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Interference Task (interference + task)
Selected Abstracts,Prefrontal' cognitive performance of healthy subjects positively correlates with cerebral FDOPA influx: An exploratory [18F]-fluoro-L-DOPA-PET investigationHUMAN BRAIN MAPPING, Issue 10 2007Ingo Vernaleken Abstract Dopamine neurotransmission influences those cognitive processes, which are generally regarded as prefrontal cortical functions. In previous positron-emission-tomography (PET) studies, net blood-brain clearance of [18F]-fluoro-l-DOPA (FDOPA) correlated with impaired cognitive performance in patients with Parkinson's disease or schizophrenia. We hypothesized that FDOPA influx also correlates with performance of cognitive tasks associated with prefrontal functioning in healthy volunteers. The net blood-brain clearance of FDOPA (K) was mapped in a group of 11 healthy volunteers and calculated in striatal volumes-of-interest. The Wisconsin-Card-Sorting-Test (WCST), Stroop-Test, Trail-Making-Test (TMT-A/B), and Continuous-Performance-Test (CPT-M) had been administered previously to the same subjects. No correlation of K with perseverative errors in WCST or age could be found. However, there were significant positive correlations between the magnitude of K in caudate nucleus, putamen, and midbrain with performance of the TMT-B, CPT-M, and the Stroop test. Highest correlations were found between the time needed to perform the Stroop interference task and the K of striatal areas (Caudate nucleus: ,0.780, P = 0.005; putamen: ,0.870, P < 0. 001). Thus, the present findings reveal a strong correlation between dopamine synthesis capacity in striatum of healthy volunteers and performance of cognitive tasks linked to the prefrontal cortex. Hum Brain Mapp 2006. © 2006 Wiley-Liss, Inc. [source] A developmental fMRI study of self-regulatory controlHUMAN BRAIN MAPPING, Issue 11 2006Rachel Marsh Abstract We used functional magnetic resonance imaging (fMRI) to investigate the neural correlates of self-regulatory control across development in healthy individuals performing the Stroop interference task. Proper performance of the task requires the engagement of self-regulatory control to inhibit an automatized response (reading) in favor of another, less automatic response (color naming). Functional MRI scans were acquired from a sample of 70 healthy individuals ranging in age from 7 to 57 years. We measured task-related regional signal changes across the entire cerebrum and conducted correlation analyses to assess the associations of signal activation with age and with behavioral performance. The magnitude of fMRI signal change increased with age in the right inferolateral prefrontal cortex (Brodmann area [BA] 44/45) and right lenticular nucleus. Greater activation of the right inferolateral prefrontal cortex also accompanied better performance. Activity in the right frontostriatal systems increased with age and with better response inhibition, consistent with the known functions of frontostriatal circuits in self-regulatory control. Age-related deactivations in the mesial prefrontal cortex (BA 10), subgenual anterior cingulate cortex (BA 24), and posterior cingulate cortex (BA 31) likely represented the greater engagement of adults in self-monitoring and free associative thought processes during the easier baseline task, consistent with the improved performance on this task in adults compared with children. Although we cannot exclude the possibility that age-related changes in reading ability or in the strategies used to optimize task performance were responsible for our findings, the correlations of brain activation with performance suggest that changes in frontostriatal activity with age underlie the improvement in self-regulatory control that characterizes normal human development. Hum Brain Mapp, 2006. © 2006 Wiley-Liss, Inc. [source] Meta-analysis of functional imaging data using replicator dynamicsHUMAN BRAIN MAPPING, Issue 1 2005Jane Neumann Abstract Despite the rapidly growing number of meta-analyses in functional neuroimaging, the field lacks formal mathematical tools for the quantitative and qualitative evaluation of meta-analytic data. We propose to use replicator dynamics in the meta-analysis of functional imaging data to address an important aspect of neuroimaging research, the search for functional networks of cortical areas that underlie a specific cognitive task. The replicator process requires as input only a list of activation locations, and it results in a network of locations that jointly show significant activation in most studies included in the meta-analysis. These locations are likely to play a critical role in solving the investigated cognitive task. Our method was applied to a meta-analysis of the Stroop interference task using data provided by the publicly accessible database BrainMap DBJ. Hum Brain Mapp 25:165,173, 2005. © 2005 Wiley-Liss, Inc. [source] The effects of acute exercise on cognitive functioning and cigarette cravings during temporary abstinence from smokingHUMAN PSYCHOPHARMACOLOGY: CLINICAL AND EXPERIMENTAL, Issue 3 2008Kate Janse Van Rensburg Abstract Background Abstinence from smoking is associated with increased cravings, risk of accidents and self-reported poor concentration. A single exercise session can reduce cravings and self-reported poor concentration and can enhance cognitive performance among non-smokers. Objective To assess whether acute exercise impacts on the cognitive performance and cravings of abstaining smokers. Methods In a counterbalanced cross-over design, participants (n,=,23) did a 15,min passive or exercise condition, following cigarette abstinence. Cognitive functioning was measured by a computerised version of the Stroop colour-word interference task. Cravings were measured using the 10-item, 2-factor QSU-Brief and a single item for ,desire to smoke'. Measures were recorded at baseline, immediately post, 5, 10 and 15-min post treatment. Results A 2-way ANOVA showed no significant condition,×,time interaction for cognitive functioning. Significant interaction effects were found for desire to smoke, QSU Factor 1 (desire,behave) and 2 (desire,affect). Exercise reduced cravings for up to 15,min post treatment. Discussion Findings support previous research that acute exercise reduces cravings to smoke. Future research should determine if exercise can enhance other objective aspects of cognitive performance, and repeat the present study with a more homogeneous sample, in terms of Stroop performance. Conclusion This is the first study to show that exercise can reduce both factors of the QSU-Brief, but effects on cognitive functioning were not observed. Copyright © 2008 John Wiley & Sons, Ltd. [source] The influence of folate serum levels on depressive mood and mental processing in patients with epilepsy treated with enzyme-inducing anti-epileptic drugsACTA NEUROPSYCHIATRICA, Issue 2 2003J. Rösche Background: Folate deficiency is common in patients with epilepsy and also occurs in patients with depression or cognitive deficits. Objective: This study investigates whether low serum folate levels may contribute to depressive mood and difficulties in mental processing in patients with epilepsy treated with anti-epileptic drugs inducing the cytochrome P450. Methods: We analysed the serum folate levels, the score in the Self Rating Depression Scale (SDS) and the results of a bedside test in mental processing in 54 patients with epilepsy. Results: There was a significant negative correlation between the serum folate levels and the score in SDS and significant positive correlations between the score in SDS and the time needed to process an interference task or a letter-reading task. Conclusions: Low serum folate levels may contribute to depressive mood and therefore to difficulties in mental processing. Further studies utilizing total plasma homocysteine as a sensitive measure of functional folate deficiency and more elaborate tests of mental processing are required to elucidate the impact of folate metabolism on depressive mood and cognitive function in patients with epilepsy. [source] | ||||||||||