Relationship between psychopathology and cognitive functioning in schizophrenia

The purpose of this study was to delineate the relationship between positive, negative, cognitive, depressive, and excitement symptom dimensions of schizophrenia and cognitive functioning. Fifty-eight patients with schizophrenia (DSM-IV criteria) were assessed using the Positive and Negative Syndrome Scale (PANSS) and a battery of neuropsychological tests (executive function/abstraction, verbal and spatial working memory, verbal and nonverbal memory/learning, attention, visuospatial ability, and psychomotor speed). The cognitive symptom dimension correlated with executive functions, attention, verbal memory, and spatial ability. Severity of the negative symptom dimension was related to impairment in the structure of the semantic knowledge system, verbal memory, and auditory attention. In contrast, severity of the positive symptom dimension correlated only with impairment in the structure of the semantic knowledge system, and psychomotor speed. Finally, severity of the depressive and excitement symptom dimension was not associated with cognition. Correlations between symptom dimensions and cognitive measures were at best modest. Severity of cognitive and negative symptoms was mainly correlated with deficits on executive functions, semantic memory, and verbal memory, while positive symptoms only with semantic memory. These correlations were modest, suggesting that psychopathology and cognitive deficits in schizophrenia are caused, at least partially, by distinct pathophysiological processes.     

Longitudinal study of cognitive function in first-episode and recent-onset schizophrenia.

OBJECTIVE: Whether cognitive function in schizophrenia deteriorates, improves, or remains stable is a crucial question. Few studies have examined the longitudinal stability of cognitive function and the relationship between cognitive performance and clinical symptoms over time in a cohort of well-treated patients with schizophrenia. METHOD: In the present study, 54 patients with first-episode and recent-onset schizophrenia completed a comprehensive cognitive test battery and were rated on symptom measures at index hospitalization and again after 5 years. RESULTS: Performance IQ and full-scale IQ significantly improved, whereas verbal IQ did not change. Group performance improved on some of the neuropsychological tests, including the Circle A letter-cancellation task, free recall of logical memory test score, and the Wisconsin Card Sorting Test. Mean finger-tapping performance worsened over time, whereas performance on other neuropsychological tests did not change. Negative, psychotic, and disorganized symptoms significantly improved over the time period. Changes in negative symptoms were correlated with performance changes in verbal IQ and full-scale IQ but not performance IQ. Improvement in verbal cognition was observed when negative symptoms improved. Psychotic and disorganized symptom dimensions were not correlated with any IQ measure. CONCLUSIONS: These results indicate that in a cohort of young patients receiving neuroleptic treatment early in their illness, cognitive performance does not deteriorate--and may improve. Only one of the three symptom dimensions--negative--was associated with change in cognitive performance. This study supports the view that negative symptoms are associated with a poor long-term cognitive outcome and may be closely related to the primary cognitive deficit in schizophrenia.     

Cognitive correlates of the negative, disorganized, and psychotic symptom dimensions of schizophrenia

Knowledge of the relationship between specific cognitive abnormalities and the clinical symptoms of schizophrenia could give insight into the nature of their underlying pathophysiology. Composite scores were generated for negative, disorganized, and psychotic symptom ratings in 134 patients with schizophrenia (DSM-IV criteria). Partial correlations (each composite corrected for the others) were computed with neuropsychological measures. Negative symptoms were related to poor performance on tests of verbal learning and memory, verbal fluency, visual memory, and visual-motor sequencing. Disorganized symptoms were correlated with lower verbal IQ and poor concept attainment. Psychotic symptoms had no significant relationship with cognitive deficit.     

Humor appreciation deficit in schizophrenia: the relevance of basic neurocognitive functioning

The purpose in undertaking the present study was to investigate humor appreciation in patients with schizophrenia. Moreover, we sought to explore the potential relationship of humor appreciation with measures of psychopathology and cognitive functioning among the patients. Thirty-six patients with schizophrenia were compared with 31 normal controls matched for age, sex, and education on a computerized test comprising captionless cartoons: Penn's Humor Appreciation Test (PHAT). The patients were also evaluated on the symptom dimensions derived from the Positive and Negative Symptom Scale (positive symptoms, negative symptoms, cognitive symptoms, depression, and excitement), as well as a battery of neuropsychological tests measuring executive functions, attention, working memory, verbal and visual memory, visuospatial ability, and psychomotor speed. Patients with schizophrenia had significantly lower scores on the PHAT than normal controls. The patients' performance on the PHAT correlated with scores on Penn's Continuous Performance Test, the Stroop Color-Word Test, and the phonological subscale of the Greek Verbal Fluency Test. Our findings indicated impaired humor appreciation among patients with schizophrenia. The relationship found between the appreciation of captionless cartoons involved an incongruous detail and performance on a broad neuropsychological battery suggested that the deficit in humor appreciation in schizophrenia could be attributed to impairment in more basic neurocognitive domains, namely, selective and sustained attention as well as phonological word fluency.     

