Neurons in the temporal cortex changed their preferred direction of motion dependent on shape

To investigate neuronal mechanisms that integrate different visual modalities such as motion and shape, neuronal activities in the superior temporal polysensory area (STP) were recorded from monkeys that were watching rotating images. In total, 194 neurons were identified as visually responsive. Of these, 73 neurons (38%) showed differential response depending on both shape and direction of motion (MS neurons). Of these 73 neurons, 21 (29%) were identified as reversal type MS neurons (MSr neurons), that is, they responded to an opposite preferred direction when the shape was different. The results confirm that neurons in the STP can be simultaneously activated by different attributes of visual stimuli. The data also suggest that individual STP neurons can process more than one type of visual stimulus.