In this review I will discuss the contents of How Intelligence Happens, give potential readers some expectations before they begin and give some suggestions on how to read it. It is my expectation that this review will help readers decide if this book is appropriate for their research questions and/or personal interests.
Overall, I thought this was a wonderful book. It is well written and contains useful, relevant examples that are interspersed in the text. It made is easy to read and kept it from sounding like a textbook, as there is a fair share of factual information included. Duncan's writing style follows a general pattern. He often begins a chapter offering up his opinions or conclusions regarding the chapter's topic studies, providing a "big picture" look at the topic. He then goes into the specifics, often providing examples or revisiting examples and tying them together. Duncan generally uses a basic vocabulary when possible, making this book very easy to read without having to do any dictionary searches.
There are eight chapters, which are preceded by the prologue describing Duncan's central ideas and his motivation for writing the book. Each of the chapters has a general theme surrounding some aspect of intelligence, neuroscience and the combination of the two.
"Intelligence, the Brain and Free Will"
Duncan begins by describing the lure of this kind of study. As can be expected, searching for information regarding the nature of intelligence can be extremely interesting, controversial, and mysterious. Duncan begins with a discussion of intelligence, the "types" of intelligenc, and the history of intelligence testing. Duncan explains that there are obvious signs of what we consider intelligence, such as academic ability or memory. He also explains that while recent studies are strongly suggesting that all behavior is entirely biological, bringing up the age-old question of free will. However, Duncan firmly states that responsibility still lies with the individual. In regards to a proposed book explaining how people's brains make them do things that they shouldn't, he argues that he would prefer the title to read "Yes, It's Your Brain - But It's Still Your Fault." This is both an interesting and important way to start, in my opinion. Discussing the nature of intelligence can be highly controversial as the general public general assumes race is a determining factor. However, Duncan tends to be a little philosophical throughout the books and I felt this was one of those points. My purpose of reading this book was to learn more about the neurophysiology of intelligence so Duncan's ideas on free will and responsibility were of lesser interest to me.
"Types of Intelligent People"
Duncan delves into the types of intelligence found in people and how this explains their behavior. Strong correlations behind IQ, success in academia as well as success in the work force can be made, revealing a lot about an individuals potential. In addition to IQ tests, there are several exams that can be used to evaluate a person's intellect, such as Raven Matrices, which analyze logic skills, or multiple-battery assessments, which generate an average score based off an individual's scores from a variety of different tests. I found this section extremely interesting, as Duncan explained that Raven Matrices, which are eloquently basic puzzles, could provide the same information regarding intelligence as elaborate testing methods. I appreciated that Duncan provided a thorough background of previous works, the changes in how science views intelligence and how older studies had been built upon. Because this is a particular interest of mine, I did not mind all the details that Duncan included, however, most readers may find this part over extensive.
"Understanding the Brain"
Next, Duncan explains the important physiological structures of the brain, providing the necessary background information for discussing how the brain controls behavior, personality and what we consider intelligence. He then continues by connecting structures and types of intellect; specifically, the multiple-demand system. The multiple-demand system is a key component of higher thought and a constant topic throughout the book. While examining the multiple-demand system, Duncan suggest how the components of the brain could all possibly work together when it comes to producing cognitive thought and processing. He compares human cognition to artificial intelligence. While computers are capable of highly logical processing and analysis, well beyond the limits of human computing, humans are capable of stringing those ideas together, seeing the "bigger picture." Duncan also discusses the frontal lobe studies done on monkeys that let to the identification of cells and neurons responsible for decisions, delving into the neurophysiology of intelligent thought.
For those who haven't studied the brains anatomy, this will be an extremely useful section. It may be beneficial to do some background searching or to follow along with an online resource, as having visual aids will help. I enjoyed the level of detail that Duncan provided, as it was sufficient to understand his point without being overly scientific. The examples that Duncan uses in this section are also very interesting, as he discusses many very fascinating cases of psychological disorders and their relationship to changes in the brain.
One of my favorite parts of this book involved Duncan's discussion of cognitive dissonance. The short and long of it is that we are extremely biased to the point that our brains will alter the way we perceive information to better support ourselves. One of Duncan's examples was "The fox wants the grapes until it is clear that they will not be obtained...he reasons that those grapes were not so wonderful after all..." Looking into my own life and decisions, I can think of clear examples of when I have gone through this sort of thinking myself.
"The Future of Intelligence Research"
Duncan concludes by stating that the one sure thing in these sorts of studies is change. What he means by this is that what is generally accepted now will change as research progress and we are at this point [of understanding intelligence] now but will be racing ahead with new knowledge and discoveries into the future.
Because I have studied neuroscience and psychology, some of the information was review. However, a lot was a new way to look at things I had heard before. I thoroughly enjoyed reading the book and would suggest it to anyone looking for a way to start understanding the neurophysiology of intelligence. As a recommendation for potential readers, I would say that the book is easy enough to read without a background in this topic but being familiar with basic psychology and neurophysiology will certainly help. I would also state that having a basic understanding of how research (particularly on animals) will make the examples and cited studies more meaningful.