Surround Suppression in Primate V1

Abstract

We investigated the spatial organization of surround suppression in primate primary visual cortex (V1). We utilized drifting stimuli, configured to extend either from within the classical receptive field (CRF) to surrounding visual space, or from surrounding visual space into the CRF or subdivided to generate direction contrast, to make a detailed examination of the strength, spatial organization, direction dependence, mechanisms, and laminar distribution of surround suppression. Most cells (99/105, 94%) through all cortical layers, exhibited suppression (mean reduction 67%) to uniform stimuli exceeding the CRF, and 43% exhibited a more than 70% reduction. Testing with an annulus revealed two different patterns of surround influence. Some cells (37% of cells), classical surround suppression (CSS) cells exhibited responses to an annulus encroaching on the CRF that were less than the plateau in the spatial summation curve. The majority (63%), center-gated surround suppression (CGSS) cells, showed responses to annuli that equaled or exceeded the plateau in the spatial summation curve. Analysis suggested the CSS mechanism was implemented in all cells while the CGSS mechanism was implemented in varying strength across the sample with the extreme reflected in cells that gave larger responses to annuli than to a center stimulus. Reversing the direction of motion of the portion of the stimulus surrounding the CRF revealed four different patterns of effect: no reduction in the degree of suppression (22% of cells), a reduction in surround suppression (41%), a facilitation of the response above the level to the inner stimulus alone (37%), and a facilitation of the response above that to the inner stimulus alone that also exceeded the values associated with an optimal inner stimulus. The facilitatory effects were only seen for reverse direction interfaces between the central and surrounding stimulus at diameters equal to or more than the CRF size. The zones driving the suppressive influences and the direction contrast facilitation were often spatially heterogeneous and for a number of cells bore strong comparison with the class of behavior reported for surround mechanisms in MT. This suggests a potential role, for example, in extracting information about motion contrast in the representation of the three dimensional structure of moving objects.

Surround Suppression of V1 Neurons Mediates Orientation-Based Representation of High-Order Visual Features

“…Several previous studies have examined spatial organization of the CRF and surround by presenting one patch in the CRF and another patch at one of several locations outside the CRF (Cavanaugh et al 2002b;Jones et al 2001;Vinje and Gallant 2000;Walker et al 1999). In these studies, the boundary between the CRF and the surround was typically determined from a size-tuning curve or as a circumference outside which a stimulus was ineffective if presented to the surround alone.…”

Real-time imaging of single nerve cell apoptosis in retinal neurodegeneration

“…Analysis of two macaque monkeys was performed while animals were anesthetized [sufentanil 4 g͞kg per hour or halothane (0.1-0.4%) in 70% N 2 O͞30% O 2 ] and paralyzed (0.1 mg͞kg per hour vecuronium bromide) by using published methods (16). After intravitreal SSP administration (2.5, 5.0, 7.5, and 10 g in 50 l), animals were imaged for at least 6 h.…”

Motion detection, noise reduction, texture suppression, and contour enhancement by spatiotemporal Gabor filters with surround inhibition

“…Furthermore, neurophysiological studies have also showed that, once a cell is activated by a stimulus in its classical receptive field (CRF), another, simultaneously presented stimulus outside that field can have an effect on the cell response (Blakemore and Tobin 1972;Knierim and van Essen 1992;Nothdurft et al 1999;Jones et al 2001). This, mostly inhibitive, effect is known as nonclassical receptive field inhibition or surround suppression.…”

“…A further aim of the current work is to explore some functional aspects of surround suppression in motion processing using a computational model. Surround interactions are observed in different cortical regions such as V1 Jones et al 2001, middle temporal (MT/V5) (Allman et al 1985;Raiguel et al 1995) and lateral medial superior temporal (MST) (Eifuku and Wurtz 1998), which are areas involved in processing motion information. Also, it is known that the RFs of about one half of the cells in MT have antagonistic surrounds (Allman et al 1985;Tanaka et al 1986;Raiguel et al1995;Bradley and Anderson 1998;Born 2000;DeAngelis and Uka 2003;Born and Bradley 2005).…”