Decision-making far more widely distributed across the brain than previously thought, study finds
Researchers have completed the first-ever activity map of a mammalian brain in a groundbreaking duo of studies, and it has rewritten scientists’ understanding of how decisions are made.
The project, involving a dozen labs and data from over 600,000 individual mouse brain cells, covered areas representing over 95% of the brain. Findings from the research, published in two papers in the journal Nature, suggest that decision-making involves far more of the brain than previously thought.
The mammoth project was led by the International Brain Laboratory (IBL), a collaboration of experimental and theoretical neuroscientists from across Europe and the U.S. These scientists were united by a familiar, nagging feeling.
“We had a problem with the way science was done,” said Matteo Carandini, a neuroscientist at University College London and a core member of the IBL.
In previous studies of the brain, many separate labs set out to answer big questions about the organ, exploring how brain activity relates to behavior, for instance. However, each lab studied this question in different mice’s brains, and performed slightly different behavioral tasks with each set of rodents. Once you added in uncertainties around how each research group defined distinct regions within the brain, these inconsistencies muddied the results.
“We wouldn’t know whether we actually agree or disagree, because so many things were different,” Carandini told Live Science.
So the IBL came together to design a single, robust, standardized experiment on a scale that no individual lab could tackle alone. They then paired this megatest with precision brain measuring tools and preset analysis methods to make the results as reproducible as possible. The aim of the experiment would be to overcome an enduring obstacle in the field.
“One of the longest-standing challenges in neuroscience is to decipher how variation in neural systems — both structural and functional — maps onto variation in behavior,” Federico Turkheimer, a neuroscientist at King’s College London who was not involved in the study, said in a statement to the U.K. Science Media Centre. [Continue reading…]