amygdala activation were associated with CoUn, while the bilateral insula and the right amygdala were associated with RUn. Different patterns of relationships were found between psychopathic features and each type of uncertainty. Callous-unemotional traits and impulsive-irresponsible traits uniquely predicted increased CoUn, while only impulsive-irresponsible traits predicted increased RUn. Conclusions: The findings suggest that i) the insula and amygdala differ in how these regions are affected by different types of representational uncertainty during threat conditioning, and ii) CoUn and RUn have different patterns of relationships with psychopathy-related dimensions. 7 p.

Item does not contain fulltext Franz Joseph Gall (1758-1828) introduced a new theory of mind and brain at the end of the eighteenth century, which he referred to as organology, dealing with mental functions and their cortical localizations. Gall wrote that observations regarding the verbal learning capacities of his schoolmates brought about his new way of thinking. This widely accepted view, however, requires qualification. Although Gall's experiences and observations as a schoolboy were relevant, especially for his craniology, these childhood memories might have been recalled and reinterpreted after he had started to think about the faculties of mind --- specifically after he had met Bianchi, a 5-year-old girl with a special talent for music. 9 p.

Contains fulltext : 179660.pdf (Publisher’s version ) (Open Access) In this review, we present a survey on Korsakoff's syndrome (KS), a residual syndrome in patients who suffered from a Wernicke encephalopathy (WE) that is predominantly characterized by global amnesia, and in more severe cases also by cognitive and behavioral dysfunction. We describe the history of KS and its definition, its epidemiology, and the lack of consensus criteria for its diagnosis. The cognitive and behavioral symptoms of KS, which include anterograde and retrograde amnesia, executive dysfunction, confabulation, apathy, as well as affective and social-cognitive impairments, are discussed. Moreover, recent insights into the underlying neurocognitive mechanisms of these symptoms are presented. In addition, the evidence so far on the etiology of KS is examined, highlighting the role of thiamine and alcohol and discussing the continuity hypothesis. Furthermore, the neuropathology of KS is reviewed, focusing on abnormalities in the diencephalon, including the mammillary bodies and thalamic nuclei. Pharmacological treatment options and nonpharmacological interventions, such as those based on cognitive rehabilitation, are discussed. Our review shows that thiamine deficiency (TD) is a crucial factor in the etiology of KS. Although alcohol abuse is by far the most important context in which TD occurs, there is no convincing evidence for an essential contribution of ethanol neurotoxicity (EN) to the development of WE or to the progression of WE to KS. Future research on the postmortem histopathological analysis of brain tissues of KS patients is crucial for the advancement of our knowledge of KS, especially for associating its symptoms with lesions in various thalamic nuclei. A necessary requirement for the advancement of studies on KS is the broad acceptance of a comprehensive definition and definite diagnostic criteria. Therefore, in this review, we propose such a definition of KS and draft outlines for prospective diagnostic criteria. 16 p.

Contains fulltext : 173890.pdf (Publisher’s version ) (Closed access) Detailed neurobehavioural profiles are of major value for specific clinical management, but have remained underexposed in the population with intellectual disabilities (ID). This was traditionally classified based on IQ level only. Rapid advances in genetics enable etiology based stratification in the majority of patients, which reduces clinical heterogeneity. This paper illustrates that specific profiles can be obtained for rare syndromes with ID. Our main aim was to study (mal)adaptive functioning in Kleefstra Syndrome (KS) by comparing and contrasting our findings to three other subgroups: Koolen-de Vries Syndrome, GATAD2B-related syndrome, and a mixed control group of individuals with ID. In total, we studied 58 individuals (28 males, 30 females) with ID; 24 were diagnosed with KS, 13 with Koolen-de Vries Syndrome, 6 with the GATAD2B-related syndrome, and 15 individuals with undefined neurodevelopmental disorders. All individuals were examined with a Vineland Adaptive Behavior Scale, mini PAS-ADD interview, and an Autism Diagnostic Observation Schedule to obtain measures of adaptive and maladaptive functioning. Each of the three distinctive genetic disorders showed its own specific profile of adaptive and maladaptive functioning, while being contrasted mutually. However, when data of the subgroups altogether are contrasted to the data of KS, such differences could not be demonstrated. Based on our findings, specific management recommendations were discussed for each of the three syndromes. It is strongly suggested to consider the genetic origin in individuals with congenital neurodevelopmental disorders for individual based psychiatric and behavioral management. 10 p.

