Subject: tone deafness From: at <hermesNATLAB.RESEARCH.PHILIPS.COM> Date: Wed, 6 Dec 1995 12:24:59 +0100
As to the question of ``tone deafness'' for music, I also know of ``tone deafness'' in speech. I know some people who are perfectly able to indicate in a spoken utterance which syllable has an pitch-accent, but they are unable to say whether that accent is lent by a rise (a rising pitch movement), a fall (a falling pitch movement), or by a rise-fall (a rapid succession of a rising and a falling pitch movement). All three types of accent-lending pitch movements occur very regularly in languages like Dutch, German, and both British and American English. Furthermore, the intonation in the speech spoken by those ``tone deaf'' people is perfect. One of those people had worked for years at IPO within the Hearing-and-Speech Group, and knew much about intonation. Another observation is that many people are unable to reproduce an utterance spoken by someone with the same intonation contour. For example, though in about 70% of all cases questions end on a high level tone, many questions end on a low tone, especially wh-questions. For some studies, I wanted to have some utterances with well specified pitch contours, among which there were some wh-questions which I wanted to end on a low tone. Many subjects are unable to do this task; when I speak both those sentences, one time ending on a low tone, the other time lending on a high tone, some subjects react with ``But I don't hear the difference!'', let alone that they can reproduce it. A study by Tahta and Wood (1981), (``Age changes in the ability to replicate foreign pronunciation and intonation'', Language and Speech 24(4), 363-372), shows that children in the age from 8 to 11 learn much faster to reproduce ``foreign'' intonation patterns than 11 to 14 year old children. Their study related to native English-speaking children who were imitating French and Armenian intonation patterns. Furthermore, being ``musical'' or having a fine ear for music, is not a sufficient condition for being able to reproduce an intonation pattern without much effort. Those musically trained people who doubt this, are challenged to reproduce the intonation patterns of some simple utterances spoken by speakers of an East-Asian tone language with five, six or seven lexical tones. Before addressing what this all implicates, I want to mention that speech and music are different in many ways (although there are transitions). One of the differences is that (most) music has a tonal centre, which determines a limited set of correct pitches, whereas running speech, as used in every-day communication, has not. A probably related finding is that I found evidence that speech intonation in perceived on an ERB-rate scale (JASA, 90, 97-102), while, there is no doubt about that, music is perceived on a logarithmic frequency scale. If this is true, but it is sometimes questioned, this means that one of the criteria for good intonation in music, viz. being ``in tune'', does not apply to speech. Producing a correct intonation in speech is independent of any correct tuning. This shows that the perceptual mechanism which decides the correctness of the intonation in a piece of music, is different from the (language-specific) perceptual mechanism which decides whether the intonation contour of a spoken utterance is correct. >From the discussion in AUDITORY and from above, it appears that the perceptual mechanisms underlying the perception of intonation in speech and music are quite different. In (most) music, in contrast with speech, a tonal centre determines a limited set of correct pitches. In this sense music is special, not speech. Furthermore, all native speakers of the language mostly produce ``correct'' intonation patterns. In speech, native speakers after the age of about 11 can mostly determine whether an utterance is ``correct'' or whether there is something wrong; being aware of what is wrong is something different. My conclusion is that the question of ``tone deafness'' in music should be kept separated from what happens in ``non-sung'' speech. To make things even more complicated, I fear there is a third perceptual mechanism related to frequency discrimination, and that is our sensitivity to formant freqencies. We can easily follow frequency variations of 40 octaves/s, e.g. the second formant in ``we''. Any such change in the periodicity of a signal will not be perceived as a change in pitch, but will induce the perception of a new ``note'', a click, or whatever. I think, also this perceptual mechanism should be kept separated from the previous two. -- Dik J. Hermes Institute for Perception Research / IPO P.O. Box 513 NL 5300 MB Eindhoven *!*!*!*!*!*!*!*!*!*!*!*!*!*!*!*!*!*!*!*!*!*!*!*!*!*!*!*!*!* ! ! * NB After 10 October 1995 telephone number, * ! telefax number and E-mail address will change: ! * * ! Tel.: +31 40 2773842 / +31 40 2773873 ! * Fax.: +31 40 2773876 * ! E-mail: hermes(at)natlab.research.philips.com ! * * !*!*!*!*!*!*!*!*!*!*!*!*!*!*!*!*!*!*!*!*!*!*!*!*!*!*!*!*!*!