P-NE008. Association between excitability of the spinal motor neuron function and an evaluation index for image recall ability

Abstract

Introduction. We examined the association between the image recall ability and excitability of the spinal motor neuron function during motor imagery of the Box and Block Test (BBT). Methods. 14 right-handed healthy subjects participated in this study. The image recall ability was evaluated by the Vividness of Movement Imagery Questionnaire (VMIQ) and Mental Chronometry (MC) using the BBT. We investigated the spinal motor neuron function during motor imagery of the BBT. The motor imagery task was performed with the right index finger and thumb at the fastest possible speed in the BBT. Subjects were then asked to perform the BBT at the same speed in motor imagery. We evaluated the correspondence between the number of blocks moved with motor imagery and the actual physical movement. The excitability of the spinal motor neuron function was examined using the F-wave. We measured the F-wave of the right thenar muscles after stimulating the right median nerve at the wrist. The F-wave was recorded at rest and during motor imagery of BBT. This study examined the correlation between the VMIQ and MC. In the statistical analysis, the Wilcoxon signed-rank test was used to compare the F/M amplitude ratio at rest and during motor imagery of the BBT. Significance was set below the 5% level. Results. The VMIQ and MC results were similar for the image recall ability. The F/M amplitude ratio significantly increased during motor imagery of the BBT compared to that at rest in the subjects with a low image recall ability. The BBT showed no significant difference in the F/M amplitude ratio compared to that at rest in subjects with a high image recall ability. Conclusion. The VMIQ and MC have a correlation and may be useful for evaluating image recall ability.