SPEECH PERCEPTION

Question 1

What are speech signals?

Answer 1

When you can tell when a word has stopped and started again

Question 2

What does the amplitude waveform show us?

Answer 2

How the pressure changes over time

Question 3

What does the spectrogram show?

Answer 3

How energy at various frequencies changes over time.

Question 4

What is a formant?

Answer 4

Resonance of the vocal tract

Question 5

Where are formants located?

Answer 5

At different frequencies for different vowels.

Question 6

How does the ear process sound?

Answer 6

1) Acoustic waveforms enter ear canal and strike the tympanic membrane
2) tympanic membrane sets in motion the ossicles in the middle ear, which transmit mechanical vibrations to the cochlea, where the basilar membrane vibrates.
3) Hair cells on the basilar membrane stimulate nerve fibers in the auditory nerve.

Question 7

What do we know about brain processing for speech perception: Challenge of variability?

Answer 7

• Vowel quality does not correspond to absolute formant values
• The same vowel corresponds to different formant frequencies for different speaker groups.

Question 8

What are some notes made about the vowel perception through formants analysis?

Answer 8

• Many different vowels
• Speaker group not identified
• Overall lap in vowel formants substantial

Question 9

How much info is contained in the sound waves of fluent speech?

Answer 9

Most often we recognize words with fluent speech (not isolated words or symbols).