The convergence of neuropsychological testing and clinical ratings of cognitive impairment in patients with schizophrenia.

This study examined the relationship between clinical rating of cognitive symptoms and performance on neuropsychological tests in acute and chronic samples of patients with schizophrenia. Two separate studies examined patients who varied widely in their lifetime functional outcome, including 263 elderly poor-outcome inpatients and 20 acutely admitted patients. In the first study, six cognitive performance measures were collected, and in the second study, five different measures were collected. Correlations with different symptom models of cognitive and negative symptoms were examined. In both samples, cognitive symptoms were never more highly correlated with cognitive test performance than with negative symptoms. When cognitive and negative symptom ratings were combined, they never accounted for as much as half of the variance in performance on the cognitive tests in both samples. These data suggest that clinical assessment of symptoms is not a viable alternative to neuropsychological testing to obtain information about cognitive functioning in schizophrenia. These results may also be specific to the clinical rating scale used, the Positive and Negative Syndrome Scale (PANSS).     

Community dysfunction in schizophrenia: rate-limiting factors

The purpose of the present study was to investigate the impact of cognitive functioning, psychopathology, and severity of extrapyramidal side effects on community outcome in a group of Greek outpatients with schizophrenia. Participants were 40 outpatients with schizophrenia (25 men). Social adjustment was assessed with the Quality of Life Scale (QLS). Severity of symptoms of schizophrenia was measured with the Positive and Negative Syndrome Scale (PANNS), and extrapyramidal symptoms with the Extrapyramidal Symptom Rating Scale (ESRS). Finally, a battery of neuropsychological tests was administered in order to assess the following cognitive domains: executive functioning/set shifting, executive functioning/inhibition, fluency, verbal memory, visual memory, working memory, attention, visuospatial ability, and psychomotor speed/visual scanning. Total scores on the QLS were significantly correlated with negative symptoms, parkinsonism, and performance on the fluency tasks. Interpersonal relations subscale was significantly related with negative symptoms and fluency. No significant relationship was found between the Instrumental Role Functioning subscale and the PANSS, ESRS, or any cognitive domain. Scores on the Intrapsychic Foundation subscale were significantly correlated with negative symptoms and fluency. Finally, scores on the Common Objects and Activities subscale were significantly related with severity of negative symptoms, parkinsonism and visual memory. Our findings suggest that severity of negative symptoms, cognitive dysfunction, especially performance on fluency tasks and visual memory, as well as parkinsonism, are important determinants of functional outcome in schizophrenia.     

Treatment of cognitive impairment in early psychosis: a comparison of risperidone and haloperidol in a large long-term trial

OBJECTIVE: Cognitive impairment is a major determinant of functional outcome in schizophrenia. Treatment of cognitive impairment at the time of the first episode may have the potential to change functional outcomes of the illness. This study examined changes associated with treatment with risperidone compared with haloperidol in aspects of cognitive functioning known to be associated with functional outcomes. The study was conducted in a large group of patients experiencing their first episode of schizophrenia. METHOD: Cognitive assessments were conducted in 533 patients experiencing their first episode of schizophrenia or a related psychosis who had been randomly assigned to receive low doses of risperidone or haloperidol. The cognitive assessments were repeated at several different follow-up intervals; 359 patients were reexamined at the 3-month follow-up. The assessments included examinations of verbal and visuospatial episodic memory, vigilance, executive functioning, processing speed, and verbal fluency. Patients' clinical symptoms were also rated with the Positive and Negative Syndrome Scale. RESULTS: Improvements from baseline were found in the risperidone-treated patients for episodic memory, verbal fluency, vigilance, executive functioning, and visuomotor speed. Haloperidol-treated patients also showed improvements from baseline in episodic memory, vigilance, and visuomotor speed but not in executive functioning or verbal fluency. Comparison of differential treatment effects on a composite measure of cognitive functioning found that risperidone was significantly more beneficial than haloperidol after 3 months of treatment. Changes in Positive and Negative Syndrome Scale scores were correlated overall with improvement in the haloperidol-treated patients but not in the risperidone-treated patients. CONCLUSIONS: Treatment with risperidone at the time of the first episode of schizophrenia is associated with wide-ranging improvements in cognitive functioning. Overall improvement is significantly greater with risperidone than with haloperidol. Further, cognitive improvement associated with treatment with risperidone was not influenced by changes in symptoms, but that relationship was significant in haloperidol-treated patients.     

