Disturbances of spontaneous empathic processing relate with the severity of the negative symptoms in patients with schizophrenia: a behavioural pilot-study using virtual reality technology.

Behavioural and neuroimaging data have recently pointed out that empathy (feeling into someone else) is associated with mental imagery and transformation related to one's and other's visuo-spatial perspectives. Impairments of both empathic and visuo-spatial abilities have been observed in patients with schizophrenia. Especially, it has been suggested that schizophrenics are altered in spontaneously simulating another individual's first-person experience. However, there is so far only little evidence regarding the relationship between deficits in empathy and disturbances in spontaneous heterocentered coding in schizophrenia. In the present pilot-study, we tested with schizophrenic patients our behavioural paradigm that enables to measure from the bodily postures and movements whether individuals in ecologically more valid conditions are interacting with another individual by using egocentered - as in sympathy (feeling with someone else) - or heterocentered - as in empathy - visuo-spatial mechanisms. For that, ten patients and ten controls, standing and moving, interacted with a virtual tightrope walker, displayed life-sized, standing and moving as well. We show that patients with higher negative symptoms had, in most cases, deficits in spontaneously using heterocentered visuo-spatial mechanisms and employed preferentially an egocentered referencing to interact with the avatar. In contrast, preserved spontaneous heterocentered visuo-spatial strategies were not linked to a prevailing negative or positive symptomatology. Our data suggest that the severity of the negative symptoms in schizophrenia relates with disturbances of spontaneous ("on-line") empathic processing in association with lower scoring self-reported trait cognitive empathy.

Inverse relationship between thalamic and orbitofrontal volumes in obsessive-compulsive disorder.

Volumetric magnetic resonance imaging (MRI) studies in obsessive-compulsive disorder (OCD) have reported a smaller volume of the orbitofrontal cortex (OFC) and a larger volume of the thalamus compared with healthy controls. Both of these brain regions are strongly connected; therefore, it may be hypothesized that cortical and thalamic alterations are related. Here, we investigated the relationship between thalamic and orbitofrontal volumes in OCD patients relative to healthy controls. MRI volumetric measurements of the thalamus and the OFC were obtained in 16 OCD patients without comorbidity and 16 comparison subjects matched for age, sex and educational level. Partial correlation analyses that controlled for intracranial volume (ICV) were performed to explore relationships between thalamic and OFC volumes in each group. In order to assess the specificity of this relationship, we conducted similar analyses of the anterior cingulate cortex (ACC) as a non-OFC cortical volume. Finally, by using data from previously published volumetric MRI studies, we conducted a meta-regression to explore the relationships between volume changes in these regions of interest. Results showed that thalamic volumes were significantly negatively correlated with OFC volumes in OCD patients (r=-0.83, p<0.001), but not in healthy subjects (r=-0.15, p=0.59). A significant relationship between thalamic and ACC volumes was found neither in the OCD patients (r=0.03, p=0.91) nor in the comparison subjects (r=-0.23, p=0.40). Furthermore, meta-regression analyses showed that previously reported volume changes in the thalamus were significantly correlated with OFC volume changes (r=-0.71, p<0.05), but not with ACC volume changes (r=0.07, p=0.86). Although our results do not allow for any causal relationship to be established, they suggest that structural alterations of both the thalamus and the OFC are inversely and specifically related in OCD.

Subthalamic nucleus stimulation in severe obsessive-compulsive disorder.

BACKGROUND: Severe, refractory obsessive-compulsive disorder (OCD) is a disabling condition. Stimulation of the subthalamic nucleus, a procedure that is already validated for the treatment of movement disorders, has been proposed as a therapeutic option. METHODS: In this 10-month, crossover, double-blind, multicenter study assessing the efficacy and safety of stimulation of the subthalamic nucleus, we randomly assigned eight patients with highly refractory OCD to undergo active stimulation of the subthalamic nucleus followed by sham stimulation and eight to undergo sham stimulation followed by active stimulation. The primary outcome measure was the severity of OCD, as assessed by the Yale-Brown Obsessive Compulsive Scale (Y-BOCS), at the end of two 3-month periods. General psychopathologic findings, functioning, and tolerance were assessed with the use of standardized psychiatric scales, the Global Assessment of Functioning (GAF) scale, and neuropsychological tests. RESULTS: After active stimulation of the subthalamic nucleus, the Y-BOCS score (on a scale from 0 to 40, with lower scores indicating less severe symptoms) was significantly lower than the score after sham stimulation (mean [+/-SD], 19+/-8 vs. 28+/-7; P=0.01), and the GAF score (on a scale from 1 to 90, with higher scores indicating higher levels of functioning) was significantly higher (56+/-14 vs. 43+/-8, P=0.005). The ratings of neuropsychological measures, depression, and anxiety were not modified by stimulation. There were 15 serious adverse events overall, including 1 intracerebral hemorrhage and 2 infections; there were also 23 nonserious adverse events. CONCLUSIONS: These preliminary findings suggest that stimulation of the subthalamic nucleus may reduce the symptoms of severe forms of OCD but is associated with a substantial risk of serious adverse events. (ClinicalTrials.gov number, NCT00169377.)