Disconnections in schizophrenia

This article reviews the dysconnection hypothesis of schizophrenia with an account of how dysfunctional integration among neuronal systems might arise, based upon the role of neuronal plasticity in shaping the connections and ensuing dynamics that underlie brain function. The hypothesis is that the pathophysiology of schizophrenia is expressed at the level of modulation of associative changes in synaptic efficacy; specifically plasticity in those brain systems responsible for learning, memory and emotion. This modulation is mediated by ascending neurotransmitter systems that; (i) have been implicated in schizophrenia and (ii) are known to be involved in consolidating synaptic connections during learning. This would translate, in functional terms, into a disruption of the reinforcement of adaptive behaviour that is consistent with the disintegrative aspects of schizophrenic neuropsychology.