We used fMRI to investigate the effects of tactile co-activation on the topographic organization of the human primary somatosensory cortex (SI). Behavioral consequences of co-activation were studied in a psychophysical task assessing the mislocalization of tactile stimuli. Co-activation was applied to the index, middle and ring fingers of the right hand either synchronously or asynchronously. Cortical representations for synchronously co-activated fingers moved closer together, whereas cortical representations for asynchronously co-activated fingers became segregated. Behaviorally, this pattern coincided with an increased and reduced number of mislocalizations between synchronously and asynchronously co-activated fingers, respectively. Thus, both synchronous and asynchronous coupling of passive tactile stimulation is able to induce short-term cortical reorganization associated with functionally relevant changes.
- somatosensory cortex
- rat barrel cortex
- tactile coactivation
Pilz, K. S., Veit, R., Braun, C., & Godde, B. (2004). Effects of co-activation on cortical organization and discrimination performance. Neuroreport, 15(17), 2669-2672. https://doi.org/10.1097/00001756-200412030-00023