Nov. 29, 2016 "Use it or lose it": Today I found this article by Maura R. O'Connor in the Edmonton Journal:
A few years ago on a visit to the high desert of northern New Mexico I punched the name of a local hot spring into my phone’s navigation app and set off in my car, following the directions down a twisty dirt track that ended 10 metres from the edge of a cliff. Some 30 metres below was the Rio Grande and, I assumed, the hot spring. The directions would have been perfect if cars could fly.
Stories of being led astray by satellite navigation systems such as GPS are increasingly common as digital devices become ubiquitous in our daily lives. Some tales are simply ridiculous, others have ended in death.
While many of the reports we hear about tragedy on the roads involving technology have to do with drivers distracted by using their devices while at the wheel, research has found our reliance on technology for tasks like navigation may have far wider consequences, in effect causing some of the same problems in the brain that those diagnosed with dementia experience.
Not only are many distracted at the wheel, their brains may be less resilient as well.
“If people stop using their brains and totally devote themselves to their hand-held devices to find their way around the world, that could have a negative effect on getting around, and spillover effects on other things like memory,” Lynn Nadel, a neuroscientist at the University of Arizona, said.
GPS solves a problem unique to the human species: we lack a biological compass that can orient us in space.
Nearly all other organisms known to science can navigate long distances with astonishing precision, while we’re prone to becoming lost.
Humans have adapted by using observation, memory and invention to get around this problem and navigate.
Nadel and fellow researcher John O’Keefe published a landmark book in 1978 exploring the role of the hippocampus, a simple sea-horse-shaped structure of grey matter deep in the brain. They argued that cells in the hippocampus build blocks of cognitive maps, the internal representation of space that allows both rats and humans to recall routes and relationships between landmarks and orient in space.
Building on their research, scientists have learned more about the hippocampus and its role in helping us map complex spaces in our minds. They’ve also learned the hippocampus is the basis of our episodic memory, giving us the ability to recall events about our lives.
When you remember something from your past, that’s your hippocampus in action. In the early 1990s, one of the scientists studying this relationship between memory and space was Véronique Bohbot, a student of Nadel’s in Arizona. Bohbot, now a Montreal-based neuroscientist at the Douglas Mental Health University Institute and an associate professor at McGill University, became interested in the possibility that people use different structures in the brain for different strategies of navigation and began to design studies focused on one called the caudate nucleus.
The caudate nucleus operates differently than the hippocampus. Whereas the latter is involved in creating cognitive maps, the caudate nucleus is responsible for a “stimulus-response strategy.” According to Bohbot, this allows the brain to learn a series of directional cues such as “turn right” and “turn left” and create a habit of them.
Effectively, we go on autopilot. The more we use autopilot, Bohbot found, the less we rely on our hippocampus, which can shrink its grey matter volume. Several studies have found that reduced grey matter in the hippocampus is associated with cognitive deficits of aging like memory impairment, and increases the risk of atrophy, dementia, and Alzheimer’s disease.
Bohbot said she believes many of the mental impairments associated with aging may be connected to changes in how we use our brains over our lives, from navigating and exploring space as children to increasingly relying on familiar routes as adults.
Over the course of adulthood, Bohbot and her fellow researchers believe, navigation behaviour becomes more automatic, with less reliance on the hippocampus. This underuse can lead to a decrease of grey matter volume.
The caudate nucleus is also located in the striatum, a brain area involved in addiction. Bohbot wanted to find out whether people who rely on a stimulus-response strategy to navigate might show any difference in addiction behaviour from those who relied on spatial strategies.
She conducted a study of 55 young adults and discovered that those who use a stimulus-response to complete a virtual maze had double the amount of lifetime alcohol consumption, as well as more use of cigarettes and marijuana.
When we turn on the GPS on our phones and follow turn-by-turn directions, we are using a classic stimulus-response strategy. Our caudate nucleus is activated and we bypass the creation of cognitive maps.
Although there are no studies yet specifically testing whether using GPS when we drive or navigate can cause cognitive impairments, the risks of letting our hippocampus go unused are considerable. “There is a use it or lose it thing about the brain,” said Nadel, who cited studies showing that London taxi drivers, who are required to memorize vast amounts of spatial information and create new routes on a daily basis to zip passengers around the British capital, have more grey matter in their hippocampus.
Bohbot says research so far is changing scientific understanding on how hippocampal volume relates to disease and aging. “People who have a shrunk hippocampus are at risk for PTSD, Alzheimer’s, schizophrenia, depression,” Bohbot explained.
“For a long time we thought the disease causes shrinkage in the hippocampus. But the shrunk hippocampus can be there before the disease.”
