I want to thank everyone who attended my address this morning. After untold amounts of airline trouble getting to Boston it was a real pleasure to have the chance to talk about the insula and interoceptive development.

If you are interested you can download a copy of my presentation slides here. Send me an email if you have any questions or comments. Thanks!

SUNDAY

• One of the best sessions on Sunday was a symposium discussing the integration of genetics, cognitive neuroscience, and psychology. It was hosted by an old friend of mine from grad school, Adam Green, and featured several top researchers in the field of cognitive neurogenetics. The findings that they were presented were quite interesting in terms of relating genetic variability to brain and behavior, but the most important part of the session was the feeling that genetics was going to be one of the ‘next big things’ in cognitive neuroscience. In the Miller Lab we have been able to identify roughly 50% of the variability in human episodic memory using behavior and functional imaging. Hearing now that the remaining 50% of variance may be genetic really makes me believe that this is something worth pursuing further.

Before this session there really hasn’t been a lot of discussion of genetic factors at CNS. It will be interesting to see how this evolves in the next several years. My prediction is that next year will see an uptick in the number of posters and presentations addressing genetic variability. Then, in two years there will be an explosion of posters and presentations incorporating genetic data.

Thought-provoking tidbit from the genetics session: Andreas Papassotiropoulos discussing the need to look for interactions in genetic data. Essentially, his point was that most current research is focused on finding direct gene to behavior correlations. He argued that there is the need to look at the influence of gene clusters to better understand how genetic factors interact.

• Marcus Raichle received the George A. Miller prize in cognitive neuroscience this year. He is a huge figure in the field of cognitive neuroscience – it is hard to think of a researcher more deserving of this honor. I was particularly excited to attend this lecture because I hadn’t seen Raichle speak before. I think it would be accurate to say that he is the father of ‘default mode’ research, a topic that is proving to be a rich area of inquiry. He did discuss default mode research in his talk, but the more interesting aspect of his lecture was the timeline he presented of how cognitive neuroscience and the cognitive neuroscience society came into being. He told stories of how the idea for the society was formed in the back of a taxicab, and how the startup funding for the society came from Mike Gazzaniga’s credit card. Cognitive neuroscience is a relatively young field, but that doesn’t mean that it lacks history. Raichle’s talk was a rare opportunity to learn how it came together many years ago.

MONDAY

My favorite session on Monday was the Emotion slide presentations, hosted by Kevin Ochsner. The slide presentations are a new addition to CNS that are designed to give outstanding research a wider audience. I think that it is a great change, and I appreciate that the CNS organizers continue to help the conference evolve to better serve the community.

• One excellent presentation was by Virginie Czernecki, a researcher with Inserm at Salpetriere Hospital in Paris. She showed data from a group of patients with insular damage demonstrating that they had deficits in unpleasant, irritating, and gustative emotion identification. The lesion focus of each patient was variable, limiting the spatial identification of what brain structure was causing the changes in behavior. Still, they showed the effects of insular damage across a range of tasks involving facial affect, odor identification, and working memory. Good stuff.

• Another presenter I wanted to mention was Tor Wager. He spoke on a re-analysis of a placebo analgesia dataset using a new multivariate analysis designed to identify functional networks of brain regions. I wanted to mention his talk primarily because it represented the best integration of technical imaging methods applied to an empirical question that I saw at the conference. Don’t get me wrong, there were many presentations that had worthy scientific investigations and many posters that had excellent new methods, but it is rare to see the two so well joined together. I think that his approach is quite analogous to how I hope to conduct my own research: a fusion of advanced methods applied to interesting questions.

• On Monday evening I went around the poster session doing a count of how many researchers used multiple comparisons correction in their analyses. George Wolford and I are wrapping up the final drafts of a new paper arguing in favor of correction and we wanted to get a feel for what percent of people are using it. Of the 42 posters that used a whole-brain, general linear model (GLM) approach only 9 posters used any kind of multiple comparisons correction. That’s rather sad. Worse was that some researchers who used techniques like FDR and FWE to do correction would sometimes revert to uncorrected stats if no activity was detected. I am trying to decide which is worse – not doing correction at all or doing correction only when it shows what you want. I think that our paper is going to hit at just the right time – now we just need to get it out.

