In patients with schizophrenia in a psychotic episode, intra-striatal intrinsic connectivity is increased in the putamen but not ventral striatum. Furthermore, multimodal changes have been observed in the anterior insula that interact extensively with the putamen.

We hypothesised that during psychosis, putamen extra-striatal functional connectivity is altered with both the anterior insula and areas normally connected with the ventral striatum (i.e. altered functional connectivity distinctiveness of putamen and ventral striatum).

We acquired resting-state functional magnetic resonance images from 21 patients with schizophrenia in a psychotic episode and 42 controls.

Patients had decreased functional connectivity: the putamen with right anterior insula and dorsal prefrontal cortex, the ventral striatum with left anterior insula. Decreased functional connectivity between putamen and right anterior insula was specifically associated with patients' hallucinations. Functional connectivity distinctiveness was impaired only for the putamen.

Results indicate aberrant extra-striatal connectivity during psychosis and a relationship between reduced putamen–right anterior insula connectivity and hallucinations. Data suggest that altered intrinsic connectivity links striatal and insular pathophysiology in psychosis.

Alterations in the dopaminergic reward system, predominantly the striatum, constitute core characteristics of schizophrenia.

Functional connectivity of the dorsal striatum during reward-related trial-and-error learning was investigated in 17 people with schizophrenia and 18 healthy volunteers and related to striatal grey matter volume and psychopathology.

We used voxel-based morphometry and psychophysiological interaction to examine striatal volume and connectivity.

A reduced functional connectivity between left striatum and temporo-occipital areas, precuneus and insula could be detected in the schizophrenia group. The positive correlation between grey matter volume and functional connectivity of the left striatum yielded significant results in a very similar network. Connectivity of the left striatum was negatively correlated with negative symptoms.

Present results suggest a disruption in striatal functional connectivity that is closely linked to grey matter morphometry of the striatum. Decreased connectivity between the striatum and psychopathologically relevant networks may explain the emergence of negative symptoms.

Schizophrenia is associated with often widespread changes in white matter structure. Most studies have investigated changes in fractional anisotropy, whereas alterations in radial or axial diffusivity have barely been investigated until now.

To investigate radial diffusivity as a potential marker of dysmyelination in direct relation to abnormalities in neural activation.

Neural activation in association with decision-making under uncertainty was investigated in 19 people with schizophrenia and 20 healthy controls and linked to radial diffusivity as measured by diffusion tensor imaging.

Decision-making under uncertainty was associated with a significantly decreased activation in a frontostriatocingulate network in the schizophrenia group. Structurally, they exhibited increased radial diffusivity in temporal white matter that was negatively correlated with activation in parts of the frontostriatocingulate network.

Present data indicate that altered diffusivity within relevant white matter networks may be closely linked to abnormal neural activation in schizophrenia.