The Journal of Neuroscience, September 23, 2009, 29(38):12009-12019; doi:10.1523/JNEUROSCI.2118-09.2009
Previous Article | Next Article 
Behavioral/Systems/Cognitive
Large-Scale Expansion of the Face Representation in Somatosensory Areas of the Lateral Sulcus after Spinal Cord Injuries in Monkeys
Shashank Tandon,
Niranjan Kambi,
Leslee Lazar,
Hisham Mohammed, and
Neeraj Jain
National Brain Research Centre, Manesar 122050, India
Correspondence should be addressed to Neeraj Jain, National Brain Research Centre, N.H. 8, Manesar 122050, India. Email: neeraj.jain{at}nbrc.ac.in or Email: njain.nbrc{at}gmail.com
Transection of dorsal columns of the spinal cord in adult monkeys results in large-scale expansion of the face inputs into the deafferented hand region in the primary somatosensory cortex (area 3b) and the ventroposterior nucleus of thalamus. Here, we determined whether the upstream cortical areas, secondary somatosensory (S2) and parietal ventral (PV) areas, also undergo reorganization after lesions of the dorsal columns. Areas S2, PV, and 3b were mapped after long-term unilateral lesions of the dorsal columns at cervical levels in adult macaque monkeys. In areas S2 and PV, we found neurons responding to touch on the face in regions in which responses to touch on the hand and other body parts are normally seen. In the reorganized parts of S2 and PV, inputs from the chin as well as other parts of the face were observed, whereas in area 3b only the chin inputs expand into the deafferented regions. The results show that deafferentations lead to a more widespread brain reorganization than previously known. The data also show that reorganization in areas S2 and PV shares a common substrate with area 3b, but there are specific features that emerge in S2 and PV.
Received April 30, 2009;
revised Aug. 11, 2009;
accepted Aug. 16, 2009.
Correspondence should be addressed to Neeraj Jain, National Brain Research Centre, N.H. 8, Manesar 122050, India. Email: neeraj.jain{at}nbrc.ac.in or Email: njain.nbrc{at}gmail.com