Montclair State Professor's Research Helps Soldiers Get a Grip on Memory

Study explores how hand clenching can enhance memory

Release Date: April 25, 2013

Dr. Ruth E. Propper, associate professor of psychology at Montclair State University, wants to keep soldiers safe by sharpening their memories.

Her article, “Getting a Grip on Memory: Unilateral Hand Clenching Alters Episodic Recall,” published in the April 24, 2013 edition of PLOS ONE (http://DX.PLOS.ORG/10.1371/JOURNAL.PONE.0062474) examines how a technique as simple as hand clenching can result in improved recall of information.

In a study conducted at the University and funded by a Department of Defense (DOD) grant, Propper and co-authors, including Montclair State graduate students, Sean McGraw and Michael Weiss, tested five groups of participants who squeezed – or did not squeeze – rubber balls immediately before studying a list of words and immediately before recalling the words. “We tested the subjects’ recall of low frequency words in the English language such as aardvark and twilight,” says Propper.

“We report that 90 seconds of right hand clenching prior to studying information, followed by 90 seconds of left hand clenching prior to recall results in superior memory for information,” Propper explains. “The converse – left hand clenching followed by right hand clenching – impairs memory.”

This kind of hand clenching activates the left and right hemispheres of the brain. Right hand clenching activates the left hemisphere, which is involved in encoding information into memory; left hand clenching can facilitate the retrieval of information from the right hemisphere. 

In an earlier study that was also funded by her three-year DOD contract, Propper suggested that unilateral gaze could increase geographical memory. “It is possible that simple techniques designed to enhance cognition by changing how the brain is functioning at a given moment – such as unilateral hand clenching or eye gazing – could be easily adapted to military field situations to facilitate memory and improve performance,” she says. This could ultimately help keep soldiers safe in the field.

Her work could even help anyone wishing to remember where they put their keys or memorize a phone number. “It could be helpful, right before putting down the car keys, for example, if you clench your right hand. Right before trying to recall where you’d left them, you’d clench your left hand,” she says.



Suzanne Bronski
Director of Media Relations
(973) 655-4334
(917) 292-9554 (cell)

Meaghan Morin
Communications Assistant
(973) 655-4333