Contains fulltext : 175261.pdf (Publisher’s version ) (Open Access) Goal-directed behavior in a complex world requires the maintenance of goal-relevant information despite multiple sources of distraction. However, the brain mechanisms underlying distractor-resistant working or STM are not fully understood. Although early single-unit recordings in monkeys and fMRI studies in humans pointed to an involvement of lateral prefrontal cortices, more recent studies highlighted the importance of posterior cortices for the active maintenance of visual information also in the presence of distraction. Here, we used a DMS task and multivariate searchlight analyses of fMRI data to investigate STM maintenance across three extended delay phases. Participants maintained two samples (either faces or houses) across an unfilled pre-distractor delay, a distractor-filled delay, and an unfilled post-distractor delay. STM contents (faces vs. houses) could be decoded above-chance in all three delay phases from occipital, temporal, and posterior parietal areas. Classifiers trained to distinguish face versus house maintenance successfully generalized from pre- to post-distraction delays and vice versa, but not to the distractor delay period. Furthermore, classifier performance in all delay phases was correlated with behavioral performance in house, but not face, trials. Our results demonstrate the involvement of distributed posterior, but not lateral prefrontal, cortices in active maintenance during and after distraction. They also show that the neural code underlying STM maintenance is transiently changed in the presence of distractors and reinstated after distraction. The correlation with behavior suggests that active STM maintenance is particularly relevant in house trials, whereas face trials might rely more strongly on contributions from long-term memory. 19 p.

Item does not contain fulltext The aim of this study was to evaluate the effectiveness of a computer-based executive function (EF) training in children with specific language impairment (SLI). Ten children with SLI, ages 8 to 12 years, completed a 25-session training of visuospatial working memory, inhibition and cognitive flexibility over a 6-week period. Treatment outcome was examined directly after training and at 6 months follow-up by tasks of the three trained EF, tasks of untrained neurocognitive functions (verbal working memory, attention, planning and fluency), and ratings of EF and behavioral problems by parents and teachers. Directly after training, results showed significant improvement on cognitive flexibility and a positive trend for visuospatial storage and inhibition. At 6 months follow-up, the children performed significantly better on tasks of all three trained EFs. Furthermore, the results showed significant improvement on sustained attention, attention control, parent- and teacher-rated attention behavior and parent-rated EF and externalizing behavior with medium effect sizes. The results of this pilot study highlight the importance of a large-scale, randomized controlled trial examining the possible effects of EF training in children with SLI. 20 p.

Item does not contain fulltext Previous studies have suggested that alterations in excitatory/inhibitory neurotransmitters might play a crucial role in autism spectrum disorder (ASD). Proton magnetic resonance spectroscopy (1H-MRS) can provide valuable information about abnormal brain metabolism and neurotransmitter concentrations. However, few 1H-MRS studies have been published on the imbalance of the two most abundant neurotransmitters in ASD: glutamate (Glu) and gamma-aminobutyric acid (GABA). Moreover, to our knowledge none of these published studies is performed with a study population consisting purely of high-functioning autism (HFA) adolescents. Selecting only individuals with HFA eliminates factors possibly related to intellectual impairment instead of ASD. This study aims to assess Glu and GABA neurotransmitter concentrations in HFA. Occipital concentrations of Glu and GABA plus macromolecules (GABA+) were obtained using 1H-MRS relative to creatine (Cr) in adolescents with HFA (n=15 and n=13 respectively) and a healthy control group (n=17). Multiple linear regression revealed significantly higher Glu/Cr and lower GABA+/Glu concentrations in the HFA group compared to the controls. These results imply that imbalanced neurotransmitter levels of excitation and inhibition are associated with HFA in adolescents. 6 p.

