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Left/right brain integration

Diana Diamond ddiamond at shell01.ozemail.com.au
Wed Dec 4 08:05:29 EST 1996

Ian Walker (iw103 at york.ac.uk) wrote:
: Whilst we're discussing this I thought I'd share with you all a 
: fascinating study I read recently which found that the corpus callosum 
: (the main bundle of connections between the two hemispheres) was thicker 
: and better-connected in musicians than in controls, but only if they had 
: started learning their instrument before the age of 7.  Interesting, eh?

: Ian

A gross map of biases from a draft paper of mine...

"The Structure of Personality is not, therefore, a strictly geometric form
but more an emergent flexible form. In the emergent sense, the hemispheres
of the neocortex take-on the characteristics of each other but in
differing levels of refinement: 

LH bias                      (raw state)             RH bias
fine serial comms      <----------------------> fine non-serial comms
gross non-serial comms <----------------------> gross serial comms
gross context (single) <----------------------> fine context (multi)
fine relational        <----------------------> gross relational
gross hierarchic       <----------------------> fine hierarchic
fine parts handling    <----------------------> gross parts handling
gross wholes           <----------------------> fine wholes (continuum)

(this allows for the occasional 'blunders' where the overall functionality
of hemispheres seems reversed - left-handedness etc. The serial/non-serial
dichotomy seems to be fairly fundamental thus allowing for LH control of
handedness etc and the LH processing of visual, but serial biased,
language eg ASL. But under extreme conditions one hemisphere could take-on
the work of the other if allowed to during the early developmental years.
The only way that this could happen is if the 'raw' infant brain was
integrated and 'unfolded' in a specific manner due to environmental

infants, when presented with a specific-sense stimulus will respond *as a 
whole*, they turn their whole being to the stimulus. Environmental 
pressure causes sensory differentition which we then try to re-integrate. 
(education differentiates and then tries to re-integrate).

Most of the gross cerebral wiring is done by 10 (even with a degree of 
culling) and thus the importance of a rich developmental environment.

In music, those taught music at an early age will learn it 
'wholistically' and develop a sense of 'feel', for it is emotion that 
ties the parts of the whole. Those taught music as a language (reading) 
will often develop left-hemisphere biases. 'good' musicians use both 
(oscillate). The distinction is parts vs wholes.

The fine/gross audition/vision skills seem to be the 'roots' of the
possible biases, with audition having a sequential bias and vision a
non-sequential bias. It is documented, for example, that the RH auditory
area has a bias to dealing with sounds considered to be 'wholes' rather
than parts of a serial communication. Intent has an affect on mental
activity. If you assume data to be serial communication then an LH bias
emerges, if not, an RH bias emerges in dealing with the information. This
suggests that LH stroke victims who have less degrees of lateralization or
who have learnt serial language in a rote manner (as 'wholes') may have
better serial language recovery skills than the 'average' individual.)"

Chris Lofting c/o ddiamond at ozemail.com.au
PS drafts available (email me):

"The sense of dichotomy" parts 1 and 2 (dichotomy as an abstract sense)

"A Model of Neocortical behaviour" (brain structure bias)

"The Logic of the Esoteric" (about the 'value' of esoteric maps)

All of the above lean to my 'sense of dichotomy' concept which deals with 
the maps we make and the 'fact' that they are metaphors for whole, parts, 
aspects distinction using dichotomy.

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