After providing all the funding for The Brain from Top to Bottom for over 10 years, the CIHR Institute of Neurosciences, Mental Health and Addiction informed us that because of budget cuts, they were going to be forced to stop sponsoring us as of March 31st, 2013.

We have approached a number of organizations, all of which have recognized the value of our work. But we have not managed to find the funding we need. We must therefore ask our readers for donations so that we can continue updating and adding new content to The Brain from Top to Bottom web site and blog.

Please, rest assured that we are doing our utmost to continue our mission of providing the general public with the best possible information about the brain and neuroscience in the original spirit of the Internet: the desire to share information free of charge and with no adverstising.

Whether your support is moral, financial, or both, thank you from the bottom of our hearts!

Bruno Dubuc, Patrick Robert, Denis Paquet, and Al Daigen

Tuesday, 17 March 2020
A Chair Doesn’t Have To Be Electric To Be Dangerous

Moving is good for your brain. We all know this instinctively, because of the way we just feel better after walking, dancing, playing soccer or engaging in other physical activity. But too often, we forget, because we have too much work to do, too many e-mails to answer, too many TV series to stream and so on. As a result, all too many of us end up spend all too many hours sitting every day. Scientists who study this issue use the term “sedentariness” to describe this pattern in which people remain seated and expend very little energy for long periods. And the scientists’ studies have shown that there is a meaningful distinction between how sedentary someone is and how much physical activity they engage in every day or week.

Many of us tend to think that if we go jogging twice per week, or get a lot of other exercise, we can spend the rest of our time working in front of our computers without incurring any of the risks associated with being sedentary, such as obesity, diabetes and cardiovascular disease. But that’s not entirely true, the specialists tell us (as does your back when you’ve spent several hours in your chair without getting up). Their research has shown that being sedentary and being physically inactive are two different things, both of which are bad. The worst case, of course, is someone who is sedentary and also does not get much exercise, and the the best case is someone who is not sedentary and also gets a lot of exercise. But in between there are the many people nowadays who engage in physical activity a few times per week but also spend a tremendous amount of time in a seated position. Recent studies have shown that staying seated for 8 hours per day inevitably has negative effects on your physical and mental health.

Inevitably, but with an interesting qualification, reported in a 2016 article published in The Lancet, entitled Does physical activity attenuate, or even eliminate, the detrimental association of sitting time with mortality? A harmonised meta-analysis of data from more than 1 million men and women. This meta-analysis found that exercise such as walking or cycling at a steady pace for 30 minutes was sufficient to offset the increased risk of mortality associated with spending 4 hours sitting. If you spend an 8-hour work day sitting, you would have to do about 60 minutes of moderately intense physical activity (activity that raises your heart rate) to realize the same compensatory effects. Interestingly, this meta-analysis found that the benefits were the same even if these 60 minutes of activity were divided into several periods over the day. Another interesting finding was that physical activity has less of a compensatory effect if you spend your sedentary time watching TV.

In 2016, a consortium of Canadian health institutions and organizations issued a set of recommendations for fighting sedentariness. They proposed a new approach that anyone can follow. It encourages any behaviour that interrupts prolonged periods of sitting and thus stimulates blood flow, the endocrine system and so on. The benefits begin with simply standing up, although they increase if you walk instead and even more if you run. For example, a 2015 study showed that two minutes per day of light activity, such as washing the dishes, could reduce the risk of death by 33% compared with people who remain completely seated every hour.

Knowing all this, the easiest decision to make to do your brain some good may not be to sign up for a boot camp at your local gym but simply to resolve to get up from your computer every once in a while and do something like stretch or take out the garbage, or hold your meetings with colleagues while walking with them in the park, or run your errands on foot or on your bike instead of in your car. Pretty soon, you’ll get into a sort of a “virtuous circle ”, because these activities will tire your body out enough that you’ll also fall asleep faster and sleep better at night (even more so if you can add, say, a half-hour of daily exercise that actually makes you work up a sweat). As a result, you’ll wake up better rested, so you’ll have more energy to move around more during the day, so you’ll sleep better at night, and so on.

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Friday, 28 February 2020
The multiple levels of organization of living things: more central than ever to cognitive science

This week I want to talk about a concept that is fundamental to an understanding not only of the human brain but also of the entire human adventure in general: the various levels of organization of living systems. This concept is central to the most influential current studies in theoretical biology, if one is to judge from the article “Answering Schrödinger’s question: A free-energy formulation”, by Maxwell Ramstead of McGill University’s Department of Psychiatry and his colleagues Paul Badcock and Karl Friston, published in March 2018 in the journal Physics of Life Reviews. While I will not delve here into the details of the free-energy principle that is central to all these studies, I will describe this article as the first attempt to explain the dynamics of cognitive systems at every scale on which they occur. In other words, these three authors attempt to consider every behaviour of living beings as the product of “nested systems of systems”. (more…)

From the Simple to the Complex, Memory and the Brain | No comments

Wednesday, 5 February 2020
Blood-glucose levels influence judges’ decisions less than we think

Science is based on empirical facts, such as data gathered in experiments. But it is also based on the interpretation of these facts, what they mean, what may have made them possible. (In scientific articles, the data—the facts—are presented in the “Results” section and interpreted in the “Discussion” section.) It should be no surprise that in any given field of science, some scientists may disagree with the way that their colleagues have interpreted certain results. Such disagreements arise in all scientific disciplines, especially in psychology, and especially when the data are very clear-cut or the correlations are very strong. And it’s just that kind of a case that I’d like to discuss in this post today (maybe in some future post, I will discuss the broader results-reproducibility crisis that has been shaking psychology for some years now). (more…)

From Thought to Language | No comments

Wednesday, 8 January 2020
The Glymphatic System: The Sewers of the Brain

As has been well established, the human brain consumes tremendous amounts of energy: about 20 to 25% of all the energy that the body uses, even though this organ accounts for only 2% of the body’’s total weight. As a result, the brain necessarily produces large amounts of waste—the equivalent of its own weight in waste every year! But this waste can be toxic to the brain itself. How the brain gets rid of this waste was long a mystery to scientists. Some thought that the brain might cleanse itself through passive diffusion of cerebrospinal fluid from the cerebral ventricles, but this seemed like a very slow waste-removal mechanism for such an active organ as the brain. It was not until 2012 that studies on mice showed that the brain has its own specific waste-removal mechanism that is faster and more efficient.. (more…)

From the Simple to the Complex | No comments

Monday, 25 November 2019
Three On-Line Atlases of the Human Brain

This week I want to tell you about three different on-line atlases of the human brain. All three will let you satisfy your curiosity by exploring the inmost recesses of the most complex object in the known universe, of which each of us has an example right between our ears. So stand warned: this post may well leave you spending even more time on your computer than usual! (more…)

From the Simple to the Complex, Uncategorized | No comments