Effects of repetitive transcranial magnetic stimulation on cognitive function in patients with lesions in prefronal cortex

Abstract

Objective To investigate the effects of repetitive transcranial magnetic stimulation (rTMS) on cognitive function and safety in patients with lesions in prefrontal cortex (PFC). Methods Twenty-one patients with lesions in PFC hospitalized in the Department of Neurosurgery and Department of Neurology, Anqing Hospital Affiliated to Anhui Medical University between January 2012 and October 2014 were enrolled and given regular drug treatment as a background. Event-related potential (ERP) P300 latency and amplitude, Montreal Cognitive Assessment (MoCA) scores were recorded and compared before and after 4-week rTMS treatment. Results Compared with those before rTMS treatment, P300 latency ((367.38±9.79) ms vs (345.43±11.31) ms; t=5.33, P<0.05) was significantly shortened, while amplitude ((4.79±1.02) μV vs (7.84±1.40) μV; t=-8.08, P<0.05), MoCA scores (19.57±2.06 vs 23.91±1.30; t=-8.14, P<0.05), memory test scores (2.19±0.81 vs 4.10±0.89; t=-7.24, P<0.05) and executive function test scores (2.52±1.08 vs 3.57±0.93; t=-3.38, P<0.05) were obviously increased. MoCA scores (18.22±1.56 vs 20.58±1.83; t=-3.11, P<0.05), memory test scores (1.89±0.78 vs 2.42±0.79; t=-2.26, P<0.05) and executive function test scores (1.56±0.53 vs 3.25±0.75; t=-5.76, P<0.05) showed statistically significant difference before rTMS treatment in patients with lesions in either right or left front lobe. Conclusions rTMS which is thought to be a safe procedure can improve cognitive function in patients with lesions in prefrontal cortex. Key words: Transcranial magnetic stimulation; Prefrontal cortex; Cognition; Executive function; Brain damage, chronic