I had already been exposed to most of the topics discussed in this psychology course in my high-school class; though in much less depth. Because of this, the most interesting and likely the most memorable topic discussed in this class was one that I had no previous exposure to, split-brain studies.
Split-brain studies are carried out on patients with an extreme form of epilepsy. To combat severe seizures, patients have the corpus callosum (neuron fibers connecting their right and left hemispheres of their brains) severed. The results puts an end to the debilitating seizures and gave researches the unique opportunity to study the different functions of each hemisphere of the brain. What I found particularly interesting was the role of speech comprehension and the "little voice in our head."
To study the effects, scientists set up experiments that asked split-brain patients to recognize images in their left field of vision. The images were sent to the right hemisphere of the brain but since the corpus callosum is severed, it is unable to share what it sees with the left hemisphere which controls speech comprehension. The result is that the patient is unable to say what it is exactly they see yet the information is still stored in their brain. Later when asked to draw what they saw with their left hand (which is controlled by the right side of their brain which "saw" the image) they draw similar images to what was in their field of vision. When asked to explain what they were drawing, the subjects often made up stories.
This video was shown in class and does a very good job explaining how the experiments work.
What I took away from these studies was that the little voice in our head isn't what's really in control. It is simply rationalizing and explaining what is going on in the other parts of our brain which are really making the decisions.
Here is a link where you can play a split-brain game!