MISATTRIBUTION OF EMOTIONAL OVER-AROUSAL TO NEUTRAL FACES IN ACUTE PARANOID SCHIZOPHRENIA PSYCHOSIS.

INTRODUCTION: Misattribution of motivational salience to non-salient (neutral) stimuli could be viewed as a hallmark of psychosis in schizophrenia. Studies have recently revealed increased subjective experience of emotional arousal (EA) to neutral social stimuli in paranoid schizophrenia psychosis, suggesting a misattribution of emotional salience to them. We examined this phenomenon directly by quantifying the level of EA subjectively attributed to low-arousal, neutral-valenced faces. SUBJECTS AND METHODS: A task for EA attribution to neutral (in the context of affective) facial expressions was applied to 44 actively psychotic paranoid schizophrenia inpatients and 44 well-matched healthy controls. RESULTS: Psychotic patients, compared with healthy controls, rated the neutral faces as more aroused (t (86) = 3.15, p =.001) thus misattributing emotional salience to them. DISCUSSION: This finding supports the hypothesis that over-assignment of EA to neutral faces could be viewed as a subclinical affective mechanism of the clinically manifested experience of delusional perception. CONCLUSION: The study provides the first direct empirical evidence for misattribution of emotional salience in terms of over-attribution of EA to neutral faces during acute paranoid schizophrenia psychosis.

Objective and quantitative equilibriometric evaluation of individual locomotor behaviour in schizophrenia: Translational and clinical implications.

Psychiatry is the only medical specialty that lacks clinically applicable biomarkers for objective evaluation of the existing pathology at a single-patient level. On the basis of an original translational equilibriometric method for evaluation of movement patterns, we have introduced in the everyday clinical practice of psychiatry an easy-to-perform computerized objective quantification of the individual locomotor behaviour during execution of the Unterberger stepping test. For the last 20 years, we have gradually collected a large database of more than 1000 schizophrenic patients, their relatives, and matched psychiatric, neurological, and healthy controls via cross-sectional and longitudinal investigations. Comparative analyses revealed transdiagnostic locomotor similarities among schizophrenic patients, high-risk schizotaxic individuals, and neurological patients with multiple sclerosis and cerebellar ataxia, thus suggesting common underlying brain mechanisms. In parallel, intradiagnostic dissimilarities were revealed, which allow to separate out subclinical locomotor subgroups within the diagnostic categories. Prototypical qualitative (dysmetric and ataxic) locomotor abnormalities in schizophrenic patients were differentiated from 2 atypical quantitative ones, manifested as either hypolocomotion or hyperlocomotion. Theoretical analyses suggested that these 3 subtypes of locomotor abnormalities could be conceived as objectively measurable biomarkers of 3 schizophrenic subgroups with dissimilar brain mechanisms, which require different treatment strategies. Analogies with the prominent role of locomotor measures in some well-known animal models of mental disorders advocate for a promising objective translational research in the so far over-subjective field of psychiatry. Distinctions among prototypical, atypical, and diagnostic biomarkers, as well as between neuromotor and psychomotor locomotor abnormalities, are discussed. Conclusions are drawn about the translational and clinical implications of the new approach and its future perspectives.