MLUw and MLUm

[Marilyn Vihman]

following up on Ann's comments, I can't resist adding in a reference to a
1982 paper of mine, in Applied Psycholinguistics, 3, which looks at my
son's development along Ann's line [A], even though he was learning a
highly inflected language, Estonian, as well as being exposed to english to
a lesser extent. Courtney Cazden had noted these two approaches in the dev.
of Eve vs. Sarah, among Brown's 3 subjects, in 1972.

- marilyn vihman


> I agree that, especially in early morphosyntactic production there are
>two things going on, and they probably need to be assessed differently.
>On the one hand there is [A] the stringing together of content words/ideas
>(MLUw?); on the other is [B] the increasing inclusion of grammatical
>markers (MLUm?).
>   The trouble with English is that so many of the grammatical markers
>are free morphemes that one is tempted to think that counting *words*
>is the way to go.  However, these capacities probably develop separately,
>showing up as individual differences in early combination.  In fact, the
>kids who go the [B] route are probably the "frame and slot" kids who
>structure their early combinations around morphosyntactic frames.
>I think one sees these patterns even more clearly when one looks at
>languages (like Italian) with more bound morphology.
>   I have found it useful to compute MLU in two ways:
>1) just open-class lexical items (excluding free grammatical morphemes),
>and 2) all morphemes, whether bound or free.
>I believe these measures would equate better across languages than the
>traditional MLUw that grew out of working with English.
>I have tried to address some of these issues in my chapter in Slobin's vol.5:
>A.M. Peters, 1997. "Language typology, prosody and the acquisition of
>grammatical morphemes". In The Crosslinguistic Study of Language
>Acquisition, vol.5, D.I. Slobin, ed. Hillsdale NJ: Lawrence Erlbaum
>Associates, 136-197.
>Ann Peters


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  Marilyn M. Vihman
  Professor, Developmental Psychology  |      /\
  School of Psychology                 |     /  \/\
  University of Wales, Bangor,         |  /\/    \ \
  Gwynedd LL57 2DG, U.K.               | /  ======\=\
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  FAX             382 599              |  B A N G O R

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