The validity of linguistic specificity for N400 component in cognitive visual evoked potentials technique using a Romanian psycho-verbal stimulation interface

The experiment aims to demonstrate the validity of linguistic specificity for N400 component in cognitive visual evoked potentials technique whatever is the level and the strategy of decoding, using a Romanian patented psycho-verbal stimulation interface. The acquisition of visual evoked potentials was performed in Cz, Pz, Fz, Oz leads, using a group of 50 adult persons between 19–21 year old, students who made two recognition tasks using decoded of 500 strings of symbols and decoding 500 strings of letters (words and non-word) with an average number of 7 characters. EPs were analyzed in a 1000 ms interval, after it used Grand AVG function for 50 person's recordings at each task, on 17 of 100 ms interspersed intervals, looking through SPSS software using ANOVA method which assess the highest difference in amplitude for each interval. Averaged EPs was poor in component after 300 ms for non-linguistic strings of symbols, but for linguistic stimuli it appeared a pronounced negative wave between 350–450 ms (t=6.25, p<0.001) and others negative and positive reverberation was present after this latency (t=1.10, p>0.05), especially in Fz and Pz. P300 was present on both tasks. The N400 component is related with linguistic stimuli, regardless of semantic or non-semantic types (pseudo - words) which confirm the findings of other studies.