The generation of horizontal off-center saccades.

Horizontal saccades are initiated in the lab by a display of nine LEDs spaced five degrees apart and centered with respect to primary position (looking straight ahead). From this setup, there are seventy two combinations of unique saccades. Temporal and spatial information from these recorded saccades are compared to saccades generated from a hypothetical model using the same experiment paradigm. The model uses two neural integrator feedback loops within the premotor circuitry. One is to control the duration of the high frequency burst of neural activity that caused the muscles to contract at saccade velocities and the other to produce the proper neural signal necessary to keep the eye in its new post-saccade position. Depending on the initial position of the eye, different temporal and spatial schemes are necessary to produce the same size saccade. These control strategies are realized by modifying known neural signals within the premotor circuitry.