Reduction of Continuous Theta Burst Stimulation-Induced Motor Plasticity in Healthy Elderly With COMT Val158Met Polymorphism

• Published in: Annals of rehabilitation medicine Vol. 38; no. 5; pp. 658 - 664
• Main Authors: Lee, Nam Jae, Ahn, Hyun Jung, Jung, Kwang-Ik, Ohn, Suk Hoon, Hong, Jeonghoon, Kim, Yun Joong, Yoo, Woo-Kyoung
• Format: Journal Article
• Language: English
• Published: Korea (South) Korean Academy of Rehabilitation Medicine 01.10.2014; 대한재활의학회
• Subjects: Original; 재활의학; Transcranial Magnetic Stimulation; Catechol-O-methyltransferase; Neuronal plasticity; Motor cortex; Genetic polymorphism
• ISSN: 2234-0645; 2234-0653
• DOI: 10.5535/arm.2014.38.5.658

To delineate whether cortical plasticity induced by continuous theta burst stimulation (cTBS) differed according to catechol-O-methyltransferase (COMT) gene polymorphism in healthy older adults. Eighteen healthy older volunteers (mean age 73.78±5.04; 12 females and 6 males) were recruited. Volunteers randomly assigned in either a sham-first or real cTBS first group participated in two separate TMS visits with at least a 2-day wash-out period. Genotyping was carried out at baseline by a separate researcher who was blinded. cTBS was delivered in a hot spot over M1 at an active motor threshold of 80%. Motor evoked potentials (MEPs) were obtained at 120% of the resting motor threshold before and after sham/cTBS. The relative MEP to baseline was significantly decreased 0 and 10 minutes post-stimulation and increased 40 minutes post-stimulation, as compared with the sham condition. Immediately after cTBS, the Val/Val group had a significantly reduced relative MEP value, as compared with the MET carrier group. In healthy older persons, cTBS-induced motor plasticity was reduced in the COMT Val/Val group as compared with the (158)Met carrier group.