The Auditory Centers of the Avian Brain

The auditory centers of the avian brain include a flat sheet of neuronal cells (Nucleus laminaris, NL) that indicate sound direction. The upper side of these neurons receive signals from one ear and the lower side receive signals from the opposite ear. What are you seeing? The red area shows the SV2 protein in synapses that indicates neurons that are mature and functional, such as the NL, surrounded by two thick layers of labeled dendrites.  The green area is the 200 kD neurofilament protein labels nerve fibers in the dorsal crossing tract, which carries sound inputs from the opposite ear to the lower dendritic field of NL, and nerves innervating upper dendritic field with inputs from the same side ear.  Finally, focus on the blue areas to see DNA labeled in the cell nuclei.

VIRGINIA MERRILL BLOEDEL HEARING RESEARCH CENTER

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