The news: Researchers from Google and Janelia Research Campus in Virginia have unveiled the biggest high-resolution map of brain connectivity yet, known as a connectome. It shows a diagram of a fruit fly’s brain, containing 25,000 neurons and the 20 million connections between them. What does it show?: The map shows a region of the fly’s brain that is about 250 micrometers across, equivalent to the thickness of two strands of hair. The mapped area accounts for about a third of the fly’s total brain, and it contains regions associated with memory and navigation.
The context: It’s a landmark for neuroscientists, who would love to be able to connect areas of the brain to specific behaviors. But not all neuroscientists are convinced that brain mapping in this way (connectomics, as it's known) is the best use of resources.
What about humans?: We’re still a very long way off creating a complete connectome of the human brain. Fruit fly’s brains contain nearly 100,000 neurons. Human brains have about 86 billion. Read the full story.