Contains fulltext : 176068.pdf (Publisher’s version ) (Open Access) BACKGROUND: Subjective memory complaints (SMC) are common among older adults, but it is unclear to what extent adults with SMC spontaneously use memory strategies to compensate for their memory problems. As SMC may be a risk factor for memory decline later, it is important to extend our knowledge about spontaneous compensatory mechanisms in older adults with SMC. METHOD: Self-reported strategy use and observed strategy use were assessed in 38 adults with and 38 without SMC. RESULTS: Adults with SMC used more strategies in daily life than those without. In the SMC group, memory complaints were positively correlated with strategy use. Only in adults without SMC, a significant correlation was found between observed strategy use and task performance. CONCLUSION: Strategy use in older adults with SMC may be compensatory in nature, but did not increase their objective memory performance. Therefore, older adults with SMC might benefit from interventions aimed at optimizing strategy use. 5 p.

Contains fulltext : 177926.pdf (Publisher’s version ) (Open Access) Despite long-term successful treatment with cART, impairments in cognitive functioning are still being reported in HIV-infected patients. Since changes in cognitive function may be preceded by subtle changes in brain function, neuroimaging techniques, such as resting-state functional magnetic resonance imaging (rs-fMRI) have become useful tools in assessing HIV-associated abnormalities in the brain. The purpose of the current study was to examine the extent to which HIV infection in virologically suppressed patients is associated with disruptions in subcortical regions of the brain in comparison to a matched HIV-negative control group. The sample consisted of 72 patients and 39 controls included between January 2012 and January 2014. Resting state functional connectivity was determined between fourteen regions-of-interest (ROI): the left and right nucleus accumbens, amygdala, caudate nucleus, hippocampus, putamen, pallidum and thalamus. A Bayesian method was used to estimate resting-state functional connectivity, quantified in terms of partial correlations. Both groups showed the strongest partial correlations between the left and right caudate nucleus and the left and right thalamus. However, no differences between the HIV patients and controls were found between the posterior expected network densities (control network density = 0.26, SD = 0.05, patient network density = 0.26, SD = 0.04, p = 0.58). The results of the current study show that HIV does not affect subcortical connectivity in virologically controlled patients who are otherwise healthy. 6 p.

Contains fulltext : 2066_160347-20180426090935-8018889645ae17b2f7a3fc8.83875609.pdf (Publisher’s version ) (Open Access) Language is classically thought to be supported by perisylvian cortical regions. Here we provide intracranial evidence linking the hippocampal complex to linguistic processing. We used direct recordings from the hippocampal structures to investigate whether theta oscillations, pivotal in memory function, track the amount of contextual linguistic information provided in sentences. Twelve participants heard sentences that were either constrained ("She locked the door with the") or unconstrained ("She walked in here with the") before presentation of the final word ("key"), shown as a picture that participants had to name. Hippocampal theta power increased for constrained relative to unconstrained contexts during sentence processing, preceding picture presentation. Our study implicates hippocampal theta oscillations in a language task using natural language associations that do not require memorization. These findings reveal that the hippocampal complex contributes to language in an active fashion, relating incoming words to stored semantic knowledge, a necessary process in the generation of sentence meaning. 6 p.

Contains fulltext : 162129.pdf (Publisher’s version ) (Open Access) Ruminations are repetitive thoughts associated with symptoms, causes, and consequences of one's negative feelings. The objective of this study was to explore the neuronal basis of depressive rumination in a non-clinical population within the context of emotional control. Participants scoring high or low on the tendency to ruminate scale took part in the EEG experiment. Their EEG data were collected during a state of induced depressive ruminations and compared with positive and neutral conditions. We hypothesized that both groups would differ according to the level of activation and effective connectivity among the structures involved in the emotional control circuit. Clustering of independent components, together with effective connectivity (Directed Transfer Function), was performed using the EEG signal. The main findings involved decreased activation of the left dorsolateral prefrontal cortex (DLPFC) and increased activation of the left temporal lobe structures in the highly ruminating group. The latter result was most pronounced during the ruminative condition. Decreased information from the left DLPFC to the left temporal lobe structures was also found, leading to the conclusion that hypoactivation of the left DLPFC and its inability to modulate the activation of the left temporal lobe structures is crucial for the ruminative tendencies. 15 p.

