Wisconsin Card Sorting Test deficits in chronic paranoid schizophrenia. Evidence for a relatively discrete subgroup?

Some, although not all, researchers have reported dramatically increased numbers of perseverative responses on the Wisconsin Card Sorting Test (WCST) in schizophrenic patients compared to normal comparison subjects. The current study was designed to further explore the nature of possible WCST deficits in a group of paranoid schizophrenic patients compared to normal and psychiatric comparison subjects. In the current study, schizophrenic patients had significantly greater numbers of perserverative responses on the WCST than the comparison groups. The sample of patients with schizophrenia appeared to be characterized by a non-Gaussian distribution of perseverative responses on the WCST. WCST-impaired and WCST-nonimpaired schizophrenic subgroups were compared on cognitive and symptom measures, and increased perseverative responding was associated with negative symptoms, slowed reaction time, and more hospitalizations. While additional research is necessary to further investigate hypotheses of frontal versus generalized brain dysfunction in schizophrenic patients, WCST impairment seems to be present in a clinically meaningful subgroup of paranoid schizophrenic patients.     

Wisconsin Card Sorting Test performance before and after temporal lobectomy

Wisconsin Card Sorting Test (WCST) performance was studied before and after patients underwent right (n = 34) or left (n = 34) temporal lobectomy. Patients had hemisphere language dominance judged on intracarotid amobarbital testing and were free of space-occupying lesional pathology by magnetic resonance imaging (MRI). Right and left lobectomy patients did not differ before or after surgery on WCST parameters: categories completed, perseverative errors, total correct responses, total errors, nonperseverative errors, and perseverative responses. There was no relationship between WCST performance and MRI-determined hippocampal volumes or age of recurrent seizure onset. These findings are contrary to previous reports, suggesting the presence of laterality effects on preoperative WCST performance, relationships between WCST performance and age of seizure onset, and association of WCST performance and degree of mesial temporal sclerosis. Data from this study are consistent with a report on a larger group of temporal lobectomy patients, which found no laterality effect on WCST performance. The WCST seems to be of no value when attempting to lateralize seizure onset in nonlesional temporal lobe epilepsy.     

Differences between paranoid and nonparanoid schizophrenic patients on the somatosensory P300 event-related potential

Event-related potentials were recorded from schizophrenic patients (n = 30) and healthy controls (n = 30) using a somatosensory-reaction-time version of the oddball paradigm, by stimulating the right and the left median nerve. Latency, amplitude, duration and area of the P300 were measured. The patient group was subdivided into a paranoid (n = 16) and a nonparanoid (n = 14) subgroup and each was compared to controls. After stimulation of the right median nerve the nonparanoid group had a significantly prolonged P300 latency and a normal amplitude. The paranoid subgroup had a trend toward reduction of the P300 amplitude; its P300 latency was normal. After stimulation of the left median nerve, a prolongation of the P300 latency was observed in the paranoid subgroup. This subgroup had also a reduced P300 amplitude, while the nonparanoid patients had both values comparable to those of the controls. Duration and area were not significantly different between the two subgroups of patients and controls. Paranoid and nonparanoid patients showed a different behavior on reaction time parameters. No relationship was observed between P300 parameters and clinical ratings, neuroleptic dose and demographic data. The P300 parameters did not correlate with the reaction time measures. These results are discussed in terms of a disturbance of CNS inhibitory mechanisms in cognitive processes of paranoid schizophrenic patients and could be a further indication that different subtypes of schizophrenia may have different biological substrates.     

A distinctive interaction between chronic anxiety and problem solving in asymptomatic APOE e4 homozygotes

We correlated measures of problem solving (Wisconsin Card Sorting Test [WCST] categories, total errors, and perseverative errors) and chronic anxiety (Personality Assessment Inventory Anxiety Scale [ANX]) in asymptomatic apolipoprotein E (APOE) e4 homozygotes (HMZs), heterozygotes, and noncarriers (NC) (n = 42 in each group) matched for age, education, and gender. Differences between HMZ and NC in the slope of the regression of WCST scores on ANX reached statistical significance on all three WCST measures. Chronic anxiety adversely affects cognitive skills in all groups, and is associated with significantly greater decline in problem solving skills in cognitively normal APOE e4 HMZ.     

