The self-other distinction network in patients with schizophrenia, compared with healthy controls.

<p>In the middle column, the red-to-yellow colour-code represents the relative percentage of subjects with greater activity in the [EGV – SGV] contrast, after we performed cortex-based normalization between the healthy matched controls (CTL) and the patients suffering from schizophrenia (SCZ). %PM: percentage of activity in the subjects included at a specific spatial location, in a range from 20 to 90 (spatial consistency). In the patients, the difference in the [EGV – SGV] contrast was significantly less marked than for the controls, which was also confirmed by the mean haemodynamic response of the fMRI signal in the right inferior parietal lobule (IPL). This is shown for each group in the left panel. The green bars represent the EGV condition, and the red bars show the SGV condition. In the right column, correlation analysis (adjusted for the dosage of the antipsychotic drugs) between the intensity of the fMRI signal in the self-other distinction network and the severity of the positive symptoms in schizophrenia (PANSS positive subscale) is shown.</p

Demographic information of the participants included in the ‘implicit self-other distinction’ study (n = 30).

<p><i>The z-scores shown in this table come from the Wilcoxon non-parametric test; sd: standard deviation; ; Yrs: years; NA: not applicable; NS: not significant; M: male, F: female subjects; R: right; L: left; CPZ-Eq: daily therapeutic equivalent dose for the antipsychotic medications, using Chlorpromazine as a reference</i>.</p

Cortical areas involved in implicit self-other distinction in healthy controls and patients with schizophrenia.

<p>BA: Brodmann's areas; R/L: right or left side of the brain; SMA: supplementary motor area.</p

Diagram of the fMRI block-design with the expected results.

<p>In the upper left panel, a model of each experimental condition is shown: RTV (reverse-tape voice: yellow), EGV (externally-generated voice: green) and SGV (self-generated voice: red). Each block lasted 21 sec. and was repeated 8 times in a random order, each time being followed by a 12 sec. silent period. Part of the recorded voice spectrogram is shown in detail, as an example of the SGV condition, preceded by a 500 msec. high-pitched cue, which indicated that the subject had to mentally repeat what he was hearing (covert speech). The other conditions [EGV, SGV] were preceded by low-pitched cues, indicating that the subject should listen passively. Two contrast analyses were performed, and are shown in the right panel of the figure. C1 contrasted EGV and RTV, and revealing brain areas from the Mirror-Neuron-System. C2 contrasted EGV with SGV and revealed the cortical network involved in self-other distinction. The middle column shows known results from healthy subjects for C1 and C2 <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0017500#pone.0017500-Jardri1" target="_blank">[17]</a>. The right column lists the expected results in the patients with schizophrenia for the C1 and C2 contrasts. In our study, we hypothesized that in schizophrenics, there would be more overlap between the neural networks activated for representation of other or self (C2). This result cannot be explained by dysfunction in the mirror neuron system (C1). IFG: Inferior Frontal Gyrus/IPL: Inferior Parietal Lobule/ACC: Anterior Cingulate Cortex/PCC: Posterior Cingulate Cortex/STS: Superior Temporal Sulcus/SMA: Supplementary Motor Area/R-L: Right or left side of the brain, respectively.</p

Cortico-striatal fibre tracts in one healthy subject and one HD patient.

<p>Only 1% of the actual fibre tracts were randomly selected and represented for a better rendering. In the patient, the volume of the striatum was reduced and the number of tracts obtained for each nucleus was decreased.</p

Connectivity profile of the striatum to the cortex.

<p>(A) Average connectivity measures per surface unit for each nucleus and each gyrus. (B) Cortical gyri constituting the connectivity profile of each nucleus.</p

Volumes of the deep nuclei for healthy subjects and HD patients.

<p>Points represent mean values and bars standard deviations.</p

Percentage difference of connectivity for the striatum nuclei.

<p>The figure shows the percentage difference of connectivity between healthy subjects and HD patients, obtained for each nucleus of the striatum and cortical gyri belonging to the connectivity profile of the nucleus and presenting a significant connectivity difference between healthy subjects and HD patients.</p

Clinical characteristics of the subjects.

<p>Clinical characteristics of the subjects.</p

Selection of the connections of the striatum for a healthy subject.

<p>(A) selection of the tracts that intersect the striatum, (B) selection of only the direct tracts that link the striatum to the cortex. Only 1% of the actual fibre tracts were randomly selected and represented for a better rendering.</p