Item does not contain fulltext Visuospatial neglect is a disabling syndrome resulting in impaired activities of daily living and in longer durations of inpatient rehabilitation. Effective interventions to remediate neglect are still needed. The combination of tDCS and an optokinetic task might qualify as a treatment method. A total of 32 post-acute patients with left (n = 20) or right-sided neglect were allotted to an intervention or a control group (both groups n = 16). The intervention group received eight sessions of 1.5-2.0 mA parietal transcranial direct current stimulation (tDCS) during the performance of an optokinetic task distributed over two weeks. Additionally they received standard therapy for five hours per day. The control group received only the standard therapy. Patients were examined twice before (with 3-4 days between examinations) and twice after treatment (5-6 days between examinations). Compared to the control group and controlling for spontaneous remission, the intervention group improved on spontaneous body orientation and the Clock Drawing Test. Intragroup comparisons showed broad improvements on egocentric but not on allocentric symptoms only for the intervention group. A short additional application of tDCS during an optokinetic task led to improvements of severe neglect compared to a standard neurological early rehabilitation treatment. Improvements seem to concern primarily egocentric rather than allocentric neglect. 12 p.

The ability to form associations between a multitude of events is the hallmark of episodic memory. Computational models have espoused the importance of the hippocampus as convergence zone, binding different aspects of an episode into a coherent representation, by integrating information from multiple brain regions. However, evidence for this long-held hypothesis is limited, since previous work has largely focused on representational and network properties of the hippocampus in isolation. Here we identify the hippocampus as mnemonic convergence zone, using a combination of multivariate pattern and graph-theoretical network analyses of functional magnetic resonance imaging data from humans performing an associative memory task. We observe overlap of conjunctive coding and hub-like network attributes in the hippocampus. These results provide evidence for mnemonic convergence in the hippocampus, underlying the integration of distributed information into episodic memory representations., The ability to form associations between events is the hallmark of episodic memory and is thought to involve the hippocampus. Here the authors use a combination of multivariate pattern and graph theoretical network analyses of functional imaging data in humans, and show conjunctive coding and hub-like network attributes in the hippocampus.

We demonstrate distinct α- (7–14 Hz) and β-band (15–30 Hz) rhythms in rat somatosensory cortex in vivo using epidural electrocorticography recordings. Moreover, we show in rats that a genuine β-rhythm coexists alongside β-activity that reflects the second harmonic of the arch-shaped somatosensory α-rhythm. This demonstration of a genuine somatosensory β-rhythm depends on a novel quantification of neuronal oscillations that is based on their rhythmic nature: lagged coherence. Using lagged coherence, we provide two lines of evidence that this somatosensory β-rhythm is distinct from the second harmonic of the arch-shaped α-rhythm. The first is based on the rhythms' spatial properties: the α- and β-rhythms are demonstrated to have significantly different topographies. The second is based on the rhythms' temporal properties: the lagged phase-phase coupling between the α- and β-rhythms is demonstrated to be significantly less than would be expected if both reflected a single underlying nonsinusoidal rhythm. Finally, we demonstrate that 1) the lagged coherence spectrum is consistent between signals from rat and human somatosensory cortex; and 2) a tactile stimulus has the same effect on the somatosensory α- and β-rhythms in both rats and humans, namely suppressing them. Thus we not only provide evidence for the existence of genuine α- and β-rhythms in rat somatosensory cortex, but also for their homology to the primate sensorimotor α- and β-rhythms.

Contains fulltext : 167975.pdf (Publisher’s version ) (Open Access) Working memory (WM) tasks may involve brain activation actually implicated in long-term memory (LTM). In order to disentangle these two memory systems, we employed a combined WM/LTM task, using a spatial relational (object-location) memory paradigm and analyzed which brain areas were associated with successful performance for either task using fMRI. Critically, we corrected for the performance on the respective memory task when analyzing subsequent memory effects. The WM task consisted of a delayed-match-to-sample task assessed in an MRI scanner. Each trial consisted of an indoor or outdoor scene in which the exact configuration of four objects had to be remembered. After a short delay (7-13 s), the scene was presented from a different angle and spatial recognition for two objects was tested. After scanning, participants received an unexpected subsequent recognition memory (LTM) task, where the two previously unprobed objects were tested. Brain activity during encoding, delay phase and probe phase was analyzed based on WM and LTM performance. Results showed that successful WM performance, when corrected for LTM performance, was associated with greater activation in the inferior frontal gyrus and left fusiform gyrus during the early stage of the maintenance phase. A correct decision during the WM probe was accompanied by greater activation in a wide network, including bilateral hippocampus, right superior parietal gyrus and bilateral insula. No voxels exhibited supra-threshold activity during the encoding phase, and we did not find any differential activity for correct versus incorrect trials in the WM task when comparing LTM correct versus LTM incorrect trials. 11 p.

