OBJECTIVE:

To investigate the effect of repetitive transcranial magnetic stimulation (rTMS) on picture naming.

BACKGROUND:

Previous studies have shown that rTMS disrupts ongoing speech processes when delivered over frontal or parietal areas of the dominant hemisphere.

METHODS:

In 15 healthy right-handed male individuals, rTMS trains of 20 Hz with a duration of 2 seconds and an intensity of 55% of maximum stimulator output were delivered either to Wernicke's area, to the right-hemisphere homologue of Wernicke's area, to Broca's area, or to the primary visual cortex. Twenty black-and-white line drawings, which the individuals had to name as quickly as possible, were shown immediately after the completion of rTMS and again 2 minutes later.

RESULTS:

Immediately after the end of a train over Wernicke's area a shortening of naming latency was observed compared with naming without rTMS (p < 0.001). No significant effects on picture naming were observed 2 minutes later or at any time after stimulation of the right-hemisphere homologues of Wernicke's area, Broca's area, or the visual cortex.

CONCLUSION:

Repetitive transcranial magnetic stimulation over Wernicke's area leads to a brief facilitation of picture naming by shortening linguistic processing time.