Instrumentation is in place to capture images for morphometry of neurons developing in the absence of electrical activity. Redesign of multicompartment chambers for the study of activity effects on synapse stabilization / elimination improves optical resolution and axonal growth. Antibodies against the vesicular acetylcholine transporter label a subpopulation of neurons and synaptic terminals, and may allow the immunohistochemical identification of cholinergic neurons as early as one week after plating. Antibodies against the homeobox gene (Hoxa7) product label neuronal and not glial nuclei.