Speech and Music

[Richard Pastore <pastore@xxxxxxxxxxxxxx>]

Given the broad range of discussion on speech and music, I will throw in
the special session which Barbara Acker and I organized for the 1996
Acoustical Society meeting in Indianapolis.  I have reproduced the abstra=
ct
from the presentation by Isabelle Peretz who, with colleagues, is making
direct neurophysiological comparisons of speech and music for different
types of patients.  I also have reproduced  the abstract from Sandra
Trehub's paper.=20


Music and speech in a neuropsychological perspective. Isabelle Peretz
(Dept. of Psychology, University of Montreal, CP 6128, Centre-ville,
Montreal, Quebec, Canada H3C 3J7)  =20
    Neuropsychology - defined as the study of the relations between brain
organization and mental functioning - has concerned itself from its
earliest days with the processing of speech and music.  The first steps
were taken in the speech domain, via the observation of selective speech
impairments following damage to specific areas of the brain (Broca, in Vo=
n
Bonin, Some Papers on the Cerebral Cortex ; Wernicke, in Brain Function, =
3,
1-16).  These initial findings swiftly prompted the exploration of music
disorders (Bouillaud; Bull. del=92Academie de Medicine, 30, 752-68).  Suc=
h
observations are labeled aphasia and amusia, respectively, and reflect a
long-standing concern to describe the selectivity of the disorders
observed. This issue of specificity is even more prevailing/acute in
contemporary neuropsychology, with the advances made in brain imaging and
in experimental psychology.  Current knowledge will be summarized and
organized along two main questions:  1)  Is music, like speech, subserved
by neural circuitries devoted to its processing? and 2) What are the
boundaries of neuropsychological separability between music and speech?

Perceptual Anchors and Magnets in Infancy.  Sandra E. Trehub (University =
of
Toronto, Erindale Campus, Mississauga, ON, Canada L5L 1C6)  =20
Research on adults' and children's perception of tone sequences or melodi=
es
reveals that they more readily detect the same magnitude of change in the
context of a "good" or well-formed sequence than in the context of a "poo=
r"
or less well-formed sequence.  Because well-formedness is typically
confounded with familiarity, the origin of such performance asymmetries
often remains unclear.  In recent studies, however, 6-month-olds exhibite=
d
adult-like patterns of performance, raising the possibility of processing
predispositions for "good" auditory sequences.  Such sequences could be
considered "natural" prototypes, and would be expected to occur frequentl=
y
across cultures.  Natural prototypes might serve a perceptual anchoring
function for novice and experienced listeners, facilitating the acquisiti=
on
of certain kinds of information.  Kuhl argues, however, that phonetic
prototypes operate differently, being less discriminable from other sound=
s
within the same category than are non-prototypes.  In other words, the
"good" instances function as magnets rather than anchors.  On the one han=
d,
it is useful for "natural" prototypes to function as anchors, being highl=
y
distinctive and memorable.  On the other hand, sufficient flexibility is
necessary for the acquisition of culture-specific or "magnetic" prototype=
s.=20

To Sandra's work, I would add our own work (Acker & Pastore, P&P, 1995,
vol. 57,  863-874) demonstrating a perceptual anchor effect for musical
chords, in contrast to Pat Kuhl's magnet effect for speech.

Dick Pastore