PNB 2XB3 Lecture Notes - Lecture 7: Abducens Nerve, Central Sulcus, Epley Maneuver

• School: McMaster University
• Department: Psychology, Neuroscience & Behaviour
• Course: PNB 2XB3
• Professor: Daniel Goldreich

Document Summary

Vestibular system detects rotational acceleration, linear acceleration, and tilt. Ear contains the cochlea, but also contains three mutually perpendicular circular organs (semi-circular canals mutually perpendicular to one another; doesn"t matter which way the cartesian coordinate frame points, just as long as they"re perpendicular to each other) Utricle and saccule detect head tilt and linear acceleration (?: same endolymph in scala media of the cochlea also fills the vestibular labyrinth, receptor cells are hair cells. Receptor hair cells are in the utricle and saccule: axons that they activate are vestibular axons that make up the second component of the 8th cranial nerve (join the auditory nerves that come from the cochlea) Slide 10 second graph depicts number of action potentials: last two graphs shows tilt in opposite direction activity reduces, adaptation is present (reduction in firing rate) Semicircular canal: little bulge on each canal (called the ampulla, hair cell bodies are in the crista, whole canal is filled with endolymph.