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AP Psych



Unit 2

2.5 Influence of Drugs on Neural Firing

3 min readnovember 11, 2020


Megan Revello


Dalia Savy


  • substance use disorder
  • depressants
  • opiates
  • nicotine
  • ecstasy (MDMA)
  • near-death experience
  • psychoactive drug
  • addiction
  • alcohol use disorder
  • stimulants
  • cocaine
  • hallucinogens
  • THC
  • tolerance
  • withdrawal
  • barbiturates
  • amphetamines
  • methamphetamine
  • LSD


Psychoactive drugs refer to any substance that alters our perceptions and moods. Oftentimes these substances are illicit and can lead to substance use disorders and addictions. People who suffer from addiction may experience negative withdrawal symptoms when attempting to quit using the substance because their body has grown accustomed to it.
Furthermore, the more they use a substance, the more tolerant their body becomes, causing them to have to take more and more of the substance to achieve the same high. It becomes a whole cycle of addiction that takes lots of strength to break.
We actually consume drugs more than you think! If you drink coffee, tea☕, or coke🥤, you are consuming the psychoactive drug called caffeine.
However, addiction differs majorly from everyday use! If the drug disrupts someone's life, daily schedule📅, or disables them to do something, it becomes a problem and should be looked👓 into by an expert.
There are three main categories of drugs:


Depressants are one classification of drugs that reduce or slow our neural activity and body functions. A few depressants are alcohol, barbiturates, and opiates.


Alcohol is the most commonly used depressant in the world. You see it everywhere, at celebrations🥂, at parties🍻, basically at any social gathering. However, its effects are drastic and people often get way too carried away with the consumption of alcohol.
The main effects of alcohol include slowed🦥 neural processing, memory disruption, reduced self-awareness, and reduced self-control. Low doses of alcohol relax the drinker by slowing down the sympathetic nervous system but large doses cause all of the above.
Ever hear of blackouts? After one wakes up, they have no memory of the event. This is because alcohol suppresses REM sleep.
Addiction could lead to alcohol use disorder, which is marked by tolerance, withdrawal, and the need to continue drinking. Unfortunately, millions of people have this disorder and it has drastic effects such as shrinking the brain🧠


Barbiturates are tranquilizers that suppress the activity of the central nervous system. They are prescribed to reduce anxiety, induce sleep😴, and prevent seizures. However, the combined use of barbiturates and alcohol is very deadly.


Opiates also depress neural activity, temporarily lessening pain and anxiety as well. Opiates, such as morphine and heroin, stop the production of endorphins. Endorphins are the body’s natural painkiller and since opiates mimic endorphins, stopping the drug could mean death by overdose. As a result of the pleasure felt by taking opiates, they are extremely addictive.


Stimulants are another classification of drugs that are known to excite neural activity and speed up body functions. Drugs that fall into this category include nicotine, amphetamines, methamphetamine, cocaine, ecstasy, and MDMA.


Nicotine is found in the highly addictive drug, tobacco. Smokers develop a quick tolerance to nicotine and are very prone to withdrawal symptoms. Smoking has so many horrifying effects that it actually decreases life expectancy, killing off many people at a young age. It is also correlated with higher rates of depression and divorce.
  • Within 7 minutes of smoking a cigarette, nicotine causes a signal to be sent to the central nervous system, telling it to release several neurotransmitters:
    • Epinephrine and norepinephrine diminish appetite🍔 and boost alertness😳
    • Dopamine and serotonin calm anxiety and reduce the ability to feel pain
    • These short term rewards of smoking have a long term price to the body


Cocaine is also a highly addictive drug, producing alertness and euphoria. Euphoria is a state of excitement that occurs as a result of the brain being depleted of dopamine, serotonin, and norepinephrine. However, within an hour of taking cocaine, a crash of depression comes upon your body. This leads to mood swings, cardiac arrest, or failure to breathe.


Hallucinogens are another classification of drugs that are known to distort perception and evoke sensory images without any actual sensory input. THC, the active ingredient in marijuana, is a mild hallucinogen. Other hallucinogens include LSD and psilocybin (mushrooms). Hallucinogenic experiences are often similar to the altered state of consciousness that occurs when people have a near-death experience.
Just always remember when taking AP Psychology -- the effects of everything depend on genetics, user expectations, and social context.

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