Attentional window in schizophrenia and schizotypal personality: Insight from negative priming studies

One of the core deficits that characterizes schizophrenia is an increase in distractibility and disinhibition at all levels of information processing. Patients with schizophrenia seem unable to focus attention on the relevant events while ignoring the irrelevant stimuli. This pattern of behavior is also observed in unmedicated schizotypal individuals who may carry liability for schizophrenia. In this review, we focus on studies of attentional inhibition, as assessed by the negative priming paradigm, to elucidate the relationships among deficits in inhibition, clinical symptoms and medication effects. We then consider models of the etiology of deficits in negative priming in schizophrenia and schizotypal personality. Finally, we discuss the potential power of utilizing hypothesis-driven cognitive paradigms in psychiatric research.     

Neuropsychological profile in patients with schizotypal personality disorder or schizophrenia

Neuropsychological impairments have been consistently reported in patients with schizophrenia. As little is known whether subjects with schizotypal personality disorder exhibit neurocognitive dysfunction similar to that in schizophrenia, we assessed the neuropsychological profile of 15 subjects with schizotypal personality disorder and compared it with that for 15 patients with schizophrenia and for 15 psychiatrically normal volunteers. All participants were administered a standard neuropsychological battery assessing language ability, spatial ability, visuomotor function, verbal memory, visual memory, auditory attention, visual attention, and executive function. Performance on most of the cognitive domains was impaired in patients with schizotypal personality disorder but less than patients with schizophrenia. Specifically, impairment in verbal memory and visuomotor ability in patients with schizotypal personality disorder and patients with schizophrenia were comparable, while patients with schizophrenia performed worse on the test of executive function than did patients with schizotypal personality disorder. As a whole, cognitive deficits in patients with schizotypal personality disorder were qualitatively similar to, but quantitatively milder than, those for patients with schizophrenia. The results suggest that cognitive abilities related to frontotemporal lobe function are disturbed across these schizophrenia-spectrum disorders.     

Schizotypal personality traits and atypical lateralization in motor and language functions

Atypical cerebral lateralization in motor and language functions in regard to schizotypal personality traits in healthy populations, as well as among schizophrenic patients, has attracted attention because these traits may represent a risk factor for schizophrenia. Although the relationship between handedness and schizotypal personality has been widely examined, few studies have adopted an experimental approach. This study consisted of three experiments focusing on motor and language functional lateralization in regard to schizotypal personality in the absence of mental illness: line-drawing, finger tapping, and a semantic go/no-go task. The results suggested that positive schizotypal personality might be related to functional non-lateralization in regard to at least some functions (e.g., spatial motor control and semantic processing in the present study). Subjects with high schizotypal personality traits performed equally with their right and left-hands in the line-drawing task and they reacted equally with their right and left-hands in a semantic go/no-go task involving semantic auditory stimuli presented in both ears. However, those low in schizotypal personality traits showed typical lateralization in response to these tasks. We discuss the implications of these findings for schizotypal atypical lateralization.     

Trauma,personality disorders and chronic depression – the role of the conversational model of psychodynamic psychotherapy in treatment resistant depression

Objective: To report preliminary data describing the interim treatment outcome of 44 patients referred with treatment-resistant depression (TRD), comorbid personality disorders and histories of early childhood trauma using the Conversational Model (CM) of psychodynamic psychotherapy. Method: Patients (N = 44), 13 males and 31 females with long histories of depression ranging from 2 to 30 years, resistant to multiple trials of treatment, were referred by mental health practitioners, including psychiatrists. They were treated with twice weekly CM psychotherapy by multidisciplinary trainees and supervised by experienced trained clinicians. Questionnaires were administered at assessment and at 12 months to assess symptoms, functioning, self-esteem, history of trauma, personality functioning and suicidality. In this preliminary study, there was no separate control group, and patients served as their own controls. Results: Patients with TRD were found to have comorbid severe personality disorders and histories of early childhood trauma. Significant improvement in symptoms, self-esteem, functioning and suicidality was noted after 12 months. Conclusion: Patients responded with symptomatic and functional improvement to twice weekly CM therapy.     

