Are Our Gut And Brain Connected?

Have you ever experienced butterflies in your stomach when your crush texts you or bloating when nervous? Let's see how it happens and why you feel it.

 We hear of how people feel nauseated when they are stressed or experience dizziness and headaches when they have some sort of gut problem like lactose intolerance or eat foods that do not suit their stomach. There is a strong reason for these experiences.

The simplest explanation for these occurrences is that the nervous and gastrointestinal systems are somehow connected. Let's discuss some important aspects and the anatomy of this connection that will help us unravel the mystery of this bond.

The Gut-Brain Axis:

There is a strong bilateral connection between your gut (stomach and bowels) and your brain called The Gut-Brain Axis. This connection is chiefly due to the Vagus nerve. 

Role of Vagus Nerve:

Vagus nerve act as a highway between multiple organs and the brain, primarily between the gut and the brain.  It is a long nerve that runs from your brainstem (the lowest part of your brain) to various organs of your body, connecting them to the major regulatory organ, the brain.

 It is through this nerve that you come to know when you are hungry or your stomach is full.

This connection is mainly between the Enteric Nervous system, which runs through your gut's entire lining and is also known as the second brain, and the Central Nervous system, the brain. Hence, the Gut-Brain Axis acts as a bridge that promotes homeostasis (Maintenance) between both systems.

The primary function of ENS in the gut is to initiate digestion, absorption, and elimination processes. If you are stressed, the stress response initiated by the CNS influences the gut microbiota (microorganisms in the gut) and the ENS, modifying gut functions like peristalsis, secretions, Mucin protein production, etc., and you may feel nauseated.

GBA is a connection between the enteric system of the gut and CNS via the vagus nerve.

How Neuroendocrinology helps?

The Gut-Brain Axis is not the sole connection between the two systems. Neuroendocrine signaling also plays a demanding role in the regulation of these two systems.

The HPA-Axis, or Hypothalamic Pituitary Adrenal Axis, is a predominant regulator of stress responses and controls the gut physiologically. It is an interaction between the nervous and endocrine systems to help cope with primary functions like digestion, mood regulation, and emotions.

HPA Axis controls gut movements as well as mood with the release of some hormones in the gut as requested by the brain.

Additionally, this communication is also possible with the neurotransmitters as well as the immune system.

Role of Neurotransmitters:

Have you ever heard that serotonin makes you happy? Yes, it does. It is a happy neurotransmitter that is largely produced and stored in the gut. Approximately 90–95 percent of this key neurotransmitter is housed in our gut.

This neurotransmitter helps us with various daily life functions, including the sleep-wake cycle, happiness, optimism, appetite, mood, pain sensitivity, and bowel functions.

Therefore, when you have a disturbed sleep-wake cycle, you tend to experience diarrhea and acidity in the stomach, and when you are in extreme pain, you feel nauseous.

Summary:

• The neurological and gastrointestinal systems are connected through the Gut-Brain Axis, a strong connection between the gut and brain.
• Neuroendocrinology plays a crucial role in regulating these systems, with the HPA-Axis being a predominant regulator of stress responses and controlling the gut physiologically.