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Query: EC:2.3.1.21 (CPT)
4,580 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Vigilance deficits have been found in both schizophrenic and ADHD subjects. The two patient groups have never been directly compared on any vigilance measure, however. In the present study 20 early-onset schizophrenics were compared to 20 ADHD adolescents on a Degraded Stimulus Continuous Performance Test (DS-CPT). A comparison group of 30 normal adolescents was also included. Results showed no significant differences between the three groups on any of the DS-CPT measures. Different hypotheses are put forth to explain the findings, among them that the task may be insensitive to identifying sustained attention deficits in adolescent populations.
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PMID:No vigilance deficit found in either young schizophrenic or ADHD subjects. 967 63

Clinic-referred teens (ages 12-19) with ADHD and ODD (N = 101) were compared to community control (CC) teens, equated for age and sex, (N = 39) on a variety of psychological tasks assessing executive functioning (EF), temporal reward discounting, and time estimation and reproduction. A factor analysis reduced the EF measures to three dimensions, representing CPF Inattention, Working Memory, and CPT Inhibition. Results indicated that the ADHD group had significantly more CPT Inattention than the CC group. No differences were found for Working Memory or CPT Inhibition. The ADHD group displayed significantly greater temporal discounting of delayed hypothetical monetary rewards relative to immediate ones and manifested more impaired time reproduction, but not time estimation, than did the CC group. Main effects for level of IQ were found only on the Working Memory factor and largely did not interact with the group factor otherwise. The group differences in CPT Inattention, temporal discounting, and time reproduction were not a function of level of comorbid oppositional defiant disorder, delinquency, or anxiety-depression. Results are reasonably consistent with past research on EF and sense of time in children with ADHD and extend these findings to the adolescent age group. Problems with working memory and CPT inhibition found in prior studies of children with ADHD, however, were not evident here, perhaps owing to age-related improvements or insufficient task difficulty.
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PMID:Executive functioning, temporal discounting, and sense of time in adolescents with attention deficit hyperactivity disorder (ADHD) and oppositional defiant disorder (ODD). 1176 Dec 87

High density electrical mapping was used to index event-related brain activity in subjects performing parametric variations of the "AX"-type continuous performance task (AX-CPT) that differentially challenge control, and informative control conditions. In the AX-CPT, subjects must use context, created by a cue stimulus, to guide response to a target. Diseases such as schizophrenia and attention deficit hyperactivity disorder (ADHD) are associated with impaired AX-CPT performance. Event-related potentials (ERP) were analyzed as a function of both global and local stimulus context. The topographical analysis revealed that well-defined ERP are elicited under conditions where subjects must override a prepotent response. Activation patterns related to overriding a prepotent response (Go to No-Go) differed markedly from those associated with overriding a prepotent non-response (No-Go to Go). Dipole source mapping suggested that withholding a prepotent response is reflected primarily in anterior cingulate/dorsolateral prefrontal cortex activity during the 350-450 ms latency range following presentation of the No-Go. In contrast, preparing to respond is reflected in parietal (including area BA 40) activity during the same latency range, followed by a prolonged frontal negativity (contingent negative variation; CNV). Similar patterns of activation were observed whether the changes in preparation were triggered by cue or target stimuli, though target-elicited potentials peaked earlier.
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PMID:Changing plans: a high density electrical mapping study of cortical control. 1281 85

Comparisons of two assessment measures for ADHD: the ADHD Behavior Checklist and the Integrated Visual and Auditory Continuous Performance Test (IVA CPT) were examined using undergraduates (n=44) randomly assigned to a control or a simulated malingerer condition and undergraduates with a valid diagnosis of ADHD (n=16). It was predicted that malingerers would successfully fake ADHD on the rating scale but not on the CPT for which they would overcompensate, scoring lower than all other groups. Analyses indicated that the ADHD Behavior Rating Scale was successfully faked for childhood and current symptoms. IVA CPT could not be faked on 81% of its scales. The CPT's impairment index results revealed: sensitivity 94%, specificity 91%, PPP 88%, NPP 95%. Results provide support for the inclusion of a CPT in assessment of adult ADHD.
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PMID:Detection of malingering in assessment of adult ADHD. 1459 53