Smooth pursuit eye movement and schizotypy in the community

Deficits in smooth pursuit eye movements are well documented in schizophrenia and schizotypic psychopathology. The status of eye tracking dysfunction (ETD) as an endophenotype for schizophrenia liability is relatively robust. However, the relation of ETD to schizophrenia-related deviance in the general population has not been confirmed. This study examined smooth pursuit eye tracking and schizotypal personality features in the general population. Smooth pursuit eye movement and schizotypal features were measured in 300 adult community subjects. The sample included both sexes, subjects with a wide age and educational range, and subjects with no prior history of psychosis. Primary outcome measures were peak gain (eye velocity/target velocity), catch-up saccade rate, and schizotypal feature scores. Total schizotypal features were significantly associated with decreased peak gain and were associated at the trend level with increased catch-up saccade rate. These associations were essentially unchanged after controlling for age, sex, and intellectual level effects. These data confirm a hypothesized association between schizotypal features and poorer eye tracking performance (principally, peak gain) in the general population as well as support the conceptualization of ETD as an endophenotype for schizophrenia liability.     

Lateralized perceptual organization deficits on the global-local task in schizotypal personality disorder

Right and left hemisphere contributions to perceptual organization functions were examined using a divided-attention version of the global-local task in a sample of 21 unmedicated participants diagnosed with schizotypal personality disorder (SPD) and 20 controls. The SPD participants showed an abnormal global processing advantage. When the visual angle of the hierarchical stimuli was increased from 3 degrees to 9 degrees, the controls showed an increasing local processing advantage, but the SPD participants continued to show an abnormal global processing advantage. These findings suggest a local processing deficit on divided-attention versions of the global-local task in schizophrenia spectrum disorders. Female SPD participants, who had less severe interpersonal deficit symptoms, showed a more abnormal global processing advantage. Hemispheric and processing resource mechanisms that might explain these findings are discussed.     

Personality features and cognitive level in patients at an early stage of Alzheimer’s disease

In this cross-sectional study, we explored the relationship between premorbid personality and its changes over 5 years, and cognitive deterioration in patients with mild Alzheimer’s disease. The cognitive level of 54 patients was compared with that of 64 control subjects using the Mini Mental State (MMSE). Family members completed the NEO-PI-R (form R) twice, once to evaluate the participants’ current personality and again to assess personality traits as they were remembered to be 5 years earlier. Furthermore, the family filled in the Informant Questionnaire on Cognitive Decline (IQCODE), the Activities of Daily Living (ADL), and the Instrumental Activities of Daily Living (IADL) scales to assess their proxies’ cognitive level and daily living functioning. Regarding the relationship between personality characteristics and cognitive status, we observed trends for premorbid personality and significant links for personality changes in the clinical group. Thus, changes in neuroticism and conscientiousness were associated with cognitive deterioration, whereas decreased openness to experience and conscientiousness over time predicted loss of independence in daily functioning in the clinical group. Our study suggests that premorbid features can be considered as latent traits linked to the neuropathology underlying the disease process, while personality changes are probably the consequences of the pathological process.     

Sex differences in schizotypal personality in a nonclinical population.

This study tests the hypothesis that normal women will score higher on the more "positive" features of schizotypal personality and normal men will score higher on more "negative" schizotypal features. Two samples (n = 393, 394) were administered the Schizotypal Personality Questionnaire, which contains subscales corresponding to the 9 schizotypal personality traits outlined in the Diagnostic and Statistical Manual of Mental Disorders (rev. 3rd ed.; American Psychiatric Association, 1987). Women scored significantly higher on the positive subscales of Ideas of Reference and Odd Beliefs/Magical Thinking, and men scored significantly higher on the negative subscales of No Close Friends and Constricted Affect. These findings replicated from one sample to another. These results are broadly consistent with previous findings on schizotypal personality and schizophrenia. It is hypothesized that sex differences in schizophrenic symptomatology may in part reflect an exaggeration of normal sex differences in the general population.     

