Objective      To research the brain activation modes during motor execution and motor imagery

and explore the neuromechanism of motor imagery.       Methods      Twenty-three healthy right-handed persons were recruited

and the contents of oxyhemoglobin

deoxyhemoglobin and total hemoglobin in the brain during motor execution and motor imagery were measured by functional near infrared reflectance spectroscopy (fNIRS)

and the data were analyzed by statistical test and model estimation.       Results      The activating areas during left-hand motor execution were right-side supplementary motor area(SMA)

premoter cortex(PMC) and primary motor(M1) areas

and the activating area during left-hand motor imagery was right-side PMC area. The activating areas during right-hand motor execution were left-side PMC

M1 and SMA areas

and the activating areas during right-hand motor imagery were left-side PMC and M1 areas. All the activating areas were contralateral cerebral regions.       Conclusion      fNIRS can show the cerebral activation states in the stimulus tasks

and the cerebral cortex activating areas and strength are similar during motor execution and motor imagery.