Cerebrally lateralized mental representations of hand shape and movement

摘要: Previous psychophysical and neuroimaging studies suggest that perceiving the handedness of a visually presented hand depends on sensorimotor processes are specific to limb stimulus may be controlled by cerebral hemisphere contralateral limb. Therefore, it was hypothesized disconnection between hemispheres would disrupt mental simulation ipsilateral, but not contralateral, hemisphere. This hypothesis examined present study in which two callosotomy patients eight healthy controls judged drawings left right hands various positions, without moving or inspecting their own hands. Stimuli were for 150 msec visual hemifield. As predicted, each hemisphere, patients’ accuracy high when above chance ipsilateral Controls’ both conditions. Response time analyses indicate patients, like controls, mentally simulated reaching into postures. When laterality imagined posture did detect mismatch, guessing with response bias responding basis shape similarity. We conclude could represent movement hand. Mentally simulating one’s action discriminating body part depend lateralized somatosensory representations.