Forecasts predict that the number of turn-by-turn navigation app users will reach nearly 400 million in 2017, four times the number in 2011, according to the market research firm Berg Insight. With so many million people changing how they navigate, could this aspect of how we use digital devices on the move pose a public health threat?
There’s no evidence or studies to support this claim. What can be said is that frequent use of GPS might be compounding cognitive health declines.
Scientists already know that several common conditions of modern life — chronic stress, untreated depression, insomnia and alcohol abuse — have been shown to affect hippocampal volume.
Bohbot encourages individuals to use and create cognitive maps as much as possible in their daily lives.
This requires paying attention to one’s surroundings and landmarks, and inventing new routes and shortcuts to get to both familiar and novel destinations.
Turning off the GPS, at least now and then, is one way to keep those skills engaged. “In the past we may never have had to go on autopilot,” Bohbot said. “With GPS, you might have even less of a reason to pull out that cognitive map. The hippocampus may be lacking this requirement to work for decades when you only use it once in a while.”
Maura R. O’Connor is a fellow at MIT’s Knight Science Journalism Program and is currently working on a book about neuroscience and human relationships to space, time, and memory.
Her first book, Resurrection Science: Conservation, De-Extinction and the Precarious Future of Wild Things, was named one of Amazon’s Best Books of 2015. O’Connor has written for Slate, the New Yorker, and Harper’s. - See more at:
Dec. 19, 2016 "The upside of the aging brain": Today I found this article by Adriana Barton in the Globe and Mail:
New research suggests that while mental sharpness wanes with age, that reduced focus may enhance abstract thinking
This is part of a series on aging well.
Focus, focus, focus. This mantra for success is drilled into us from childhood all the way up to our working years. In older adults, however, there may be an upside to a wandering mind.
Mental distractions may help reinforce memory in adults 60 and older– but not younger adults, according to new research from the University of Toronto.
Moreover, while mental sharpness declines with age, reduced focus in older adults may enhance the kind of abstract thinking needed for problem solving and creative work.
Depending on the task at hand, “the ability to cast a wider attention net and process more information can sometimes be beneficial,” said Tarek Amer, a PhD candidate in psychology at the University of Toronto and lead author of a paper entitled, “Cognitive Control as a Double Edged Sword,” published in November in the journal Trends in Cognitive Sciences.
Amer and colleagues reached this conclusion after evaluating older adults and college students in a study at the Rotman Research Institute in Toronto. They gave participants a list of words to memorize. Then, in the next task, they asked them to press a button whenever they saw the same picture reappear on a screen. Words superimposed on the pictures were designed as distractions. Some were random, while others were among the list of words participants were supposed to remember. When participants did the word memory test for a second time, Amer said, older adults were more likely to remember them, “while our younger adults did not show this effect.”
College students may be better at ignoring distractions as they focus on a task, but older adults may be better at noticing patterns in the world around them, Amer explained.
For example, an older adult involved in a conversation might pick up on current road conditions from a TV across the room, whereas a younger adult might be paying closer attention to the conversation itself. Later, the older adult might make use of information from the distracting TV broadcast while planning a route home.
Geriatricians could focus on leveraging the strengths of the aging brain, instead of encouraging older adults to try brain-training exercises on a computer – the majority of which have failed to show benefit in daily life, Amer pointed out.
For example, a smartphone app or game designed for older adults could include useful information in the background, or as a ticker on the screen. Presenting information repeatedly, even in the form of distractions, “seems to be beneficial for older adults,” Amer said.
In healthy aging, as opposed to the cognitive changes in dementia, older adults show thinking patterns that allow them to make connections among pieces of information that are right in front of them, as well as information they have encountered in the past.
“The ability to form these broad associations might be involved in creative thinking,” Amer said. Creativity not only plays a role in art or music, he added, but also in activities such as experimenting with new ingredients in a recipe, or coming up with novel solutions to a social problem.
In general, older adults tend to have more focused attention in the morning and more abstract thinking later in the day, he said.
College students, on the other hand, tend to be less focused in the morning but reach their peak attention in late afternoon or evening.
For a writer in her 70s, late afternoon might be a good time to jot down ideas for a new book chapter.
She might want to save editing for the next morning, when her mind is more primed for focused, analytical tasks.
Although the research paper did not refer to art history, changes in thinking patterns later in life might explain why artists such as da Vinci , Michelangelo, Beethoven and Picasso produced their most groundbreaking works well after they turned 50.
More recently, R&B singer Bettye LaVette became a critics’ darling at 59. French sculptor Louise Bourgeois developed her monumental spiders in her late 80s. And nearly three decades after releasing his most popular album, I’m Your Man, at age 54, the late Leonard Cohen completed his last album, You Want It Darker, at 82. Clearly, the youthful brain and its laser focus are not the be-all and end-all.
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