NEUROPLASTICITY AND PSYCHIATRY

Objective: There is increasing concern that the course of psychiatric disorders may be affected by parameters such as the duration and inten sity of symptoms of initial episodes of illness. As this indicates tha t abnormal function produces long-term changes within the brain, a rev iew of the neuroscience literature regarding neuroplasticity is warran ted. Method: This article is a selective review, focusing in particula r on results obtained from physiological experiments assessing plastic ity within the mammalian neocortex. The possible relevance of results to psychiatry is discussed. Results: While the most dramatic examples of neuroplasticity occur during a critical period of neural developmen t, neuroplasticity can also occur in adult neocortex. Neuroplasticity appears to be activity-dependent: synaptic pathways that are intensive ly used may become strengthened, and conversely, there may be depressi on of transmission in infrequently used pathways. Conclusions: Results from neurophysiological experiments fend support to the clinical obse rvation that the intensity and duration of a psychiatric disorder may adversely alter its long-term course. Rapid aggressive treatment may p revent this from occurring. While pharmacotherapy may reduce the durat ion and severity of symptoms, it may also have an independent, as yet unknown, effect on neuroplasticity.