Biochemical specificity of von economo neurons in hominoids
Article first published online: 7 DEC 2010
Copyright © 2010 Wiley-Liss, Inc.
American Journal of Human Biology
Special Issue: 2010 Wiley-Liss Plenary Session on Human Biology and the Brain
Volume 23, Issue 1, pages 22–28, January/February 2011
How to Cite
Stimpson, C. D., Tetreault, N. A., Allman, J. M., Jacobs, B., Butti, C., Hof, P. R. and Sherwood, C. C. (2011), Biochemical specificity of von economo neurons in hominoids. Am. J. Hum. Biol., 23: 22–28. doi: 10.1002/ajhb.21135
- Issue published online: 10 DEC 2010
- Article first published online: 7 DEC 2010
- Manuscript Accepted: 18 OCT 2010
- Manuscript Revised: 13 OCT 2010
- Manuscript Received: 29 SEP 2010
- Great Ape Aging Project (NIH). Grant Number: AG14308
- National Science Foundation. Grant Numbers: BCS-0515484, BCS-0549117, BCS-0827531, DGE-0801634
- National Institutes of Health. Grant Number: NS42867
- James S. McDonnell Foundation. Grant Number: 22002078
- Foundation for Comparative and Conservation Biology
- Cleveland Metroparks Zoo
Objectives: Von Economo neurons (VENs) are defined by their thin, elongated cell body and long dendrites projecting from apical and basal ends. These distinctive neurons are mostly present in anterior cingulate (ACC) and fronto-insular (FI) cortex, with particularly high densities in cetaceans, elephants, and hominoid primates (i.e., humans and apes). This distribution suggests that VENs contribute to specializations of neural circuits in species that share both large brain size and complex social cognition, possibly representing an adaptation to rapidly relay socially-relevant information over long distances across the brain. Recent evidence indicates that unique patterns of protein expression may also characterize VENs, particularly involving molecules that are known to regulate gut and immune function.
Methods: In this study, we used quantitative stereologic methods to examine the expression of three such proteins that are localized in VENs—activating-transcription factor 3 (ATF3), interleukin 4 receptor (IL4Rα), and neuromedin B (NMB). We quantified immunoreactivity against these proteins in different morphological classes of ACC layer V neurons of hominoids.
Results:Among the different neuron types analyzed (pyramidal, VEN, fork, enveloping, and other multipolar), VENs showed the greatest percentage that displayed immunostaining. Additionally, a higher proportion of VENs in humans were immunoreactive to ATF3, IL4Rα, and NMB than in other apes. No other ACC layer V neuron type displayed a significant species difference in the percentage of immunoreactive neurons.
Conclusions: These findings demonstrate that phylogenetic variation exists in the protein expression profile of VENs, suggesting that humans might have evolved biochemical specializations for enhanced interoceptive sensitivity. Am. J. Hum. Biol., 2011. © 2010 Wiley-Liss, Inc.