Neurotransmitters act as chemical messengers in the synapse between neurons, there exist neurotransmitter pathways that are clusters of neurons and projections that communicate using a particular neurotransmitter. Four motivationally relevant neurotransmitters are
- Dopamine, generates good feelings of reward
- Serotonin which influences mood and emotion, serotonin deficiency is associated with depression.
- Norepinephrine which regulates arousal and alertness
- Endorphin which inhibits pain, anxiety and fear by generating positive affect.
Hormones such as cortisol are released in response to stress via the hypothalamus- pituary-andrenocortical physiological pathway due to social-evaluative threats.
Testosterone is associated with high sexual motivation.
Oxytocin is a hormone produced by the hypothalamus and is colloquially known as a bonding hormone,"tend and befriend" stress response that enhances reponses associated with counsel, support and nurturance (Reeve 2009 : 67) . This makes it sound like a wonder molecule for prosocial behaviour, of course the reality is more complex.
Amusingly, IO9 which occasionally tries to be funny like Cracked.com with "lists" did one on why oxytocin is such a great molecule but also features another more balanced article. The hype surrounding oxytocin began with a study by Kosfield & Heinrichs (2005) in which participants played games of trust while sniffing Oxytocin. In fact its influence is dependent greatly on the orientations of the individual and is one of many interactions.
Kosfeld, Michael: Heinrichs, Markus: Zak, Paul J: Fishchbacker, Urs & Fehr, Ernst. (2005). Oxytocin increases trust in humans. In the International Journal of Nature. (June 2005). Pages 673- 676.
Reeve, Johnmarshall. (2009) . Understanding Motivation and Emotion. (5th Edition). Published by John Wiley & Sons. Pages 62- 71.