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University School of Medicine.
New York University
private university in the public service
First Avenue, Suite 7D
New York, NY 10016
(212) 263-6287 Fax:
Larry Vidimsky DOB:
by: Dr. Gulati
examination: Evaluation of visual capabilities
Neurometric evaluation included a twenty minute recording of eyes
closed, resting EEG recorded from standardized electrode positions over
19 brain regions while the subject sat blindfolded, initially at rest
(condition A) and then while trying to read while his eyes were covered
with a blindfold (condition B). After visual inspection of each EEG
record, two minutes of artifact-free data were selected from A and from
B for quantitative (QEEG) analysis.
addition, in both conditions A and B:
potentials (VEPs) were elicited by binocular visual
pattern reversal stimuli.
EEG in condition A was of relatively low amplitude. The QEEG shows the
frequency distribution expected from a normal child 11.2 years of age,
when recorded at rest with eyes closed and essentially all quantitative
values were well within normal limits. There was the expected peak at
10.53 Hz in the middle of the so-called “alpha” frequency band, with
maximum values as expected in the visual cortical regions. The
generators of this frequency were shown by three–dimensional source
localization to be in the bilateral occipital and temporal gyri and the
bilateral inferior frontal cortex.
EEG in condition B shows a completely different frequency distribution
characterized by very large electromyogram activity (EMG) in all
regions of the prefrontal cortex and the anterior temporal lobes. The
QEEG reveals a great anterior excess of beta activity in those regions.
There are large peaks of beta activity (133-18 Hz in the periorbital,
dorsolateral and mesial prefrontal cortex, consistent with wrinkling
the forehead and squinting the eyes. There are no signs of
activation in the visual associations
regions (posterior temporal and parietal cortex) or in the primary
visual (occipital) cortex. The generators of these beta frequencies
were shown by three–dimensional source localization to be in the
bilateral prefrontal and temporal regions associated with jaw clenching
and forehead-eyelid muscle contraction, but there was no
sign of activation of the readings required to mediate reading or
visual scene analysis.
normal VEPs were elicited by the pattern reversing visual field in the
eyes open condition A, with morphology and topographic distribution as
expected from a normal child when tested
with open eyes. Inexplicably,
a strong and well replicated VEP was detected in the occipital regions
in two replicated trials with the eyes blindfolded, in condition B.
Copies of these VEPs are provided herewith.
conventional EEG, QEEG and brain imaging all indicate strong activation
of the frontalis, obicularis and temporalis muscles during the periods
when the child was attempting to read. There was no indication that the
brain regions concerned with processing visual information were
activated during these endeavors in condition B.
clear, morphologically and topographically normal visual evoked
potentials were elicited in with eyes open as well as blind-folded. We found no evidence from brain imaging that
indicated any input to the visual regions while blindfolded.
E. Roy John, Ph.D.