bulgarian journal of plant physiology2005Vol. 26pp. 173-188
149
brtolo2005psicolgicavisual
Abstract
The question regarding visual imagery and visual perception remain an open
issue. Many studies have tried to understand if the two processes share the
same mechanisms or if they are independent, using different neural
substrates. Most research has been directed towards the need of activation of
primary visual areas during imagery. Here we review some of the works
providing evidence for both claims. It seems that studying visual imagery in
blind subjects can be used as a way of answering some of those questions,
namely if it is possible to have visual imagery without visual perception.
We present results from the work of our group using visual activation in
dreams and its relation with EEGs spectral components, showing that
congenitally blind have visual contents in their dreams and are able to draw
them; furthermore their Visual Activation Index is negatively correlated with
EEG alpha power. This study supports the hypothesis that it is possible to
have visual imagery without visual experience.