Purchase this article with an account.
Adam Kohn; The influence of surround suppression on adaptation effects in primary visual cortex. Journal of Vision 2011;11(11):2. doi: 10.1167/11.11.2.
Download citation file:
© ARVO (1962-2015); The Authors (2016-present)
Adaptation has been used extensively to probe mechanisms of visual processing. Neurophysiological studies have measured how adaptation affects single neurons, using stimuli tailored to evoke robust responses.
Understanding the consequences of adaptation, however, requires measuring effects on neural populations, which include many cells that are weakly driven by the adapter. To provide a more complete view of how adaptation affects neural responses, we implanted microelectrode arrays in primary visual cortex of macaque monkeys and measured orientation tuning and contrast sensitivity before and after prolonged adaptation with a range of stimuli. Whereas previous studies have emphasized that adaptation suppresses responsiveness and repels tuning (termed, stimulus-specific suppression), we find that adaptation can also lead to response facilitation and attractive shifts in V1 tuning. Using a simple computational model, we show that which of these effects occurs depends on the relative drive provided by the adapter to the receptive field and suppressive surround. Our data reveal a richer repertoire of adaptation effects than previously considered and provide a simple explanation for previously disparate findings concerning the effects of adaptation on tuning in V1 and MT. More generally, our results suggest an intimate relationship between spatial and temporal contextual effects, with implications for interpreting fMRI data and for understanding the functional role of rapid sensory-driven plasticity.
This PDF is available to Subscribers Only