Neurocognitive performance and negative symptoms: are they equal in explaining disability in schizophrenia outpatients?

OBJECTIVE: The aim of this study is to assess if cognitive variables and symptom dimensions can predict disability in a sample of outpatients with schizophrenia. METHOD: A cross-sectional sample of 113 individuals with a diagnosis of schizophrenia (DSM-IV criteria) was selected from a computerized register of five Community Mental Health Centers. Patients were assessed by two trained psychologists, with a neuropsychological battery comprising measures for verbal memory, attention, operative memory and abstraction and flexibility functions. Symptoms were assessed with the Positive and Negative Syndrome Scale (PANSS); a socio-demographic and clinical questionnaire, comprising the Disability Assessment Scale (DAS), was also completed. Test scores were standardized (t scores) to performance of healthy controls. To assess the relationship between clinical and sociodemographic factors and disability and cognitive functioning Pearson's correlation coefficients were computed. In order to establish the predictive capacity of the cognitive, clinical and symptom variables on disability linear regression models were fitted. RESULTS: Mean age of patients was 41.6 years and 68% were male. Higher ratings in the negative dimension were associated with more cognitive deficits. Association with the positive dimension was present but less strong. All disability areas, except for disability in occupational functioning, were partially explained by the negative dimension. Disability in family functioning was also partially explained by attention and number of admissions since onset. CONCLUSION: Negative symptoms are the major source of disability of our sample and are also associated to cognitive functioning. The present findings suggest that further investigation on the mediators between clinical and social outcomes may help to design specific treatments to reduce disability.     

精神分裂症认知功能状况及影响因素

目的　探讨精神分裂症认知功能的状况及影响因素。方法　对 36例精神分裂症患者在治疗前、治疗后 6周作神经心理测验和阴性及阳性症状量表 (PANSS)、临床总体印象量表 (CGI)、副反应量表 (TESS)、锥体外系副反应量表 (RSESE)的评定 ,并以 36名健康人进行对照。结果　精神分裂症患者与正常对照组比较 ,两组在知识、算术、数字符号、数字广度 (顺、逆 )、木块拼图、瞬时逻辑记忆、视觉再生即刻和延迟、STROOPC W正确数、词汇流畅、TOH总分 ,计划时间、延迟逻辑记忆、WCST所有指标有显著差异 (P <0 0 5 )。阳性症状量表减分率与视觉再生及WCST分类个数成绩的提高呈显著正相关。而阴性症状量表减分率与瞬时逻辑记忆成绩的提高呈显著正相关。安坦的剂量与木块拼图、瞬时逻辑记忆及WCST分类个数 3项成绩的提高呈显著负相关。安定的药量与算术、视觉再生、汉诺塔总分的改善呈显著负相关。结论　精神分裂症患者存在广泛的认知功能的损害 ,其认知功能可能受到阳性症状、阴性症状、安坦及安定药量的影响。     

Cognitive and clinical predictors of success in vocational rehabilitation in schizophrenia

Cognitive impairments in schizophrenia appear to be associated with social problem solving, social and vocational functioning, and psychosocial skill acquisition. The present study examined the relationship of cognitive functioning, as well as clinical symptoms, to vocational outcomes among individuals with schizophrenia. One hundred and twelve participants with DSM-IV schizophrenia spectrum diagnoses underwent a comprehensive neuropsychiatric evaluation after enrolling in one of several employment programs. The neuropsychological evaluation examined verbal learning and memory, attention, speed of information processing, and executive functioning. Clinical symptoms were evaluated with the Positive and Negative Syndrome Scale (PANSS). Vocational outcomes were assessed 4 months after baseline assessment and included both measures of employment outcome (e.g., earnings) and of work performance as assessed by the Work Behavior Inventory (WBI). Negative symptoms, learning and memory performance, processing speed, and executive functioning were related to hours, weeks, and wages earned on the job. Stepwise multiple regression analyses found that among baseline clinical and cognitive predictors, only verbal learning and memory and cognitive disorganization symptoms were significant predictors of work behaviors 4 months later. Learning and memory were the only significant predictors of integrated employment at 4 months. These results suggest specific aspects of cognition may be modestly predictive of vocational outcomes.     

