The Uses of Reason

Honestly, when I was reading this chapter, I didn't feel as drawn in as I did when I was reading previous chapters. I'm not sure why, I just wasn't as interested.

Anyway, Lehrer dedicates this chapter to a discussion of the human prefrontal cortex, the rational part of the human brain. The prefrontal cortex essentially controls our emotions and prevents us from succumbing to our most immediate urges. This part of the brain allows us to regulate our emotions by allowing us to think about them, an ability that psychologists call metacognition. The prefrontal cortex lets us reject the first impression, as demonstrated in the Stroop test. The prefrontal cortex tells us to ignore the obvious answer, the word, and allows us to identify the color in the text. I tried doing the test and it really was difficult to name the text color. It took me a while to work my way down the whole image.

Our prefrontal cortex also enables us solve problems. In my opinion, this explanation was the most interesting part of the chapter. Our prefrontal cortex has a working memory. As our brain reacts to a stimulus, neurons in the brain fire. However, even as the stimulus is removed, the neurons continue firing for a short period of time, usually a couple of seconds, leaving an echo in the prefrontal cortex's working memory. As the next stimulus comes in, the neural signals overlap in the working memory, allowing new associations to form. This explains our "aha!" moments. Once these new associations are formed with the brain, we realize that these could be the solutions to our problems.

I thought the bit about how the prefrontal cortex was illuminating. It explained how we problem solve, as well as demonstrated the rational powers of the prefrontal cortex.

I hope the next chapters are a little more interesting than this one. I'm not saying that this wasn't interesting, I just didn't feel like it was up to par with the previous chapters that I read.

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