Interestingly, LI contains two distinct populations of either highpass or lowpass cells, with relatively few bandpass cells, which may help explain the similarity in the high and low cutoffs observed for this area (Figure 5D). All areas except AM have significantly different

low cutoff values than V1. This effect was toward lower values in all areas except areas LI and PM, which had a higher mean low cutoff than V1 (Figure 5D, one-way ANOVA, F(6,1205) = 9.91, p < 0.0005; post-hoc comparisons p < 0.05, HSD). Visual areas could also be distinguished in terms of SF high cutoffs ( Figure 5D). All extrastriate areas had significantly lower mean high cutoff than V1, with the exception of PM, which had a slightly higher

mean cutoff than V1, but this effect was not found buy ON-01910 to be significant. Comparing across extrastriate areas showed that high cutoff SFs were similar for all higher visual areas, except LM, which had a significantly higher mean high cutoff than area AL ( Figure 5D, one-way ANOVA, F(6,1445) = 27.55, p < 0.0005; post-hoc comparisons p < 0.05, HSD). Tuning bandwidth for SF was sharper in all extrastriate areas compared to V1, except area LI (Figure S5, one-way ANOVA F(6,903) = 15.23, p < 0.0005; post-hoc comparisons p < 0.05, HSD). Area LM had significantly broader SF tuning than extrastriate areas AL, RL, and AM ( Figure S5, p < 0.05, buy INCB024360 HSD). Area AM had the sharpest spatial frequency tuning bandwidth. These results demonstrate that extrastriate visual areas are more Resminostat selective for SF than V1. We calculated the orientation selectivity index (OSI) at the optimal SF for each neuron (Experimental Procedures). A clear separation could be seen between the cumulative distributions of area V1 compared to all other areas, with the distributions of all extrastriate areas shifted toward higher OSI values (Figure 6A). Population distributions in areas PM,

AL, RL, and especially AM stand out as particularly well tuned for orientation relative to the other areas (Figure 6A). All extrastriate areas except area LI had significantly higher mean OSI values than V1 (Figure 6B, one-way ANOVA F(6,1783) = 41.74, p < 0.0005; post-hoc comparisons p < 0.05, HSD). A subset of areas stood out above the rest: AL, RL, and especially area AM had higher mean OSI values than all other areas, except area PM, which was only significantly lower than area AM ( Figure 6B, p < 0.05, HSD). AM showed the highest OSI of any of the areas, with significantly higher tuning than all areas except AL ( Figure 6B, p < 0.05, HSD). These results were also reflected in the proportion of cells that were highly orientation selective (OSI > 0.5, Figure 6C). All extrastriate areas had a larger proportion of highly orientation selective cells than V1, with AL, RL, AM, and PM having the largest proportions of highly selective cells.