Acting out a word or phrase may help people keep memory of it — a phenomenon called the enactment effect — and this also may hold true for those with poor motor control due to Parkinson’s disease, according to a review study.
“Our meta-analysis found that even Parkinson’s disease patients who struggle to execute actions can have their memory improved by enactment, possibly because their planning abilities remain intact,” Brady Roberts, said in a press release. Roberts is the study’s first author and a PhD candidate in cognitive neuroscience at the University of Waterloo, in Canada.
The review study, “The enactment effect: A systematic review and meta-analysis of behavioral, neuroimaging, and patient studies,” was published in the Psychological Bulletin.
Parkinson’s is a neurodegenerative disease that occurs when there is a loss of nerve cells in the substantia nigra, a region of the brain that helps control body movements.
This causes a range of motor symptoms, from resting tremor to muscle rigidity and slowness of movement. But there also are non-motor symptoms, such as mood changes and cognitive deficits, which can include memory problems.
“When you stop and think about it, memory permeates throughout most other cognitive functions,” said Roberts. “I’ve seen the real need for memory research in my own grandmother who is starting to demonstrate memory deterioration that comes with aging.”
“The enactment effect is the phenomenon that physically performing an action represented by a word or phrase (e.g., clap, clap your hands) results in better memory than does simply reading it,” the researchers wrote.
To get a general view of how the enactment effect works, Roberts systematically reviewed studies on the phenomenon that were published in the past 60 years. Roberts worked with his supervisors Myra Fernandes, PhD, and Colin MacLeod, PhD, both professors in the psychology department at the University of Waterloo.
“Our objective was to contextualize the enactment effect as a powerful memory strategy, and we found it can benefit people across a range of demographics and cognitive abilities,” Roberts said.
A total of 183 studies were included in the meta-analysis. Most (145 studies, 79.3%) were behavioral studies, seven (3.8%) were neuroimaging studies, and 31 (16.9%) were studies of people with neurological conditions.
The team analyzed how different strategies — physical actions, reading words or phrases, watching another person perform actions, and imagining performing actions — change how much information can be stored and retained.
Pooled data from the behavioral studies showed that enactment had a large effect on memory performance. However, its effect varied depending on the design of the study and the strategy used for comparison.
Neuroimaging studies indicated that enactment mainly turns on two regions of the brain: the motor cortex, which regulates body movements, and the inferior parietal lobule, which helps people imagine objects, pay attention, and work their language.
Pooled results from studies on neurologic disease patients showed that even those with poor motor control due to Parkinson’s, or patients with memory problems due to Alzheimer’s, another neurodegenerative disease, benefited from the enactment effect.
“Enactment was found to be a reliable and effective mnemonic tool for both neurotypical [neurologically typical] and patient populations,” the team wrote.
The findings also highlighted “two components accounting for the memory benefit from enactment: a primary mental contribution relating to planning the action and a secondary physical contribution of the action itself,” they added.
“Enactment is a great example of rich multi-sensory encoding,” Roberts said.
The findings establish a foundation for designing strategies to improve memory for all.
“Given the potency and ease-of-use of enactment in real-world settings, including improving memory in patients with Alzheimer’s disease, it’s an important area of research worthy of further exploration,” Roberts said.