Topographic organization of cortical input to striate cortex in the Cebus monkey: A fluorescent tracer study

Abstract

Cortical afferents to area V1 were studied in seven Cebus monkeys by means of retrograde fluorescent tracers. Injections were placed in V1, under electrophysiological guidance, in the regions of representation of both the upper and lower visual quadrants, at eccentricities that ranged from 0.5 to 64 degrees. In all cases retrogradely filled neurons were found in retinotopically corresponding portions of areas V2 and MT, as defined electrophysiologically (Rosa et al: J. Comp. Neurol. 275:326, 1988; Fiorani et al: J Comp Neurol 287:98, 1989). The results also revealed two other visual zones located anterior to V2 here named third and fourth visual areas. A topographical organization of the connections was observed in these areas, with upper quadrant located ventrally and lower quadrant located dorsally. A clear central-peripheral gradient, from the lateral to the medial cortical surface, was also observed in these areas. Lower field injections revealed crude topographic organization in area DZ and a diffuse projecting zone in the annectent gyrus. Peripheral injections in V1 revealed a clear upper and lower field segregation in areas PO and prostriata as well as a complex topography in MST. In addition, another region of labeling revealed the presence of an area, the temporal ventral posterior region, with an organized topographic representation of the upper field, with a central to peripheral gradient, from the lateral to the medial cortical surface. Three groups of cortical areas were distinguished according to the laminar distribution of neurons labeled from V1. In the first group, which is characterized by dense infra- and supragranular labeling, only V2 was included. The second group consists of areas V3, MT, and PO. These areas show dense labeling in the infragranular layers and occasionally sparse labeling in the supragranular layers. Finally, V4 and the other projecting areas, which are characterized by exclusive labeling of the infragranular layers were included in the third group.

The case for a dorsal V3 in the ‘third-tier’ of primate visual cortex: a reply to ‘the case for a dorsomedial area in the primate ‘third-tier’ visual cortex’

“…The view presented in the Rosa et al's commentary is based on retinotopic maps from Rosa's group and connection patterns from Angelucci's group, with all of the work being conducted in marmoset monkeys. As we presented in the original review not only does a large body of anatomical and mapping data in several species other than marmoset support the Lyon & Connolly interpretation of a V3d [2][3][4][5][6][7][8][9][10][11][12][13][14][15], the original work that led Jon Kaas and me to the re-interpretation of a V3d in place of DM was with marmosets as well [16].…”

Cortical Connections of Area V6Av in the Macaque: A Visual-Input Node to the Eye/Hand Coordination System

“…MST shares with V6Av a strong sensitivity to the direction of motion of objects in the visual field (Desimone and Ungerleider, 1986;Saito et al, 1986;Galletti et al, 1996) and has been shown to send a reciprocal projection to the region likely to encompass V6Av in the New World monkey Cebus apella (Rosa et al, 1993). In addition, MST receives specific projections from the regions of V1 and V2 subserving peripheral vision (Sousa et al, 1991;Palmer and Rosa, 2006). A small number of labeled cells were also found in area MT.…”

Projection from Visual Areas V2 and Prostriata to Caudal Auditory Cortex in the Monkey

“…For example, peripheral but not central representations of areas V1 and V2 are connected with numerous dorsal visual stream areas in temporal and parietal cortex (Colby et al 1988;Gattass et al 1990;Nakamura et al 1993;Gattass et al 1997;Ungerleider et al 2008). Area prostriata is reported to have visual function (Sousa et al 1991;Rosa et al 1997) and appears to preferentially connect with the peripheral representation of areas V1, V2, and MT (Palmer and Rosa 2006). Its projections to peripheral MT suggest an involvement in motion processing in visual periphery.…”