Auditory pathway

n Inner and outer hair cells – connect to auditory nerve

q Efferent pathway

q Afferent pathway

n Cochlear nucleus – brainstem, see lateral inhib, enhance freq resolution

n Superior olivary nucleus – brainstem, partial crossover of information (excit in 1 ear, inhib in other

q Medial – low freq, lateral – high freq

n Inferior colliculus – midbrain, auditory spatial info, also goes to superior coll.

q Tonotopic – w/in layers, sim freq near each other

n Medial Geniculate nucleus – thalamus

n Primary auditory receiving area – A1, deep in grove in temporal lobe, tonotopic map

q Low freq – left, high freq – right

q Columnar arrangement – same char freq

q Localization of sound (interaural time diff detectors)

n Nonprimary auditory cortex

q Resp to changes from high to low

q Complex tones (many freq)

q Panoramic neurons – signal timing of neural firing, used for sound localization

q Neurons that resp to sound near head