Poor performance on tests of reading comprehension could be the result of weak word-recognition skills, inconsistent attention (ADD), or a combination of the two. Identifying the source of the reading disability (RD) reliably has been difficult because inconsistent attention interferes with reading and weak word recognition skill makes attention wander. The situation is further complicated by the fact that there are no objective diagnostic tests for ADD (Breggin, 1998; Diller, 1998). We proposed a new model of differential diagnosis of ADHD-I/RD and field-tested its utility in two studies. The new diagnostic procedure utilizes intra-individual differences seen in the performance of at-risk learners on tasks related to reading that vary in the degree of sustained attention required for successful performance. The hypothesis is that children whose attention is inconsistent would perform more poorly on tests such as listening comprehension, which require sustained attention, than on tests such as reading comprehension, which are more tolerant of inattention. Such differences will not be seen in the test scores of children who have only a reading disability because their performance on reading tests is determined more by the difficulty level of the tests than by the sensitivity of the tests to attention. The validity of this new model was evaluated by determining the relationship between differences seen in the scores of tests that differ in their attention requirement and the degree of inconsistency in sustained attention as measured by Conners' CPT. The results of the two studies indicate this to be a viable approach. The results of the second study are presented in this report.
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PMID:A cognitive tool to diagnose predominantly inattentive ADHD behavior. 1526 Jan 70

This study used a double-dissociation design to evaluate whether children with ADHD demonstrated specific deficits relative to children with Reading Disorders. Recent theory suggests that ADHD children have deficits in time perception and working memory, whereas RD children have deficits in phonological decoding. The performance of 113 clinic-referred children aged 6-11 was examined using measures of working memory, phonological processing, and time perception. Respondents completed two time production tasks in which they were to judge when 30-s had elapsed, and another in which they were asked to estimate the duration of the Conners' CPT (CCPT). Time Perception and phonological processing variables were submitted to a 2 x 2 ANCOVA (ADHD vs. RD), covarying for age, SES, IQ, and working memory. Children with ADHD were more likely to overestimate the time taken for the CCPT than children without ADHD, but no group differences were found on the 30-s estimation tasks. Children with RD did not display deficits in time estimation, but showed deficits in auditory phonological processing. The lack of interaction effects supported an "etiological subtype" over the "phenocopy" model of ADHD and RD. No group differences were detected using the CCPT. Although our previous studies did not find an order effect for the Conners' CPT in a 1-hr battery, a fatigue effect was evident with a 1.5-hr battery. The implications for Barkley's behavioral inhibition theories (R. Barkley, 1997) are discussed.
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PMID:Time perception: does it distinguish ADHD and RD children in a clinical sample? 1550 28

Starting from a discussion of the validity of neuropsychological methods for the diagnosis of ADHD the results of an own study are presented. What is the diagnostic value of the German version of the CPT (Continuous Performance Task) and the DAT (Dortmunder Aufmerksamkeitstest) in discriminating ADHD subtypes (according to DSM-IV) and in which areas do the children of each subtype differ from a control group of normal children? The computer versions of the CPT and DAT were administered to 14 boys with the "combined subtype" of ADHD, 14 boys with the "predominantly inattentive type" of ADHD and 18 boys without clinical signs; all groups were matched in age and intelligence. Subsequently the mean differences between the various test parameters were assessed as to their significance. Contrary to other studies there were no significant differences either between both ADHS types or relative to the control group with regard to the CPT omission errors and the reaction time. There were differences in the reaction variability both between the ADHD subtypes and relative to the control group. Only the "combined subtype", not the "pre-dominantly inattentive type" differed from the control group as to the CPT commission errors. Regarding the DAT, there were significant differences between all three groups regarding both the solution quality and the response delay.
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PMID:[Neuropsychological assessment of ADHD subtypes]. 1585 Jan 63

