Post-exertion neurocognitive test failure among student-athletes following concussion.

OBJECTIVE: The purpose of the present study was to examine post-exertion (PE) neurocognitive performance among student-athletes following concussion who were asymptomatic and returned to baseline normal neurocognitive test levels at rest. This study examined the neurocognitive performance of a sub-set of student-athletes who 'failed' to perform at baseline levels of neurocognitive function, i.e. exhibited downward reliable change index (RCI) alterations following a moderate exertional protocol during recovery from concussion. METHOD: A retrospective records review was carried out of Immediate Post-concussion Assessment and Cognitive Testing (ImPACT) and neuropsychological consultation data among athletes with sports-related concussion from a network of 22 schools and one junior hockey programme. RESULTS: Fifty-four student-athletes met inclusion criteria and participated in the study. A total of 27.7% of concussed student-athletes who were symptom-free and returned to baseline on ImPACT at rest (i.e. no longer demonstrated performance deficits on neurocognitive tests) exhibited cognitive decline following moderate physical exertion. The PE cognitive changes were not simply general performance effects, but significant changes in memory ability in the presence of intact processing speed functions. The PE-Pass and PE-Fail groups did not, however, differ on post-concussive symptoms or concussion history. CONCLUSIONS: Clinicians' return-to-play evaluation protocols should include post-exertional computerized neurocognitive testing.

Neurocognitive correlates of adult attention-deficit/hyperactivity disorder in a Turkish sample.

We established a neuropsychological testing profile among Turkish adults presenting with ADHD controlling for general intelligence and comorbid psychiatric conditions. Adults with ADHD frequently present with comorbid conditions (e.g., mood and substance use/abuse disorders) that may have a detrimental impact on neurocognitive function. Hence, we excluded patients with ADHD meeting criteria for comorbid psychiatric syndromes. A comprehensive neuropsychological test battery was administered to adults with ADHD attending a general psychiatry clinic in Istanbul, Turkey, and healthy control participants. Adults with ADHD demonstrated performance deficits on tests of attention, information processing speed, and general and working memory. Patients with ADHD also reported a significantly greater number of symptoms associated with frontal lobe syndromes (i.e., dysexecutive symptoms and disinhibition). Patients with ADHD demonstrated rather striking deficits on tests of verbal and nonverbal memory. Once information was encoded, however, patients with ADHD do not demonstrate significant information loss. Patients with ADHD and healthy controls did not differ on tests of alternation learning, inhibitory control (error rates), and ToM skills. Findings support the contention that dorsal-prefrontal (rather than ventral-prefrontal) dysfunction is associated with adult ADHD. Unexpectedly, groups did not differ on executive control and fluency tasks. Yet patients with ADHD obtained substantially higher scores on a self-report measure of executive dysfunction. This suggests that dysexecutive symptoms among patients with ADHD in the current study do not reflect set-shifting or organizational deficits. Rather, symptoms may reflect attentional and working memory deficits as well as diminished information processing speed.

Obsessive-compulsive personality traits: compensatory response to executive function deficit?

Obsessive-compulsive personality traits (OCPTs) may be associated with cognitive disorganization (i.e., executive control deficits). That is, individuals presenting with pronounced OCPTs may rigidly adhere to rules and procedure in an attempt to compensate for cognitive disorganization. We predicted that individuals presenting with OCPTs would demonstrate cognitive disorganization during neurocognitive task performance and would display working memory deficits. To test this hypothesis, we identified a group of university students demonstrating pronounced OCPTs and a comparison group, and administered the Rey-Osterrieth Complex Figure Test (ROCFT). Self-report measures of OCPTs, classical OCD, and depressive symptoms were administered. Students presenting with pronounced OCPTs exhibited performance deficits on the ROCFT. They obtained significantly lower copy organization scores and displayed a subtle visuospatial working memory deficit. Performance deficits on a nonverbal measure of executive control and working memory were related to OCPTs, but were not associated with classic OCD symptoms. Our findings lend support to the contention that specific OCPTs may represent, at least in part, compensatory tactics that evolve in response to executive control deficits.

Neurocognitive function in borderline personality disorder.

A battery of neuropsychological measures considered sensitive to dysfunction in prefrontal or temporal cortices was administered to patients with borderline personality disorder (BPD) and healthy controls. BPD patients exhibited striking deficits on measures of nonverbal executive function and nonverbal memory but were unimpaired on tests of alternation learning, response inhibition, divergent thinking, verbal fluency, and verbal working memory. A second study found that university students obtaining high scores on a self-report measure of BPD symptoms exhibited a similar pattern of neuropsychological impairment, although performance deficits were much less pronounced in the student sample. Taken together, these studies suggest that dysfunction of a right hemisphere frontotemporal regions may be associated with borderline personality.