Relationship of Cognition to Clinical Response in First-Episode Schizophrenia Spectrum Disorders

First-episode schizophrenia (FES) spectrum disorders are associated with pronounced cognitive dysfunction across all domains. However, less is known about the course of cognitive functioning, following the first presentation of psychosis, and the relationship of cognition to clinical course during initial treatment. The present longitudinal study examined the magnitude of neurocognitive impairment, using the MATRICS Consensus Cognitive Battery, in patients experiencing their first episode of psychosis at baseline and after 12 weeks of randomized antipsychotic treatment with either aripiprazole or risperidone. At baseline, FES patients evidenced marked impairments in cognitive functioning. Notably, performance on the mazes task of planning and reasoning significantly predicted the likelihood of meeting stringent criteria for positive symptom remission during the first 12 weeks of the trial. Performance on indices of general cognitive function, working memory, and verbal learning improved over time, but these improvements were mediated by improvements in both positive and negative symptoms. We did not detect any differential effects of antipsychotic medication assignment (aripiprazole vs risperidone) on cognitive functioning. Our results suggest that a brief paper-and-pencil measure reflecting planning/reasoning abilities may index responsivity to antipsychotic medication. However, improvements in cognitive functioning over time were related to clinical symptom improvement, reflecting “pseudospecificity.”Key words: cognition, general cognitive function, psychosis, planning, aripiprazole, risperidone     

Temporal relationship between change in cognition and change in functioning in schizophrenia

Most research establishing the relationship between cognition and functioning in schizophrenia has been conducted cross-sectionally, leaving unanswered the question of whether there is a predictive relationship between temporal change in cognition and temporal change in functioning. In the present study, we used longitudinal mixed models to examine the relationship between change in cognition and change in Quality of Life (QLS), as measured over three time-points spanning a 12-month period, for 151 schizophrenia outpatients participating in work therapy with or without cognitive remediation. Memory and executive function changes were significant predictors of improved QLS total. Whereas the relationship between memory and QLS total was in the expected direction, with improvements in memory associated with improvements in QLS, the relationship between executive function and QLS was negative, with QLS improvements associated with declines in executive function. Similar patterns were found for individual QLS domains. Finally, there were positive cross-sectional relationships between QLS and hours worked as well as gender (female gender associated with better QLS). Lag models supported these results. Differences between these findings and previous studies are discussed along with functional assessment issues and the potential moderators of the relationship between cognitive change and functioning.     

Association of estrogen levels with neuropsychological performance in women with schizophrenia.

OBJECTIVE: This study sought to determine the relationship of estrogen levels with psychiatric symptoms and neuropsychological function in female patients with schizophrenia. METHOD: Psychiatric symptoms were assessed and average estrogen and progesterone levels from four consecutive weekly blood samples were measured in 22 female inpatients with schizophrenia who were also administered a neuropsychological battery. RESULTS: There were strong positive correlations between average estrogen level and cognitive function, especially measures of global cognitive function, verbal and spatial declarative memory, and perceptual-motor speed. Correlations of hormone levels with psychiatric symptoms were nonsignificant. CONCLUSIONS: Higher estrogen levels in female patients with schizophrenia are associated with better cognitive ability. These results may have implications for potential treatment of cognitive dysfunction with adjunctive estrogen in female patients with schizophrenia.     

