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Auditieve waarneming - Speech perception

4 important questions on Auditieve waarneming - Speech perception

What is pure word deafness?

Damage to the left hemisphere. These patients are able to identify environmental sounds and music, but not speech. The patients are able to produce speech, but heard speech appears to be too fast or distorted.

What is a spectogram?

Plots how the frequency of sound changes over time with the intensity of the sound represented by level of darkness.

What is categorical perception?

A way the brain deals with variability in the acoustic input. Refers to the fact that continious changes in input are mapped on to discrete percepts.

Also provides one way of dealing with variabillity in the acoustic signal due to co-articulation: the fact that the production of a phoneme is influenced by the preceding and proceeding phonemes.

What is the nature of stored representations and how does this process occur?

The auditory signal is matched on to motor representations for producing one's own speech rather than matching to an acoustic template. This is the motor theory of speech perception.

This would predict that damage to these motor/mirror regions in humans would result in severe difficulties in speech perseption/production, but this is not the case. Patients with lesions in this area have the mildest of impairmentsi n speech perception. This suggests that auditory-related regions alone can support efficient perception of speech sounds.