In groundbreaking study, researchers publish brain map showing how decisions are made

The data, gathered from 139 mice, encompass activity from more than 600,000 neurons in 279 areas of the brain about 95% of the brain in a mouse. This map is the first to provide a complete picture of what happens across the brain as a decision is made.

“They have created the largest dataset anyone has ever imagined at this scale,” said Dr. Paul W. Glimcher, chair of the department of neuroscience and physiology and director of the Neuroscience Institute at New York University’s Grossman School of Medicine, of the researchers.

In the field of neuroscience, “this is going to go down in history as a major event,” Glimcher, who was not involved in the new research, told CNN.

To construct the map, researchers first created a standardized procedure to be shared across laboratories and then tracked neural activity in mice as the rodents responded to visual prompts, integrating all the data gathered by each lab. Seven years in the making and presented in two studies, the findings were published on September 3 in the journal Nature.

“There are basically two big results, which is why we have two papers,” said Alexandre Pouget, a full professor in basic neuroscience at the University of Geneva. One study outlined the widespread distribution of electrical activity related to decision-making. The other used the data to evaluate how expectations shape choices. Pouget is a coauthor of the first study and senior author of the second.

“We started from scratch,” he told CNN. “Nobody had ever attempted to do something like this before.”