Abstract
There is ample behavioral evidence that different aspects of visual function develop over different time courses. Furthermore, there is evidence that higher form vision – represented by tasks like figure-ground segmentation and contour integration – matures later than acuity and contrast sensitivity. What remains unclear is how different developmental time courses relate to changes in neural representations. Part of the difficulty is due to the absence of a clear and concise map that links different visual functions to specific visual brain areas or neural substrates. We capitalized on recent findings that linked the processing of higher-order statistics of naturalistic texture images to neural responses in area V2 and sought to characterize the behavioral and neural developmental time course of naturalistic texture sensitivity in non-human primates. We constructed synthetic texture patterns with variable amounts of higher-order statistical structure of original natural images. We studied behavioral sensitivity and neuronal selectivity in macaques ranging in age from 26 to 172 wk. We tested five animals, one of which contributed both behavioral and neural data. We measured sensitivity to naturalistic structure using a 2AFC discrimination task. We measured neuronal responses to the same textures with multielectrode "Utah" arrays targeting the foveal representation of V2 in three awake, head free, fixating macaques. Our results show increased behavioral sensitivity to naturalistic statistics from the youngest to the oldest animals. We found texture selective neuronal responses at all ages, but the mean population texture selectivity increased with age. Lower selectivity in the younger animals was associated with weaker neural activity and longer visual and texture-selective response latencies. These results suggest that sensitivity to natural image statistics improves with age, and that this improvement may be associated with changes in visual processing in V2.
Meeting abstract presented at VSS 2017