Cholinergic projections to the visual thalamus and superior colliculus

The parabrachial region of the brainstem reticular formation projects to th e dorsal lateral geniculate nucleus of the thalamus and to the intermediate gray layer of the superior colliculus. We used the retrograde axonal trans port of two fluorescent labels to demonstrate that individual parabrachial cells project to both structures. The results suggest that cholinergic cell s of the parabrachial region may coordinate the relay of visuosensory infor mation to the cortex with the onset of orienting movements. (C) 1999 Elsevi er Science B.V. All rights reserved.