The use of the Ego Impairment Index across the schizophrenia spectrum

The goal of this study was to assess perceptual and thought disturbance, as indexed by the Ego Impairment Index (EII; Perry & Viglione, 1991), a Rorschach-derived measure, across the schizophrenia spectrum. We hypothesized that there would be an increase in EII scores (indicating increased disturbance) across the spectrum from nonpatients to severely disturbed, hospitalized schizophrenia patients. Normal comparison participants (n = 66), students with elevated scores on either the Perceptual Aberration/Magical Ideation or the Physical Anhedonia Scales (n = 24), first-degree relatives of schizophrenia patients (n = 36), participants diagnosed with Diagnostic and Statistical Manual of Mental Disorders (4th ed. [DSM-IV]; American Psychiatric Association, 1994) schizotypal personality disorder (n = 36), outpatient schizophrenia participants (n = 33), and hospitalized schizophrenia patients (n = 56) were studied. As hypothesized, we found increased EII scores in all of the schizophrenia spectrum groups when compared against normal comparison participants. Furthermore, the EII was significantly different between the schizophrenia patients and the other schizophrenia spectrum groups. These findings support the use of the EII as a sensitive measure of perceptual and thought disturbance across the schizophrenia spectrum that yields specific information regarding the type of thinking problems that occur within schizophrenia spectrum subgroups.     

Mentalising, schizotypy, and schizophrenia.

Despite accumulating evidence that patients with schizophrenia perform poorly in mentalising tasks, doubts remain about the primacy of the role played by defective mentalising in schizophrenia. This study investigated the relationship between mentalising ability and self-reported schizotypal traits in non-clinical adults who reported no history of psychiatric illness in order to test two counter-proposals: (1) defective mentalising is a primary cause of psychotic symptoms in schizophrenia; and (2) defective mentalising in schizophrenia is a secondary consequence of the chronic asociality that is typical of general psychiatric illness. Mentalising ability was tested using a false-belief picture sequencing task that has been used elsewhere to demonstrate poor mentalising in patients with schizophrenia. Evidence of selective mentalising deficits in high schizotypal non-clinical subjects discounted the view that defective mentalising is restricted to psychiatric illness and strengthened the case for continuity models of psychosis-proneness. Furthermore, evidence that poor mentalisers in the normal population are more likely to self-report psychotic-like traits, as well as asocial or idiosyncratic behaviours, refuted suggestions that defective mentalising is linked solely to asocial symptomatology and supported the view that defective mentalising may have a fundamental role to play in the explanation of psychotic symptoms. In order to specify what that role might be, alternative theoretical accounts of defective mentalising were tested. Neither executive planning deficits nor failure to inhibit cognitively salient inappropriate information could adequately explain the pattern of selective mentalising deficits found in high schizotypal non-clinical subjects. Our findings suggest that there exists a domain-specific cognitive module that is dedicated to inferring and representing mental states which, when dysfunctional, causes defective mentalising that manifests phenomenologically in psychotic-like traits and impoverished social awareness of variable expression and ranging severity.     

Demographic, clinical, and neurocognitive correlates of everyday functional impairment in severe mental illness

Although cognitive deficits often accompany severe mental illness, their implications for everyday functioning remain poorly understood. In this study, an occupational therapist (OT) rated the everyday functioning of 105 adult psychiatric patients. Using demographic, clinical, and cognitive variables, the authors tested alternative models to account for the observed variability in OT ratings. Although age, education, and the presence of schizophrenia each contributed to a model that accounted for 27% of the variation in functional independence, adding terms for auditory divided attention and verbal learning increased the proportion of explained variance to 45% and decreased the beta weights for age and education--but not schizophrenia--to nonsignificant levels. These findings demonstrate the relevance of cognitive performance to everyday functioning in severe mental illness. They are discussed with respect to hypothesized determinants of psychiatric disability.     

Social skills and sex-role functioning in borderline personality disorder: relationship to self-mutilating behavior

This study compared the social skills functioning and sex role affiliation of female inpatients diagnosed with borderline personality disorder who engaged in self-mutilating behavior (n = 30) with female patients with borderline personality disorder who did not engage in such behavior (n = 18). Patients with borderline personality disorder who engaged in self-mutilating behavior were found to have relatively poorer skills in communicating non-verbal emotional information to others and in receiving and interpreting such information from others. In terms of sex role orientation, patients who engaged in self-mutilating behavior were significantly more likely than non-mutilators to be typed as undifferentiated using the Bem Sex Role Inventory. These participants were less likely to identify with either masculine or feminine sex roles. Patients who did not self-mutilate were found to be significantly more likely than those who did self-mutilate to identify with the masculine sex role.     

