Kal is quite correct; I alluded to this in my initial post, but also to
behavioral studies showing some contralateral vs. ipsilateral
differences. To elaborate a bit: even if thresholds per se do not
differ between ears after a unilateral cortical lesion, input
contralateral to it may be suppressed somewhat when competing with
ipsilateral input (see my suggestion re looking at dichotic listening
studies).
To what extent this represents a more direct vs. more indirect input,
neuroanatomically, and to what extent this represents more general
lateralized attention effects (cf. experiments with loudspeakers rather
than earphones) is I think somewhat controversial, and I am not
knowledgeable about the latest conclusions--if any.
By the way: Kal, are you with NYU Center for Neural Science? if so,
give my regards to Joe LeDoux.
F. Frank LeFever, Ph.D.
New York Neuropsychology Group
In <6thteq$rra$1 at news.nyu.edu> kr4 at is2.nyu.edu (Kalman Rubinson)
writes:
>>Griffith A V Morgan (gmorgan at uoguelph.ca) wrote:
>> Comment:
>> Yes,there is a dominant ear. This was established years ago by
>> work such as that of Alfred Tomatis [Paris] on listening,the uterine
>> genesis of the vestibualr/auditory system. One obvious explanation
-the
>> human brain is specialized/localized for langauge functiong -areas
of the
>> left lobe which not only can be shown to process language
preferentailly
>> but show greater anatomical development. The left lobe receives
>> neurolgical input from the right ear,jus as the right lobe areas
receive
>> from the left ear.
>>This is not so. Above the brainstem, the projections to the thalamus
>and auditory cortex bear the input from both ears. They may not be
fully
>equal but lesions clealy affect threshholds on both sides.
>>Kal
>>