Fig. 2

In ferrets and primates, direction selectivity develops postnatally. In ferrets, it has been shown that the development of direction selectivity requires visual experience. a Profile of development of orientation selectivity and direction selectivity in ferrets [19] and rough equivalent in macaque from [29]. b The influence of experience on the development of direction selectivity in ferret. Light-reared animals (that is, typically-reared animals) exhibit strong direction selectivity for animals P63 or older [19]. By contrast, dark-reared animals P63 or older exhibit poor selectivity for direction selectivity. Animals that were dark-reared until P45–50 and then reared under typical conditions (“Early dark-reared”) also failed to develop direction selectivity, indicating that early visual experience is required for the proper development of direction selectivity [19]. Animals that were dark-reared only until P35, and then allowed 2–3 weeks of visual experience, exhibited strong direction selectivity [19]. Finally, artificial experience with moving stimuli for 3–6 h is sufficient to cause a rapid increase in direction selectivity in visually naïve ferrets [35]. Adapted from [19]