Social anxiety and premorbid personality disorders in paranoid schizophrenic patients treated with clozapine

The concept of anxiety as a distinct comorbid disorder in schizophrenia has recently been rediscovered after having been neglected for a long period of time due to both theoretical and clinical approaches adopted from the appearance of the first edition of the Diagnostic and Statistical Manual of Mental Disorders in 1950. This rediscovery was accentuated by the fact that the concept of comorbidity in various psychiatric disorders has recently won widespread favor within the scientific community, and that the use of atypical neuroleptic medication to treat patients with schizophrenia has been reported to lead to the emergence of anxiety symptoms. Of the atypical neuroleptic medications used to treat schizophrenia, clozapine has most frequently been reported to induce anxiety symptoms. In this paper, 12 cases of patients with paranoid schizophrenia who developed social phobia during clozapine treatment are reported, and their response to fluoxetine augmentation is assessed. Premorbid personality disorders were also investigated; patients were assessed using the Structured Clinical Interview for DSM-III-R-Patient Version and the Structured Clinical Interview for DSM-IV Axis II Personality Disorders (DSM-III-R=Diagnostic and Statistical Manual of Mental Disorders, Third Edition Revised; DSM-IV=Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition). In addition, the Scale for the Assessment of Negative Symptoms, the Scale for the Assessment of Positive Symptoms, the Liebowitz Social Anxiety Scale (LSAS), the Frankfurt Beschwerde Fragebogen (Frankfurt Questionnaire of Complaints), and the Brief Psychiatric Rating Scale were used to rate clinical symptomatology. All patients were reevaluated after 12 weeks of cotreatment with clozapine and fluoxetine. In 8 (66.6%) of the 12 cases, symptoms responded (>/=35% LSAS score reduction) to an adjunctive regimen of fluoxetine. Furthermore, in 7 (58.3%) of the 12 cases, an anxious personality disorder (avoidant=33.3%; dependent=25%) was identified, but no significant differences in the prevalence of comorbid personality disorders emerged in comparison with a group of 16 patients with paranoid schizophrenia treated with clozapine who did not show symptoms of social phobia. The clinical relevance of the assessment and treatment of anxiety disorders is discussed in light of a clinical therapeutic approach that overcomes the implicit hierarchy of classification. Considering that the onset of anxiety-spectrum disorders (such as social phobia) can occur during the remission of psychotic symptoms in clozapine-treated patients with schizophrenia, a comprehensive approach to pharmacological therapy for patients with schizophrenia (or, at least for those treated with clozapine) should be adopted.     

Positive schizotypal symptoms predict treatment outcome in obsessive-compulsive disorder

Previous research has suggested that the presence of schizotypal personality disorder may represent a risk factor for treatment failure in obsessive-compulsive disorder (OCD). Relying on a dimensional approach, the present study investigated whether the predictive importance of schizotypal personality is shared by all of its features to the same extent or whether it is confined to a subset of symptoms. Fifty-three patients underwent multi-modal cognitive-behavioral therapy with or without adjunctive antidepressive medication. Therapy response was defined as a 35% decline of the Y-BOCS total score. At baseline assessment, patients were asked to fill out the schizotypal personality questionnaire, the perceptual aberration scale and the Beck depression inventory. Stepwise regression analysis and group comparisons conducted with the schizotypal and depression scales revealed that elevated scores in the positive schizotypal scales, especially perceptual aberrations, were highly predictive for treatment failure. Responders to treatment and non-responders did not significantly differ on other variables or on scores in two scales which measured response biases. The study provides evidence that positive schizotypal symptoms are antecendents for treatment failure in OCD. It needs to be evaluated whether these at-risk individuals benefit from additional intervention, such as the adminstration of low-dose atypical neuroleptics and specifically tailored behavorial intervention.     

