A temporary loss of reflex activity in the brainstem or spinal cord following destruction of the cerebral cortex. As time passes this state of suppressed reflex activity is replaced by one of unduly exaggerated reflexes and spasticity of the limbs.
In a person with a focal brain injury, a reduction in synaptic activity (and often, cerebral blood flow and metabolism) in a part of the brain that is remote from the injury. Brain functions that are lost as a result of diaschisis often are restored with rehabilitation or the return of blood flow.