Efferent Connections of Brainstem Neurons

Abstract

In this chapter we describe both immunohistochemically identified and nonidentified brainstem neuronal aggregates and their projections within and outside the brainstem core. We dissociate cholinergic from monoaminergic systems not only because of their chemical distinctness but also because of their dissimilar projection patterns to rostral brain structures. Whereas the ascending projections arising in brainstem cholinergic neurons are overwhelmingly relayed in the thalamus, monoaminergic neurons project much less densely to thalamic nuclei but have direct access to cortical neurons.