Is Your Nervous System Being Hacked by Bacteria in Your Gut?
Written by Editor   
Thursday, June 25, 2015 09:47 AM
Quick Brief:  Bacteria in the gut stimulating the vagus nerve can have a direct effect on the nervous system and upon the development of the brain and emotions.


The vagus nerve brings information from all over the body to the brain – but is it being hacked by the bacteria in our gut?  Some 80 per cent of the traffic along the vagus nerve is sensory information sent up to the brain by the body, and researchers are beginning to realise this has a significant influence on the mind. There is also now strong evidence from animal studies that the gut’s microbial residents – known as the microbiome – can activate the vagus nerve, with effects on brain and behaviour.

The link between gut flora and disorders such as depression and autism has been recognised for some years. Recent experiments have demonstrated that mice with behavioural disorders (equivalent to certain human mental health problems) have a significantly different microbiome make-up from healthy mice, and that these bacteria may be causing the problems.

The gut’s influence over mental health can begin before we’re even born. One-fifth of all people with schizophrenia were exposed in the womb to viral or microbial infections because their mother became sick while pregnant, scientists estimate. Gut flora can control these pathogens and modify brain development and behaviour, researchers have found.

Bacteria that inhabit the intestines secrete waste products that can cause inflammation. They can also produce neurotransmitters, including serotonin and dopamine. This generates electrochemical signals that travel up the vagus nerve, triggering chemical changes in the brain that affect behaviour. The vagus even appears to differentiate between non-pathogenic and potentially pathogenic bacteria and induce feelings of anxiety or calm depending on the stimulus, scientists believe.