Two Heads

Two Heads is a delightful “exploration of how our brains work with other brains” composed in a beautifully illustrated format. The main protagonists are cognitive science emeritus professors Uta and Chris Frith, who are also married to each other. Their son, Alex, is an established non-fiction author of books aimed at children. Not to worry if you don’t know anything about brains or neuroscience. They teach you as you read along. And each chapter is masterfully connected to the next so you just want to keep going!

 

While I was familiar with a number of the classic experiments they describe, there were more than enough new things for me to mull over. One that really caught my attention was over-imitation. Many animals learn through imitation, as do humans. Children are imitating what they see and hear all the time! Both children and adults also learn through being taught something explicitly – the basis for setting up an education system! But the interesting part is that when we first learn something, we do it through over-imitation. Instead of just copying, we try to copy exactly. I see this all the time when teaching chemistry, especially because the subject matter is often counter-intuitive.

 

Why do humans over-imitate? (Apes don’t, apparently.) The Friths argue that it’s for social reasons: “We do it because this is the way our group does things, and we want to fit in with out group.” And sometimes we do the opposite: “Deliberately not over-imitating can be a way to mark ourselves part of one group rather than another.”( Interestingly, some autistic kids tend not to over-imitate.) But there’s more. We don’t often notice that we have a tendency to imitate someone who seem more like us (the in-group) rather than someone who seems more different (the out-group). I wonder how that impacts the teaching-learning nexus. As someone who grew up in a different country but who now teaches (mostly) Americans between the ages of 18-22, and who has a noticeable accent when speaking English, I wonder if and how that affects the subconscious parts of student learning in the classroom.

 

There’s an interesting chapter about how the brain recognizes self from other. Apparently, you can tickle yourself if you use a double-robot arm contraption where the second robot arm has a time delay response. Weird. And sometimes the feedback self-recognition loop can break down, and we see this manifested in certain types of delusions, hearing voices, and schizophrenia. Apparently, schizophrenics can often tickle themselves. This discussion leads to the famous experiments by Benjamin Libet – before taking an action, the brain activity can be observed before one consciously recognizes the decision to take the action –  which brings up questions of free-will. The Friths think that interpreting “that your body moves, then your brain retroactively decides that the movement was deliberate” is incorrect. Instead, “your brain predicts it is going to move, then compares the final movement with the prediction. Only after the prediction has been tested does the movement get logged by your brain as a deliberate movement. It’s a quirk of biophysics that this operation takes an amount of time that can be observed and measured.”

 

I’d been thinking along those lines after reading Robert Rosen’s Anticipatory Systems. I think an interesting way to characterize life is that it’s an anticipatory system whose function cannot be cleanly separated from its genesis. Evolution of the brain is to improve anticipatory ability, particularly when it comes to social interactions – at least that’s what I gather from reading Terrence Deacon. This fits well with the overall discussion in Two Heads, and much of the book focuses on the social aspects of cognition of neuroscience. Early in the first chapter, they explicitly say that “your brain is a Bayesian prediction engine”.

 

Halfway through the book there is an interlude chapter discussing how challenging some of these psychology experiments can be with their many limitations and pitfalls. It can be so tempting to over-interpret the data towards pre-conceived notions or something that will be media-buzzworthy. There’s also an interesting section describing a collaboration with an anthropologist who studied what happens at a research institute and compares it to “a Georgian house, where this is a clear hierarchy of people, and set rooms for set tasks. The overall task of the house is to turn nature into science…”

 

Another potential take-home message from the book is that collaboration leads to better outcomes but there’s a caveat: The collaborators need to have similar levels of competency and also similar levels of confidence. There’s also some evidence that diversity improves the outcome. The experiments described are limited so I don’t know how well those conclusions extend to broader settings, but I’m certainly seeing the business world use these ideas to create buzz. I also liked how the Friths’ conclusion, as psychologists, that most people are instinctively nice (because of reputation and group dynamics) in contrast to a purely homo economicus view.  But they also acknowledge that in-group and out-group factors can complicate things.

 

Overall, if learning about the brain, cognition, and social psychology, is something you’re interested in, I recommend Two Heads. It’s an engaging book that threads the needle between giving you the details (without being overwhelming) and the big picture (with examples that you might care about). Overall two thumbs up.