Cigarette smoking in a student sample: neurocognitive and clinical correlates.

Why do adolescents begin to smoke in the face of profound health risks and aggressive antismoking campaigns? The present study tested predictions based on two theoretical models of tobacco use in young adults: (1) the self-medication model; and (2) the orbitofrontal/disinhibition model. Investigators speculated that a significant number of smokers were self-medicating since nicotine possesses mood-elevating and hedonic properties. The self-medication model predicts that smokers will demonstrate increased rates of psychopathology relative to nonsmokers. Similarly, researchers have suggested that individuals with attention-deficit/hyperactivity disorder (ADHD) employ nicotine to enhance cognitive function. The ADHD/self-medication model predicts that smokers will perform poorly on tests of executive function and report a greater number of ADHD symptoms. A considerable body of research indicates that tobacco use is associated with several related personality traits including extraversion, impulsivity, risk taking, sensation seeking, novelty seeking, and antisocial personality features. Antisocial behavior and related personality traits as well as tobacco use may reflect, in part, a failure to effectively employ reward and punishment cues to guide behavior. This failure may reflect orbitofrontal dysfunction. The orbitofrontal/disinhibition model predicts that smokers will perform poorly on neurocognitive tasks considered sensitive to orbitofrontal dysfunction and will obtain significantly higher scores on measures of behavioral disinhibition and antisocial personality relative to nonsmokers. To test these predictions, we administered a battery of neuropsychological tests, clinical scales, and personality questionnaires to university student smokers and nonsmokers. Results did not support the self-medication model or the ADHD/self-medication model; however, findings were consistent with the orbitofrontal/disinhibition model.

Patterns of Axis-II comorbidity in a Turkish OCD sample.

OBJECTIVE Obsessive-compulsive disorder (OCD) patients frequently present with Axis-II disorders, particularly Cluster C (anxiety spectrum) and Cluster A (schizophrenic spectrum) personality disorders. The present study examined patterns of Axis-II comorbidity in a Turkish OCD sample. In addition, we explored the impact of personality disorder symptoms on OCD-symptom severity and symptom profile. METHOD Structured psychiatric interviews and self-report measures of OCD symptoms and Axis-II disorders were administered to patients with OCD and control subjects. RESULTS Patients with OCD obtained significantly higher scores on measures of Cluster A and Cluster C personality disorders. Patients with OCD also achieved significantly higher scores on the BPD Subscale; however, they did not obtain significantly higher scores on other Cluster B subscales. Group differences on measures of Cluster A and C disorders were marked. CONCLUSIONS Findings are consistent with prior work demonstrating an increased incidence of Axis-II disorders among patients with OCD.

Neuropsychological function in obsessive-compulsive disorder: effects of comorbid conditions on task performance.

BACKGROUND: Neuropsychological testing reveals a pattern of impairment among patients with obsessive-compulsive disorder (OCD) which implicates the orbitofrontal region. Studies of neuropsychological function in OCD differ regarding performance deficits on classical tests of frontal executive function. In some studies, OCD patients did not demonstrate impaired performance on tests of executive function. However, other researchers have documented performance deficits among OCD patients on measures of executive function. Patients with OCD also exhibit performance deficits on tests of visual/spatial memory and verbal memory. Again, in some studies, OCD patients did not demonstrate impaired performance on tests of memory function. How can we account for the conflicting findings? One possibility is that performance deficits on tests of cognitive function are associated with comorbid conditions. In prior work, we observed that OCD patients who did poorly on executive function tasks obtained high scores on a measure of schizotypal personality. A second possibility is that executive function deficits among patients with OCD are associated with comorbid depressive symptoms. METHOD: In the present study, a comprehensive neuropsychological test battery was administered to patients with OCD and matched healthy control subjects. We also administered dimensional measures of schizotypal personality and depression to patients with OCD and controls. We conducted analyses of covariance (ANCOVA), with scores on measures of schizotypal personality and depression used as covariates. RESULTS: OCD patients demonstrated performance deficits on measures of delayed memory, response inhibition, alternation learning, and obtained significantly higher scores on measures of disinhibition, impulsivity, and temporolimbic symptoms; however, OCD patients did not exhibit impaired performance on tests of executive function and verbal fluency, and did not report a significantly greater number of dysexecutive symptoms, when coexistent depressive and schizotypal symptoms were taken into account. CONCLUSION: Findings are consistent with the contention that dysfunction of an orbitofrontal-limbic network underlies OCD.

