2008 Hearing, Music, Language and the brain

2008 Hearing, Music, Language and the brain - The human...

Info iconThis preview shows pages 1–7. Sign up to view the full content.

View Full Document Right Arrow Icon
The human ear: sound waves to vibration of basilar membrane
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Sound transduction • Sound causes air to vibrate • This needs to be converted into fluid vibration- requires a transducer • This is caused by vibration of the tympanic membrane which causes the malleus and incus (levers) to push the stapes (piston) in and out of the oval window. This causes a pressure difference across the cochlea causing the basilar membrane to vibrate. • Vibration of the basilar membrane of the cochlea causes deflection of hair cells which initiates action potentials in nerve fibers of the auditory nerve: mechanical energy is transduced to electrical energy.
Background image of page 2
The origin of the tonotopic map
Background image of page 3

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Tonotopic map • Excursion of different portions of the basilar membrane of the cochlea occurs in response to different frequencies of sound • Proximal portion of cochlea responds to high frequencies; distal portion, to low frequencies. • In humans the frequency range is about 20 Hz to 20 KHz. • This map is preserved up to the auditory cortex. • Equivalent to somatotopic map for touch- pressure and retinotopic map for vision.
Background image of page 4
Auditory pathways: bilateral organization • Auditory nerve (8 th cranial nerve) projects to cochlear nucleus. • Cochlear nucleus projects to superior olivary nucleus: processes timing and intensity information from both ears Æ binaural sound localization. • Lateral lemniscus fiber pathway (not labeled) carries impulses to inferior colliculus Æ medial geniculate Æ auditory cortex
Background image of page 5

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Auditory cortex • Columnar organization similar to other primary cortex
Background image of page 6
Image of page 7
This is the end of the preview. Sign up to access the rest of the document.

Page1 / 19

2008 Hearing, Music, Language and the brain - The human...

This preview shows document pages 1 - 7. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online