How The Nervous System & Immune Systems Interact
- 3 mins read
- Written by: Dr. Jatin Bhide
Psychoneuroimmunology might sound like something complicated, but it actually isn’t! Simply put, it is a study of the link between the nervous system and the immune system, and psychological state.
You’re probably wondering how a system that makes us walk, talk and feel, and the one that protects us from getting sick are connected, right? Well, that’s just how marvellous our bodies are. These two are hardwired into each other to look out for us in multiple situations.
Let’s have a look at different ways in which the nervous and immune systems interact in our body.
In sickness and in health
Our immune system tends to get a little overboard sometimes (it takes after us). We’re lucky to have the vagus nerve, to modulate the immune response in case it tends to be too eager. However, in the case of imminent danger, we need the immune system to spring to action. When the immune system sends signals to the brain, it increases the body temperature. This is how we get a ‘fever’.
Stress gets under your skin
Under stressful situations, the brain can signal the immune system to release certain chemicals and activate some immune cells, which affects the skin. This can cause skin problems like acne, psoriasis, vitiligo, and many more.
Living in la-la land
It has been found that hypnosis and relaxation techniques improve the activity of certain cells called Natural Killer Cells. You probably guessed it from their name – yes, these cells kill bacteria and viruses. These techniques also lessen the activity of stress hormones in our bodies. This effect has been seen in the reduction of herpes virus activity.
Lick those wounds
Being mentally hurt can do more damage if you are physically hurt! Studies have shown that wounds heal better if you have social support and positive affect around you. Studies have also shown that the love hormone – oxytocin can play an important role in repairing wounds. Hence, coping effectively with stress can help your wounds heal better and make you ready to get back in the game faster.
A lot on your plate
Certain inflammatory immune mediators can act on a part of our brain called the hypothalamus. This can happen during stressful situations and other stimuli. These mediators can have an impact on our hunger and appetite, which is controlled by the hypothalamus. Tumour Necrosis Factor (TNF) is one such mediator and can stimulate neurons to make a hormone called leptin. Leptin can make you lose your appetite and also lead to weight loss.
A helping hand
We know that Acquired Immunodeficiency Syndrome (AIDS) is a disease that weakens our immune system. The disease itself is associated with a lot of stigma and stress. This can take a heavy toll on the mental health of AIDS patients. This is why psychoneuroimmunology is being used to develop hardiness in these patients. Support groups that can help maintain a positive and trustworthy atmosphere around AIDS patients have proven useful and prevent their immunity from deteriorating further.
It is pretty evident that the immune and nervous systems share a very intimate relationship and are important for each other. To live a healthy life, we need to keep both these systems in check. Let us strive to do just that.
- Broadbent E, et al. The psychology of wound healing. Curr Opin Psychiatry. 2012;25(2):135-40.
- Klok MD, et al. The role of leptin and ghrelin in the regulation of food intake and body weight in humans: a review. Obes Rev. 2007;8(1):21-34.
- Ader R, et al. Psychoneuroimmunology: conditioning and stress. Annu Rev Psychol. 1993;44:53-85.
- Honeyman JF. Psychoneuroimmunology and the skin. Acta Derm Venereol. 2016;96(217):38-46.