Contains fulltext : 165799.pdf (Publisher’s version ) (Open Access) Parkinson's resting tremor has been linked to pathophysiological changes both in the basal ganglia and in a cerebello-thalamo-cortical motor loop, but the role of those circuits in initiating and maintaining tremor remains unclear. Here, we test whether and how the cerebello-thalamo-cortical loop is driven into a tremor-related state by virtue of its connectivity with the basal ganglia. An internal replication design on two independent cohorts of tremor-dominant Parkinson patients sampled brain activity and tremor with concurrent EMG-fMRI. Using dynamic causal modeling, we tested: (1) whether activity at the onset of tremor episodes drives tremulous network activity through the basal ganglia or the cerebello-thalamo-cortical loop and (2) whether the basal ganglia influence the cerebello-thalamo-cortical loop through connectivity with the cerebellum or motor cortex. We compared five physiologically plausible circuits, model families in which transient activity at the onset of tremor episodes (assessed using EMG) drove network activity through the internal globus pallidus (GPi), external globus pallidus, motor cortex, thalamus, or cerebellum. In each family, we compared two models in which the basal ganglia and cerebello-thalamo-cortical loop were connected through the cerebellum or motor cortex. In both cohorts, cerebral activity associated with changes in tremor amplitude (using peripheral EMG measures as a proxy for tremor-related neuronal activity) drove network activity through the GPi, which effectively influenced the cerebello-thalamo-cortical loop through the motor cortex. We conclude that cerebral activity related to Parkinson's tremor first arises in the GPi and is then propagated to the cerebello-thalamo-cortical circuit. SIGNIFICANCE STATEMENT: Parkinson's resting tremor has been linked to pathophysiological changes both in the basal ganglia and in a cerebello-thalamo-cortical motor loop, but the role of those circuits in initiating and maintaining tremor remains unclear. Using dynamic causal modeling of concurrently collected EMG-fMRI data in two cohorts of Parkinson's patients, we showed that cerebral activity associated with changes in tremor amplitude drives network activity through the basal ganglia. Furthermore, the basal ganglia effectively influenced the cerebello-thalamo-cortical circuit through the motor cortex (but not the cerebellum). Out findings suggest that Parkinson's tremor-related activity first arises in the basal ganglia and is then propagated to the cerebello-thalamo-cortical circuit. 11 p.

Contains fulltext : 167606.pdf (Publisher’s version ) (Open Access) Deletions of the 15q26 region encompassing the chromodomain helicase DNA binding domain 2 (CHD2) gene have been associated with intellectual disability, behavioral problems, and several types of epilepsy. Including the cases mentioned in ECARUCA (European cytogeneticists association register of unbalanced chromosome aberrations) and DECIPHER (database of genomic variation and phenotype in humans using ensembl resources), so far, a total of 13 intellectually disabled patients with a genetically proven deletion of the CHD2 gene are described, of whom eleven had a history of severe forms of epilepsy starting from a young age. In this article, a moderately intellectually disabled 15-year-old male with a 15q26.1-q26.2 interstitial deletion is reported, who was referred for analysis of two recent short-lasting psychotic episodes that were nonresponsive to antipsychotic treatment and recurrent disinhibited behaviors since early infancy. Careful interdisciplinary assessment revealed that the psychotic phenomena originated from a previously unrecognized absence epilepsy. Treatment with valproic acid was started which resulted in full remission of psychotic symptoms, and consequently, substantial improvement of behavior. It was concluded that in case of (rare) developmental disorders with genetically proven etiology, a detailed inventory of anamnestic data and description of symptomatology over time may elucidate epilepsy-related psychopathology for which a specific treatment regimen is needed. 5 p.

