When neuroimaging was first applied in psychiatric research, it was hoped that it would improve our understanding of the basis of mental health disorders, and thereby lead to improvements in clinical care.

One early approach that proved fruitful was to use imaging to investigate the mechanisms underlying specific psychiatric symptoms, such as auditory hallucinations, though disorder and obsessions. These studies provided new data on the pathophysiology of these psychiatric phenomena, and informed the development of new forms of treatment for these symptoms.

Neuroimaging has also delivered new data on the processes that drive the onset of psychiatric disorders. Its application in the early stages of psychosis has shown that alterations in the structure, function and chemistry of the brain predate the onset of frank illness. Brain scanning may thus be used to predict the likelihood that a young person who is at risk will progress to developing a psychotic disorder. Moreover, understanding the neurobiology of illness onset provides a rational basis for the development of preventive clinical interventions.
Psychosis is usually treated with antipsychotic medications, but these drugs do not work in about a third of individuals. Neuroimaging data suggest that this may be because in some patients, psychosis results from dopamine dysfunction, but in others it is related to disruption in other transmitter systems. Neuroimaging assessments could thus allow clinicians to predict whether a patient is likely to benefit from standard treatment or form an alternative that acts on non-dopaminergic targets.

One promising example of an alternative treatment is Cannabidiol (CBD), which acts on the endocannabinoid system. it is currently being evaluated as a new class of psychiatric treatment.