Skip to main content
. Author manuscript; available in PMC: 2014 Jul 15.
Published in final edited form as: Med Hypotheses. 2008 Oct 31;72(1):14–22. doi: 10.1016/j.mehy.2008.07.059

Figure 1.

Figure 1

Brain Reward Cascade. In this cascade, stimulation of the serotonergic system in the hypothalamus leads to the stimulation of delta/mu receptors by serotonin to cause a release of enkephalins. Activation of the enkephalinergic system induces an inhibition of GABA transmission at the substantia nigra by enkephalin stimulation of mu receptors at GABA neurons. Both the endocannabinoid and glutamate receptors influence GABERGIC activity. This inhibitory effect allows for the fine tuning of GABA activity. This provides the normal release of dopamine at the projected area of the n. accumbens (a major reward site of the brain). With permission of Gene Therapy Press [44].