Background: The Planning, Attention, Simultaneous and Successive (PASS) theory of intelligence allows us cognitive assessment. Hemoencephalography (HEG) allows us to assess cortical prefrontal activity. Reaction time (RT) allows us to assess decision-making. We aim to find teenager profile according to the PASS, HEG, and RT. Methods and findings: 59 secondary education adolescent students (30 females and 29 males, 14-16- year-old, mean=15.29, SD=0.67) were tested by two RT + HEG experiments. Stimuli of experiment 1 were cognitive and emotional dilemmas as displayed sentences or images. Stimuli of experiment 2 were shocking, unpleasant, and pleasant pictures with music or without music. PASS assessment was performed. We used oneway ANOVA (F-test) and correlation analysis. Longer reaction time was found in emotional dilemmas than cognitive items (p=0.000). The HEG activity deviation from baseline was not consistent in both cognitive and emotional processing and the statistically significant value showed remarkable variability. HEG-activity differences at statistically significant level between cognitive and emotional processing were not found, indicating that both cognitive and emotional tasks scored close together. All this means atypical pattern related to adult pattern. Poorer planning, attention, and successive was associated with poorer academic performance (p=0.00). Conclusion: A longer RT in emotional decision-making along with a simultaneously atypical HEG activity and all this associated with the relationship between poorer planning and poorer academic performance makes it reasonable that an imbalance between cognition and emotion in adolescence (relative to adulthood) contributes to adolescent personality. This imbalance is hypothesized to result in distinct patterns of activity shown in fMRI, and – we hypothesize – HEG in adolescence. Further HEG studies are needed