Do schizophrenia patients make more perseverative than non-perseverative errors on the Wisconsin Card Sorting Test? A meta-analytic study

The Wisconsin Card Sorting Test (WCST) is widely used to explore executive functions in patients with schizophrenia. Among other findings, a higher number of perseverative errors has been suggested to implicate a deficit in task switching and inhibitory functions in schizophrenia. Many studies of patients with schizophrenia have focused on perseverative errors as the primary performance index in the WCST. However, do schizophrenia patients characteristically make more perseverative than non-perseverative errors compared with healthy controls? We reviewed the literature where schizophrenia patients were engaged in the WCST irrespective of the primary goal of the study. The results showed that while both schizophrenia patients and healthy participants made more perseverative than non-perseverative errors, the contrast between perseverative and non-perseverative errors is higher in schizophrenia patients only at a marginal level of significance. This result suggests that schizophrenia patients do make a comparable number of non-perseverative errors and cautions against simplistic interpretation of poor performance of schizophrenia patients in WCST as entirely resulting from impairment in set-shifting or inhibitory functions.     

Emotion recognition in Chinese people with schizophrenia

This study examined whether people with paranoid or nonparanoid schizophrenia would show emotion-recognition deficits, both facial and prosodic. Furthermore, this study examined the neuropsychological predictors of emotion-recognition ability in people with schizophrenia. Participants comprised 86 people, of whom: 43 were people diagnosed with schizophrenia and 43 were controls. The 43 clinical participants were placed in either the paranoid group (n=19) or the nonparanoid group (n=24). Each participant was administered the Facial Emotion Recognition task and the Prosodic Recognition task, together with other neuropsychological measures of attention and visual perception. People suffering from nonparanoid schizophrenia were found to have deficits in both facial and prosodic emotion recognition, after correction for the differences in the intelligence and depression scores between the two groups. Furthermore, spatial perception was observed to be the best predictor of facial emotion identification in individuals with nonparanoid schizophrenia, whereas attentional processing control predicted both prosodic emotion identification and discrimination in nonparanoid schizophrenia patients. Our findings suggest that patients with schizophrenia in remission may still suffer from impairment of certain aspects of emotion recognition.     

Impaired Wisconsin card sorting test performance in first-episode schizophrenia: resource or motivation deficit?

Patients with first-episode schizophrenia (n = 27) and age- and education-matched healthy controls (n = 27) were administered the standard version of the Wisconsin Card Sorting Test (WCST), the Wechsler Adult Intelligence Scale-Revised (WAIS-R), and the Rorschach according to the Comprehensive System (CS). Schizophrenic patients achieved a significantly lower full-scale IQ and made more perseverative responses and achieved fewer categories on the WCST than the healthy control group. No significant associations were observed between effort or motivation and WCST performance. Schizophrenic patients who made more perseverative responses tended to be impoverished in terms of available resources, and functioned in a simplistic way when attending to details of the stimulus field. First-episode schizophrenics are able to generate motives and initiate goal-directed activity, but some of them fail to achieve their goals because the cognitive abilities and available resources required for effective planning, purposeful action, or effective performance are impaired.     

Wisconsin Card Sorting Test performance in patients with complex partial seizures of temporal-lobe origin

Wisconsin Card Sorting Test (WCST) performance was investigated in patients with complex partial seizures (CPS) of dominant (n = 16) or nondominant (n = 19) temporal-lobe origin as well as in an epilepsy control group (n = 6) which consisted largely of patients with primary generalized epilepsies. Fifty seven percent of the CPS group (39% of dominant and 74% of nondominant temporal-lobe patients) performed in a manner suggestive of frontal-lobe pathology compared to 17% of the epilepsy controls. There were no differences among the groups in the number of categories achieved, but there were substantial qualitative differences in problem-solving efficiency. Nondominant temporal patients manifested more total errors and perseverative errors relative to both dominant temporal and epilepsy controls, and more perseverative responses relative to epilepsy controls. Dominant temporal-lobe patients showed more perseverative errors than epilepsy controls. Finally, a consecutive series of patients who underwent partial temporal-lobe resection were examined 6 months post-surgically and they were found to manifest significantly fewer perseverative responses. The possible reasons for "frontal-like" performance in CPS patients with documented temporal-lobe pathology are discussed and a specific hypothesis is suggested.     

