Saturday, November 21, 2009

Listen to Music While Studying & Napping

Continuing on the theme of neuroscience and cognitive psychology researchers trying to understand better the function of sleep and dreaming, I've just read another really interesting article in the New York Times (I have an email alert set up for articles containing the term "brain").  The article, "Sounds During Sleep Aid Memory, Study Finds", reports on a study by Rudoy et. al. at Northwestern University that was recently published in the journal Science.  The findings suggest that individual memories can be improved when subjects hear sounds associated with those memories during a nap.

The memory task used in this study involved teaching subjects the correct location of 50 different icons on a computer screen.  Icons - small pictures of a cat or a tea kettle - were associated with relevant sounds (for example, a "meow" sound was played when the picture of the cat was on the screen).  The subjects then took a nap (less than 90 minutes of sleep), during which they were monitored via EEG to track their sleep stage.  During the nap, some subjects heard only white noise, while some other subjects were (unknowingly) exposed, during "slow-wave" sleep, to 25 of the sounds they'd heard during the picture location learning task.  After the nap, subjects were tested for their ability to place icons on the screen.

Subjects who, during their nap, had heard the sounds associated with the icons performed significantly better in the memory task than subjects who heard only white noise during the nap.  EEG patterns were measured between the two groups, and confirmed that there was a significant difference between the electrical activity of their brains.  Though not exhaustive, the researchers performed a variety of control experiments to determine whether or not the sounds played during slow-wave sleep were the causal factor in the improved performance of the subjects who heard them, and it seems reasonable to infer that they were.

I would like to see some continued research on the importance of icon-sound relevance relative to task performance post-nap.  In other words, would performance on the task be as improved if subjects had heard an "irrelevant" sound for each icon - say, a car horn honking when the icon of the cat was displayed?  Of course, it would also be great to see further research on different types of memory and learning tasks and potential improvements in performance by associating sensory experiences (sound, smells) during the learning process and during sleep following that learning experience.  I am also curious about the utility of listening to music while studying, and then listening to that same music while napping.  In the mean-time, so long as the music we choose doesn't distract from learning or from sleep, it would seem reasonable to suggest that memory task performance may increase as a result.

Monday, November 16, 2009

Dream Work

A recent article in the New York Times suggests that dreams are the phenomenological result of the brain exercising itself in preparation for its next waking state.  This idea of dreaming as a "protoconscious state", proposed by Dr. Hobson, a psychiatrist at Harvard University who focuses on studying sleep, adds to the body of literature that frames the brain as an organ that does work.  Much like muscles need exercise to function well, so, apparently, does the brain.  This view, in my opinion, supports similar findings that the brain, again like muscle, requires time after exertion to return to its resting state.  Finding an educational application for this view of the brain's need for exercise to be highly functional is fairly straight-forward: we should introduce new ideas and concepts over time, in ways that the student finds engaging and authentic, so that the brain will have an opportunity to practice its work with this new material during its exercise time.

Friday, August 21, 2009

Cognitive Recovery Time

Researchers at the University of Cambridge have recently published findings in PLoS One that demonstrate the brain's need for a period of "down-time" after a challenging cognitive task in order to return to it's resting state. Barnes and colleagues continuously monitored their subjects' brain activity using fMRI, first having the subject relax for a bit more than 9 minutes, then having the subject perform a cognitive task for 9 minutes, and finally having the subject relax for almost 19 minutes. The cognitive task employed in this experiment was the widely used "n-back" memory game, in which subjects are shown two co-varying stimuli (generally a set of numbers that appear in different locations in a grid) and are challenged to respond correctly when the set of stimuli is a repeat of the set presented "n" times ago. In the version of "n-back" used here, the numbers ranged from 1 to 4 and appeared in a 4-quadrant grid; "n" was either 1 or 2 for different subjects.

Barnes et. al. found that the brain, like the heart, does not simply return to it's resting state immediately following activity. In this experimental design, the brain took approximately 6 minutes to return to its resting state following the task; although there was no statistically significant difference in recovery times between the n=1 and n=2 subjects, the data did indicate that the brain took more time to recover when the cognitive task was more demanding. As the researchers point out in the final paragraph of the discussion, these findings help to clarify further research questions, including testing the performance of subjects engaging in a new cognitively demanding task following a previous task, but before the brain returns to its resting state. For those of us involved in education as classroom teachers or as administrators in charge of the daily schedule of classes for students, this line of research should prompt us to reflect on how we structure the use of time within the classroom, as well as how much time we afford students to return to their resting state in between classes.

Barnes A,
Bullmore ET, Suckling J, 2009 Endogenous Human Brain Dynamics Recover Slowly Following Cognitive Effort. PLoS ONE 4(8): e6626.doi:10.1371/journal.pone.0006626

Monday, August 3, 2009

Keeping Adult Brains in Mind for Professional Development Success

David Sousa's "Brain-Friendly Learning for Teachers" from the June 2009 issue of ASCD's "Educational Leadership" serves as a good source of information for improved professional development activities. Sousa's premise is that planning and implementing ongoing professional development with adult brain research in mind will make these experiences more likely to be successful. Adults, Sousa argues (anecdotally), are most powerfully motivated to learn when the experience seems likely to increase their ability to be effective in their work. This is a major take-home point for professional development in education, which, in my experience, is often done in large groups and is rarely differentiated. Although there are certainly aspects of our roles as teachers that are shared no matter what the subject area, it's important to keep in mind (particularly at the high school level) that educators are passionate about the subject(s) they teach, and that methods for effective teaching can vary significantly across subject areas. With those differences in mind, good professional development should incorporate small group "break-out sessions" in conjunction with large group presentations and discussions, so that the nuances of subject-specific teaching can be addressed and participants will be more likely to feel that the experience is going to make them more effective in their teaching.

Sousa's subsequent suggestions break down into four influences on adult learning; though these factors influence learning at all levels, Sousa suggests that adults are affected by them more powerfully given their advanced development relative to adolescents and children. The four factors are: emotions, feedback, past experiences, and meaning. While my own experiences of "sit and get" professional development have done a fairly good job of bringing in prior experiences and presenting topics in a meaningful way, a consistent critique I've had (and heard from many others) is that it's not realistic - or good teaching practice - to expect that we'll understand new information when it's presented only once, let alone without the time to really "digest" or get feedback on our attempts at implementation. When expectations are unrealistic and when the experience is so homogenized as to be of limited utility, negative emotions can build and interfere with the learning experience. However, an individualized professional development experience that will receive ongoing attention is likely to induce positive emotions in participants, thereby increasing the likelihood that good learning will take place that day and beyond.