title: The activation of the cortical hand area by toe tapping in two bilateral upper-extremities amputees with extraordinary foot movement skill.
abstract: Functional reorganization of the human brain after an arm amputation has been documented in several investigations, but as far as we know, there has been no report on amputees with skilled foot movement ability. To further assess the power of functional reorganization of the brain after an amputation, we investigated two bilateral upper-extremities amputees who were professional sculptors and painters with their feet. Performance tests showed that they possessed high foot movement ability. Functional MRI data indicated that toe tapping of the amputees not only activated the classical foot primary motor cortex, but also activated the hand area. In the T1-weighted MRI, the central sulci of both amputees kept their characteristic shape. Our study suggests that there is a remarkable power of neural plasticity in the motor cortex, and the maturation of the cortex develops in response to daily practice. The possible mechanisms of the reorganization are tentatively discussed.
authors.affiliation: Department of Radiology, Sir Run Run Shaw Hospital, Medical College of Zhejiang University, Hangzhou City 310016, Zhejiang Province, China. yuxiaojing@mail.hz.zj.cn
authors.forename: Xiaojing
authors.initials: X
authors.lastname: Yu
authors.forename: Shizheng
authors.initials: S
authors.lastname: Zhang
authors.forename: Hai
authors.initials: H
authors.lastname: Liu
authors.forename: Yizhang
authors.initials: Y
authors.lastname: Chen
mesh_terms: D000328:Adult; D000674:Amputees; D001132:Arm / Q000601:surgery; D005528:Foot / Q000502:physiology*; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008279:Magnetic Resonance Imaging; D008297:Male; D009044:Motor Cortex / Q000502:physiology*; D009068:Movement / Q000502:physiology*; D012984:Software; D014034:Toes / Q000502:physiology