DRUGS AND THE NERVOUS SYSTEM

[Music] and despair they can also bring health drugs affect the body in many different ways if bacteria are causing a disease a doctor is an antibiotic or some other drug that kills bacteria it might be the lungs the heart helped by some special drug that affects that particular organ some drugs work on the nervous system the complex system that regulates every part of the body these drugs work in many ways ever felt like this hot feverish achy you remember the last time you stayed home from school well your mother might have given you a drug aspirin aspirin helps aches and pains and it also lowers fevers in part by working on the nervous system the aspirin tablet is absorbed through the stomach and intestines within a half an hour molecules of the drug will reach the cells of the brain there it will begin to affect that aching feeling that begins in the muscles in the microscopic spaces between the muscle fibers there are countless nerve endings called receptors that pick up messages from the aching muscles each receptor sends signals along a nerve fiber into the spinal cord and up into the brain these electrochemical impulses pass into a lower part of the brain which controls messages having to do with pain from here impulses pass to the higher part of the brain the cortex probably where our sick friend forms the idea that his muscles ache he thinks how uncomfortable he is impulses race to the parts of the brain that will move his muscles to change position messages go out still feel terrible well the aspirin will help any minute now one of the several effects that aspirin has is on the part of the brain that controls pain impulses pain impulses still come in but as the aspirin begins to work not as many go out our friend just doesn't feel the ache as much therefore by careful use of a drug he has changed one action of the nervous system aspirin also works in another way by making you flushed and making you sweat which helps to lower your fever the aspirin works on a special part of the brain that controls the temperature of the body this is one of the nerve centers that controls the working of your body's organs without any conscious thought on your part at all when the special brain center begins to be affected by the aspirin it sends out impulses to the sweat glands causing them to produce more moisture when the sweat evaporates it cools the body at the same time other impulses cause the surface blood vessels to expand they then carry more of the overheated blood to the surface of the body where it can cool complicated very and there are dozens of other drugs that a doctor can use to change the action of a person's nervous system in dozens of other ways only a doctor has the knowledge to know which to use or how much to use the wrong drug or the wrong amount can be a poison for instance if two aspirin tablets will help your fever why shouldn't 20 make you well listen don't try it out too many little kids have thought sweetened little aspirin tablets were candy and have died speaking of poison what would you think of someone who decided to put a bowl full of strict nine into a system impossible well certain materials have fumes that are deadly poison [Music] some people breathe in chemical fumes for kicks what a gas huh molecules of poison are carried from the lungs deep into the cells of the brain along with the kicks come nausea headaches dullness shaking and other feelings that aren't so much fun if you breathe in these fumes for too long you can easily kill yourself now most drugs can be poisonous but when they are used with a doctor's instructions they can have real medical value there are two principal kinds of drugs that affect the nervous system one is the kind we call a stimulant now this is a drug that stimulates certain brain cells to work much faster the other is a depressant this is a drug that slows impulses sleeping pills or barbiturates are the commonest kind of depressant drug and useful too when they are taken properly when people take downers for kicks a small amount sometimes makes them feel relaxed and friendly mellow but slowed down if they take more the person gets sluggish gloomy sometimes wants to start a fight and then you see a brain out of order throws the whole body out of order breathing is dangerously slowed down the heart is very weak blood pressure drops dangerously this collapse may be more than a deep deep sleep in just one city about 450 people die each year from barbiturates hours later the body labors to get back to normal it's a strange kind of kicks now another kind of depressant both useful and dangerous comes from the opium poppy the various drugs that are made from opium patient is in severe pain codeine is another drug which your doctor may have prescribed in a cough medicine it has a special effect on the brain center that controls your coughing the most dangerous drug of all is heroin a person who starts using heroin gets an intense feeling of pleasure for a while [Music] then he gets very drowsy and unable to think clearly everything gets blurred he sits dope when the drug wears off he wants that pleasant feeling again but he has to keep increasing the dose to get that same high feeling he had when he first tried it [Applause] [Music] the real disaster of heroin creeps up quietly after a while if he doesn't get the drug he gets violently sick and may even die he's an addict now with a habit that's almost impossible to get rid of he spends the rest of his life just trying to keep up his supply of heroin usually by stealing i mean if that's the only way he can get enough money to buy it he does it and somehow the saddest part is that soon the drug doesn't even make him feel good anymore you see he needs it just so he won't feel sick [Music] the other principal drugs that work on the nervous system are the stimulants or uppers that cause part of the brain to work faster one of the most dangerous is amphetamine doctors sometimes will prescribe these in small amounts for instance to help patients who are terribly tired all the time or depressed but suppose somebody takes several uppers looking for kicks just want to have a good time what might this disturbance in the brain cells do to the body well the heart often beats irregularly the walls of the blood vessels will tighten which shoots the blood pressure up the person becomes jittery and restless billions of extra impulses bring confusion [Music] the person becomes irritable tense anxious you may fly into a rage [Music] when the effects finally do wear off you will be terribly tired and usually very depressed another drug that affects the nervous system is marijuana marijuana changes the senses the way one sees and feels about the world sometimes marijuana makes a person feel lively and excited laughing more often it makes him quiet and withdrawn you see it distorts the sense of space and of time now the brain may say that a car is going this fast instead of this fast unlike depressants and stimulants marijuana doesn't seem to carry the danger of severe damage to the body and it doesn't have heroin's danger of physical addiction but many scientists believe that young people who use marijuana often regularly run the danger of becoming dependent psychologically dependent on it they lose interest in normal life they let the world go by then there are the psychedelic drugs principally lsd a brain under the influence of lsd distorts the senses your feelings smell sight and sound something may be commonplace an everyday occurrence but with lsd it takes on great significance [Music] lsd can give great pleasure but there are grave dangers involved one of them is that it destroys judgment some people believe they can fly some people feel godlike deathless not long ago this happened another risk is a bad trip an experience that can be like a horrifying nightmare from which you just can't escape and then particularly for young people with personal problems there's a real danger of getting sick mentally sick young people distort their nervous systems with drugs for different reasons they may want to be part of the in crowd always be with it to seem big and unafraid you know they may be looking for excitement for kicks some have problems that they just aren't ready to face yet what do you think these young people are like would you guess that they are likely to be strong responsible wise mature for their age [Music] might some have problems in getting along in the world what do you think [Music] you