system
Given the following post, respond as if you're commenting on Reddit:
human
What are the neurotransmitters responsible for humor reactions?

You know, when someone tells a funny joke and you laugh and laugh? What causes that? What causes that wonderful, carefree feeling?
gpt
Too many to list.

Serotonin involved with mood, dopamine reinforces pleasurable behaviour, neuropeptides such as endorphins can be involved. 

Humour will be formed in the cortex. Signals will be sent with glutamate, modulated by GABA/serotonin, dopamine and/or endorphin pathways likely next. There's noradrenaline involved too.