Contains fulltext : 167882.pdf (Publisher’s version ) (Closed access) INTRODUCTION: Recognition and visual working memory tasks from the Wechsler Memory Scale-Fourth Edition (WMS-IV) have previously been documented as useful indicators for suboptimal performance. The present study examined the clinical utility of the Dutch version of the WMS-IV (WMS-IV-NL) for the identification of suboptimal performance using an analogue study design. METHOD: The patient group consisted of 59 mixed-etiology patients; the experimental malingerers were 50 healthy individuals who were asked to simulate cognitive impairment as a result of a traumatic brain injury; the last group consisted of 50 healthy controls who were instructed to put forth full effort. RESULTS: Experimental malingerers performed significantly lower on all WMS-IV-NL tasks than did the patients and healthy controls. A binary logistic regression analysis was performed on the experimental malingerers and the patients. The first model contained the visual working memory subtests (Spatial Addition and Symbol Span) and the recognition tasks of the following subtests: Logical Memory, Verbal Paired Associates, Designs, Visual Reproduction. The results showed an overall classification rate of 78.4%, and only Spatial Addition explained a significant amount of variation (p < .001). Subsequent logistic regression analysis and receiver operating characteristic (ROC) analysis supported the discriminatory power of the subtest Spatial Addition. A scaled score cutoff of

Contains fulltext : 166181.pdf (Publisher’s version ) (Open Access) 5 p.

Contains fulltext : 169503.pdf (Publisher’s version ) (Open Access) Studies on prospective memory (PM) development in adolescents point to age-related increases through to adulthood. The goal of the present study was to examine whether instructing adolescents to engage in an episodic prospection of themselves executing future actions (i.e., future thinking) when forming an intention would improve their PM performance and reduce age-related differences. Further, we set out to explore whether future thinking instructions result in stronger memory traces and/or stronger cue?context associations by evaluating retrospective memory for the PM cues after task completion and monitoring costs during PM task processing. Adolescents and young adults were allocated to either the future thinking, repeated-encoding or standard condition. As expected, adolescents had fewer correct PM responses than young adults. Across age groups, PM performance in the standard condition was lower than in the other encoding conditions. Importantly, the results indicate a significant interaction of age by encoding condition. While adolescents benefited most from future thinking instructions, young adults performed best in the repeated-encoding condition. The results also indicate that the beneficial effects of future thinking may result from deeper intention-encoding through the simulation of future task performance. 18 p.

The ability to temporarily store and manipulate information in working memory is a hallmark of human intelligence and differs considerably across individuals, but the structural brain correlates underlying these differences in working memory capacity (WMC) are only poorly understood. In two separate studies, diffusion MRI data and WMC scores were collected for 70 and 109 healthy individuals. Using a combination of probabilistic tractography and network analysis of the white matter tracts, we examined whether structural brain network properties were predictive of individual WMC. Converging evidence from both studies showed that lateral prefrontal cortex and posterior parietal cortex of high-capacity individuals are more densely connected compared with low-capacity individuals. Importantly, our network approach was further able to dissociate putative functional roles associated with two different pathways connecting frontal and parietal regions: a corticocortical pathway and a subcortical pathway. In Study 1, where participants were required to maintain and update working memory items, the connectivity of the direct and indirect pathway was predictive of WMC. In contrast, in Study 2, where participants were required to maintain working memory items without updating, only the connectivity of the direct pathway was predictive of individual WMC. Our results suggest an important dissociation in the circuitry connecting frontal and parietal regions, where direct frontoparietal connections might support storage and maintenance, whereas subcortically mediated connections support the flexible updating of working memory content.SIGNIFICANCE STATEMENTUsing diffusion MRI and network analysis, we found that the capacity of healthy individuals to temporally maintain information in working memory was related to a cortical pathway connecting frontal and parietal regions. The updating of working memory content, on the other hand, additionally involved a subcortical pathway connecting frontal and parietal regions via thalamus and basal ganglia. These results suggest that the two anatomical pathways serve different functional roles for working memory.