The EEG and Cocaine Sensitization: A Hypothesis

The author presents the hypothesis that reduced delta EEG power observed in cocaine withdrawal is related to changes in dopamine (DA) transmission related to cocaine sensitization. Evidence for this hypothesis includes the topographic anatomical correspondence between the putative site of delta generation and the cortical terminal field of the mesotelencephalic DA system, as well as the laminar distribution and ultrastructural features of DA terminals in frontal cortex that appear to be adapted to the modulation of the delta rhythm, a global forebrain EEG mode. The effect of DA on membrane conductances of individual pyramidal neurons also suggests that DA exerts a significant influence on delta power by modulating the transition between global and local EEG modes. Access to a neural correlate of sensitization via noninvasive EEG methodology could be useful in investigating the relationship of stimulant sensitization to the clinical syndrome of cocaine dependence.