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Psychoactive drugs: Depressants and opiates

Video transcript

your consciousness is your awareness of yourself and your environment some chemicals known as psychoactive drugs can alter your consciousness by affecting your perceptions and moods there are three main categories of psychoactive drugs I want to tell you about in the next few videos depressants stimulants and hallucinogens so let's start with depressants depressants are drugs that lower your body's basic functions and neural activity for example your heart rate reaction time processing speed that kind of thing the most popular depressant one you might not even think of as a consciousness altering drug is alcohol alcohol like other depressants slows neural processing it slows your sympathetic nervous system down which is the system that usually helps you respond to dangerous situations that just means you think and act more slowly alcohol can also disrupt your regular sleep cycle specifically disrupting REM sleep when you don't get enough REM sleep then your ability to form memories and new synapses is reduced and because of that alcohol can have a negative impact on your memory and learning processes and finally and what you probably know about alcohol is that it's a disinhibitor meaning it removes your inhibitions people who've been drinking are more likely to act on their impulses which often leads to impaired judgment and reduce self awareness and self control so that mostly covers what we want to talk about with alcohol another type of depressant is a barbiturate which used to be called a tranquilizer but that term isn't really used that much anymore and clinically barbiturates are usually used to induce sleep or reduce anxiety they work by depressing your central nervous system activity some side effects of barbiturates are reduced memory judgment centration and when combined with alcohol they can lead to death as a side note combining alcohol with drugs is generally a bad idea your body can only handle so many foreign substances at one time so take it easy the most commonly prescribed depressant drugs are benzodiazepines which are sometimes called benzos for short benzos like most other depressants enhance your brains response to gaba which is an inhibitory neurotransmitter basically how it works is that benzos open up gaba activated chloride channels in your neurons which allows more chloride ions to enter the neuron and make it more negatively charged which then makes it more resistant to excitation and that's why these drugs are often prescribed as sleep aids or anti-anxiety medications and there are three types of benzos short-acting intermediate acting and long acting short and intermediate acting benzos are usually prescribed for insomnia whereas the long acting benzos are preferred for anxiety the last type of drug I'll tell you about in this video is opiates and opiates are usually used to treat pain and they can also be used to treat anxiety some examples of opiates you may have heard of are heroin and morphine the reason opiates are used to treat pain is because they act at your body's receptor sites for endorphins which are your body's natural pain reducers this mechanism is actually what makes opiates a different class of drugs than depressant although these drugs can be used for some overlapping purposes such as anxiety reduction depressants act on gaba receptors while opiates act on endorphin receptors high doses of opiates can lead to euphoria which is why people end up taking them recreationally all these drugs can be very addictive so that's why doctors always have to be very careful when they prescribe painkillers sleep aids or any other type of depressant drug or opiate