Interações ao redor do campo receptivo central medeiam a codificação de contraste espacial dependente do contexto na retina

quinta-feira, novembro 08, 2018

Receptive field center-surround interactions mediate context-dependent spatial contrast encoding in the retina

Maxwell H Turner, Gregory W Schwartz, Fred Rieke

University of Washington, United States; Northwestern University, United States



Antagonistic receptive field surrounds are a near-universal property of early sensory processing. A key assumption in many models for retinal ganglion cell encoding is that receptive field surrounds are added only to the fully formed center signal. But anatomical and functional observations indicate that surrounds are added before the summation of signals across receptive field subunits that creates the center. Here, we show that this receptive field architecture has an important consequence for spatial contrast encoding in the macaque monkey retina: the surround can control sensitivity to fine spatial structure by changing the way the center integrates visual information over space. The impact of the surround is particularly prominent when center and surround signals are correlated, as they are in natural stimuli. This effect of the surround differs substantially from classic center-surround models and raises the possibility that the surround plays unappreciated roles in shaping ganglion cell sensitivity to natural inputs.