[Event related brain potentials and imageability effect in the semantic processing].
BACKGROUND
Event-related brain potentials (ERPs) are a useful measure of the brain activity underlying linguistic processing. They can also be used to study cognitive/linguistic impairment in different neurological diseases. To do this, it is necessary to know which electrophysiological components are related to relevant linguistic parameters, and the characteristics of these components. One of these parameters is the dimension of concrete-abstract or imageability.


OBJECTIVE
To find electrophysiological evidence for differential processing of concrete vs abstract verbal material, in the absence of brain damage.


METHODS
The short, semantically congruent sentences used were made up of high or low imageability (HI/LI) verbs followed by HI/LI complements. We also manipulated close probability in the case of the complement. Sentences were shown word by word and participants were asked to make an imageability judgement. Electrophysiological recording during verb and final complement were analysed in ten subjects.


RESULTS
Electrophysiological recording obtained during verb presentation show an imageability effect starting at 350 ms (especially in the N400 component) with no differential scalp distribution. There is a similar tendency in the recordings of final complements, although differences in imageability are not statistically significant.


CONCLUSIONS
These results suggest the existence of an imageability effect in the ERPs associated with semantic processing in semantically congruent sentences and that this effect is produced when the verb is presented.
Duarte-Expósito
M J
MJ
Universidad de la Laguna, Facultad de Psicología, Santa Cruz de Tenerife, Canarias, Spain.
Nieto-Barco
A
A
de Vega-Rodríguez
M
M
Barroso-Ribal
J
J
D000328:Adult; D004569:Electroencephalography; D005071:Evoked Potentials / Q000502:physiology*; D005260:Female; D006801:Humans; D007092:Imagination / Q000502:physiology*; D008297:Male; D008606:Mental Processes / Q000502:physiology*; D012660:Semantics