Name: How your ‘second brain’ changes the way you think | BBC Global
Uploaded: 2025-05-07T21:01:10.000Z
Duration: 2 min 21 s
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We all know the brain is fundamental in influencing how we think, feel and behave,

but we also have a second brain, and it plays a surprising role in shaping our thoughts, moods, and even our mental health.

Relative clauses (Restrictive vs. nonrestrictive)

This second brain is in our gut, which is filled with all kinds of bacteria, fungi and microorganisms.

They are collectively known as the gut microbiota.

They play a vital role in helping us stay healthy from our digestion, metabolism and disease prevention.

But what's lesser known is that they can influence our behavior fom our mood to our memory.

The idea of a gut-brain connection has been established since the 19th century.

A surgeon named William Beaumont worked with a patient, Alexis St Martin, who lived with a hole in his stomach from a gunshot wound.

In a series of dubiously unethical experiments, he learned how St Martin's emotions influenced his digestion, his injury therefore provided Beaumont with the unique insight into the inner workings of the gut.

Fast forward to the present day, and it's clear that there are numerous ways our gut affects our mind.

Our microbes regulate the immune system, producing chemicals that directly impact brain activity, and even influence the development of neural pathways in the brain.

Research on animals has shown that germ free mice raised in sterile environments without any microbes are more anxious and less social compared to those with a normal range of microbiota.

While mice on antibiotics, which reduce microbes, have been found to be more hyperactive, prone to taking risks and showed a decline in their memory.

A better understanding of how our gut impacts our behavior could help scientists find better treatment for mental health conditions.

For example, reduced levels of certain bacteria are common in individuals with mental health concerns, one study found that taking a probiotic tablet helped those with depression.

Although research in humans in this area is still emerging, it's clear that eating well doesn't just benefit the body, but also the mind.