Dr Emeran Mayer: Your Gut Processes Emotion and Regulates Health While You Sleep
Your brain isn't the only organ processing your day while you sleep. Dr. Emeran Mayer explains the circular processing of emotion and memory that goes on between your brain and your digestive system, and how the latter can "dream".
26 October, 2016
There is so much more going on in your sleep than you think.
<p>In his <a href="http://bigthink.com/videos/emeran-mayer-on-depression-and-the-mind-gut-connection">first video</a> for Big Think, Dr Emeran Mayer – gastroenterologist and author of <i>The Mind-Gut Connection</i> – described what is called our "second brain". The gut is no ordinary body system; it’s intelligent and independent, in that it consists of about 100 million nerve cells sandwiched between layers of the gut running all the way from the esophagus to the end of the large intestine. This ‘second brain’ in our gut, and our regular brain use the same neurotransmitters and are connected through neural, endocrine, and immune pathways, so it truly is an integrated intelligent system with information flowing in both directions.</p>
<p>This becomes interesting when you start asking questions about sleep and its relationship to health. We all know sleep is vital to bodily function, but usually we’re focused on our mind activity. What are we dreaming about? Are we processing the day’s emotional turbulences? Are we getting enough sleep to let the brain do its thing?</p>
<p>Dr. Mayer explains that your gut is also critically important during sleep, and is affected by your sleep patterns. When you fall asleep and your stomach is empty, your gut commences 90-minute cycles of intense contractile waves that migrate from your esophagus all the way down to the end of your large intestine. It’s a cleaning process that removes residue from the gut and keeps microbial bacteria in check. We’ve always known that missing out on sleep makes us foggy-headed and far from our best selves in terms of cognition, but if our sleep is disturbed or we aren’t getting enough of it, or we are eating too much in the night, the gut won’t have a chance to properly clean itself. Left unregulated, bacteria will develop into abnormal colonies, the health implications of which can be enormous. </p>
<p>What’s more, Mayer points out that, in a way, your gut dreams too. Just as the expressions on your face reveal your internal emotions, your gut is equally reflective of your daily ups and downs – whether it takes the form of butterflies, nervous bowels, emotional nausea, or more subtle physiological changes that fly under the radar. And just as an event that didn’t really seem important in the daytime can completely take over your dreams at night, your gut too is encoded with these experiences and must digest them. "Many of these memories have a gut-feeling component because every time we have an emotion during the day there’s always a counterpart at the gut level that, through these sensory pathways, goes back to the brain." During sleep, memories are retrieved and processed in the brain, which includes re-living the corresponding gut feelings we had during the day.</p>
<p>With this insight, one has a whole new appreciation for the gut or "second brain", and its nocturnal mechanisms are a fascinating and urgent reminder that sleep is more important than ever. </p>
<p>Dr Emeran Mayer's most recent book is <a href="https://www.amazon.com/Mind-Gut-Connection-Conversation-Impacts-Choices/dp/0062376551"><i>The Mind-Gut Connection: How the Hidden Conversation Within Our Bodies Impacts Our Mood, Our Choices, and Our Overall Health</i></a></p>.<p><a href="https://www.amazon.com/Mind-Gut-Connection-Conversation-Impacts-Choices/dp/0062376551"><img height="150" src="%5Cr%5Cnhttps://s3.amazonaws.com/edge-misc-assets/Book+Covers/Emeran+Mayer+1.jpg" width="225"></a></p>
Keep reading
Show less
Depression, Serotonin, and the Mind-Gut Connection
Neuroscientists now think of the gut as a "second brain"; it independently controls your digestive processes and is in constant conversation with your main brain. What do they talk about? Depression, theorizes Dr Emeran Mayer.
18 October, 2016
We all feel things in our gut – intuitions that give us subtle physiological alerts, stress and anxiety that unsettle us, bad reactions to food, and conversely feelings of contentment from the right food, or flutters from an exciting experience. But according to Dr Emeran Mayer, what we feel is just a small fraction of what’s going on in a region of our body that is still quite mysterious – even to the experts.
<p>In his new book, <i>The Mind-Gut Connection,</i>, Dr Mayer writes: "Your gut has capabilities that surpass all our other organs and even rival your brain. It has its own nervous system, known in scientific literature as the enteric nervous system, or ENS, and [is] often referred to in the media as the "second brain.""</p>
<p>As Mayer describes, this second brain consists of about 100 million nerve cells sandwiched between layers of the gut running all the way from the esophagus to the end of the large intestine. This ‘second brain’ and our regular brain use the same neurotransmitters and are connected through neural, endocrine, and immune pathways, so it truly is an integrated intelligent system with information flowing in both directions.</p>
<p>What makes the second brain unique from other organs is that – in animals at least – when it’s separated from the main brain it continues to pilot its complex activities on its own. </p>
<p>The system is extremely interesting to researchers because of this independent streak, and the effect that it may have on our mental health. After his many years of research, Mayer humbly says it’s "highly plausible" that there is a connection between the gut and mental health conditions such as depression. Scientists from the University of North Carolina have found that gut bacteria produce neurotransmitters like serotonin, dopamine and GABA, all of which have associations with our mood. Often the medications people with depression take are designed to adjust the uptake of these neurotransmitters, a treatment scientists at the time designed thinking only of the brain, but it may now also have implications in the microbiome.</p>
<p>What makes it even more intriguing is that more than 95% of our body’s serotonin is produced and stored in the gut in specialized enterochromaffin cells, says Dr Mayer, adding: "By far the largest store of the molecule that plays such a big role in modulating our mood and our wellbeing – also appetite, pain sensitivity – is stored in the gut."</p>
<p>In recent years, the microbiome has come to the fore of scientific research, hinting at the wide reach of its sway over the body and mind. There is still a long, long way to go in understanding direct causations, but when that happens, there is no doubt our comprehension of this second brain will affect our well-being and quality of life in a big way. </p>
<p>Dr Emeran Mayer's most recent book is <a href="https://www.amazon.com/Mind-Gut-Connection-Conversation-Impacts-Choices/dp/0062376551"><i>The Mind-Gut Connection: How the Hidden Conversation Within Our Bodies Impacts Our Mood, Our Choices, and Our Overall Health</i></a></p>.<p><a href="https://www.amazon.com/Mind-Gut-Connection-Conversation-Impacts-Choices/dp/0062376551"><img height="150" src="%5Cr%5Cnhttps://s3.amazonaws.com/edge-misc-assets/Book+Covers/Emeran+Mayer+1.jpg" width="225"></a></p>
Keep reading
Show less
