Transcript for: Understanding Stimulants and Their Effects
[Voiceover] We talked about depressants, which depress neural activity
and bodily functions. On the other hand, we have
stimulants, which stimulate or intensify neural activity
and bodily functions. These can range from
your everyday stimulants, like caffeine, to more hardcore drugs, like cocaine, amphetamines,
methamphetamines and ecstasy. In between those extremes are nicotine, which is found in cigarettes. If you've ever tried to stay awake by drinking coffee or a
soda or something like that, then you know that caffeine adds energy and can disrupt your
sleep for several hours. Nicotine actually acts similarly. It increases your heart
rate and blood pressure and arouses the brain to a
state of heightened alertness. Nicotine also suppresses your
appetite, which is one reason that people sometimes gain
weight when they quit smoking. Without the nicotine, their appetite return, so they eat more. In very high levels, nicotine can actually cause muscles to relax
and cause the release of certain neurotransmitters
that may reduce stress. That's your body's natural response to try to counteract all
that heightened alertness and tension caused by the nicotine. Both caffeine and nicotine
are physiologically addictive, meaning that your body grows accustomed to them and starts to experience negative reactions when
you don't get enough. For example, you might know people who drink a lot of coffee everyday, or you might be one of those people. If you don't get your coffee, think about if you
experience any headaches, irritability, difficulty
concentrating, even depression. That's withdrawal symptom
from the caffeine and coffee. Nicotine is even more addictive than that. This is one reason that it's
so hard to quit smoking. Once the body gets used to nicotine, its absence can lead to
withdrawal symptoms like anxiety, insomnia, distractibility,
and irritability. Cocaine is an even stronger stimulant. It causes your brain to release so much dopamine, serotonin
and norepinephrine that it basically depletes
your brain's supply. Once the drug wears off, you experience this intense crash and
become very depressed. Regular cocaine users can
experience emotional disturbances, suspicion, convulsions, cardiac
arrest, or respiratory failure. Amphetamines and methamphetamines also trigger the release of dopamine, and meth can cause a feeling of euphoria that can last up to eight hours, but after that wears off,
people experience, again, intense irritability, insomnia, or even seizures and depression. Meth is highly addictive, and people will literally just devote their
lives to getting another fix. Long-term addicts might
even lose the ability to maintain normal levels of dopamine, as their brain tries to
adjust to the intense highs.