EFFECTS OF ALCOHOL ON CORTICAL EXCITABILITY AND CONNECTIVITY STUDIED BY COMBINED TRANSCRANIAL MAGNETIC STIMULATION AND ELECTROENCEPHALOGRAPHY

Abstract
Cortical excitability can be studied directly by combining transcranial magnetic stimulation (TMS) with brain imaging methods such as electroencephalography (EEG). Motor and non-motor areas can be stimulated and subsequent brain activity can be measured. Ethanol has been shown to modulate EEG responses evoked by motor-cortex TMS, the effects being largest at the right prefrontal cortex, indicating that ethanol changes the functional connectivity. Furthermore, alcohol decreases the amplitude of EEG responses after left prefrontal stimulation mainly in anterior parts of the cortex, which may be associated with the decrease of the prefrontal cortical excitability. Taken together, TMS combined with EEG provides a new insight to the actions of CNS drugs at the cortical level.

Key words
Alcohol, cortex, EEG, neuroimaging, transcranial magnetic, stimulation

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