Week 6 Flashcards
Why is phase difference less useful for localising high frequency sounds?
There are more possible points where the FREQUENCY? is the same DOUBLE CHECK
Is frequency encoded first in one or two ears
2
What happens when the higher order harmonics of a sounds are present, but the fundamental is missing?
The first harmonic is ‘filled in’, even when separate harmonics are presented to different ears. Therefore higher level structure, be (beyond superior, are involved, due)
What is the human auditory range, in terms of loudness?
0-120 db
describe the 2 basic mechanisms of loudness perception?
1, Overall firing rate: The louder the sound, the more the neuron fires( More neurons fire, and they fire more vigourously. 2.
List some factors that influence loudness perception?
Duration (longer = louder), Frequency (higher = louder (generally! - 3000-5000 hz are perceived to be the loudest) However ,as the overall amplitude goes up, the effect of frequency becomes smaller.
In trying to detect an object location in space using the auditory system, name the 3 aspects of an object you try to determine?
Horizontal direction (not bad), vertical direction(ok with head movement), distance(not good). (Vision more effective!)
Describe the mechanics of auditory space perception?
It’s a binaural mechanism. A) Interaural time delay - 1. onset difference (time delay between the two ears 2. Phase difference (sounds likely to be in different phases when it reaches different ears - less effective with high frequency sounds)
B) Interaural intensity difference - Sound will be less intense in ear that is further away (Sound losing energy, head acting as shadow)
Is the basilar membrane involved with sound localisation?
No!
Interaural time difference is most useful for localising _____ sounds
low frequency
Interaural intensity difference is most useful for detecting ______ sounds
high frequency
Which sound localisation cue is most useful for detecting mid range sounds (1000-3000hz)?
None!!!
How does head movement enhance the sound localisation cues?
Can experience different sound intensity/times by adjusting ear position.
Name a reason why we are more effective at detecting horizontal position compared to vertical?
Wider range of head movements available to us in the horizontal dimension, ears are located in the same horizontal plane.
Name some mechanisms of detecting object distance using auditory perception?
Reverberation - energy ratio of direct and reflected sounds - depends on reflective qualities of objects. Loudness, can only provide relative distance.