Investigating the neuropsychological and neuroanatomical changes that occur over the first 2-3 years of illness in patients with first-episode schizophrenia

OBJECTIVE: This study explored the concurrent courses of the neuroanatomical and neuropsychological changes that occurred over the first 2-3 years of illness in patients with first-episode schizophrenia (FES). METHODS: Fifty-two patients with FES underwent neuropsychological testing and a structural magnetic resonance imaging (sMRI) scan within three months of their first presentation to mental health services with psychotic symptoms (time1). Patients' cognitive performance was evaluated via an extensive neuropsychological test battery, which assessed 9 cognitive domains. Of the 52 patients at time1, 32 returned 2-3 years later (time2) for follow-up neuropsychological testing, and 20 of these also underwent follow-up sMRI. MR images were preprocessed in SPM99. Grey matter volumes of patients' whole-brain, frontal lobes and temporal lobes were calculated by convolving the preprocessed images with manually-drawn binary masks. RESULTS: Patients exhibited longitudinal improvements in full-scale IQ, performance IQ and visual memory. In contrast, concurrent reductions in grey matter were observed for the whole-brain (3% reduction) and the frontal lobe (3.65% reduction). Furthermore, the extent of patients' whole-brain and frontal-lobe grey matter changes were positively correlated with longitudinal changes in verbal learning and memory. DISCUSSION: The results of this study suggest that while the early stages of schizophrenia are associated with a mild improvement in patients' overall cognitive functioning, they are also associated with progressive grey matter atrophy.     

Cognitive Functioning Predicts Outpatient Service Utilization in Schizophrenia

Aim of the study was to evaluate the cognitive and symptom predictors of outpatient service utilization in schizophrenia. The relationships between cognitive functioning (verbal learning and memory, executive functions), symptoms (positive symptoms, negative symptoms), and outpatient service utilization (case management, medication monitoring), were examined in 20 patients receiving outpatient services at a psychosocial clubhouse over a 12-month period. Executive functions, as measured on the Wisconsin Card Sorting Test (WCST), were the only significant predictor of outpatient service utilization, accounting for over 20% of the variance in total outpatient services used, with greater impairment associated with higher service utilization. Specifically, poorer performance on the WCST was associated with delivery of more case management services, but not medication management services. More case management services may be required to compensate for impairments in executive functioning in patients with schizophrenia.     

Schizophrenia patients with cognitive deficits: factors associated with costs

Cognitive deficits in people with schizophrenia are associated with poor functioning and lower quality of life. Because few studies have examined their relationship with service use or costs, it is unclear whether effective cognitive remediation interventions have potential for economic impacts. This study examined associations between cognition and costs among people with schizophrenia. Baseline data collected between 1999 and 2002 from a randomized controlled trial of cognitive remediation therapy were analyzed. A total of 85 participants were recruited from a London mental health trust if they had a diagnosis of schizophrenia, evidence of cognitive/social functioning difficulties, and at least 1 year since first contact with psychiatric services. Cognition levels, social functioning, symptoms, sociodemographic characteristics, and retrospective use of health/social care and other resources were measured. Average public sector costs were estimated to be 15 078 pounds(23 824 dollars) for a 6-month period. Associations between health/social care costs and type and severity of cognition were examined using structural equation models. No significant relationships were found between cognition and costs in a model based on 3 independent constituent components of cognition (cognitive shifting, verbal working memory, and response inhibition), although a model with covarying cognition components fitted the observed data well. A model with cognition as a single construct both fitted well and showed a significant relationship. In people with schizophrenia and severe cognitive impairment, improvements in either overall cognition or specific cognitive components may impact on costs. Further investigation in larger samples is needed to confirm this finding and to explore its generalizability to those with less severe deficits.     

Donepezil in schizophrenia — is it helpful? An experimental design case study

OBJECTIVE: To assess the clinical and cognitive effects of adding donepezil, a reversible acetylcholinesterase inhibitor, to the risperidone treatment of a high functioning stable out-patient with schizophrenia. METHOD: Case study using an experimental ABAB design. Assessments were completed objectively by standardized neuropsychological tests and clinical rating scales and subjectively with visual analogue scales. RESULTS: Strong improvements attributable to donepezil were found for verbal fluency and the patient's subjective response. No adverse changes were noted in psychiatric symptoms or side effects. CONCLUSION: Cholinergic enhancement as an adjunctive treatment in schizophrenia should be explored in larger controlled trials.     

