AWA is a set of two ciliated neurons that are associated with the sheath cells of the amphid sensilla (figure 1). The cell bodies of AWA are situated in the lateral ganglia and send processes into the ventral cord via the amphid commissures. The processes run anteriorly in the ventral cord near the ventral surface of the cord and project into the nerve ring, where they run near the middle of the neuropile. The processes of AWA meet and terminate at the dorsal mid-line with a gap junction. The predominant synaptic output is to AIZ (a); there are also some synapses to AFD (b), AIY (c) and ASE usually in dyadic combination with AIZ. A few of the synaptic vesicles are dark cored (a). There are gap junctions to AIA (d). Magnifications: (a, d) x 25500, (b, c) x 12750.
Web adaptation, Thomas Boulin, for Wormatlas, 2001, 2002