Experimentation is planned to find auditory stimuli that would best show a clear
difference from normal subjects. For example, children and adults with autism often
appear to have hyperacusis, which might be due to loss of inhibitory neurons, but on the
other hand might involve increased activity of excitatory neurons. Thus the need could
arise to look for alternative ways of testing auditory processing.
It is expected that fMRI responses in the inferior colliculi will differ from normal in cases of
head injury with visible lesions in the inferior colliculi. Activity changes with different stimuli
in victims of head trauma may then suggest tests most useful in detecting changes that
might result from non-visible impairments of the inferior colliculi.
It is anticipated that alteration in activity in the inferior colliculi will be found in people with
presbyacusis, especially in people who can no longer follow a conversation in a noisy
environment. It is anticipated that activity changes will be seen with fMRI in adults and
children with fetal alcohol syndrome, corresponding to known difficulty with word
recognition in noise (WRIN) tests .
It is anticipated that altered fMRI activity will be found in people with life-long autism,
childhood language delay, and language disorders persisting from childhood. It is
expected that (as in other investigations) decreased activity in the cortical language areas
will be found for subjects with autism [34-36]; see figure 8. Decreased activity and
right-left differences in autistic subjects are currently attributed to factors like lack of
"theory of mind" or genetics.