I recently had the privilege to experience how an EEG (Electroenchephalogram) functions as well as an in depth look at the brainwaves that are present upon taking a EEG reading. I am currently enrolled in a Physiology lab, so being able to learn about the EEG in Psych 100 and then getting hands on experience with how the EEG worked greatly expanded my knowledge on the subject. From class we learned that the EEG works by measuring amplified brain waves through small electrodes placed on the scalp, but the actual complexity behind reading these brain waves is a little harder (at least for me) to understand.

The EEG reads the electrical currents that are constantly being sent through the nerves in your brain and even the rest of your body (as I will explain). The graph produced by the EEG is comprised of four different types of brain waves, Alpha, Beta, Theta, and Delta, but my experience deals only with Alpha and Beta brain waves. The first type is Alpha, and this brain wave indicates calm or unfocused behavior. If the subject shows a low amplitude (height of the wavelength) in their alpha wave reading, it means the subject is either stressed or focused/actively thinking. We would expect to see a high amplitude in the alpha waves of a subject who is calm and relaxed. To see this, I was required to keep my eyes open for a 30 second period and then closed for a 30 second period. Sure enough, when my eyes were closed my alpha brain waves were far more active, indicating that I was more calm with my eyes closed than with them open. In the second part of our lab, we were able to witness the change in Beta brain waves during the EEG reading. Beta waves, unlike Alpha waves, signal when the subject is actively thinking or focused on something. For this part of the lab, I performed basic arithmetic versus not thinking to demonstrate the change in Beta waves. Once again, I saw what I expected, which was that high amplitude (high activity) Beta waves were present when I was trying to solve math problems and low amplitude Beta waves were present while I was not solving math problems. From this, and what is true of Alpha waves, you have probably figured out that the height Alpha waves on an EEG reading are inversely proportional to the height of Beta waves. While this isn’t really a groundbreaking realization, I thought it was interesting to see the physical representation of what my brain is doing while performing certain actions.

The brain is a fascinating organ; we know less about how the brain works than we know about the known universe. However, the more we learn about trends in thinking through psychological research and the more we discover empirical evidence to support the process of these trends in thinking, the easier it will be to understand the most complex organ in our body.

-Derek Halko