An open-labeled trial of adjunctive donepezil for cognitive impairments in patients with schizophrenia

A pilot study was conducted to examine if donepezil could enhance cognitive function in patients with schizophrenia. Fifteen subjects who were on stable olanzapine treatment were entered into a 6-week open-labeled trial of donepezil. Subjects received baseline and end-of-study P50 and neuropsychological assessments. Donepezil treatment resulted in significant improvement in manual dexterity. There were moderate improvements in verbal recall memory and visual memory and processing speed, with smaller changes in P50 and verbal recognition memory. There was no effect on an attention measure. There were no changes in either positive or negative symptoms. These results suggest that cholinergic tone modulation may enhance selective behavioral functions in patients with schizophrenia, but further study is required to delineate the full extent of the potential benefit of this approach.     

Gastrointestinal symptoms are predictive of trajectories of cognitive functioning in de novo Parkinson's disease

IntroductionNon-motor symptoms such as cognitive and gastrointestinal (GI) symptoms are common in Parkinson's disease (PD). In PD, GI-symptoms often present prior to motor symptoms. It is hypothesized that GI-symptoms reflect disruptions of the microbiome-gut-brain axis, which leads to altered immune functioning, chronic neuroinflammation, and subsequent neurodegeneration. Initial evidence links gut-dysbiosis to PD pathology and motor symptom severity. The present study examines the longitudinal relationship between severity of GI-symptoms and cognitive impairment in newly diagnosed PD patients.MethodsA secondary data analysis of the Parkinson's Progression Markers Initiative (PPMI) included 423 newly diagnosed PD patients who were followed for up to 5 years. Participants underwent neuropsychological tests of processing speed, attention, visuospatial functioning, verbal learning and verbal delayed recall. Participant were classified as cognitive intact, mild cognitive impairment or Parkinson's disease dementia. Frequency of GI-symptoms were assessed with the Scales for Outcomes in Parkinson's Disease Autonomic (SCOPA-AUT). Multi-level models (MLM) examined the longitudinal relationship between GI symptoms and cognitive impairment.ResultsAll cognitive outcomes were predicted by the main effect of GI symptoms, or the GI-symptom X Occasion interaction term. Specifically, more severe GI-symptoms were predictive of a less favorable trajectory of performance on tests of letter fluency, visuospatial, learning and memory. Cognitive performance was uniquely associated with GI-symptoms and unrelated to non-GI autonomic symptoms.ConclusionsThe presence of GI symptoms may serve as an early marker of cognitive impairment in PD. Future studies should examine specific mechanisms underlying the relationship between gut-dysbiosis and cognitive impairment.     

Effects of olanzapine and other antipsychotics on cognitive function in chronic schizophrenia: a longitudinal study

This study aimed to determine the effect of olanzapine and other antipsychotic drugs on cognitive functions after 6months of treatment. Baseline, 3month and 6month psychopathological and cognitive evaluations were made. Thirty-eight partially responsive outpatients with DSM-IV chronic schizophrenia diagnosis were included in the study. On the indication of their attending psychiatrists, 21 patients initiated treatment with olanzapine, and 17 remained on their previous treatment with other antipsychotic drugs. Cognitive assessments were blind to medication and psychopathological status.The olanzapine group presented a significantly greater improvement in negative symptomatology and verbal memory than the comparison group in repeated-measures of MANOVAs between baseline, 3month and 6month assessments. These differences remained statistically significant after covarying out gender, treatment with other atypical antipsychotics, biperidene doses and changes in positive and negative symptoms. In order to match previous differences between groups, cognitive baseline scores for each test were introduced as covariates, resulting in a significant improvement for the olanzapine group in negative symptomatology and the interference task of the Stroop test.We then re-analyzed the data, dividing the comparison group into two groups: risperidone-treated patients (n=9) and patients receiving conventional antipsychotic drugs (n=8). Post-hoc analyses between groups were carried out with baseline cognitive assessment as covariate. The olanzapine group improved significantly more than the risperidone group in negative symptomatology and in the interference task of Stroop test. The improvement in the number of categories of the Wisconsin Card Sorting Test was higher in risperidone patients than in those receiving olanzapine or conventional antipsychotic treatment. Conventional antipsychotic drugs did not present a significant improvement over atypical antipsychotic drugs in any cognitive function.In summary, in patients suffering from chronic schizophrenia, atypical antipsychotic agents were associated with slight differential improvements over time in attentional, verbal memory and executive functions compared with conventional neuroleptic drugs. No differential improvements were found in social functioning, verbal fluency, non-verbal domains of memory or visuo-motor abilities.