No, not where ARE you when you think of yourself. Where does it happen? What part of the brain? This question has become very important to the world of cognitive neuroscience recently. We used to think of self-reflection as taking place only in the prefrontal cortex. This would mean that only animals with a well-developed prefrontal cortex would be capable of self-reflection. However, another brain area has recently been implicated in self-reflection, the insula.
The insula is hot in neuroscience right now. It’s a weird little bit of your brain, a bit of cortex that is actually INSIDE the rest of your cortex. We all know that the human brain is full of folds, known as sulci. One of the most obvious sulci is the lateral sulcus, located between the frontal lob and the termporal lobe, just above your ears:
In this picture, your face is on the left side of the screen. That bottom bulge which would occur around your ears is the temporal lobe, which is separated from the base of the brain by the lateral sulcus.
So what does this have to do with the insula? Well the insula is INSIDE the lateral sulcus. It’s very deep, and on a human brain you can actually pry it open pretty easily. Inside the lateral sulcus are these clear stripes of cortex, your insula.
There it is all pried apart so you can see it.
The insula has gotten a lot of attention recently. It first appeared on Sci’s radar when a study came out in which smokers with lesions of the anterior (front) insula suddenly lost all urge to smoke. It’s also known to be involved in social thinking. But now a new study has come out, showing that it also plays a role in self-reflection.
Modinos et al. “Activation of anterior insula during self-reflection” PLoS ONE, Feb. 2009.
Why is self-reflection important? Well, in social animals (like us), self-awareness, and thus self-reflection, are pretty critically important for doing things like determining your place in a social hierarchy. Not only that, they are important for differentiating yourself from your environment and from others around you.
To me, before I read this, differentiating yourself from your environment was just something that HAPPENED, you know? Of course I’m not my environment, or the people around me. I’m ME. But apparently there are some people who have a great deal of trouble differentiating themselves from others and their environment. This “impaired self-awareness” is one of the signs of psychosis, which is often seen in schizophrenia. So finding out where self-reflection takes place could give us places to look in people who have psychosis, which could give us targets for helping them out.
So let’s get to it.
One of the reasons I like this study, by the way, is because fMRI, however flawed as a technique, yields some truly awesome pics. I am lifting them gently from the paper and placing them in this post, and if PLoS ONE comes to get me, it is easier to ask forgiveness than permission, and I am so very, very sorry.
So what they did was take a person, and stick them in an MRI. They then had them think of three things:
1) Themselves. They had to take a test looking at short statements and choosing whether it described them or not. The statements were your basic personality test statements, like “I am a good friend”, “I often forget things”, etc.
2) Someone they knew. Same test, only they had to say whether the statement was true as it related to someone they knew.
3) Something random. This test was a list of facts, such as “you need water to live” or “spring comes after autumn” which the participants had to rate as true or false. They had this condition in there to rule out activation due to basic cognition and decision making.
So what did they find? It turned out that all three tasts activated basic areas of the brain for vision (seeing the test), decision making, and cognition. Lots of activation in the anterior cingulate cortex, the prefrontal cortex (especially the middle and superior frontal gyri).
What you can see here is various areas activated by all three tasks. on the upper right in the back of the brain with a ton of activation in the occipital cortex, which is the area for primary visual processing. The upper left shoes little spots of activation in the middle frontal gyri, which is involved in decision making.
So we know what all three tasks activated. What was different about the self-reflection task?
That bottom brain slice is particular is just gorgeous. The cross-hairs indicate the anterior insula, which was the one major area of the brain which correlated only with self-reflection, not with reflection about someone else or with reflection on facts and decision making. They also found that the precuneus was only active during reflection on other people:
Another lovely picture, that. The yellow part near the rear of the brain shows the precuneus, activated only while the participants were thinking of other people, but not of facts or themselves. From this study, the authors primarily concluded that the anterior insula may play a role in the sense of self. This means that problems with the anterior insula could contribute to problems in people with psychosis, or other emotional or social problems. They also found some activation in the superior temporal gyrus (the area right next to the insula on the outside of the brain, which is an area that we believe to be important in social thinking.
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The authors did bring up a couple of issues with this study, and I agree with most of them. The authors believe that the insult in particular relates to self-reflection rather than something like emotional processing, because they used a test that was not designed to cause emotional states (like looking at emotional pictures might have), though the personal statements still could have elicited some emotional response. However, the anterior insula has been implicated in emotional processing, and though they didn’t deliberately elicit emotion with their task, self-reflection will probably elicit some strong emotions. There’s probably no real way to control for that, though it’d be really cool to see a study on complacent self-reflection (“I’m SO awesome”) vs negative self-reflection (“I totally suck”). Not only that, such a study would be very useful in understanding of depression, a disorder characterized by excessive negative self-reflection.
I would also like to know if they specifically asked the participants to pick another person to think about that didn’t elicit emotion. When I am asked to think of someone I know, I will immediately think of someone that I am either close to, or totally despise, unless instructed otherwise, and I’m sure I’m not alone in that. I wonder if they could divide the responses based on how the participants felt about the person they were thinking of? Perhaps that will be the next study.
Finally, the authors noted that they didn’t control for social desirability in the self- and other- reflections. So basically, this means they didn’t control for whether or not people would be likely to lie or delude themselves in some of their answers. So maybe some different questions would be in order for the next study.
In general, though, this is a great study, and gives scientists new brain areas to look to when looking for problems with emotional processing and self-reflection. And now you know where in your brain you are, when you’re thinking about yourself.
Gemma Modinos, Johan Ormel, André Aleman (2009). Activation of Anterior Insula during Self-Reflection PLoS ONE, 4 (2) DOI: 10.1371/journal.pone.0004618
