[Validation of the translation to Catalan and Spanish of cognitive evoked potential N400]

The cognitive evoked potential N400 permits an objective assessment of the verbal semantic processing. It has been suspected to be clinically useful in cognitive abnormalities and a correlation with attentional and memory functions has been found. The present study tries to validate the translation and adaptation of the English paradigm to the Catalan and Spanish languages.

The study was performed on 16 healthy volunteers with Catalan native language and 16 volunteers with Spanish native language. Three blocks of 50 sentences (4-9 words) were administered using headphones. The last word of 50 % of the sentences was incongruent. The beginning of this word was the trigger for the EEG average. EEG leads used were: Fz, Cz, Pz, C3, C4, T3, T4 with biauricular reference. The measures were amplitude and latency of the potential obtained after the subtraction of the EEG average of congruent and incongruent sentences. A t-test for one sample (the original potential) was applied.

Amplitude and latency of the potential obtained by the Catalan and Spanish languages were not result statistically different from the original potential. The major amplitude was obtained in Cz. Mean amplitudes: Catalan language: 5.3 2.3 V (95 % CI for the difference: 0.39 2.12 V); Spanish language: 5.2 2.3 V (95 % CI for the difference: 0.43 2.32 V).

The Catalan and Spanish version of the N400 evoked potential offer the possibility to use an objective instrument for the study of language in neuroscience.