The mood-body link

The idea that the mind and body are two distinct entities has gone the same way as the dinosaurs, leg-warmers, fondue sets and the handle-bar moustache. Increasingly we are understanding that the two are inextricably bound but there is probably a lingering notion that the mind dominates the relationship. A new study though is yet another brick in the wall of knowledge suggesting that the body has a lot of sway over what is going on in your mind.

This was shown in a study done on mice that involved male mice being grouped together so that they had time to establish a hierarchy. Then an aggressive male was added to the group for 2 hours, in order to promote a level of stress within the mice. The aim was to give the mice an experience of “social defeat” which in turn leads to submissive and anxiety-like behaviour. Three groups of mice were subjected to this process either one, three or six times, and one group did not go through the stress process at all.

The groups were tested for symptoms of anxiety, and it was found that the more cycles of this process the mice suffered, the higher the anxiety symptoms. The researchers also found that the higher the stress levels of the mice the more of a type of immune cell called monocytes were found in their brains. What is important though is that these monocytes originated in the bone marrow and travelled to the brain in response to indications of stress.

The monocytes surrounded blood vessels and penetrated brain tissue in several areas linked to fear and anxiety, including the prefrontal cortex, amygdale and hippocampus. The presence of the monocytes led to symptoms of anxiety. Even more interestingly, the monocytes did not respond to the body’s own corticosteroids and so generated lots of inflammation.

It is all further evidence of the incredibly interconnected nature of your mind and body. Medically, it could point to novel treatments for anxiety if you can modulate the immune influence on brain cells. On the human level it reminds you that your being is a meshed link of body and mind. That means you treat them independently at your peril.