Incorrect Performance and Slow EEG Frequency in Specific Brain Areas

Abstract:
This study was aimed at demonstrating that incorrect performance is associated with slow EEG frequency preceding stimulus presentation over scalp regions that are task-specific. EEG 10-20 recordings were obtained from 44 normal 8-10 year-old children during the performance of 3 tasks: Continuous Performance Task (CPT), Verbal Working Memory Task (VWMT), and Word Categorization Task (WCT). EEG segments of 1280 ms immediately preceding stimulus were separately selected for correct and incorrect responses. For each lead the power in the delta, theta, alpha, and beta bands was obtained. Incorrect responses were preceded by lower alpha power than correct responses at: P4,T5,T6 in the CPT; Fp1,Fp2,F4,F7 in the VWMT; and F3,F7,T3,T5,O1 in the WCT. Greater delta power was also observed in CPT over Fp1,Fp2,F7,F8 and C4. Behavioral results suggested practice effects and absence of fatigue along the experiment; there were no significant differences in reaction time between correct and incorrect responses. Because decreased arousal level is characterized by generalized slow activity, it may be concluded that the slower EEG activity previous to stimulus presentation in task-specific brain areas could be responsible for incorrect performance on each task, independently from arousal level. Acknowledgements: DGAPA (grant IN214295) and CONACyt (grant 1028P-H)