If you read some of the popular articles on meditation these days, you might get the idea that mindfulness is a cure for everything, from alleviating stress and anxiety to improving academic and athletic performance.
Now Assistant Professor of Neuroscience and Psychology Erika Nyhus and her student assistants are looking into whether memory improvement can be added to meditation’s long list of benefits. Meditation is the practice of becoming aware of one’s endless stream of thoughts and feelings, and then letting them pass without attaching weight to them. The activity trains people to disengage with distractions, so Nyhus wondered if it could also strengthen focus and help with information retention.
Nyhus’s research project is focusing specifically on source memory, which is how we contextualize our memories. For instance, source memory places any new information we learn in the context in which we first encountered it — say in a classroom or while watching a documentary. “It’s a harder kind of memory” than simply recognizing a familiar person, place, or story, Nyhus said, and people with memory deficits struggle in particular with it.
This summer, Nyhus is working with Isabella Vakkur ’20 to analyze the results of a study conducted in the 2015-2016 academic year with another student researcher. For the experiment, forty students with no meditation experience were recruited and the split into two groups of twenty. The control group did not meditate. The other group participated in a four-week course led by a meditation expert, and were asked to meditate on their own for twenty minutes a day.
This video demonstrates one of the memory tests Erika Nyhus’s lab uses
Students in both groups took two memory tests, one at the beginning of the study and one at the end. While they performed the exam, they were connected to an electroencephalogram (EEG) to capture the electrical brain activity between the hippocampus and prefrontal cortex, the two brain regions associated with source memory.
“To have effective source memory, you have to have good communication between the hippocampus and prefrontal cortex,” Vakkur explained. This summer, she has a Kufe Family Research Fellowship from Bowdoin to support her research job. She is one of nearly 300 students who have fellowships to pursue research projects or internships this summer.
In the first half of the test, the “encoding stage,” the student subjects were presented with 204 words, all simple adjectives, such as dirty, happy, and sad. For half the words, they were asked to associate the adjectives with a physical place, such as dirty kitchen sink. For the other half, they were instructed to think of the meaning of the word and how pleasant it was, even when the word had negative connotations, such as “dirty.”
Twenty minutes later, they were shown the words again, plus additional words, and asked to recall whether they had associated these words with place or pleasantness, or whether the words were new. These exercises offered a sense of how well the subjects were “sourcing” their memories of the words, or remembering the context in which they encountered them earlier.
Based on preliminary behavioral results from the source-memory test alone, the meditation group showed improvement in source memory from pre-test to post-test, but the control group did not. Vakkur is currently analyzing the EEG data to see whether there were, in addition, any changes in the subjects’ neural oscillations, which is how the hippocampus and prefrontal cortex send signals back and forth. “We hypothesized that the meditation group would show increased theta oscillations, as well, compared to the control group, and this increased theta power in meditators would be associated with improved memory retrieval,” Vakkur said.
It is important to their research that she and Nyhus back up the behavioral changes they’ve observed with neurological data, Vakkur said. “We’re interested in pinpointing the reason why we’re seeing these differences,” she explained. “It is one thing to see the scores improve, that they’re more accurate in labeling the words in the post-test, but we’re also interested in seeing why that’s happening.”
Vakkur, who is majoring in neuroscience and education and minoring in Chinese, said she’s appreciated the chance to be involved in research with real-world data, and has had the opportunity to explore a potential career path before committing to a graduate program. “I have friends at much larger research universities who don’t have access to research opportunities,” she said. “It’s really cool that we have this kind of one-on-one, hands-on research [with a professor], whereas at other places you wouldn’t get that until you’re a graduate student.”