Need to remember some important facts for that big presentation at work? Clench your right hand while preparing to remember. When giving that talk, ball up your left hand and you’ll call to mind those details, no problem.
That’s the finding from a new study authored by Ruth Propper, an associate professor and director of the cerebral lateralization laboratory at Montclair State University. Propper has long been intrigued by how body movements impact how the brain works. While most people realize that the brain influences the body (the brain tells your arm there is an itch, and you feel it), less is understood about how the body sways the brain.
Past research suggests that clenching our hands can evoke emotions. When people ball up their right hands, for example, the left sides of their brains become more active, causing what’s known as “approach emotions,” feelings such as happiness or excitement. By squeezing the left hand, people engage the right side of the brain, which controls “withdrawal emotions” such as introversion, fear, or anxiety. (It probably seems like these might be less useful, but they come in handy in dangerous situations.)
Propper theorized that if clenching hands impacted feelings, these gestures might influence the brain in other ways.
To learn how hand clenching influenced memory and recall, she asked 51 right- handed subjects to memorize 72 words and randomly assigned each person to one of five hand-clenching groups or a control group that did nothing. Only righties were included because lefties exhibit better episodic memory overall so they’d have an unfair advantage. She found the perfect combination for better memory and recall occurs when a subject clenches his right hand while memorizing and balls up his left hand while trying to recall the memory.
“It is interesting to compare to not clenching at all. It’s almost 15 percent better [to clench right then left] than sitting there,” she says.
While a 15 percent improvement is on the edge of being statistically significant, Propper notes 15 percent can be the difference between an A and a C on test.
Propper admits that more research needs to be conducted on how bodily movements enhance brain function, but she recommends that people try squeezing their hands to aid with memory.
“I would say that it would be worth trying,” Propper says. Take parking your car in the parking lot. “(A)s you park you can clench your right hand and when you are trying to find it, clench your left hand.”
The paper appears in PLoS One.