Task 9 - Speech perception

Question 1

Acoustic stimulus (or acoustic signal)

Answer 1

Speech sounds are produced by the position or the movement of structures within the vocal apparatus, which produce patterns of pressure changes in the air called the acoustic stimulus, or the acoustic signal – The acoustic signal for most speech sounds is created by air that is pushed up from the lungs past the vocal cords and into the vocal tract

Question 2

Articulators

Answer 2

by moving this the shape of the vocal tract is altered – it includes structures such as the tongue, lips, teeth, jaw, and soft palate

Question 3

Formants

Answer 3

the frequencies at which these peaks occur

Question 4

Sound spectrogram

Answer 4

the formants for the vowel /ae/ are shown in the sound spectrogram – it indicates the pattern of frequencies and intensities over time that make up the acoustic signal

Question 5

Formant transitions

Answer 5

rapid shifts in frequency preceding or following formants – and they are associated with consonants

Question 6

Coarticulation

Answer 6

the overlap between the articulation of neighboring phonemes

Question 7

Perceptual constancy

Answer 7

the fact that we perceive the sound of a phoneme as the same even though the acoustic signal is changes by coarticulation

Question 8

Categorical perception

Answer 8

occurs when stimuli that exist along a continuum are perceived as divided into discrete categories

Question 9

Voice onset time (VOT)

Answer 9

the continuum in categorical perception – the time delay between when a sound begins and when the vocal cords begin vibrating

Question 10

Phonetic boundary

Answer 10

the VOT when the perception changes from /da/ to /ta/ - when one is not sure between which sound one hears

Question 11

Multimodal

Answer 11

our perception of speech can be influenced by information from a number of different senses

Question 12

McGurk effect

Answer 12

it illustrates that although auditory information is the major source of information for speech perception, visual information can also exert a strong influence on what we hear

Question 13

Audiovisual speech perception

Answer 13

the influence of vision on speech perception

Question 14

Phonemic restoration effect

Answer 14

participants listen to a recording of the sentence “The state governors met with their respective legislatures convening in the capital city.” Warren replaced the first /s/ in “legislatures” with the sound of a cough and told his subjects that they should indicate where in the sentence the cough occurred. None of the participants identified the correct position of the cough, and, even more significantly, none noticed that the /s/ in “legislatures” was missing

Question 15

Speech segmentation

Answer 15

the perception of individual words in a conversation - separation of the continuous stream of words

Question 16

Transitional probabilities

Answer 16

the way sounds follow one another in a language – the chance that one sound will follow another sound baby often follows the word pretty - also with letters, like x is not likely to follow x buth h is likely to follow a t (phonemes)

Question 17

Indexical characteristics

Answer 17

characteristics that carry information about speakers such as their age, gender, place of origin, emotional state, and whether they are being sarcastic or serious

Question 18

Aphasia

Answer 18

damage to specific areas of the brain causes language problems

Question 19

Broca’s aphasia

Answer 19

patients with damage to the broca’s area in the frontal lobe – They have labored and stilted speech and can only speak in short sentences. They are, however, capable of comprehending what others are saying (can include it in these pathways but cannot say it only has to do with where – where pathway)

Question 20

Wernicke’s aphasia

Answer 20

patients with damage to the Wernicke’s area in the temporal lobe – They can speak fluently, but what they say is extremely disorganized and not meaningful. These patients have great difficulty understanding what other people are saying. In the most extreme form of Wernicke’s aphasia, the person has a condition called word deafness, in which he or she cannot recognize words, even though the ability to hear pure tones remains intact (what pathway)

Question 21

Voice cells

Answer 21

(recorded from neurons in the monkey’s temporal lobe – part of the what processing stream for hearing) respond more strongly to recordings of monkey calls than to calls of other animals or to “non-voice” sounds - respond only to human voices

Question 22

Dual-stream model of speech perception

Answer 22

has proposed a ventral (or what) pathway starting in the temporal lobe that is responsible for recognizing speech, and a dorsal (or where) pathway starting in the parietal lobe that is responsible for linking the acoustic signal to the movements used to produce speech (an addition to the streams that already exist)

Question 23

Motor theory of speech perception

Answer 23

This theory proposes that (1) hearing a particular speech sound activates motor mechanisms controlling the movement of the articulators, such as the tongue and lips, that are responsible for producing sounds; and (2) activation of these motor mechanisms, in turn, activates additional mechanisms that enable us to perceive the sound. Thus, the motor theory proposes that activity of motor mechanisms is the first step toward perceiving speech