Scientists have figured out how a pigeon’s brain figures out where it is, and how to get home – it’s an internal GPS, or global positioning system, that uses the Earth’s magnetic fields to navigate – and it’s probably better than the one you’ve got in your SUV.
According to researchers Le-Qing Wu and David Dickman, neurons in a pigeon’s brain use the Earth’s magnetic field to orient themselves. No mean feat, but how did the scientists figure this out? They took seven pigeons, placed them in a completely dark room, and used a device to cancel Earth’s natural magnetic field. Then, they generated an artificial magnetic field, and measured the brain activity of the birds. As they changed the magnetic field, they found neurons in the bird’s brains firing in response.
Decoded Science had the opportunity to ask David Dickman, PhD, of Baylor College of Medicine a few questions about this study. We asked Dr. Dickman about the inspiration for his study, and he responded as follows:
We work on the inner ear and it’s function. A previous study (Harada et al., Acta Otol, 2001) suggested that the inner ear may be involved in magnetoreception and we followed their lead.
Neuroscience and Magnetic Fields: Future Studies
Will this research lead to additional studies? According to Dr. Dickman, “We have opened a completely new area of research in neuroscience. How does the brain use magnetic field information for positional, heading, and navigation functions? Hundreds of questions need to be answered. Most important, how do all animals know where they are, where to go, how to get there, and what happens when brain disease or trauma impairs those functions. We now have a model to examine those questions.”
Changing a Bird’s Sense of Direction
If the scientists were able to stimulate the birds’ neurons through an artificial magnetic field, we wondered if it would be possible to manipulate their sense of direction with that field? (Reprogramming the GPS, so to speak) We asked Dr. Dickman, and he agreed that it was, “Absolutely” possible.
Additional research on this topic may provide more details, but the most surprising result may never be surpassed – the fact that a pigeon’s brain cells are sophisticated enough to act as a GPS system, using the Earth’s magnetic field to find the right direction! According to Dr. Dickman, “these brain cells have all the information needed to determine Earth latitude and directional heading (like a compass).”
Wu, L.-Q, Dickman, J. D. Neural Correlates of a Magnetic Sense. (2012). Science Express. Accessed April 26, 2012.