Performance of patients with schizophrenia on the Wisconsin Card Sorting Test (WCST)

OBJECTIVE: To directly compare the performance of patients with schizophrenia and control subjects on the Wisconsin Card Sorting Test (WCST). Specifically, we sought to verify if there are significant differences on the "classical" WCST measurements (perseverative errors and number of categories), as well as on more rarely reported scores, and assess the extent to which patients with schizophrenia can improve their performance with card-by-card instructions and continuous verbal reinforcement. DESIGN: Prospective cross-sectional study. SETTING: Psychiatry department in a university-affiliated hospital. PARTICIPANTS: 30 patients with schizophrenia, diagnosed according to DSM-IV criteria, and 30 control subjects, matched to patients according to age and education. INTERVENTION: The WCST was administered according to the criteria of Heaton, and a subgroup of the patients with schizophrenia was given a retest after an explanation of the WCST and verbal reinforcements. RESULTS: Patients with schizophrenia succeeded on fewer categories (t = 23.3, p < 0.001), committed more perseverative errors (t = 15.6, p < 0.001), made more perseverative responses (t = 14.6, p < 0.001), needed more trials to succeed at the first category (t = 9.2, p < 0.003) and gave significantly lower conceptual level responses (t = 14.1, p < 0.001) than the controls. However, on retest, patients with schizophrenia committed significantly fewer perseverative errors (t = 5.1, p < 0.001) and showed higher conceptual level responses (t = -3.45, p < 0.003). CONCLUSION: Consistent with a hypothesis of frontal dysfunction in schizophrenia, patients with schizophrenia tend to show a perseverative deficit; however, some are able to partially overcome this deficit when given verbal reinforcement.     

发作期抑郁症患者脑动脉血流速度与注意力、执行功能关系

目的探讨发作期抑郁症患者脑动脉血流速度及其与注意力、执行功能的关系。方法 70例发作期抑郁症患者及65名健康对照纳入研究。采用24项汉密尔顿抑郁量表(24 items Hamilton depression scale,HAMD-24)评估抑郁症患者抑郁情绪,划销测验(cancellation test,CT)、威斯康星卡片分类测验(Wisconsin card sorting test,WCST)评估的认知功能,采用经颅多普勒超声(transcranial Doppler,TCD)检测脑动脉血流速度。结果与对照组比较,发作期抑郁症患者基底动脉、左侧大脑中动脉、右侧大脑中动脉、左大脑前动脉与右大脑前动脉平均血流速度均减慢,差异具有统计学意义(P0.05)。患者组CT各阶段净分及总净分低于对照组,而WCST总应答数、错误应答数、持续性错误数、完成第一个分类所需应答数均高于对照组,差异具有统计学意义(P0.01)。发作期抑郁症患者大脑基底动脉(r=0.25)、左中动脉(r=0.46)、右中动脉(r=0.25)、右后动脉(r=0.26)平均血流速度与CT总净分呈正相关(P0.05),各大脑动脉平均血流速度与WCST总应答数、持续性错误数呈负相关(P0.05),基底动脉、左右后动脉与错误应答数、完成第一个分类所需应答数呈负相关(P0.05)。结论发作期抑郁症患者大脑动脉平均血流速度普遍降低,注意力与执行功能受损。认知功能受损可能与脑动脉平均血流速度的改变有关。     

Spatial working memory performance in patients with schizoaffective psychosis versus schizophrenia: a tale of two disorders?

We explored the relationship between schizophrenia and schizoaffective disorder by comparing the two patient groups in terms of their performance on measures of executive functioning (spatial working memory and Wisconsin Card Sorting Test). Patients with schizophrenia (N=34) and those with schizoaffective disorder (N=23) performed significantly poorer than community controls (N=30). However, the schizoaffective and schizophrenia groups did not differ from each other in terms of working memory accuracy or mean response latencies. Similarly, the two patient groups did not differ in terms of the number of categories achieved or number of perseverative errors on the Wisconsin Card Sorting Test. Among the patients, working memory accuracy was associated with number of WCST perseverative errors and number of categories achieved, though working memory performance was not associated with number of WCST nonperseverative errors. These findings indicate that both schizophrenia and schizoaffective disorder are associated with executive functioning deficits. The findings are discussed in the context of the ongoing debate regarding the conceptualization of schizoaffective disorder.     

Executive functions and P300 latency in elderly depressed patients and control subjects.

The authors asked whether impaired executive functioning and long P300 latency are related dysfunctions and whether they are associated with geriatric depression. A group of 25 elderly depressed patients without dementia and 20 control subjects were assessed on tasks of fluency, initiation and perseveration, the Stroop task, the Wisconsin Card Sorting Test (WCST) perseverative error score, and P300 latency. The groups' performance differed significantly on these tasks and in P300 latency. Longer latency was associated with poorer performance in both groups on all measures except WCST perseverative errors. Regardless of patients' depression status, increased P300 latency predicts poorer performance on executive function tasks requiring speeded performance.     

