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Executive Processes (executive + process)
Selected AbstractsWorking memory in posttraumatic stress disorder,an event-related potential studyJOURNAL OF TRAUMATIC STRESS, Issue 2 2001Cherrie Galletly Abstract This study examined ERP topography during the updating and the utilization of working memory in subjects with PTSD. Event-related potentials of 18 participants with PTSD and 18 controls were recorded from 32 scalp electrodes during an auditory target detection task requiring the constant updating of target identity. Midline N2 and P3 abnormalities previously noted in PTSD during target detection were replicated. Scalp topographic data revealed sustained reduction in activity over the right hemisphere during working memory updating. Executive processes were associated with brief but widespread right hemisphere reductions during the P3, followed by sustained, bilateral reduction frontally. This study identifies an abnormal pattern of cortical network function during both the updating and use of working memory in PTSD. [source] Anatomy of executive deficit following ruptured anterior communicating artery aneurysmEUROPEAN JOURNAL OF NEUROLOGY, Issue 5 2009O. Martinaud Background and purpose:, To evaluate behavioral and cognitive deficits following anterior communicating artery aneurysm rupture and determine critical lesion locations. Methods:, We investigated 74 patients with standardized cognitive tests and behavioral inventory. Two examiners rated MRI signal abnormalities in 51 predetermined regions of interest. Classification tree analysis was used to select regions associated with each cognitive deficit. Results:, Eleven patients presented behavioral executive deficits and 10 had cognitive executive deficit. Their presence depended on left hemisphere lesions only: (i) ventral striatum lesion was associated with behavioral executive deficit (P = 0.04), reduction of activities (P = 0.01), and hyperactivity (P = 0.02); (ii) superior frontal gyrus lesion, with cognitive executive deficit (P = 0.01), action initiation deficit (P = 0.02), and rule deduction deficit (P = 0.02); (iii) anterior half of centrum semiovale lesion, with Stroop inhibition deficit (P = 0.02); (iv) medial superior and middle frontal gyri lesions, with task coordination deficit (P = 0.01); and (v) middle frontal gyrus lesion, with words generation deficit (P = 0.02). Conclusion:, This study supports that (i) cognitive executive deficits depend mostly on lateral prefrontal lesions, (ii) with locations varying according to executive process, and (iii) behavioral executive deficits are mainly due to left ventral striatum lesion in post-aneurysmal damage. [source] Young children have difficulty ascribing true beliefsDEVELOPMENTAL SCIENCE, Issue 3 2005Kevin J. Riggs Using the format of a false belief task (Wimmer & Perner, 1983), we investigated the ability of 88 3- and 4-year-olds to ascribe a previously held true belief to a story protagonist. In an unexpected transfer task, children found true belief ascription as difficult as false belief ascription even though they could answer memory questions about story details. Results are discussed in relation to theoretical accounts of theory of mind development that stress the importance of understanding the falsity of belief, and those accounts that stress the importance of information or executive processes. [source] Acute neuropsychological effects of methylphenidate in stimulant drug-naïve boys with ADHD II , broader executive and non-executive domainsTHE JOURNAL OF CHILD PSYCHOLOGY AND PSYCHIATRY AND ALLIED DISCIPLINES, Issue 11 2006Sinéad M. Rhodes Background:, Accumulating evidence supports methylphenidate-induced enhancement of neuropsychological functioning in attention deficit hyperactivity disorder (ADHD). The present study was designed to investigate the acute effects of the psychostimulant drug, methylphenidate (MPH), on neuropsychological performance in stimulant naïve boys with ADHD. Methods:, Seventy-three drug-naïve boys (age 7,15) with ADHD (combined type) completed neuropsychological tasks from the CANTAB battery under randomised, placebo controlled, double-blind conditions following an acute challenge with either placebo (n = 24), .3 (n = 25) or .6 (n = 24) mg/kg oral MPH. Results:, MPH did not impair performance on any task. MPH (.6 mg/kg) lengthened response latencies on a task of Spatial Recognition, shortened response times on a Reaction Time task and restored performance on a Delayed Matching to Sample visual, non-working memory task. Contrary to predictions, MPH did not enhance performance on tasks with a prominent executive component, including Go/NoGo, Spatial Working Memory, Stockings of Cambridge and Attentional Set shifting tasks. Conclusions:, Acute administration of MPH to drug-naïve boys with ADHD did not impair neuropsychological performance. Acute MPH enhanced performance on some aspects of non-executive functioning. MPH-induced slowing of responding on a relatively complex Spatial Recognition memory task and quickened responding on a reaction time task requiring less cognitive resources suggests that MPH may act by improving self-regulatory ability. MPH may not exert its effects on neuropsychological functioning by enhancing executive processes. [source] Low- and high-level controlled processing in executive motor control tasks in 5,6-year-old children at risk of ADHDTHE JOURNAL OF CHILD PSYCHOLOGY AND PSYCHIATRY AND ALLIED DISCIPLINES, Issue 7 2003Ariane C. Kalff Background: The scant research on the characteristics of Attention-Deficit/Hyperactivity Disorder (ADHD) in kindergarten years curtails progress on early assessment of ADHD. Method: By screening a general population sample of 1317 five- to six-year-old children, four groups of children were selected. The performance of 30 children later diagnosed with ADHD was compared with 74 children later diagnosed with ,borderline ADHD' (children exhibiting all ADHD symptoms but without disruptions on two situations), 113 children later diagnosed with other psychopathology, and 126 healthy controls on computerised motor control tasks involving low- and high-level controlled processing. In addition, motor control was compared with movement speed. Results: The children at risk of ADHD were in general less accurate and more variable in their movements than the children with other psychopathology and healthy controls. Under conditions of high-level controlled processing, the children at risk of ADHD were disproportionately more inaccurate and had a more unstable performance with their preferred hand than the other children. In addition, linear effects were found, with the children at risk of ADHD having the worst performance, followed by the children with ,borderline ADHD', and then both groups of control children. No significant group differences were found in movement speed. Conclusions: The main findings are interpreted as evidence for a specific deficit in high-level controlled processing in young children at risk of ADHD, now found in a motor task, rather than a response task. Furthermore, the results support the notion that ADHD represents a dimensional trait. In addition, problems in movement control (the need to allocate attentional capacity) rather than problems in movement speed distinguish children at risk of ADHD from other children. The findings are interpreted as evidence that higher-order executive processes, such as self-control and self-regulation, are already affected early in the development of ADHD. [source] |