During centuries in human history some chemical with plant and rarely with the animal origins were either used or abused by mankind; without any clear knowledge about the brain. There is substantial evidence show the use of these chemical by old age physician as well as magician so called medicine man and/or woman; but also by some ethnic and/or religious society; to fulfill the ethnic ceremonies and or spiritual occasions.
Even in the present time with huge knowledge of brain science; some substance such as nicotine as well as alcohol were used commonly either with and/or without insight to the nature of these substance in considerable societies. Recent knowledge shows that these substance in fact are either mimetic or blockers of the brain neurotransmitters; which were called “Drug” in medicine.
Molecules similar to these drugs either release to stimulate or inhibit in the brain synaptic cliff in”key & lock” manure. Some other may used inside the brain cell as a precursor, receptor blocker, and uptake blocker etc. Gordon Wasson and his wife Valentina as a pediatrician was interested in the medical effects of plants; and made several expeditions to Mexico learning the properties of these agents.
Although early work on the acetylcholine as a neurotransmitter substance in the heart goes back to 1970 by Otto Loewi 1921; the frontiers in listing these chemical in the brain comes from the mid-20th century. These frontiers gathered substantial evidence to show that most of these chemical already exist in human brain naturally.
These agents as a brain neurotransmitters consist of acetylcholine, noradrenalin, dopamine, serotonin, enkephalins, GABA (gama-aminobutyric acid), as well as amino acids such as glycie, glutamic acid, and histamine. Many more of these chemicals also discovered in recent years; and tremendous knowledge growing each day in this field. All of these chemicals are available both in the brain and also either synthetically or naturally outside the brain. The roles of these substances and/or neurochemicals in the brain are clear by now.
An example are acetylcholine, noradrenalin, dopamine, and serotonin; which pay a crucial role in memory, and other brain processing such as affection, and temper in human. Abuse of these substances may reduce synthesis, turnover, demolition, and receptor in the brain; on which enhance the further need to these agents; causing addition. An example of such condition may accrue with nicotine and alcohol abuse; as a mimetic for acetylcholine, and GABA directly; and others indirectly.
The neuroscience is in debit of frontiers in neurochemistry, and psychopharmacology as same as physiology, and medicine to grow. These neuroscientists such as George Aghajanian (1932), Solomon H. Snyder (1938), Albert Hofmann (1943), Marianne Fillenz (1980), Abdolvahab Vahabzadeh (1990) paid substantial knowledge to the neuroscience.
