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.
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.
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.
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.
Recent neuroimaging studies and neuropsychological test findings support the contention that prefrontal dysfunction is associated with psychopathic personality traits and antisocial behavior. ...However, conflicting results have arisen regarding performance on measures of frontal executive function. We administered a neuropsychological test battery consisting of measures sensitive to frontal lobe dysfunction and a battery of personality questionnaires and clinical scales sensitive to antisocial personality disorder (APD) subjects presenting with prominent psychopathic personality features and matched control subjects. We also monitored the subjects’ electrodermal activity during the presentation of emotionally charged stimuli. APD subjects showed greater neuropsychological deficits on measures sensitive to orbitofrontal dysfunction in comparison to control participants. Moreover, APD subjects were electrodermally hyporesponsive to aversive stimuli relative to control group members. APD subjects did not demonstrate performance deficits on classical tests of frontal executive function. Participants also underwent clinical assessment. As expected, APD subjects were less conscientious, self-reproaching, guilt-prone, and socially anxious than matched control subjects. Moreover, the scores indicated that APD subjects were more venturesome and uninhibited relative to control subjects. Contrary to expectations, APD subjects and community control subjects did not differ on a self-report measure of sensitivity to specific phobic situations.
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.
There are a number of studies examining clinical and comorbidity profiles among patients with treatment-resistant obsessive-compulsive disorder (TR-OCD); however, there have been far fewer ...investigations of neurocognitive function among such patients. Five patients with treatment-refractory obsessive-compulsive symptoms underwent neurocognitive and clinical/personality testing. A number of TR-OCD patients met diagnostic criteria for major axis I disorders (particularly mood and anxiety disorders) as well as clusters A, B, and C personality disorders. TR-OCD patients demonstrated significant performance deficits on neurocognitive tests of visuospatial working memory, visuoconstructive ability, and executive control as well as one test of processing speed, but not a second, relative to healthy normative controls. TR-OCD patients and normative controls did not differ significantly on measures of verbal working memory, sequencing, figure copy organization, inhibitory control, and odor identification. In addition, TR-OCD patients were directly compared to five healthy controls evaluated in our laboratory for a separate unpublished study. TR-OCD patients demonstrated significant performance deficits on tests of visuospatial working memory, information processing speed, and executive control, and obtained substantially higher scores on dimensional measures of social anxiety and depressive symptom severity, but not schizotypal personality features. Group differences of tests of verbal working memory, inhibitory control, and additional tests of executive function were not significant. In summary, patients with TR-OCD presented with comorbid axis I conditions (primarily mood and anxiety disorders) and personality disorders. TR-OCD patients demonstrated deficits on some, but not all, tests of working memory and executive control. Neurocognitive test findings lend partial support to the hypothesis that right hemisphere (particularly dorsolateral-prefrontal, but not orbitofrontal) dysfunction is associated with TR-OCD, and a number of TR-OCD patients met diagnostic criteria for major axis I disorders (particularly mood and anxiety disorders) as well as cluster A, B, and C personality disorders further complicating treatment.
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.
Celotno besedilo
Dostopno za:
DOBA, IJS, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
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.
Bu çalışmanın amacı, sigara kullanımını kişilik özellikleri ve nöropsikolojik test performansı açısından incelemektir. Bu amaç doğrultusunda, sigara içen (n=28), sigarayı bırakmış (n=18) ve hayatı ...boyunca hiç sigara içmemiş (n=43) üniversite öğrencilerine, çeşitli klinik ve kişilik testleri ile kapsamlı bir nöropsikolojik test bataryası uygulanmıştır. Kişilik özellikleri ve/veya bozuklukları açısından elde edilen sonuçlar, sigara içenlerin, içmeyenler ve bırakanlara göre; yenilik arayışı, heyecan ve deneyim arama, maceraperestlik ve disinhibisyon gibi kişilik boyutlarında daha yüksek puan aldıklarını bununla birlikte obsesif-kompulsif ve kaçıngan kişilik bozukluğunu ölçen testlerde daha düşük puan aldıklarını göstermiştir. Nöropsikolojik test performansı açısından ise, dorsalateral prefrontal korteks disfonksiyonuna duyarlı olan nöropsikolojik testlerde sigara içenler, içmeyenler ve bırakanlar kadar iyi performans sergilerken, kural ihlali gibi orbitofrontal korteks disfonksiyonu ve inhibisyon kontrolüne duyarlı olan nöropsikolojik testlerde ise sigara içenlerin, içmeyen ve bırakanlara göre daha kötü performans sergilediği tespit edilmiştir. Elde edilen bulgular, orbitofrontal korteksin sigara kullanımında kritik bir rol oynadığına işaret etmektedir.
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