Auditory system development: primary auditory neurons and their targets.
The neurons of the cochlear ganglion transmit acoustic information between the inner ear and the brain. These placodally derived neurons must produce a topographically precise pattern of connections in both the inner ear and the brain. In this review, we consider the current state of knowledge concerning the development of these neurons, their peripheral and central connections, and their influences on peripheral and central target cells. Relatively little is known about the cellular and molecular regulation of migration or the establishment of precise topographic connection to the hair cells or cochlear nucleus (CN) neurons. Studies of mice with neurotrophin deletions are beginning to yield increasing understanding of variations in ganglion cell survival and resulting innervation patterns, however. Finally, existing evidence suggests that while ganglion cells have little influence on the differentiation of their hair cell targets, quite the opposite is true in the brain. Ganglion cell innervation and synaptic activity are essential for normal development of neurons in the cochlear nucleus.
Rubel
Edwin W
EW
Virginia Merrill Bloedel Hearing Research Center, Department of Otolaryngology/Head and Neck Surgery, University of Washington, Seattle 98195-7923, USA. rubel@u.washington.edu
Fritzsch
Bernd
B
D000818:Animals; D001306:Auditory Pathways / Q000166:cytology / Q000196:embryology* / Q000378:metabolism; D002450:Cell Communication / Q000502:physiology; D002454:Cell Differentiation / Q000502:physiology; D002465:Cell Movement / Q000502:physiology; D017626:Cochlear Nucleus / Q000166:cytology / Q000196:embryology* / Q000378:metabolism; D018507:Gene Expression Regulation, Developmental / Q000502:physiology; D006198:Hair Cells, Auditory / Q000166:cytology / Q000196:embryology* / Q000378:metabolism; D006801:Humans; D009414:Nerve Growth Factors / Q000172:deficiency / Q000235:genetics; D009475:Neurons, Afferent / Q000166:cytology / Q000378:metabolism*; D013136:Spiral Ganglion / Q000166:cytology / Q000196:embryology* / Q000378:metabolism
D009414:Nerve Growth Factors