Development of spatial frequency selectivity in striate cortex of vision-deprived cats.

Single unit activity was recorded in the striate cortex of vision-deprived cats aged between 3 and 8 weeks. Contrast sensitivity or response measurements made using moving sinusoidal gratings were used to construct spatial frequency tuning curves. At 3 weeks sensitivity, selectivity (assessed both as the narrowness of the tuning curve bandwidth and as the proportion of selective cells), and optimal spatial frequency, are all better than in 2 week old normally reared cats, and comparable with those of 3 week old normally reared cats. After 3 weeks of age no further improvements take place, although distributions of sensitivity, best spatial frequency and bandwidth overlap with those of normal cortical cells, and selectivity is clearly better than in adult LGN cells. These results are consistent with the idea that the spatial properties of cortical cells are at least partly predetermined, but that many cells require visual experience to develop normally.