Subtle abnormalities in frontal white matter have been reported in bipolar disorder.

To assess whether impaired integrity of white matter tracts is associated with bipolar disorder and genetic liability for the disorder.

A total of 19 patients with psychotic bipolar I disorder from multiply affected families, 21 unaffected first-degree relatives and 18 comparison individuals (controls) underwent diffusion tensor imaging. Whole brain voxel-based analyses compared fractional anisotropy between patients and relatives with controls, and its relationship with a quantitative measure of genetic liability.

Patients had decreased fractional anisotropy compared with controls in the genu of the corpus callosum, right inferior longitudinal fasciculus and left superior longitudinal fasciculus. Increased genetic liability for bipolar disorder was associated with reduced fractional anisotropy across distributed regions of white matter in patients and their unaffected relatives.

Disturbed structural integrity within key intra- and interhemispheric tracts characterises both bipolar disorder and genetic liability for this illness.

People with prodromal symptoms have a very high risk of developing psychosis.

To use functional magnetic resonance imaging to examine the neurocognitive basis of this vulnerability.

Cross-sectional comparison of regional activation in individuals with an ‘at-risk mental state’ (at-risk group: n=17), patients with first-episode schizophreniform psychosis (psychosis group: n=10) and healthy volunteers (controls: n=15) during an overt verbal fluency task and an N-back working memory task.

A similar pattern of between-group differences in activation was evident across both tasks. Activation in the at-risk group was intermediate relative to that in controls and the psychosis group in the inferior frontal and anterior cingulate cortex during the verbal fluency task and in the inferior frontal, dorsolateral prefrontal and parietal cortex during the N-back task.

The at-risk mental state is associated with abnormalities of regional brain function that are qualitatively similar to, but less severe than, those in patients who have recently presented with psychosis.

Depersonalisation disorder is characterised by emotion suppression, but the cerebral mechanisms of this symptom are not yet fully understood.

To compare brain activation and autonomic responses of individuals with the disorder and healthy controls.

Happy and sad emotion expressions in increasing intensities (neutral to intense) were presented in an implicit event-related functional magnetic resonance imaging (fMRI) design with simultaneous measurement of autonomic responses.

Participants with depersonalisation disorder showed fMRI signal decreases, whereas the control group showed signal increases in response to emotion intensity increases in both happy and sad expressions. The analysis of evoked haemodynamic responses from regions exhibiting functional connectivity between central and autonomic nervous systems indicated that in depersonalisation disorder initial modulations of haemodynamic response occurred significantly earlier (2s post-stimulus) than in the control group (4–6s post-stimulus).

The results suggest that fMRI signal decreases are possible correlates of emotion suppression in depersonalisation disorder.

Grey matter and other structural brain abnormalities are consistently reported in first-onset schizophrenia, but less is known about the extent of neuroanatomical changes in first-onset affective psychosis

To determine which brain abnormalities are specific to (a) schizophrenia and (b) affective psychosis

We obtained dual-echo (proton density/T2-weighted) magnetic resonance images and carried out voxel-based analysis on the images of 73 patients with first-episode psychosis (schizophrenia n=44, affective psychosis n=29) and 58 healthy controls

Both patients with schizophrenia and patients with affective psychosis had enlarged lateral and third ventricle volumes. Regional cortical grey matter reductions (including bilateral anterior cingulate gyrus, left insula and left fusiform gyrus) were evident in affective psychosis but not in schizophrenia, although patients with schizophrenia displayed decreased hippocampal grey matter and increased striatal grey matter at a more liberal statistical threshold

Both schizophrenia and affective psychosis are associated with volumetric abnormalities at the onset of frank psychosis, with some of these evident in common brain areas

First-episode psychosis is typically preceded by a prodrome in which there is deterioration in global and social functioning

To examine whether the duration of the prodromal phase influences grey and white matter volumes at the onset of psychosis

Eighty-two people were scanned using magnetic resonance imaging when they developed a first episode of psychosis. The duration of the prodromal phase was estimated from detailed interviews and medical records. Voxel-based morphometry was used to assess neuroanatomical abnormalities

A long prodromal phase was associated with smaller grey matter volumes in the cingulate, frontal and left insular cortex, and with less white matter volume bilaterally in the superior longitudinal and uncinate fasciculi and the cingulum

The severity of volumetric abnormalities in first-episode psychosis was greater in those with a long prodrome

It is unclear whether schizophrenia and psychotic bipolar disorder are associated with similar deviations of brain morphometry.

To assess volumetric abnormalities of grey and white matter throughout the entire brain in individuals with schizophrenia or with bipolar disorder compared with the same control group.

Brain scans were obtained by magnetic resonance imaging from 25 people with schizophrenia, 37 with bipolar disorder who had experienced psychotic symptoms and 52 healthy volunteers. Regional deviation in grey and white matter volume was assessed using computational morphometry.

Individuals with schizophrenia had distributed grey matter deficit predominantly involving the fronto-temporal neocortex, medial temporal lobe, insula, thalamus and cerebellum, whereas those with bipolar disorder had no significant regions of grey matter abnormality. Both groups had anatomically overlapping white matter deficits in regions normally occupied by major longitudinal and interhemispheric tracts.

Schizophrenia and psychotic bipolar disorder are associated with distinct grey matter deficits but anatomically coincident white matter abnormalities.

Third rather than lateral ventriculomegaly may be a more specific finding in psychosis. The relevance of ventricular abnormality remains unclear.

To investigate the developmental correlates of ventricular enlargement.

Information on childhood development and magnetic resonance images in 1.5-mm contiguous sections were collected on 21 patients experiencing a first episode of psychosis.

Patients (n=21) had significantly less whole brain volume and enlarged third and lateral ventricles compared to controls (n=25). Third ventricle (r=0.48, P < 0.03) and lateral ventricle (r=0.65, P < 0.01) volumes correlated with developmental score. Patients with developmental delay had significantly larger third and lateral ventricles than those without.

Enlargement of both third and lateral ventricles is found in first-episode psychosis and is related to developmental delay in childhood. Insult to periventricular areas is relevant to the neurobiology of the disease. These findings support the view that schizophrenia involves disturbance of neurodevelopmental processes in some patients.