Visual evoked response

Visual evoked potentials were elicited by tachistoscopic
presentation of familiar (real words) and novel (pseudowords)
verbal stimuli to young and elderly adults. The amplitude
and latency of the P300 component did not differ significantly
for any of the experimental conditions. Excessive
noise in the averaged waveforms, most likely due to eye
and motor contaminants, may have been partly responsible
for the failure to confirm the hypotheses.

Visual average evoked potentials (AEPs) were recorded
from four male Ss in a sequential, single digit problem
solving task requiring addition of the first digit to the
second. Separate AEPs for the first and second digits
allowed Late Positive Component comparisons. It was
hypothesized that LPC latency variations are a function of
cognitive evaluation of information, with the prediction
that there would be a normal latency LPC in the first digit
AEP, where S recognizes a stimulus, as compared to a
delayed LPC in the second digit AEP where S must both
recognize and cognitively evaluate information to solve
the addition problem. Two experimental conditions, varying
stimulus presentation time between long and short, were run.
Equipment failure terminated the experiment and the
proposed study could not be researched. The pilot data
gathered were too variable and incomplete to permit conclusions.
However, these data did not contradict the hypothesis.