Figure 6.
The middle temporal area (MT) of marmoset. (A) Photomicrograph of adjacent coronal sections, showing the histological distinctiveness of area MT revealed by myelin (left) and Nissl (right) stains. MT stands out as heavily myelinated in comparison with most cortical areas. Although the boundaries are less obvious, MT can also be identified in Nissl stained sections by the thinner and denser layer IV, and by the thicker layer VI, in comparison with adjacent areas. Scale bar = 1 mm. (B) Direction tuning for gratings and plaids in two representative directions elective MT neurons. The left panel illustrates the responses of a “component-cell,” which shows bi-lobed tuning for plaids, as if it responded to the individual gratings that comprise the plaid. The right panel shows the responses of a “pattern-cell,” which has similar direction tuning to gratings and plaids. (C) Spatial frequency tuning of a representative “component cell” in the peripheral representation of MT; the response to low spatial frequencies is neglible. (D) Tuning for the size of a patch of drifting grating, of optimal spatial frequency, showing large receptive field size of neurons in area MT. Scale bars in B show 20 impulses/s. (B–D) adapted from Solomon et al. (2011).