Scientists have developed the most detailed map of the fruit fly brain to date, revealing nearly 140,000 neurons and 54.5 million synapses. This achievement comes after more than four years of work by researchers, led by neuroscientists Mala Murthy and Sebastian Seung of Princeton University. The map, known as the connectome, represents the most complete diagram of the brain for any organism.
This detailed project uses electron microscope images to reconstruct a fly’s brain. AI-assisted tools helped with the data collection, although many parts required manual review. The research team, along with volunteers, made more than three million manual edits to ensure accuracy. These efforts revealed 8,453 types of neurons, of which 4,581 were newly discovered.
Surprising discoveries in neural connections
During the study, the researchers discovered surprising details about how different neurons are connected to each other. They found that neurons typically involved in sensory processing, such as visual circuits, often connect with neurons responsible for other senses, such as hearing and touch. This discovery highlighted the complex integration of sensory information within the brain.
An insight into fruit fly behavior
The collected data has already been used to simulate the behavior of the wine fly in virtual models. In one experiment, the simulation showed that neurons responsible for detecting sweet or bitter taste activate motor neurons that control the fly’s proboscis. When tested on real flies, the virtual model was more than 90% accurate in predicting neuronal responses and behavior.
Future research potential
Although the map is based on a single female fruit fly, it provides significant insight into the function and structure of the brain. The researchers plan to expand the project to include male flies and study behaviors such as singing. Despite the progress, researchers note that much remains to be understood about the chemical and electrical communication between neurons.
