Severe schizophrenics as a group show subtle abnormalities of cerebral structure. Cerebral ventricular enlargement is the best replicated finding, and this tends to be associated with impairment of neuropsychological performance. The idea that these abnormalities have a neurodevelopmental origin gains indirect support from the, admittedly less consistent, evidence of abnormalities of cerebral asymmetry and of neuronal migration in adult schizophrenics, as well as from the behavioural, psychomotor, and cognitive impairments reported in preschizophrenic children. However, the relationship between childhood and adult neuropsychological and brain structural findings has not been proven, and we do not know whether only some schizophrenics have a developmental origin, or whether patients differ only in the degree of developmental impairment that they show.

This article describes the use of non-invasive magnetic resonance (MR) methods for the characterization and monitoring of the pathophysiology of experimental brain injury in laboratory animals as a function of time and treatment. The impact of MR in brain research is primarily due to its non-invasive nature, thereby enabling repeated measurements in long-term studies, and due to the type of information that it provides. MR imaging (MRI) enables the measurement of the morphology/anatomy as well as the functional status of tissues under in vivo conditions. Compared to other in vivo imaging modalities, MRI has a high spatial resolution and allows for a remarkable soft tissue differentiation. MR spectroscopy (MRS) provides information on the biochemical/metabolic status of tissues. MR methods which have proven valuable in animal studies, can be readily translated to the clinical situation where MR-based diagnosis and treatment planning play a rapidly increasing role.

After a short introduction into the principles of MR, we will illustrate the remarkable versatility of MR in research on brain injury from recent animal studies. Examples will be mainly drawn from experiments on early injury in focal cerebral ischemia and from research on mechanical brain trauma and excitotoxic lesions. The article ends with a brief description of the perspectives of MR in neuropsychiatry.