Above: Dr. Joe Kable lecturing on applied neuroscience.
T G I … fMRI. It’s Friday at Penn, and that means we’ve completed five days of boot camp. I think most participants felt the week flew by, and I also think most of us are happy that we’re about to get a day and a half to rest. Today we heard a series of lectures on social-affective neuroscience from Dr. Joe Kable. Neuroscience, he showed us, has been applied in a number of creative ways, including the Coke vs. Pepsi debate, how couples feel each other’s pain, and the perception of wine quality.
Despite the innovative methods of the studies, however, there is still open debate about the extent to which imaging research can improve the amount of variance we can explain already with behavioral studies. Basic science need not be concerned about the applications of their work, but for a room full of non-scientists, the “So how can this help research in my area?” question is central. Answering that question will require continued dialogue between neuroscientists and non-neuroscientists, and it’s my hope is that forums such as this Boot Camp continue to bring us together. (Click below for more).
The morning started with Martha Farah giving us a very helpful “Where have we covered so far, where are we going next?” review. Neuroscience, she reminded us, uses multiple methods to study multiple levels of observation. No single method nor single level is the gold standard; rather, each method has strengths/weaknesses, and increasingly the neuroscience community is look to see how different methods can be used together to infer how systems of the brain work together and enable behavior. (In this way, neuroscience is quite like the social sciences, where we try to triangulate with multiple methods and data sources).
After Martha’s brief comments, Joe Kable took center-stage. Joe wins an award for endurance, as he lectured and answered questions from morning to evening. We covered a wide swath of topics, all having to do with the ways that neuroscience may be applied to better understand human decision-making in a variety of contexts. We started by covering emotion, then moved to reward systems and negative affect. Joe gave us an overview of executive function and how the Prefrontal Cortex (PFC) operates. In the afternoon sessions, he covered applied neuroscience in the areas of addiction, consumer choice, preferences, social perception, empathy, and Theory of Mind. As you can probably tell just by the length of that list, we covered a lot!
II. Important Lessons
The first lesson of the day was one of the most important in terms of getting the anatomy straight: there is no “emotion box” in the brain. There are specific brain areas for specific affective processes, but all the emotion neurons are not all anatomically clustered in one area of the brain. An older theory of emotion (the “Limbic system hypothesis”) had posited such an area. Allowing for specific areas related to specific processes lays the groundwork for identifying those relationships. We covered two important processes: (1) the relationship between dopamine and reward systems; and (2) the amygdala and fear response. I won’t reproduce the details here, but you can find user-friendly summaries online here for rewards and here for fear.
To get a flavor of what we did next, click here and take the stroop test. Did you do it? If so, or if you have before, you’re making good use of your Prefrontal Cortex (PFC). Through lesion studies (when someone’s PFC is damaged), we learned that they perform worse on these tests and others that require executive function.
Executive functions are what we think of as actions that are controlled (instead of automatic) or goal-directed (instead of habitual). Lesion research, where you look at the differences between patients with localized lesions and normal controls, have found that the Prefontal Cortex is responsible for much of our executive functioning.
How does the PFC operate? One way is to mediate the response of other pathways. Consider this example provided in lecture. When the phone rings, a response has to happen determining whether or not you answer it. In this case the PFC may mediate the strong response pathway, so that rather than simply seeing phone rings --> answer phone, the PFC (which is goal-directed, perhaps here to the goal of being socially appropriate) mediates by determining if the phone ringing is your phone or someone else’s phone. If it’s someone else’s phone, then the PFC will mediate the pathway such that you don’t answer this other person’s phone. That overly simplified example doesn’t capture the complexity of the brain’s signaling system, but the take-home point is that the PFC is often involved in executive functioning, e.g. self-control seems to be related to activity in the dorsolateral PFC. If nothing else after boot camp, I will now be able to use a little brain language the next time someone talks about their diet plans.
When we turned to applied neuroscience in the afternoon, we went through a large number of studies in fields such as neuroeconomics. Each area of applied neuroscience invites further discussion beyond this blog post, but as a general observation you should know that many questions we might like neuroscience to address simply don’t have answer yet. This is what we should expect with a technology and field that is still so nascent, but when we see beautiful fMRI images we often (or at least I do) impute to applied neuroscience a precision that it has not yet achieved.
III. Who’s at boot camp with me?
Since we covered a few neuroeconomics pieces today, it’s a good day to mention that two graduate students from Harvard’s Economics Department are here. Adam Clark-Joseph and Johanna Mollerstrom have both been great to have in the group, as they give us economist expertise.