New Evidence for Sleep Learning

It’s known that our brains can review what we’ve learned during the day increasing the chances of retention. A recent study also suggested that the brain retains best what we most desire to learn.

However, it’s never been clear that something new going on during sleep can be accessed by our brains. Now, a team of neuroscientists played complex sounds to people while they were sleeping, and afterward the sleepers could recognize those sounds. Such learning has been a debated topic for years according to one author of the study1.

Researchers in the 1950s dismantled claims that sleepers can learn facts, so you can’t learn a new language or concrete subject matter by playing DVDs while you sleep. Don’t bother putting a book under your pillow. However, it seems that the sleeping brain can take in some sensory information and store it in the subconscious. This is only possible during REM sleep according to the team. In a 2014 study, Israeli neuroscientists had 66 people smell cigarette smoke coupled with foul odors while they were asleep. The test subjects avoided smoking for two weeks after the experiment.

Maybe we can learn to break bad habits during sleep. Hmm, if there are smells associated with projects we want to complete, we could combine those smells with the smell of fresh-baked bread or lilacs while we doze the night away.

I assume—correctly—that the sleeping brain cannot tune into visual cues. I wonder if touch has been studied. Might wake us up and I can’t think of a useful experiment or application.

It seems to me the practical implications are minimal, but I find the fact that our brains are not completely out of it during sleep is fascinating and adds to our understanding of how that 3 pounds of matter works.

1, Thomas Andrillon, a neuroscientist at PSL Research University in Paris


PS: Still in Eastern Europe and the farewell dinner is on our anniversary.

Can a cell have an idea?

This brain has bright ideas

That’s the idea that fascinated  Marian Diamond as a young girl,  propelling her to a career on brain research and becoming a woman known for toting a pickled brain around in a flowered hat box . As the first female graduate student in the Department of Anatomy at UC Berkeley, she achieved her PhD and became the first woman science instructor at Cornell University. Continuing her achievement of firsts, she with two colleagues conducted experiments on lab rats, providing evidence that the brain was not genetically fixed as conventional wisdom long held. Instead, a rich environment expands the brain’s capacity. Today, brain plasticity is a fertile area of research, but during her first conference talk her results were denigrated by the male audience.

Not satisfied with conducting research with rat brains, she launched experiments in areas of the world lacking quality educational resources. Her success not only established environmental impact on the human brain, it served the humanitarian purpose of vastly improving education. Later she established that brains of the elderly also benefit from stimulation. Motivated by her love for her husband she found evidence that love increases longevity as another of her significant achievements.

She requested and to her excitement received slices of Einstein’s normal-sized brain and became the first to delve into the secrets of his remarkable mind, discovering, as in rat brains, a higher ratio of glial cells to neurons. It had been thought that the only role of glial cells involved housekeeping, namely supplying nutrients and destroying dead cells. Electrical signals between neurons conveyed by synapses accounted for thinking, While glia cannot produce electrical signals, recent research found they produce chemical signals and do play a role in our thought processes. Score another profound advancement  to our heroine. The purist in me needs to point out that a single cell probably cannot have an idea. It takes a village of well-connected cells, but Dr. Diamond’s point remains. Single cells, electricity, and chemistry amazingly produce ideas.

Marian Diamond raised four children and taught more than 60,000 adoring students over her academic career. An attractive, well-dressed woman with a sense of humor, she threw a piece of chalk at the end of her lectures and took the lucky catcher out to lunch. She combatted sexual discrimination by ignoring it and wildly succeeding. I could identify with her retirement in her mid-80s despite her continuing vitality, echoing my thought that it is best to go before people sigh with relief at your leaving. The PBS documentary on her life, My Love Affair With The Brain is an inspiration and can be seen online. In writing this I discovered there is an entire web series on her life. I’m signing up.

My love affair with the brain
My love affair with the brain—all web episodes 
Marian Diamond by Wikipedia
Conversation with Marian Diamond
Brain Facts