Do the negative symptoms of schizophrenia reflect reduced responsiveness to reward? Examination using a reward prediction error (RPE) task.

BACKGROUND: A leading theory of the negative symptoms of schizophrenia is that they reflect reduced responsiveness to rewarding stimuli. This proposal has been linked to abnormal (reduced) dopamine function in the disorder, because phasic release of dopamine is known to code for reward prediction error (RPE). Nevertheless, few functional imaging studies have examined if patients with negative symptoms show reduced RPE-associated activations. METHODS: Matched groups of DSM-5 schizophrenia patients with high negative symptom scores (HNS, N = 27) or absent negative symptoms (ANS, N = 27) and healthy controls (HC, N = 30) underwent fMRI scanning while they performed a probabilistic monetary reward task designed to generate a measure of RPE. RESULTS: In the HC, whole-brain analysis revealed that RPE was positively associated with activation in the ventral striatum, the putamen, and areas of the lateral prefrontal cortex and orbitofrontal cortex, among other regions. Group comparison revealed no activation differences between the healthy controls and the ANS patients. However, compared to the ANS patients, the HNS patients showed regions of significantly reduced activation in the left ventrolateral and dorsolateral prefrontal cortex, and in the right lingual and fusiform gyrus. HNS and ANS patients showed no activation differences in ventral striatal or midbrain regions-of-interest (ROIs), but the HNS patients showed reduced activation in a left orbitofrontal cortex ROI. CONCLUSIONS: The findings do not suggest that a generalized reduction of RPE signalling underlies negative symptoms. Instead, they point to a more circumscribed dysfunction in the lateral frontal and possibly the orbitofrontal cortex.

Processing of linguistic deixis in people with schizophrenia, with and without auditory verbal hallucinations.

Auditory verbal hallucinations (AVH) are a key symptom of schizophrenia (SZ) defined by anomalous perception of speech. Anomalies of processing external speech stimuli have also been reported in people with AVH, but it is unexplored which specific dimensions of language are processed differently. Using a speech perception task (passive listening), we here targeted the processing of deixis, a key dimension of language governing the contextual anchoring of speech in interpersonal context. We designed naturalistic speech stimuli that were either non-personal and fact-reporting ('low-deixis' condition), or else involved rich deictic devices such as the grammatical first and second persons, direct questions, and vocatives ('high-deixis'). We asked whether neural correlates of deixis obtained with fMRI would distinguish patients with and without frequent hallucinations (AVH + vs AVH-) from controls and each other. Results showed that high-deixis relative to low-deixis was associated with clusters of increased activation in the bilateral middle temporal gyri extending into the temporal poles and the inferior parietal cortex, in all groups. The AVH + and AVH- groups did not differ. When unifying them, the SZ group as a whole showed altered activity in the precuneus, midline regions and inferior parietal cortex. These results fail to confirm deictic processing anomalies specific to patients with AVH, but reveal such anomalies across SZ. Hypoactivation of this network may relate to a cognitive mechanism for attributing and anchoring thought and referential speech content in context.

Trait or state? A longitudinal neuropsychological evaluation and fMRI study in schizoaffective disorder.

Schizoaffective patients can have neurocognitive deficits and default mode network dysfunction while being acutely ill. It remains unclear to what extent these abnormalities persist when they go into clinical remission. Memory and executive function were tested in 22 acutely ill schizoaffective patients; they also underwent fMRI scanning during performance of the n-back working memory test. The same measures were obtained after they had been in remission for ≥ 2 months. Twenty-two matched healthy individuals were also examined. In clinical remission, schizomanic patients showed an improvement of memory but not of executive function, while schizodepressive patients did not change in either domain. All schizoaffective patients in clinical remission showed memory and executive impairment compared to the controls. On fMRI, acutely ill schizomanic patients had reversible frontal hypo-activation when compared to clinical remission, while activation patterns in ill and remitted schizodepressive patients were similar. The whole group of schizoaffective patients in clinical remission showed a failure of de-activation in the medial frontal gyrus compared to the healthy controls. There was evidence for memory improvement and state dependent changes in activation in schizomanic patients across relapse and remission. Medial frontal failure of de-activation in remitted schizoaffective patients, which probably reflects default mode network dysfunction, appears to be a state independent feature of the illness.

Do patients improve after short psychiatric admission?: a cohort study in Italy.

BACKGROUND: Information on outcomes of acute inpatient care in routine psychiatric practice is scant. In particular, it is uncertain to what extent short hospitalization can produce clinically meaningful changes. AIM: Our aim was to estimate the symptomatic outcome in a representative sample of patients admitted for short treatment to general hospital psychiatric units in Italy. METHODS: Patients were assessed at admission and discharge using 24-item Brief Psychiatric Rating Scale (BPRS). Reliable change index was calculated to estimate the proportion of change attributable to measurement error and a cut-off score of 38 was adopted to identify the patients who showed clinically significant change. RESULTS: Average length of stay was 5.7 days. Mean BPRS score dropped from 53.2 on admission to 41.5 at discharge, showing statistically significant improvement with an effect size of 0.80. However, reliable change was achieved by 24.7% of patients and clinically meaningful change by 13.6%. CONCLUSIONS: Reliance on statistical significance and effect size overestimates treatment effects, whereas reliable and clinically significant change index provides a conservative way to assess outcome. Few patients showed relevant improvement after a brief admission.

Olanzapine monotherapy and olanzapine combination therapy in the treatment of mania: 12-week results from the European Mania in Bipolar Longitudinal Evaluation of Medication (EMBLEM) observational study.

BACKGROUND: To evaluate the 12-week outcomes (effectiveness, tolerability, and patterns of medication use) of olanzapine (either in antimanic monotherapy or in combination with other antipsychotics, anticonvulsants, and/or lithium) in patients with bipolar mania or mixed mania. METHOD: EMBLEM (European Mania in Bipolar Longitudinal Evaluation of Medication) is a 24-month prospective observational study of in- and outpatients with acute mania/mixed mania conducted in 14 European countries. Primary outcome measures included Clinical Global Impressions-Bipolar Disorder scale (overall, mania, and depression); 5-item Hamilton Depression Rating Scale; and Young Mania Rating Scale. Tolerability measures included a questionnaire to assess patients' symptomatic complaints. RESULTS: Overall, 2004 patients received olanzapine (olanzapine monotherapy, n=673; olanzapine combination, n=1331). Concomitant therapy with antidepressants and/or anxiolytics was possible in both groups. The countries significantly differed in the use of olanzapine monotherapy versus olanzapine combination (p<.0001). Baseline-to-endpoint changes on the CGI-BP subscales, YMRS, and HAMD-5 were significant within both treatment groups (p<.0001). Olanzapine monotherapy was generally better tolerated than olanzapine combination, particularly with regard to sedation (12% vs 17%; p<.001), tremor (2% vs 5%; p<.001), and akathisia (3% vs 6%; p<.001). DISCUSSION: The acute-phase EMBLEM results suggest that in naturalistic settings, olanzapine (both as monotherapy and combination) may be effective in treating patients with bipolar mania. The use of olanzapine monotherapy or combination varies significantly across countries, but combination is generally the rule, rather than the exception.