Chapter 10 Flashcards
Physical properties of sound
Frequency
Amplitude
Psychological properties of sound
Pitch
Loudness
Timbre
Pitch
Psychological property of sound
Perception of high & low notes
Loudness
Psychological property of sound
Perceived intensity of sound
Timbre
Psychological property of sound
Perceptual quality of sound
Outer Ear
Amplifies certain frequencies, important for locating sounds
Pinna (pinnae): ear lobes
Auditory canal
Middle Ear
3 tiny bones transfer the mechanical pressure on the eardrum to the oval window
Parts of the middle ear
Malleus (Hammer)
Incus (Anvil)
Stapes (Stirrup)
Inner ear
Converts vibrations into neural impulses
Cochlea
-Basilar membrane
Basilar membrane
A membrane found within the cochlea that contains tiny hair cells linked to receptors
Sound induces mechanical movement of the basilar membrane and the hair cells on it
These movements induce electrochemical changes in the receptor cells, which stimulate associated auditory nerve fibers
Auditory pathway
4-5 synapses from ear to cortex
Medial geniculate nucleus (of the thalamus) projects to the primary auditory cortex
Tonotopic organization
Cortex is tonotopically organized
Some neurons/regions are relatively specialized for coding content
“What” pathway
Temporal lobe
“Where” pathway
Parietal lobe
Locating sounds
Mechanism 1
Inter aural difference
Time differences
-sound arrives at each ear at a different time
Intensity differences
- sound waves decay with distance
- less intense in ear that is further from source
Locating sounds
Mechanism 2
Distortions by head and outer ear
-the shape of the ears distorts incoming sounds in predictable ways that depend on the location of the sound. The brain contains an internal model of how the sounds get distorted