Elderly schizophrenic inpatients in the wake of deinstitutionalization

The authors investigated the factors relating to the observation that in a large state hospital, there is an age-related increase in the ratio of patients with a DSM-II diagnosis of paranoid schizophrenia to those with a diagnosis of nonparanoid schizophrenia. Elderly inpatients (N = 1,518) treated over a 5-year period were studied and the hypotheses of proportionately greater numbers with late onset of paranoid conditions, longer lengths of stay for recently admitted paranoid patients, and changing diagnosis over time were tested and rejected. The data suggest that the buildup among the elderly of those diagnosed under DSM-II to have paranoid conditions is due to patients admitted well before age 54. The authors discuss the reasons for the poor prognosis of this group.     

Patterns of prefrontal dysfunction in alcoholics with and without Korsakoff’s syndrome, patients with Parkinson’s disease, and patients with rupture and repair of the anterior communicating artery

This study compared patterns of frontal-lobe dysfunction in alcoholics with Korsakoff’s syndrome (KS: n = 9), non-Korsakoff alcoholics (AL: n = 28), patients with Parkinson’s disease (PD: n = 18), and patients with rupture and repair of the anterior communicating artery (ACoA: n = 4) relative to healthy non-neurological control (NC) participants (n = 70). The tests administered were sensitive to functions of dorsolateral prefrontal and orbito-frontal subsystems. Measures included perseverative errors on the Wisconsin Card Sorting Test (WCST-pe), errors on object alternation (OA), errors on Trails B, number of words generated on the Controlled Oral Word Association Test (COWAT), and number of categories completed on the WCST (WCST-cc). KS patients were as impaired as AL participants on orbitofrontal measures and, on dorsolateral prefrontal measures, were impaired relative to AL participants, whose performance did not differ from controls. Patients with PD also were impaired on tests of orbitofrontal and dorsolateral prefrontal functioning but to a lesser extent than the KS patients. Moreover, most of the PD deficits were driven by the impaired performance of patients whose initial symptoms were on the right side of the body. The ACoA patients were significantly impaired on tests of orbitofrontal but not dorsolateral prefrontal functioning relative to the control group. Together, the results confirm different patterns of frontal-system impairments in patient groups having compromised frontal lobe functioning consequent to varying etiologies.     

A process approach to verbal memory assessment: Exploratory evidence of inefficient learning in women remitted from anorexia nervosa

Introduction: Anorexia nervosa (AN) is associated with deficits in set-shifting and cognitive flexibility, yet less is known about the persistence of these deficits after recovery and how they might contribute to reported difficulties organizing and learning new information. To address this question, the current study applied a process-focused approach, that accounts for errors and strategies by which a score is achieved, to investigate the relationship between verbal memory and executive function in women remitted from AN.

Method: Twenty-six women remitted from anorexia nervosa (RAN) and 25 control women (CW) aged 19–45 completed the California Verbal Learning Test, Second edition (CVLT-II) and the Wisconsin Card Sorting Test (WCST). Groups were compared on overall achievement scores, and on repetition, intrusion, and perseverative errors on both tests. Associations between learning and memory performance and WCST errors were also examined.

Results: RAN and CW groups did not differ on overall CVLT-II learning and memory performance or errors on the WCST, though the RAN group trended towards greater WCST non-perseverative and total errors. On the CVLT-II, the RAN group made significantly more repetition errors than CW (p = 0.010), and within-trial perseveration (WTP) errors (p = 0.044). For the CW group, CVLT-II learning and memory performance were negatively associated with errors on the WCST, whereas among RAN, primarily delayed memory was negatively correlated with WCST errors. Notably, for RAN, greater WCST perseverative responses were correlated with greater CVLT-II repetition and WTP errors, showing the convergence of perseverative responding across tasks.

Conclusions: Despite similar overall learning and memory performance, difficulties with executive control seem to persist even after symptom remission in patients with AN. Results indicate an inefficient learning process in the cognitive phenotype of AN and support the use of process approaches to refine neuropsychological assessment of AN by accounting for strategy use.     

