Map the Brain–Not Just Neurons

In any major mapping expedition shouldn’t the first priority be to survey the uncharted regions?  In mapping the brain, that would be charting the neglected half–glia.

The Brain Mapping Initiative announced by President Barack Obama earlier this year seeks to map and monitor the function of neural connections in the entire brain of experimental animals, and eventually in the human cerebral cortex. Several researchers have raised doubts about the project, cautioning that mapping the brain is a far more complex endeavor than mapping the human genome, and its usefulness more uncertain.

I believe that exploring neural networks and developing new techniques to do so are important goals that should be supported vigorously. But simply scaling up current efforts to chart neural connections is unlikely to deliver the promised benefits: an understanding of how the brain produces perception, memories and consciousness, or treatments for diseases such as epilepsy, depression and schizophrenia.

A major stumbling block is the project’s failure to consider that while the human brain contains approximately 100 billion neurons, it contains billions more non-electric brain cells called glia. These reside outside the neuronal ‘connectome’and operate beyond the reach of tools designed to probe electrical signaling in neurons. Dismissed as connective tissuewhen they were first described in the mid-1800s, glia have long been neglected in the quest to understand electrical signaling in neurons.

Recent research is revealing that glia can sense neuronal activity and control it. Glia operate in diverse mental processes, for instance, in the formation of memories; are central in brain injury and disease; and even the root of various disorders, such as schizophrenia and Alzheimer’s, previously presumed to be exclusively neuronal.

Our understanding of one half of the brain (the part comprised of astrocytes, oligodendrocytes and microglia) lags a century behind our knowledge of neurons. I believe that answers to questions about the brain and public support for a large-scale study are more likely to come from expanding the search into this unknown territory.

To read the full article in this week’s Nature, please see:

For additional information from the World Science Festival on this topic see this article on the Brain Mapping Salon Held at the WSF.  It featured many of the architects of the proposal in a panel discussion of its scope and objectives:

For some videos of the event see:


This entry was posted in by Douglas Fields, Neuroanatomy, Neuroeducation, Policymakers, Press and tagged , , , , , ,
The Society for Neuroscience and its partners are not responsible for the opinions and information posted on this site by others.
Douglas Fields

About Douglas Fields

R. Douglas Fields is Chief of the Nervous System Development and Plasticity Section at the National Institutes of Health, NICHD, in Bethesda, Maryland, and author of the new book about sudden anger and aggression “Why We Snap,” published by Dutton, and a popular book about glia “The Other Brain” published by Simon and Schuster. Dr. Fields is a developmental neurobiologist with a long-standing interest in brain development and plasticity, neuron-glia interactions, and the cellular mechanism of memory. He received degrees from UC Berkeley, San Jose State University, and UC San Diego. After postdoctoral fellowships at Stanford and Yale Universities he joined the NIH in 1987. Dr. Fields also enjoys writing about neuroscience for the general public. In addition to serving on editorial boards of several neuroscience journals, he serves as scientific advisor for Odyssey and Scientific American Mind magazines. He has written for Outside Magazine, The Washington Post Magazine, Scientific American and Scientific American Mind, and he publishes regularly for The Huffington Post, Psychology Today, and Scientific American on-line. Outside the lab he enjoys building guitars and rock climbing.

The opinions stated in the blog are the personal opinion of the author and not those of the federal government.

Leave a Comment