Dr M. C. Siff
07-12-1995, 01:13 AM
Recently I sent out information on various e-mailings, concerning
Balance and Motor Control, as well as on an innovative system of
seated rehabilitation. In hypothesising about the success of
plyometric activities in seated fitness, I mentioned work done on the
possible connection between neural development and ballistic
processes. Several users wanted more information on this topic.

THis information now follows:

Neurophysiologist Dr W Calvin proposed the interesting hypothesis
that the brains' planning of ballistic movements may have played a
major role in the development of language, music and intelligence
over the ages (Scientific American, Oct 1994).

He made this proposal since ballistic movements and
language processes involve some of the same regions of the brain, in
particular those associated with sequencing and planning. In
reaching this conclusion, he emphasises that ballistic movements,
unlike slower cocontractive movements (e.g. see Basmajian "Muscles
Alive") require a great deal of planning and problem solving. The
difference is linked to the neural processes underlying feedforward
as opposed to feedback control systems.

Calvin adds that improvement in language skills might improve
dexterity and vice versa, an idea which we are using to analyse why
the Ericson seated fitness system seems to have played a role in
facilitating recovery of some speech function in brain damaged
subjects - this system characteristically makes use of carefully
choreographed ballistic movements that are quite unlike the
cocontractive slower arm ergometry and toning classes offered to the
disabled. If Calvin's hypotheses are even partially proved, then far
greater numbers of functionally illiterate American footballers and
basketballers may be induced into improving their language abilities
in order to perform better! The converse of more academic students
practising demanding rapid motor skills may also gain some ground for
improving their cognitive ability!

Something I am also examining is the difference between purely
automatic plyometric activities and other explosive movements that
involve cognitive processes. This has entailed understanding
the differences between respondent and operant conditioning by
various training strategies. Insufficient emphasis may well
have been placed on researching and training the central nervous
processes that are implicated in rapid, ballistic and plyometric
movements. It would be interesting to hear if anyone else is working
in this area.

Dr Mel C Siff
School of Mech Eng
University of Witwatersrand
South Africa

************************************************** ********************