The auditory pit, also known as the otic pit, is the first rudiment of the
internal ear. It appears shortly after that of the eye, in the form of a patch of thickened
ectoderm
The ectoderm is one of the three primary germ layers formed in early embryonic development. It is the outermost layer, and is superficial to the mesoderm (the middle layer) and endoderm (the innermost layer). It emerges and originates from the o ...
, the
auditory plate, over the region of the
hind-brain. The auditory plate becomes depressed and converted into the auditory pit (or otic pit
).
References
Embryology of nervous system
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