Smoking is highly prevalent among patients with Attention Deficit Hyperactivity Disorder (ADHD). Previous studies using the reversed continuous performance task (R-CPT) have suggested that nicotine reduces inattention. Since especially adults with ADHD have been claimed to suffer from a core deficit in inhibitory control, this study aimed at determining whether nicotine improves response inhibition in addition to attention. Sixteen healthy regular smokers participated in a pre/post treatment design in which transdermal patches containing 7 and 21 mg nicotine per day were administered in a counterbalanced, double-blind manner. In a second study, patches containing 0 mg (placebo) and 21 mg per day were administered to a different group of regular smokers. For replication purposes, the R-CPT and the profile of mood states (POMS) were administered. Furthermore, a different version of the continuous performance task (CPT-AX) and the stop-signal task, traditionally used to measure response inhibition, were presented. The high dose of nicotine was found to relieve self-reported Depression in Study 1 and Fatigue in Study 2. Performance data indicated acute effects of nicotine on attention-related, but not on inhibition-related measures. Especially the comparison with placebo revealed decreases in reaction time and variability of responding. The results imply that patients with ADHD smoke to reduce inattention.
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PMID:Acute effects of nicotine on attention and response inhibition. 1636 Aug 13

The present study was designed to examine the association of Rolandic spikes with the neuropsychological profile of children with ADHD. A total of 48 children (mean age 9.4 +/- 1.6 years, range 6.7-14.9 years; 16 ADHD children with Rolandic spikes, 16 ADHD children without epileptiform discharges and 16 healthy controls) matched for age, gender, and IQ were examined with a neuropsychological assessment battery focussing on attentional processing, cognitive efficiency, response inhibition, visuospatial and auditory-verbal short-term memory and language function (CPT-AX, Stroop, digit span, Complex Figure of Rey, Heidelberg Language Development Test). ADHD children with Rolandic spikes performed worse than ADHD children without epileptiform discharges and healthy controls in a variety of CPT and Stroop test measures. In particular, they made significantly more commission errors, reflecting impaired inhibition of an ongoing response. In addition, they had pronounced difficulties in the color word condition of the Stroop test and exhibited lower interference scores, indicating poorer interference control. Results of this pilot study suggest that in some ADHD children Rolandic spikes or an associated dysfunction aggravate the course of ADHD and predispose to increased impulsivity, evidenced in deficient inhibition of an ongoing response, and decreased interference control.
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PMID:Rolandic spikes increase impulsivity in ADHD - a neuropsychological pilot study. 1675 38

Attentional impairments in children occur in the context of both developmental and acquired disorders involving the central nervous system (CNS) and may have implications for ongoing development, potentially impeding cognitive, educational, and behavioral functions. Using a continuous performance paradigm (CPT), this study compared attentional profiles of children with developmental and acquired conditions impacting on the CNS: (i) attention deficit-hyperactivity disorder (ADHD: n=27); (ii) moderate traumatic brain injury (TBI: n=41); (iii) acute lymphoblastic leukemia (n=31); and (iv) insulin-dependent diabetes mellitus (n=39). A healthy control group (n=46) was also examined. Groups were compared on measures of sustained attention, selective attention, and response inhibition. In addition, measures of performance variability and deterioration and processing speed were examined. Results showed that children with ADHD exhibited global and severe attentional impairments in contrast to all other groups. Children with moderate TBI displayed mild attentional difficulties, restricted to selective and sustained attention domains. In conclusion, although CPT parameters differentiated the ADHD group from all others, a disorder-specific profile was not observed.
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PMID:Comparing attentional skills in children with acquired and developmental central nervous system disorders. 1698 4


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