Where two neurons meet, a very small gap (synapse) exists between them. The electrical impulse travelling along the axon of the neuron must convert into a chemical signal to bridge this gap. The chemicals that do this are called neurotransmitters. These so-called “chemical messengers” are involved in our different responses to situations.
Your emotions depend on fluctuating levels of neurotransmitters, which cause the activation of different parts of the brain responsible for different moods, or activate parts of the brain that trigger the stimulation of the autonomic nervous system.
- Adrenaline – released by the adrenal glands that sit on top of each kidney, adrenaline increases the flow of blood to our muscles, raises our heart rate and dilates our pupils. It is crucial in our fight-or-flight survival response.
- Noradrenaline – similar to adrenaline, the release of this chemical can result in increases levels of alertness, helping to prime us for action if needed. It also increases our blood pressure and widens our air passages.
- Dopamine – this is the addictive reward chemical that your brain learns to crave. It serves to motivate you to seek out the things you need for your survival. We can sometimes find ourselves enslaved by this ancient reward mechanism.
- Oxytocin – also known as the “cuddle hormone”, oxytocin is released when you’re close to another person. It’s essential for making strong social bonds, and it’s also a key part of why we want to trust people.