**2. Methodology**

The methods and protocols described herein were approved by the American University of Antigua College of Medicine Research Council which served as the University's Institutional Review Board (IRB). The study subjects provided their informed consent. A total of 10 male subjects were recruited; 1 subject discontinued the study due to his ill health. Females were excluded because of the potential confounding influence of hormonal changes associated with their menstrual cycles. Nine individuals underwent 5–10 minutes of eyes-closed (EC) qEEG measurements at 19 standard electrode sites [12–20]. The Brain Master Discovery System (Brain Master Technologies, Inc., Bedford, OH, USA) was used to take the qEEG readings 3 days before each of the first two summative block examinations covering standard firstsemester integrated basic science courses. For the purposes of this chapter, the qEEG voltage brain maps were selected for the subjects with the highest and lowest exam scores to demonstrate the spectrum of changes found to be associated with academic achievement.

The qEEG measurements were performed with subjects seated comfortably with their eyes-closed, in a dimly lit room. After manual editing with the New Mind Maps online editing tool (New Mind Technologies, Roswell, GA, USA), the mean ± SD of the voltage amplitudes, stated in μV, and the mode frequency in each bandwidth, expressed in Hz, were measured for the following standard qEEG frequencies: delta, theta, alpha,

#### *Quantitative Electroencephalography for Probing Cognitive and Behavioral Functions… DOI: http://dx.doi.org/10.5772/intechopen.107483*

and beta. The average theta-beta ratio of the voltages recorded at each of the 19 standard electrode sites was computed. All qEEG recordings were performed at the same time in the morning, after overnight fasting to avoid confounding factors related to food ingestion and metabolism. The subjects refrained from recreational drugs such as alcohol, marijuana, nicotine, and caffeine for the 24 hours before the qEEG recording session. None of the patients reported using prescription or recreational drugs within the previous month, according to self-report. Preliminary results suggest that eye opening, which is known to inhibit alpha brainwave voltage amplitude, resulted in changes in alpha voltage that were not uniformly reproducible. The qEEG measurements were therefore only interpreted for the closed-eye condition. Frontal alpha asymmetry (fAA) was computed from the mean alpha voltages at the frontal recording sites F7 (left) and F8 (right) as follows: ([F8 − F7]/F8 × 100). The inferior frontal gyrus is an area where "mirror neurons," hypothesized to process information about psychosocial interactions have been identified [21]. Negative asymmetry values are indicators of right-sided, nondominant hemispheric alpha asymmetry resulting from greater activation of the right frontal cortex. Negative fAA was defined as a qEEG recording where the average alpha voltage at the left frontal F7 scalp electrode was greater than the voltage at the symmetrical right frontal F8 scalp electrode. Positive asymmetry values are indicators of left-dominant hemisphere alpha asymmetry. Positive fAA was defined as qEEG where the mean alpha voltage at the right frontal F8 scalp electrode was greater than the voltage at the symmetrical left frontal F7 scalp electrode.

Within 8 hours of qEEG measurement, each study subject completed an Interactive Self-Report Inventory (ISI, New Mind Technologies, Roswell GA, USA) online at the New Mind Maps website (https://www.newmindmaps.com). For the purposes of this chapter, the ISI scoring of "depressed" psychosocial interactions was used to demonstrate the correlation and potential utility of the fAA measurement. Depressed individuals are expected to have had negative thoughts about themselves based on a correlation coefficient > 0.8 between relevant inventory items and the Beck's Depression Inventory (New Mind Technologies, Roswell GA, USA). For the purposes of this chapter, the qEEG asymmetry brain maps were selected for the subjects with the highest and lowest ISI "depressed" scores to demonstrate the spectrum of changes found to be associated with a subject's negative perceptions of their psychosocial interactions.
