Steep Hill Lab - laboratory scientifically testing cannabis - made interesting discovery: One of the terpenes in cannabis β-Myrcene (also found in Mango) produces famous “Couch-lock” effect.
It is said that Mango is friend of cannabis smokers, now we know why … 
http://steephill.com/science/terpenes
#β-Myrcene
Formula: C10H16
Molecular Mass: 136.1252 g/mol
Boiling Point: 168 °C (334 °F)
Vapor Pressure: 7.00 mmHg ( 20 °C)
β-Myrcene is a monoterpene, and for a wide variety of reasons, one of the most important terpenes. It is a precursor in the formation of other terpenes, as well. β-Myrcene is found fresh mango fruit, hops, bay leaves, eucalyptus, lemongrass and many other plants. β-Myrcene is known to be anti-tumor, anti-inflammatory, and used in the treatment of spasms. It is also used to treat insomnia, and pain. It also has some very special properties, including lowering the resistance across the blood to brain barrier, allowing itself and many other chemicals to cross the barrier easier and more quickly. In the case of cannabinoids, like THC, it allows it to take effect more quickly. More uniquely still, β-Myrcene has been shown to increase the maximum saturation level of the CB1 receptor, allowing for a greater maximum psychoactive effect. For most people, the consumption of a fresh mango, 45 minutes before inhaling cannabis, will result in a faster onset of psycho activity and greater intensity. β-Myrcene can be used in this same manner to improve uptake with a wide variety of chemical compounds.
Less well known is that fact that high β-Myrcene levels in cannabis (usually above 0.5%) result in the well known ‘couch lock’ effect of classic Indica strains of cannabis; Sativa strains normally contain less than 0.5% β-Myrcene.