Dimensions of DSM-IV personality disorders and life-success

This study examined associations between dimensional representations of DSM-IV personality disorders and life-success in a community sample of 304 men at age 48. Measures included a standardized social interview and the SCID-II for assessment of personality disorders. The identified indicators of life-success were factor-analyzed resulting in two moderately correlated components representing "status and wealth" and "successful intimate relationships." Avoidant, obsessivecompulsive, and narcissistic dimensional scores were positively associated with "status and wealth." Inverse relationships were found between dependent, schizotypal, schizoid, and adult antisocial personality disorder dimensions and this domain of life-success. Avoidant, schizoid, and borderline personality disorder dimensions were negatively associated with "successful intimate relationships." The findings suggest that although most personality disorders are associated with impaired psychosocial functioning and life-failure, some personality disorder traits (even if considered as pathological) can contribute positively to one important aspect of life-success: status and wealth.     

An investigation of schizotypy in injecting amphetamine users

A fully dimensional view of psychiatric disorder conceptualises schizotypy as both a continuous personality trait and an underlying vulnerability to the development of psychotic illness. Such a model would predict that the structure of schizotypal traits would closely parallel the structure of schizophrenia or psychosis. This was investigated in injecting amphetamine users (N = 322), a clinical population who have high rates of acute psychotic episodes and subclinical schizotypal experiences. Schizotypy was assessed using the Oxford-Liverpool Inventory of Feelings and Experiences (O-LIFE), and psychotic symptoms were assessed using the Brief Psychiatric Rating Scale (BPRS). Using confirmatory factor analysis, O-LIFE subscale scores were mapped onto latent variables with their more clinical counterparts from the BPRS. A four-factor model comprising positive schizotypy, disorganisation, negative schizotypy, and disinhibition provided the best model fit, consistent with prior research into the structure of schizotypy. The model provided a good fit to the data, lending support to the theory that schizotypy and psychotic symptoms map onto common underlying dimensions.     

Schizotypy and pathological personality profile in siblings of patients with psychosis

Schizotypy has been proposed to be the expression of the genetic vulnerability to schizophrenia. Schizotypal features have been associated with personality dimensions found in patients with psychosis. In this study, we compared the Dimensional Assessment of Personality Pathology - Basic Questionnaire (DAPP-BQ) scores of patients with psychosis, siblings scoring higher on schizotypy (SSHS), and siblings scoring lower (SSLS). The SSHSs displayed a DAPP-BQ profile characterized by high scores in the dimensions of affective lability, anxiousness, submissiveness, social avoidance, identity problems, oppositionality, narcissism, and restricted expression, distinguishing them from the SSLS. Due to these dimensions, SSHSs are more similar to the patients' DAPP-BQ profile. The results suggest that this pathological personality profile might contribute to increase the risk of developing psychosis in siblings who have more schizotypal features.     

Body language reading of emotion in schizophrenia: Associations with symptoms and functional outcome

Our aim was to explore how body language reading of emotion relates to neurocognition, symptoms and functional outcome in schizophrenia. Fifty‐four individuals with schizophrenia and eighty‐four healthy controls participated in the study. Emotion perception was assessed with a point‐light display (PLD) task, the Emotion in Biological Motion (EmoBio) test, neurocognition was measured with the MATRICS Consensus Cognitive Battery (MCCB), and functioning was indexed by one measure of functional capacity and by one self‐report questionnaire. Clinical symptoms were assessed with a five factor Positive and Negative Syndrome Scale (PANSS) symptoms model. Participants with schizophrenia had impaired body language reading of emotions compared to healthy controls (Cohen's d = 0.69). In participants with schizophrenia, emotion perception was associated with neurocognition (r = 0.42), functional capacity (r = 0.27) and disorganization symptoms (r = –0.27). Mediation analyses showed that disorganization symptoms mediated the effects of emotion perception and neurocognition, respectively, on social functional capacity. These results suggest that in individuals with schizophrenia, reduced emotion perception from body movements has negative consequences for functional outcome, but that the effect is mediated through disorganization symptoms.