ABSTRACT
Morphological predictions are not completely certain, because of uncertainty of assumptions and relative numbers of neurones in each hemisphere, and the length of axoplasm contributed by axons of each calibre. The central hypothesis that the two hemispheres have different repertoires of axonal conduction delays leads to a number of specific predictions about electrographic activity and evoked potentials. The most important axons in such a comparison are the unmyelinated ones principally, are the ones with delays longer than 10 msec. The simplest prediction from the above hypothesis is that the cortico-cortical connections in white matter of the left hemisphere would include a higher proportion of fine calibre or unmyelinated axons than in the white matter of the right hemisphere. The cortico-cortical axons are likely to form a larger volume fraction of the cerebral white matter than the cell bodies and dendritic and local axonal arborizations of such axons will form for the cortical grey matter.
