โ Scribed by J. Trimble; G. Phillips
No coin nor oath required. For personal study only.
Using time-domain correlation techniques, the first-and second-order Wiener kernels have been calculated for the system mediating the human visual evoked response. The first-order kernels indicate the linear element is a resonant one, with a natural frequency near 20 Hz, and a memory of approximately 250ms. The transport delay associated with this element is approximately 56ms. The second-order kernels indicate a quadratic nonlinear element with a memory less than 20ms. The analytic form of this element can be approximated by a parabola shifted to the right of the origin. A close correspondance between the spectrum of the first-order kernel and the spectrum of the main diagonal of the second-order kernel suggests the nonlinear element preceeds the linear one. Tests of reproducibility on the first-order kernel and the main diagonal of the second-order kernel suggest they are reliable describing functions for the system mediating the human visual evoked response.
๐ SIMILAR VOLUMES
Visual evoked responses to sinusoidal movement before and after adaptation to linear movement were compared. Fourier analysis indicated that the responses evoked by sinusoidal movement were insensitive to direction of movement. Following adaptation, the harmonics describing the waveforms changed in
set of target movement; hedge=height of the edge above fly; Xstar t =distance from corner of triangle to start position of edge (0 or 50 mm); xescape=distance from corner of triangle to the position of the edge when the fly escapes; xce.ter=distance from corner of triangle to point above the center