By Fenying Zang
Older people often respond less consistently when making decisions. But does a similar behavioural pattern occur in other species, and what happens to the activity of individual neurons as the brain ages? Researchers at Leiden University, working with collaborators from the International Brain Laboratory (IBL) and University of California, Los Angeles, analysed the activity of more than 18,000 neurons in mice spanning early adulthood to old age. They found that older mice performed slightly worse and had more variable response times in a visual decision-making task. At the neural level, ageing was associated with higher firing rates across many recorded regions and greater variability after a visual stimulus appeared—but the patterns depended on the brain region and the time at which neural activity was measured.













