Response vs. temporal frequency of drifting sinusoidal gratings for V1 complex direction selective cells | ||||
WYETH BAIR and J. ANTHONY MOVSHON | ||||
Center for Neural Science New York University 4 Washington Place, Room 809 New York, NY 10003 Support: Howard Hughes Medical Institute |
ANIMAL | Macaca fascicularis |
PREP | anesthetized (sufentanil), paralyzed (vecuronium) |
DATA TYPE | extracellular spike times |
CELL TYPE | complex, direction selective |
N | 45 cells |
Stimulus
The stimulus was a drifting sinusoidal grating at 100% contrast presented in a circular aperture that covered a region larger than the classical center and surround of each cell. Spatial frequency was fixed at the optimal value. Temporal frequency (TF) was varied from trial to trial from 0.2 to 25 Hz in octave steps. For trials with the parameter ampl set to zero, no stimulus appeared and the response represents the spontaneous firing to a mean gray field. During data collection, the non-dominant eye was occluded with a black, non-reflective surface.
The units of temporal frequency, tf, are 10.24 times cycles/sec, e.g. tf 128 is 12.5 Hz. The variable cycles specifies the number of cycles that the grating drifted on each trial, and is typically related to tf.
Electrophysiological Methods
Bair W, Movshon JA (2004) Adaptive Temporal Integration of Motion\\ in Direction Selective Neurons in Macaque Visual Cortex. J Neurosci 24:7305--7323.
Published analyses of these responses
None.