Somatosensory cortex of the neonatal pig: II. Topographic organization of the secondary somatosensory cortex (SII)

Abstract

Multiunit microelectrode recording techniques were used to delineate the somatotopic organization of the secondary somatosensory cortex (SII) of the neonatal pig. Barbiturate anesthetized piglets ranging in age from 7 days preterm to 2 months postpartum were used. The SII area, located lateral to the rostral and middle suprasylvian sulci, was found to contain a complete somatotopic representation of the contralateral body surface with a significant proportion of bilateral input for all body regions except the forehoof and forelimb. The SII forelimb and hindlimb representations were found to possess a "striplike" orientation in a rostral to caudal sequence, and the trunk representation was located posterolateral to the hindlimb representation, giving SII an inverted appearance. Two apparently separate face representations were delineated; one posterolateral to the projection from the trunk and the other anterior to the forehoof region. Unlike SI, which possesses a disproportionately large representation of the rostrum, SII has no specialized representation of the rostrum. The overall organization of SII supports the contention that this cortical region provides a more generalized representation of the entire body surface than does SI.

Organization of somatosensory cortex and distribution of corticospinal neurons in the eastern mole (Scalopus aquaticus)

“…The identity of the possibly incomplete second representation is less certain, but it appears to correspond to the second somatosensory area S2, in that S2 has a parallel mirror image face representation along the caudolateral border of S1 in other mammals (Sur et al, 1981;Calford et al, 1985;Krubitzer et al, 1986Krubitzer et al, , 1995Krubitzer and Kaas, 1990;Craner and Ray, 1991). Alternatively, the second representation could be the parietal ventral area, PV, which has been identified in cortex just rostral to S2 in a range of species (Krubitzer et al, 1986(Krubitzer et al, , 1993Krubitzer and Kaas, 1990;Krubitzer and Calford, 1992).…”

The use of pigs in neuroscience: Modeling brain disorders

“…The sulcal and gyral anatomy the pig brain has been described in detail in a number of studies (Craner and Ray, 1991b;Dellman and McClure, 1975;Jarvinen et al, 1998;Jelsing et al, 2006b;Kruska, 1970;Okada et al, 1999). The extent and pattern of the cortical convolution pattern is comparable to that of other ungulates, e.g.…”

Effective Connectivity Maps in the Swine Somatosensory Cortex Estimated from Electrocorticography and Validated with Intracortical Local Field Potential Measurements

“…It receives input from the snout bilaterally (Craner and Ray, 1991a). The SII cortex is located in the sulcal and gyral walls of the suprasylvian cortex lateral to the coronal gyrus (Craner and Ray, 1991b). This area receives bilateral projections from the snout.…”