Delayed maturation of temporal Frequency-tuning functions in macaque V2
Society of Neuroscience Annual Meeting
Society of Neuroscience
Washington, DC / November 12-16, 2005
Publication Date / Copyright Date
Previously, we reported that the maturation of receptive-field center/surround mechanisms of V2 neurons is delayed relative to that of V1 (Zhang et al, 2005). However, little is known about the normal development of the temporal response properties of V1 or V2 neurons. In this study we compared the maturation of temporal frequency tuning functions of individual V1 and V2 neurons in macaque monkeys. At 2-, 4- and 8-weeks of age, microelectrode recording experiments were conducted in anesthetized and paralyzed infant monkeys. After optimizing stimulus orientation, size, and spatial frequency for each unit, we measured the neuron's responsiveness as a function of stimulus temporal frequencies. To our surprise, the mean temporal resolution of V1 neurons for 2- or 4-week old infants, determined by locating the unit’s characteristic temporal frequency (Movshon et al, 2002), was not significantly different from that of adults. However, the mean characteristic temporal frequency of V2 neurons for all infant ages was significantly lower than that of adults and the mean temporal resolution was inversely correlated with their information density (see our poster on response reliability in V1 and V2 of infant monkeys, Zhang et al, 2005). Also the present results add new evidence for the hypothesis that the functional maturation of the primate visual brain proceeds in a hierachical manner (Distler et al, 1996; Movshon and Kiorpes, 2003; Zhang et al, 2005).
Nakatsuka, C.; Zhang, Bin; Zheng, Jianghe; Bi, Hua; Lin, Y.; Watanabe, Ichiro; Smith, Earl L. III; and Chino, Yuzo M., "Delayed maturation of temporal Frequency-tuning functions in macaque V2" (2005). College of Optometry Faculty Proceedings, Presentations, Posters, Speeches, Lectures, etc.. 55.