Functional connectivity of EEG regional delta and inter-regional gamma activity correlates with memory recall

The main objective of this research was to investigate the association between electroencephalogram (EEG) and memory recall in human participant. A sample of 34 healthy participants was recruited and exposed to 10 minutes animated learning contents. After 30 minutes of the learning session, they performed a memory recall task; the correct and incorrect responses in recall task were recorded for computing the memory performance. EEG coherence was computed for six frequency band (delta, theta, alpha, beta, high-beta, and gamma) and the correlation was checked with the memory recall. It was found that the EEG delta coherence correlated (r=0.34-0.37; p-value<0.05) with the memory recall performance in frontal-parietal and frontal-occipital networks; while EEG gamma coherence was correlated with the memory recall performance (r=0.33-0.42; p-value <0.05) in widespread brain networks including all brain lobes. These results suggested that during memory recall process frontal lobe was communicating with parietal and occipital regions in low frequency band; while widespread multi-regions network was active in gamma frequency band.