TUESDAY

• The highlight of the day (personally) was the presentation of my poster at the morning session. Since it was a methods poster on the last day of the conference I wasn’t sure how many people would stop by. There is nothing more lonely than standing beside your research for two hours with nobody giving your title a second glance. I was fortunate this year in that I had a steady stream of folks stopping by, with some individuals quite interested. The research I presented had to do with the impact of experimental design on the ability to detect individual differences in fMRI activity. It turns out that some experimental designs may be better than others for getting at what makes us all different. Because experimental design is a topic of general interest I think the poster was able to pull in a diverse array of researchers who are looking to investigate individual differences. By any measure it was a very successful poster. Now, as always, the goal is to get it written up as a manuscript.

• The second highlight of the day was a talk on the representation of body postures by another friend from grad school, Emily Cross. She gave a great presentation on the separable roles of the mirror action system and the extrastriate body area. Also, she was one of the only researchers I saw all weekend who used a repetition suppression fMRI design in their research. Kudos to her for a great presentation.

OTHER NOTES

- The best part about attending conferences like CNS is the opportunity to catch up with friends and acquaintances from other academic institutions. Nobody in academia ever seems to stay put for very long, which makes reunions like CNS all the more special. The first night of the conference is a frenzy of people seeing each other for the first time in a long time. I love it.

- San Francisco is an amazing town. I have probably visited the city a dozen times and it never gets old. It is probably my favorite big city in the US. Which is good, because I have two more conferences there this spring.

- If you happen to find yourself in San Francisco you should eat at the House of Nanking, situated between Chinatown and North Beach. Simply amazing Asian/American food. I would also recommend Chow on Church Street in the Castro district. They have a real focus on healthy dining with an eye toward responsible cooking. The kicker is that the food is absolutely amazing. Check them out if you are around.

“The Integration of Higher Cognition and Internal State Across Development”
Bennett, CM. Doctoral Dissertation, Dartmouth College, 2008.
Bennett-Dissertation-2008.pdf

It is a large PDF file due to the numerous figures and tables included in the text. Keep in mind that the results and conclusions are still in a state of flux pending journal publication. Things may change quite a bit as each runs the gauntlet of the review process. Enjoy!

In brief, the conditions of his study were skilled-won, skilled-lost, unskilled-won, and unskilled-lost. These indicated whether the task involved strategy and whether you did better on each trial than another human completing the tasks outside the magnet. The region in orbital cortex didn’t change its activity level at all to the unskilled conditions. However, during the skilled conditions there was an increase in signal to the skilled-won condition and a relative decrease in signal in the skilled-lost condition. He argued that this represented social envy, because its activity only changed in conditions where a competitor’s skill impacted the outcome.

The confounding factor in this argument is that it involved a test of skill. You are no longer testing just the social comparison between yourself and a competitor, but also feedback signals from orbital cortex related to skill learning. In the skilled-lost condition you need to alter your behavior to a more optimal solution whereas in the skilled-won condition you need to reinforce the strategy and skills used. Some good papers related to this processing are Furuyashiki and Gallagher (2007) and Baxter et al. (2000).

I remain unconvinced regarding the argument for envy in orbitofrontal cortex. The skilled/unskilled comparison is not the best way to approach the problem. It also highlights a question I feel we should address as we examine our results: is there a more domain-general information processing ability that might explain the data? For this study I feel that the larger umbrella of skill learning could just as easily explain the results.

Refs

- Baxter MG, Parker A, Lindner CC, Izquierdo AD, Murray EA. (2000). Control of response selection by reinforcer value requires interaction of amygdala and orbital prefrontal cortex. Journal of Neuroscience, 20(11):4311-9.

- Coricelli G, Critchley HD, Joffily M, O’Doherty JP, Sirigu A, Dolan RJ. (2005). Regret and its avoidance: a neuroimaging study of choice behavior. Nature Neuroscience, 8(9):1255-62.

