Exploring neurophysiological markers of visual perspective taking: Methodological considerations.

RATIONALE: For visual perspective taking (VPT) using the avatar task, examinations of neural processes using event related potentials (ERP) indicate a distinction between an early posterior perspective calculation process (P3) and a later frontal process (LFSW) managing perspective conflict. While it is unknown if these neural processes are affected in clinical populations, it is unclear if the avatar task can be applied to this group, due to the long duration and sensitivity to data loss. Thus, we performed a methodological study of the avatar task, testing the feasibility of a shortened experimental paradigm. OBJECTIVE: To investigate whether previously reported behavioural and ERP effects in the avatar task can also be seen if analysing all trials (matching/non-matching) jointly, and whether they remain robust if only a subset of the data is analysed. METHOD: Healthy individuals (n = 20) completed the avatar task with ERP measurement. ERP components (P3, LFSW) and behavioural data were investigated by A) comparing use of only matching trials (n = 384) versus all trials (n = 768), and B) examining if reduced duration of assessment, by analysing only a subset of the data, impacts ERP findings. RESULTS: We observed minimal differences when analysing data from only matching trial types compared to all trial types. Further, ERP amplitudes and latency findings were replicated when analysing only a subset of the data. CONCLUSIONS: The duration of the avatar task can be reduced to avoid long testing times, thus making it better suited for use in clinical populations.

Cardiac left ventricular ejection fraction in men and women with schizophrenia on long-term antipsychotic treatment.

Patients with schizophrenia exhibit a higher cardiovascular mortality compared to the general population which has been attributed to life-style factors, genetic susceptibility and antipsychotic medication. Recent echocardiographic studies have pointed to an association between clozapine treatment and reduced left ventricular ejection fraction (LVEF), a measure that has been inversely associated with adverse outcomes including all-cause mortality. Cardiovascular magnetic resonance (CMR) is considered the reference method for LVEF measurement. The aim of the present study was to investigate the LVEF in patients with schizophrenia on long-term treatment with antipsychotics and healthy controls. Twenty-nine adult patients with schizophrenia on long-term medication with antipsychotics and 27 age-, sex- and body mass index-matched healthy controls (mean ages 44 and 45 years, respectively) were recruited from outpatient psychiatric clinics in Uppsala, Sweden. The participants were interviewed and underwent physical examination, biochemical analyses, electrocardiogram and CMR. Men with schizophrenia on long-term antipsychotic treatment showed significantly lower LVEF than controls (p = 0.0076), whereas no such difference was evident among women (p = 0.44). Specifically, clozapine-treated male patients had 10.6% lower LVEF than male controls (p = 0.0064), whereas the LVEF was 5.5% below that of controls among male patients treated with non-clozapine antipsychotics (p = 0.047). Among medicated men with schizophrenia, we found significantly lower LVEF compared to healthy individuals, suggesting the need of routine cardiac monitoring in this patient group. This is the first study showing a significant negative association between treatment with non-clozapine antipsychotics and LVEF.

Neurocognitive function in long-term treated schizophrenia: a five-year follow-up study.

Neurocognitive deficits are a core feature of schizophrenia. Deficits covering a wide range of functions have been well documented. However there is still a lack of longitudinal studies regarding the development of neurocognitive impairment. The current study examined the effect of time in long-term treated patients with schizophrenia and healthy controls on cognitive functions. A neurocognitive test-battery was administered to 36 patients and 46 controls on two occasions with approximately 4.5 years interval. Patients performed significantly worse on all measures on both occasions. The only significant decline over time was the ability to shift mental set between different rules or categories (measured by Trail Making Test B). This decline was present in both patients and controls. Improvement on attention (tested by Continuous Performance Test) was found in patients only and improvement on verbal learning (tested by Rey Auditory Verbal Learning Test) was found only in controls. Education was significantly related to outcome in patients and age was related to outcome in controls. We conclude that neurocognitive function is relatively stable over 4.5 years in patients with long-term treated schizophrenia, in line with previous scientific research. The authors discuss the impact of age and education and limitations of the study.