奥氮平对精神分裂症患者执行功能障碍的影响

目的:探讨奥氮平对精神分裂症患者执行功能障碍的长期疗效。方法:对29例服用奥氮平维持治疗与24例服用氯丙嗪维持治疗的精神分裂症患者进行2年随访,采用威斯康星卡片分类测验(WCST)评估执行功能。结果:维持治疗2年末奥氮平组和氯丙嗪组的WCST测验中的总测验次数、持续错误数、随机错误数均显著下降(P<0.05或P<0.01),但奥氮平组的总测验次数、持续错误数、随机错误数减分率均显著高于氯丙嗪组(P均<0.01)。结论:奥氮平长期维持治疗能显著改善精神分裂症患者的执行功能。     

Seasons of birth and subtypes of schizophrenia

Many studies show a higher rate of birth of schizophrenic patients during the winter and early spring months. This is particularly prominent in studies involving northern European countries and the northern part of the United States. The interpretations for this apparent seasonality remain highly speculative. We examined the seasons of birth of 472 patients carrying the diagnosis of schizophrenia. We also studied the gender and paranoid vs nonparanoid subtypes of this subject group. The total group does not show an excess of winter births. The same is true for total male (n = 193) and total female (n = 279) schizophrenic patients. The different subtypes of female patients show a homogenous distribution by seasons of birth; but the male paranoid schizophrenia group (n = 102) shows a significant increase of births during the first quarter of the year. The findings are interpreted according to the prevailing hypotheses of schizophrenia. The implications of these findings are discussed.     

Dissociation of ketamine effects on rule acquisition and rule implementation: possible relevance to NMDA receptor contributions to executive cognitive functions.

BACKGROUND: The demands of the Wisconsin Card Sorting Test (WCST) change with experience. This report contains two studies designed to examine N-methyl-D-aspartate (NMDA) receptor contributions to the executive components of WCST performance. These aspects of WCST performance figure more prominently in the initial completion of this task than in subsequent task repetitions in healthy populations. METHODS: In the first study, healthy subjects (n = 15) completed the WCST on two occasions separated by 1 week. In the second study, healthy subjects (n = 22) completed two test days spaced by approximately 1 week, during which, they completed the WCST and other assessments after administration of the NMDA antagonist ketamine (intravenous bolus 0.26 mg/kg followed by infusion of 0.65 mg/kg/hour) or matched placebo. RESULTS: In the first study, subjects reduced the number of total and perseverative errors with a single repetition of the WCST. In the second study, ketamine significantly increased the number of total errors and the number and percent of perseverative errors on the first, but not the second test day. Similarly, it reduced the number of category criteria met on the first, but not second test day. Ketamine also increased distractibility, impaired recall, produced psychosis, altered perception, and had effects resembling the negative symptoms of schizophrenia. However, only WCST performance showed order dependency. CONCLUSIONS: This order dependency further implicates NMDA receptors in executive cognitive functions associated with the frontal cortex.     

Working memory and Wisconsin Card Sorting Test performance in schizotypic individuals: a replication and extension

The present study examined spatial working memory and Wisconsin Card Sorting Test (WCST) performance in psychosis-prone individuals, either those with extremely high scores on the Social Anhedonia Scale (SocAnh; n = 49) or deviant scores on the Perceptual Aberration-Magical Ideation Scales (Per-Mag; n = 66). Sixty-three individuals with normal scores on the Chapman Psychosis-Proneness Scales served as control subjects. In order to evaluate working memory performance, participants were administered three tasks, namely, sensorimotor, degraded stimulus, and delayed-response tasks. Although the SocAnh and Per-Mag groups displayed poorer performance than control subjects on the working memory task, they did not differ significantly from each other. The SocAnh group exhibited slower reaction times on the working memory task compared to the control group. The groups did not differ in their performance on sensorimotor or degraded stimulus control tasks. Both psychosis-prone groups differed significantly from control subjects in terms of their WCST performance. Working memory performance was inversely associated with the number of perseverative errors (r = -0.17) and the number of trials to complete the first category on the WCST (r= -0.15). These findings extend the literature by indicating that some psychosis-prone individuals with social-interpersonal schizotypal deficits also display subtle spatial working memory impairments.     

Cerebral asymmetry in subtypes of schizophrenia

CT scans of 26 nonparanoid and 10 paranoid right-handed male schizophrenics were examined. Multiple measurements were made of each region of the brain and a standard error of measurement with a confidence level of p less than .01 was used to define significant asymmetry. Three aspects of cerebral asymmetry, i.e., local hemispheric width, local hemispheric protrusion, and regional hemispheric size, were examined. Paranoid and nonparanoid patients were similar in their patterns of frontal asymmetries. However, a substantial proportion of nonparanoid schizophrenics had wider, longer, and larger right parieto-occipital lobes compared to paranoid patients.