Psychoactive plants central nervous system

Rodriguez et al (1982) noted that psychoactive compounds also often kill gastrointestinal parasites. They suggested that humans first used the plants to control parasites and discovered the effects on the central nervous system in the process. 

Cannabis sativa plants contain at least 400 different compounds, of which as many as 60 are structurally related to 5 -tetrahydrocannabinol (5 -THC), the primary psychoactive constituent of cannabis. When cannabis is smoked, hundreds of additional compounds are produced by pyrolysis, which may contribute to both acute and chronic effects (Abood and Martin, 1992). The central nervous system actions of canna-binoids are mediated primarily through the CBj receptor. A second type of cannabinoid receptor, termed the CB2 receptor, is distributed primarily in the periphery (Gifford et ah, 1999). Activation of central cannabinoid receptors modulates neurotransmitter release at... 

Psychoactive substances (including plants) are those that alter some aspect of the mind including behavior, mood, anxiety, cognition, and well-being [61]. They may be classified in three types a) depressors of Central Nervous System (CNS) activity, such as neuroleptics, anxiolytics, and hypnotics b) CNS stimulants - antidepressives and amphetamines, mainly and, finally, c) disturbers of the CNS - hallucinogens [62]. 

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