The CNV: An Electrocortical Sign of Attention Or
Arousal
G.H. Blowers |
Contingent Negative Variation (CNV), an event related
slow EEG potential is thought to be influenced by `attention' because
of the nature .of the paradigm used to generate it. `Attention' can
describe selective attention or arousal-2 related but separate concepts.
Previous explanations of CNV in these terms are inadequate because
experimenters have failed to manipulate these variables independently.
This study employs an alternative design that enables predictions to
be made as to how different individuals' CNV's will vary in accordance
with their previously determined abilities to selectively attend and
to be aroused. Groups of subjects (`good' and `poor' selective attenders
and those with `high' and `low' arousal potential participated in a
CNV experiment involving a condition of distraction. Changes in CNV
amplitude were predicted such that a model could be formulated in terms
of selective attention or arousal but not both. While not conclusive,
the results favoured a model of CNV in terms of arousal.
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