- Furuyashiki T, Gallagher M. (2007). Neural encoding in the orbitofrontal cortex related to goal-directed behavior. Annals of the New York Academy of Sciences, 1121:193-215.

Have you ever sat there and thought how your life would be much more complete if you could just learn more about interoceptive development? Well my friends, worry no more. By watching this video of my dissertation defense presentation you too can know far more about this amazing topic.

Title: “The Integration of Higher Cognition and Internal State Across Development”

The video is about an hour long and runs through four of my thesis experiments. You will hear my voice on the audio track and the video track displays the slides from my Keynote presentation. I had to use the internal microphone on my MacBook, so anytime I stray away from the lectern it gets a bit quiet. Still, it worked out rather well and I am happy to present it for your viewing.

Please to enjoy…

* View online at Google Video
* Downloadable Quicktime movie [~50MB]

Von Economo neurons are large bipolar cells that are found in cortical layer V of the anterior cingulate and fronto-insular regions. The cells have also been found in the gray matter of the ventral claustrum, near the amygdala. Originally discovered by Von Economo and Koskinas (1925) the cells are much larger [5x] than comparable layer V pyramidal cells. The size of these cells seems to indicate that they stand ready to send signals very quickly across long distances.

Von Economo cells are not ubiquitous across animal brains. Only humans, great apes, certain whales, and elephants have been shown to possess VENs. The relative number of cells varies by species, with humans having by far the greatest amount – over twice the number of our nearest evolutionary neighbor. One argument is that some aspect of VEN function is giving rise to the cognitive abilities that make us uniquely human.

Of interest developmentally is that not all Von Economo neurons are in place when we are born. Only 15% of the cells seem to be in place at birth. It takes several additional years for the number of cells to rise to adult-like levels. It is unknown if existing cell types are morphing into Von Economo neurons or if new neurons are migrating into place during this time. In either case, VEN development in somewhat protracted compared to other cell types.

In terms of pathology VENs seem to be particularly vulnerable to certain types of disease. In a paper by Seeley et al. (2006) they found that early fromtotemporal dementia resulted in a 74% loss of Von Economo neurons throughout the cingulate and insula. VENs that remained were dysmorphic and plagued with tau protein accumulation. Other neuron types were unaffected and a control group of Alzheimers patients did not show the same pattern of VEN loss.

What remains unknown is where the Von Economo neurons project to and what function(s) they support. Everybody likes to do some hand-waving in this regard. Some argue that VENs are projecting to frontopolar cortex, while others believe that VENs in the cingulate and insula are reciprocally connected. This anatomical uncertainty hasn’t stopped scientists from hypothesizing that these cells may (or may not) be linked to high-speed intuitive decision making and possibly higher-order social cognition. From my perspective there is still little support for this case and extrapolating region-level fMRI results to the function of a single cell type is going too far.

In summary I find Von Economo neurons very fascinating. Part of what draws me to cognitive neuroscience is the philosophical investigation into what processes make humans so unique compared to other animals. I do believe that the VENs are one part of this greater puzzle. I also want to believe that VENs play a role in intuitive thought and higher-order processes. However, I fear it will be some time before scientists are able to adequately demonstrate that link.

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References and further reading:

The Allman Lab website

Allman JM, Hakeem AY, and Watson KK. (2002) “Two Phylogenetic Specializations in the Human Brain.” The Neuroscientist, 8(4): 35-346.

Allman JM, Watson KK, Tetreault NA, and Hakeen AY. (2005). “Intuition and autism: a possible role for Von Economo neurons.” Trends in Cognitive Sciences. 9(8): 367-373.

Seeley WW, Carlin DA, Allman JM, Macedo MN, Bush C, Miller BL, Dearmond SJ. (2006). “Early frontotemporal dementia targets neurons unique to apes and humans.” Annals of Neurology. 60(6): 660-667.

Von Economo C, and Koskinas. (1925). “Die Cytoarchtectonik der Hirnrinde des erwachsenen Menschen.”