What's does serotonin do

Answer 1

Serotonin is a 'transmitter' chemical - it helps to pass nerve impulses from one nerve cell (neurone) to the next over the synapse (gap between two neurones).

It works like this;

1. When a nerve impulse travels the length of a neurone and reaches the end it must 'jump' the gap between one neurone and the next.

2. To do this, the impulse triggers the release of a transmitter chemical (such as serotonin) from the end of the neurone into the synapse.

3. These transmitter chemical molecules diffuse across the gap between the two neurones, and bind to special receptor molecules on the membrane (outer skin) of the next neurone.

4. When these transmitter chemicals bind to the right receptor molecules they trigger a new impulse carrying the same 'information' as the impulse in the previous neurone.

Serotonin is simply one of the many 'transmitter' chemicals.

Serotonin can also do the following:

1. It gives us self-confidence, a feeling of safety and security.

2. It causes us to feel sleepy.

3. It increases our appetites.

The part of the brain where it does each of these 3 things is a different part of the brain from the part where the other 2 things occur. Thus, for example, increasing serotonin in the part of the brain where self-confidence is will increase your self-confidence, but not your sleepiness. Unfortunately, we have no medications to increase only the serotonin in one part of the brain. This explains why medications to increase serotonin in the brain can also cause increased appetite and sleepiness.

Medications which increase serotonin in the brain (SSRI's such as citalopram, escitalopram, fluoxetine, paroxetine, and sertraline and SNRI's such as venlafaxine and duloxetine) give us more self-confidence, and a feeling of safety and security.

By the way, serotonin also exists in our gastrointestinal tracts. In this location, it stimulates digestion. This is why such medications can cause gastrointestinal upset. But they can also help constipation.

Answer 2

Serotonin directs impulses between the brain and nerve pathways; it is largely responsible for mood.