BOB HIRSHON (host):
Refreshing your memory…I’m Bob Hirshon and this is Science Update.
If a sound or other stimulus goes on long enough, we begin to ignore it—a process called habituation. Cognitive psychologist Alejandro Lleras of the University of Illinois, Urbana-Champaign, wanted to know if something similar happens when we try to focus on tedious tasks.
ALEJANDRO LLERAS (University of Illinois, Urbana-Champaign):
Why it is that after 30 or 40 minutes, people’s performance starts to decrease, they start to get bad at what they’re doing?
He and his colleagues had volunteers memorize numbers and then recall them over the course of about an hour. Most people’s recall got worse over time, but those who were allowed to take brief breaks refreshed their focus and performed better. Lleras says this makes sense, because our brains have evolved to notice new things such as predators, and ignore routine things that pose no threat to our survival. I’m Bob Hirshon, for AAAS, the science society.