TY - JOUR
T1 - Somatosensory dynamic gamma-band synchrony
T2 - A neural code of sensorimotor dexterity
AU - Tecchio, Franca
AU - Graziadio, Sara
AU - Barbati, Giulia
AU - Sigismondi, Roberto
AU - Zappasodi, Filippo
AU - Porcaro, Camillo
AU - Valente, Giancarlo
AU - Balsi, Marco
AU - Rossini, Paolo Maria
PY - 2007/3
Y1 - 2007/3
N2 - To investigate neural coding characteristics in the human primary somatosensory cortex, two fingers with different levels of functional skill were studied. Their dexterity was scored by the Fingertip writing test. Each finger was separately provided by a passive simple sensory stimulation and the responsiveness of each finger cortical representation was studied by a novel source extraction method applied to magnetoencephalographic signals recorded in a 14 healthy right handed subject cohort. In the two hemispheres, neural oscillatory activity synchronization was analysed in the three characteristic alpha, beta and gamma frequency bands by two dynamic measures, one isolating the phase locking between neural network components, the other reflecting the total number of synchronous recruited neurons. In the dominant hemisphere, the gamma band phase locking was higher for the thumb than for the little finger and it correlated with the contra-lateral finger dexterity. Neither in the dominant nor in the non-dominant hemisphere, any effect was observed in the alpha and beta bands. In the gamma band, the amplitude showed similar tendency to the phase locking, without reaching statistical significance. These findings suggest the dynamic gamma band phase locking as a code for finger dexterity, in addition to the magnification of somatotopic central maps.
AB - To investigate neural coding characteristics in the human primary somatosensory cortex, two fingers with different levels of functional skill were studied. Their dexterity was scored by the Fingertip writing test. Each finger was separately provided by a passive simple sensory stimulation and the responsiveness of each finger cortical representation was studied by a novel source extraction method applied to magnetoencephalographic signals recorded in a 14 healthy right handed subject cohort. In the two hemispheres, neural oscillatory activity synchronization was analysed in the three characteristic alpha, beta and gamma frequency bands by two dynamic measures, one isolating the phase locking between neural network components, the other reflecting the total number of synchronous recruited neurons. In the dominant hemisphere, the gamma band phase locking was higher for the thumb than for the little finger and it correlated with the contra-lateral finger dexterity. Neither in the dominant nor in the non-dominant hemisphere, any effect was observed in the alpha and beta bands. In the gamma band, the amplitude showed similar tendency to the phase locking, without reaching statistical significance. These findings suggest the dynamic gamma band phase locking as a code for finger dexterity, in addition to the magnification of somatotopic central maps.
UR - http://www.scopus.com/inward/record.url?scp=33846958397&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=33846958397&partnerID=8YFLogxK
U2 - 10.1016/j.neuroimage.2006.12.002
DO - 10.1016/j.neuroimage.2006.12.002
M3 - Article
C2 - 17234434
AN - SCOPUS:33846958397
VL - 35
SP - 185
EP - 193
JO - NeuroImage
JF - NeuroImage
SN - 1053-8119
IS - 1
ER -