Wednesday, December 3, 2014

3-D compass in Egyptian fruit bat's brain

Egyptian fruit bat Rousettus aegyptiacusimage Wikimedia

Ruth Schuster reported 03/12/2014 in Haaretz about a fascinating brain research project going on in Weizmann Institute:

Israeli scientists have finally proved the existence of a three-dimensional compass in mammalian brains, with the help of the humble fruit bat.

Grad student Arseny Finkelstein and team demonstrated that the brain of the Egyptian fruit bat has special neurons that can tell which way its head is pointing. They could be key to the bat navigating in space, says the team in a study published today in Nature.

Vertigo such as that experienced by fighter pilots happens when this system goes haywire, their study suggests.

Navigation relies on spatial memory: past experience of different locations, they explain. That spatial memory is formed in a primitive brain structure in the hippocampus.

In the mammalian hippocampus, there are three types of brain cells key to navigation: “place” and “grid” cells, which like a biological GPS system, enable animals to keep track of their position - and “head-direction” cells. Those are the ones that act like a compass, responding when said beast turns its head.

Much work had been done on place and grid cells but practically none on the head-direction one. To change that, the researchers enlisted fruit bats with micro-electrodes implanted in their brains, to monitor their neuronal activity, and tracking devices that could tell when the bats moved their little heads.

Read the entire Haaretz science article.


Wildscreen ARKive has photos, videos and facts about the charming Egyptian fruit bat Rousettus aegyptiacus

Nature article preview  Arseny Finkelstein, Dori Derdikman, Alon Rubin, Jakob N. Foerster, Liora Las & Nachum Ulanovsky Three-dimensional head-direction coding in the bat brain