Facilitation of picture naming after repetitive transcranial magnetic stimulation

Objective: To investigate the effect of repetitive transcranial magnetic st imulation (rTMS) on picture naming. Background: Previous studies have shown that; rTMS disrupts ongoing speech processes when delivered over frontal o r parietal areas of the dominant hemisphere. Methods: In 15 healthy right-h anded male individuals, rTMS trains of 20 Hz with a duration of 2 seconds a nd an intensity of 55% of maximum stimulator output were delivered either t o 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 s hown immediately after the completion of rTMS and again 2 minutes later. Re sults: Immediately after the end of a train over Wernicke's area a shorteni ng of naming latency was observed compared with naming without rTMS (p < 0. 001). No significant effects on picture naming were observed 2 minutes late r or at any time after stimulation of the right-hemisphere homologues of We rnicke's area, Broca's area, or the visual cortex. Conclusion: Repetitive t ranscranial magnetic stimulation over Wernicke's area leads to a brief faci litation of picture naming by shortening linguistic processing time.