Responses of MT and MST neurons to one and two moving objects in the receptive field

Recanzone, G. H., R. H. Wurtz, and U. Schwarz. Responses of the receptive field of a neuron by using either grating stimuli MT and MST neurons to one and two moving objects in the re- (Movshon et al. 1985; Rodman and Albright 1989) or ran-ceptive field. J. Neurophysiol. 78: 2904–2915, 1997. To test the dom dot patterns (Qian and Andersen 1994; Snowden et al. effects of complex visual motion stimuli on the responses of single 1991, 1992) and have shown that the introduction of a sec-neurons in the middle temporal visual area (MT) and the medial ond stimulus can affect the response of most cells in MT. superior temporal area (MST) of the macaque monkey, we com- Qian and Andersen (1994) suggest that MT neurons sup-pared the response elicited by one object in motion through the press the inputs from local regions within the receptive fieldreceptive field with the response of two simultaneously presented of the neuron that contain stimuli moving in opposite direc-objects moving in different directions through the receptive field. tions and Movshon et al. (1985) and Rodman and AlbrightThere was an increased response to a stimulus moving in a direction other than the best direction when it was paired with a stimulus (1989) have suggested that MT is the first cortical area moving in the best direction. This increase was significant for all in which different directions of motion of the individual directions of motion of the non-best stimulus and the magnitude components of a complex stimulus are combined to form a of the difference increased as the difference in the directions of representation of the global motion of the stimulus. the two stimuli increased. Similarly, there was a decreased response In addition to processing information related to the percep-to a stimulus moving in a non-null direction when it was paire