The following Mark's Daily Apple article was written by Mark Sisson,

and is narrated by Tina Lehman.

This is your brain on bugs.

How gut bacteria affect mental health. Within the human gut

lies a second brain, a vast network of neurons located along the intestinal lining. It's called

the enteric nervous system, enteric as in pertaining to the gut. And for years years researchers assumed its sole province lay in regulation

of the digestive process. Researchers now know that the enteric nervous system also relays and

sense neurotransmitters like serotonin and gava, responds to emotions, and has a direct conduit to the brain via the vagus nerve.

The gut is not the site of higher-level cognition.

The neurochemical processes responsible for writing emails and doing trigonometry

occurs solely in the brain.

But though decision-making and conscious thought happen up top,

the gut has a lot of input on how those thoughts and decisions develop.

About 90% of traffic along the Vegas flows from gut to brain, and it's not all information about intestinal contractions.

The second brain is likely the province of instinct, subconscious response, and emotion.

In other words, gut feeling, gut instinct, butterflies in your stomach, and got the guts,

aren't just figures of speech. They hint at real physiological processes occurring along the gut brain axis. Emerging evidence is showing that our enteric nervous system and the gut bacteria probiotics and probiotics that compromise

and affect it have effects on how we think, feel, perform, and respond to the world around

us. Let's take a look.

Depression.

Depression is an epidemic.

More than one in ten Americans over the age of 12 take antidepressants.

...