Assignment 2Assignment 2This assignment should be handed in on Thursday September 25th, either in hard copy or by email. If the department photocopier continues to not function, and I am unable to get the readings to you by the end of the week, then the due date for this assignment will be put back.
Reading: Werker (1995), Jusczyk (1997: chapters 3-4)
Students registered for CGSC496 should answer questions 1 and 2 only; students registered for CGSC696 should answer all questions.
1. Based on the chapter by Janet Werker ("Exploring developmental changes in cross-language speech perception"), what are the main changes in speech perception abilities in the first year of life. Werker is reluctant to view these changes as the 'loss' of abilities-why?
2. Lasky et al. (1975: see p.54 of Jusczyk chapter "Early research on speech perception") have shown that 46 month old Guatemalan infants are able to discriminate /d/ from /t/, but that they show a perceptual boundary typical of adult English speakers (e.g. 30ms voice onset time) rather than of adult Spanish speakers (e.g. 15ms voice onset time [this exact figure may be wrong])! We may reasonably assume, however, that these children grew up to perceive the difference between /d/ and /t/ with the same boundary as other Spanish speakers.
Consider the tests that Werker uses to support the claim that adults retain the abilities they had as infants (mention what they are). Could these be used to test Guatemalan adults, to see whether they retain a residue of their infant perceptual abilities? If so, what result(s) would you predict?
3. Werker assumes that there are effectively different 'modes' of perception which mature speakers may use in perceiving speech (i.e. acoustic, phonetic, phonemic). She suggests that toddlers' and adults' apparent loss of abilities is due to reliance on the 'phonemic mode' of perception.
However, based on reading Jusczyk (pp.5665), notice that a number of properties of speech perception may be explainable in terms of general auditory processing abilities, presumably properties of the 'acoustic mode' of perception.
How might we try to reconcile these two sets of findings? Is there in fact any conflict between them? [E.g. do adults have to shift between phonemic and acoustic modes of perception all the time in perceiving speech; should we assume that many properties of the 'acoustic mode' are also specified in the 'phonemic mode'; but wouldn't this be rather redundant?]
Note: this is a rather open-ended question. Your answer does not need to reach firm conclusions, but it does need to make clear what the relevant considerations are.