Visual motion integration by neurons in the middle temporal area of a New World monkey, the marmoset

Non‐technical summary  The machinery of motion vision is highly conserved across New World and Old World monkeys, according to our study of the marmoset visual cortex. The marmoset is a New World primate, part of a lineage that diverged from Old World monkeys some 30–40 million years ago. A small part of the cerebral cortex, area MT, can be identified anatomically in both New and Old World primates. In the macaque, an Old World primate, this area is thought to be important in analysing the motion of complex patterns. Here we quantified the capacity of neurons in area MT of marmosets to extract motion from complex patterns. We find the responses of neurons in area MT of marmosets to be indistinguishable from those in macaques, suggesting that the functional role of this small area of the visual cortex is highly conserved over evolution.