Assessing adult attention-deficit/hyperactivity disorder: a Turkish version of the current symptoms scale.

We report normative data for a Turkish translation of the Current Symptoms Scale (CSS), a screening measure of adult attention-deficit/hyperactivity disorder (ADHD). The CSS yields 3 scores reflecting diagnostic criteria for: (1) ADHD, predominantly hyperactive-impulsive type; (2) ADHD, predominantly inattentive type, and (3) ADHD, combined type. For comparison purposes, we also present normative data from a community sample in the United States. Central tendency, variability, and correlation patterns among Turkish subjects (n=181) were similar to patterns demonstrated by respondents in the United States (n=114). Mann-Whitney U tests revealed that the Turkish and US groups did not differ significantly on the subscales assessing inattentive and hyperactive-impulsive symptoms. Both versions demonstrated acceptable levels of internal consistency (Cronbach's alpha coefficients ranged from 0.65 to 0.78 for the Turkish version, and from 0.63 to 0.75 for the English version). The Turkish version of the CSS demonstrated excellent test- retest reliability. The test-retest coefficient for the CSS (total score) was 0.82. The inattentive type subscale also showed good test-retest reliability, with r=0.78. The test-retest coefficient for the hyperactive-impulsive type subscale was appreciably lower, with r=0.68; albeit, in the acceptable range. Investigators have determined that many adults, initially diagnosed with ADHD as children, continue to demonstrate clinically significant symptoms. Since adult ADHD is associated with a number of comorbid psychiatric conditions and treatment of the underlying attentional, executive, and impulse control difficulties is associated with a reduction in comorbid psychiatric symptoms, the routine screening for adult ADHD in psychiatric and mental health settings may be warranted.

Subtyping obsessive-compulsive disorder: neuropsychological correlates.

We administered neuropsychological measures considered sensitive to prefrontal dysfunction (both orbitofrontal and dorsolateral prefrontal neocortex) to obsessive-compulsive disorder (OCD) patients and control subjects. OCD subjects exhibited performance deficits, in comparison to community controls, on three measures sensitive to orbitofrontal neocortex dysfunction. Contrary to expectation, OCD patients also exhibited performance deficits on measures sensitive to dorsolateral prefrontal neocortex dysfunction. However, distinct neurocognitive profiles emerged when we examined the impact of comorbid schizotypal personality features on neuropsychological test performance. Primary OCD patients displayed impaired performance on measures sensitive to orbitofrontal dysfunction; however, they did not differ from control subjects on tests of dorsolateral function. OCD subjects presenting with schizotypal personality features performed poorly not only on tests sensitive to orbitofrontal dysfunction, but also on tests sensitive to dorsolateral dysfunction. Findings suggest that OCD can be subdivided into clinical subtypes, and distinct prefrontal subsystems may be differentially involved in these subtypes.

Positive and negative schizotypy in a student sample: neurocognitive and clinical correlates.

Positive and negative schizotypy may represent discrete factors or dimensions. To determine if distinct neurocognitive profiles are associated with these dimensions or factors, we classified university students on the basis of positive and negative schizotypal symptoms and conducted separate analyses. Following prior work in the neuropsychiatric literature, we predicted that subtle prefrontal deficits would be selectively associated with negative schizotypal personality features in a nonclinical student sample. We also investigated the relationship between positive/negative schizotypy and associated clinical states or personality dimensions including antisocial personality disorder, obsessive-compulsive personality traits, generalized and social anxiety, empathy, and impulsivity. Classification of subjects into positive and negative schizotypy groups revealed distinct neurocognitive and clinical profiles. We observed a positive relation between measures of temporolimbic dysfunction, impulsivity, antisocial behavior, and positive schizotypal phenomena. Negative schizotypy was associated with subtle performance deficits on measures of frontal executive function, increased social anxiety, and obsessive-compulsive phenomena. Findings are consistent with the contention that positive and negative schizotypy represent discrete factors.

Partial seizure-like symptoms in borderline personality disorder.

The clinical presentation of borderline personality disorder (BPD) bears a striking resemblance to the behavioral alterations associated with temporal lobe epilepsy. Using the Limbic System Checklist-33, we found that BPD subjects reported more symptoms associated with partial seizures than did control subjects. BPD patients also exhibited deficits on immediate and delayed recall of the Rey-Osterrieth Complex Figure and produced distorted drawings of the Rey Figure. Their degree of impairment correlated with their report of temporolimbic symptoms. Results are consistent with the proposal that temporolimbic dysfunction underlies the behavioral dyscontrol and affective dysregulation present in BPD.