Each of us have worse days that follow, for example, after a sleepless night or as a result of too many duties. We feel then a big drop in energy, we do not have strength and willingness, we can not focus and mobilize to do anything. At such moments often we reach for stimulants to increase our psychomotor performance, sharpen the senses and increase motivation.
Stimulants are natural psychoactive substances (eg. alkaloids) and synthetic (eg. modafinil), stimulating the sympathetic nervous system and the central nervous system (CNS). They increase the activity, productivity and efficiency, improve psychomotor performance, maintain alertness and prevent fatigue, abolish the need for sleep, improve concentration and focus.
Typically, they operate physiologically by blocking adenosine receptors, the inhibition of GABA, and stimulating the production of neurotransmitters (dopamine, norepinephrine, epinephrine).