Attentional and neurophysiologic effects of repetitive transcranial magnetic stimulation

Twenty-seven healthy subjects were randomly assigned to 1 of 2 equal groups : (1) experimental group (active stimulation) and (2) control group (sham stimulation). A total of 10 Hz repetitive transcranial magnetic stimulation was delivered to the left dorsolateral prefrontal cortex at 80% of the resting motor threshold. The reaction time of the correct response, omission error, and commission error of the auditory and visual continuous performance test scores were measured. The motor evoked potentials, resting motor threshold, short-interval intracortical inhibition, and intracortical facilitation was recorded in the right first dorsal interosseous muscle to determine motor cortex excitability. The reaction time and commission error of the auditory continuous performance test were reduced significantly after 10 Hz repetitive transcranial magnetic stimulation (P < 0.05). Resting motor threshold and short-interval intracortical inhibition was significantly decreased after active repetitive transcranial magnetic stimulation (P < 0.05), with no changes in the latency and amplitude of the motor evoked potentials and intracortical facilitation. In conclusion, high-frequency repetitive transcranial magnetic stimulation to the left dorsolateral prefrontal cortex is shown to improve the attentional function and may be simultaneously associated with changes in neurophysiological activity.