Category Archives: neuropolitics

Game Theory of Mind

by Yunkyu Sohn

Traditional game theory assumes that the level of recursive belief inference is infinite when people choose their strategy as a result of guessing the others’ strategies. For example, in Keynesian beauty contest where all participants are asked to pick a number between 0 and 100 and win if one is the closest to 2/3 of population average, Nash equilibrium predicts all players should chose 0 since recursive inference about others’ preference will decrease the value of your choice, and eventually reach the minimum possible value. However studies in behavioral economics have found that the degree of recursion is bounded to smaller values.

By running a 2 dimensional stag-hunt game, recent fMRI experimental study done by Yoshida et al. demonstrates that people vary their level of inference depending on their partner’s past strategic profiles. Imaging result shows that prefrontal cortex region is subdivided by its roles for encoding uncertainty of inference of partner’s strategy and inferring the degree of recursive inference.

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Recent Abstracts

By Darren Schreiber

In this set of abstracts, we get some interesting evidence on why high sensation seekers might be drawn to scary movies (1) and a series of methodological innovations that demonstrate how new advances are going to improve our ability to get useful insights from MRI data (2, 5, 7, 8, 9, 114). We also have some new work illuminating the role of stereotyped racial judgments (which rely on the amgydala) and individuate judgments which use a broad network of regions connected with mentalizing (3). Another article shows that there is variation in the deactivations of some regions of the default mode network in particular types tasks (4). We also learn that the default mode network contains the most heavily functionally connected brain regions, with the posterior cingulate being particular well connected to the rest of the brain (10).

Another article melds structural and functional connectivity data to provide an exciting methodological innovation (11). I have long hoped that brain imaging statistical analysis would start to do better at accounting for our priors about how the brain is organized, specifically that techniques would be developed to take advantage of our knowledge of structure while we try to understand function. This paper is a great step in this direction and I know that the developers of the FSL package are also making strides towards this goal.

On the topic of connectivity, we have a study that used a structural connectivity technique to demonstrate that the amgydala appears to have at least three distinct subregions (5). The amgydala is also shown to vary in size in non-medicated bi-polar patients, controls, and medicated bipolar patients (6).

Rounding out the remainder, we have a nice paper that provides a possible explanation for why the anterior cingulate appears to be active in reward activity in non-human primates, but seems to be mostly involved in error prediction in humans (12). Another paper demonstrates an important lesson for economists about the distinction between monetary and social rewards (13). While we may anticipate them using the same region (striatum), consumption of those rewards implicates distinct regions. We also have some insight into mental fatigue that confirms the importance of rest and perhaps provides a way of understanding why we feel so depleted after a hard day of academic brain busting (14). The next to last paper tries to synthesize two literatures suggesting alternative functions for the anterior temporal lobe, suggesting that perhaps it is our attempt to integrate conceptual understanding of our social tasks that is activating the region (15). And finally, we’ve got a paper looking at a potential genetic role for face recognition and a demonstration that it is independent of general intelligence (16).

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Recent Abstracts (Part 2 of 2)

By Darren Schreiber

This selection contains some critical new work on extinguishing fear (18, 19, 20) that will be crucial for treating the veterans returning from our many conflicts overseas and for reducing the huge social costs of PTSD. Elizabeth Phelps has been doing some truly impressive work over the years, but this might turn out to be one of her most interesting discoveries. I’m also fascinated by the possibility the treating depression with SSRI’s implicates changes in personality, not merely mental illness (6). Given the role of personality in both political behavior and in general well-being, this work has some interesting social implications. It is also heartening to find additional evidence that measures of subjective well-being correspond well to objective indicators (9). And, since I always relish a nice hike in one of San Diego’s many fantastic parks, I’m glad to know that it might be having a positive effect on my generosity and seeking out of intrinsic rewards (13). On a darker note, the idea that insurgency has some predictable elements to it is an intriguing possibility (3, 4).

I was also interested to read about a new book on the coming era of “big data” (8) and since it was free online I’ve already downloaded and read some of the chapters that looked interesting. On the topic of the future of science, Nature’s asked some scholars to speculate about where their fields will be in a decade (17) and some exciting examples for future work in observing behavior (16) and modeling (15) are presented. I was also fascinated to read more about the possibility that the role of a gene might depend on who you inherited it from (12). When a colleague at the Santa Fe Institute was telling me about this over the summer, I was incredulous.

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Recent Abstracts (Part 1 of 2)

By Darren Schreiber

There have been so many interesting things published since my last update that I decided to split the list into two emails. In this collections, we’ve got the gamut from genes to neurotransmitters to brain to behavior. Crisan (1), Long (7), and Zak (13) show that neurochemistry (with serotonin and testosterone) alter economic decision making and Gan (20) provides evidence of the role for dopamine in encoding rewards. Decision-making is further illuminated with work on the nucleus accumbens (2), the temporo-parietal junction (12), and the orbitofrontal cortex (15). The insula and its roles in both internal (18) and social (3) perceptual process are also explored. Other highlights include discussions of the neural architecture of social reasoning (9), pain (10), attention (17), and Bayesian inference (19). I also think that the implications of new work on psychopaths (8) is fascinating as we try to synthesize our intuitions about legal and moral responsibility with work on the neuropathology that underpins this disease.

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Topological Efficiency of the Brain Network Determines Human Cognitive Ability

By Yunkyu Sohn

Some of the recent pieces relating the functional brain network topology and cognitive ability. Stam and Bullmore are two most active researchers applying network analysis into cognitive neuroscience.

Efficiency of Functional Brain Networks and Intellectual Performance

Cognitive fitness of cost-efficient brain functional networks

Recent Neuropolitics Abstracts

By Darren Schreiber

We’ve got lots of new work showing showing the role of the default mode network, specifically in social cognition (1, 3, 4, 8, 10).  While this was a speculation when I was writing about it five years ago, it seems to be quite cemented now.  We’ve also got a set of articles discussing reward processing (2, 6, 7).  I thought the overview piece on the Allen Brain Atlas was interesting (11).  Currently, the mouse brain is the most complete, but Wired Magazine had a fascinating piece about the work that is currently proceeding on doing the same thing for the human brain.

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Regions of Interest — The Amygdala

By Darren Schreiber

I’m testing out a potential new feature for the neuropolitics listserv entitled “Regions of Interest.” I’ll be giving a brief overview of a portion of the brain that is relevant to neuropolitics. I’ll include a few brain images that will help orient readers as to its location, a description, and a discussion of its relevance to the social cognition. I will then provide a set of citations to recent articles that discuss the region, with particular emphasis on interesting experiments, meta-analyses, and reviews.

I’m starting off with the amygdala. This region has become almost a household word in the past decade. The typical way it is discussed is in its role in the experience and processing of fear. However, the story is far more nuanced than that. This almond sized region is located in the limbic system, deep within the brain, as can be seen in the axial, coronal, and sagittal images shown above.

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