• brain dynamics
• cognitive performance
• EEG
• flickering light stimuli
• working memory

Modern day society demands trigger emotional and mental stress that are the precur-
sors to the more frequent cases of burnout and mental fatigue. The ever increasing workload
results in a physical and emotional exhaustion. These negative factors are detrimental to cog-
nitive functions such as attention, memory, perception and decision making. Existing brain
wave entrainment applications have shown good results in enhancing cognitive performance by
a prolonged exposure to a visual or auditory stimulus in a quiet environment. Furthermore,
previous research has revealed characteristic patterns of spatio-temporal activity over cortical
and sub-cortical areas distributed throughout the EEG spectrum in response to a variety of
cognitive tasks. In order to test the possibility to enhance cognitive performance by applying
a visual stimulation, we investigated how and what brain-wave dynamics are involved in work-
ing memory processing by analyzing the changes in the EEG signal power while a subject is
performing the n-back task. Results show that Theta, Alpha and Beta rhythm are involved in
cognitive processing. Correlations between Theta, Alpha and Beta power trend patterns and
performance have been found. In particular, we found a positive correlation between the Beta
band power level before the task onset and the reaction time. This suggests that a lower Beta
band prestimulus level can enhance the performance of a subject.