The topographic organization of signals sent from frontal eye field to superior colliculus

graphic organization of signals sent from the frontal eye field to the superior colliculus. J. Neurophysiol. 83: 1979–2001, 2000. The fron-tal eye field (FEF) and superior colliculus (SC) contribute to saccadic eye movement generation, and much of the FEF’s oculomotor influ-ence may be mediated through the SC. The present study examined the composition and topographic organization of signals flowing from FEF to SC by recording from FEF neurons that were antidromically activated from rostral or caudal SC. The first and most general result was that, in a sample of 88 corticotectal neurons, the types of signals relayed from FEF to SC were highly diverse, reflecting the general population of signals within FEF rather than any specific subset of signals. Second, many neurons projecting from FEF to SC carried signals thought to reflect cognitive operations, namely tonic dis-charges during the delay period of a delayed-saccade task (delay signals), elevated discharges during the gap period of a gap task (ga