Substances Response of the Brain

BRAIN RESPONSE TO MARIJUANA (CANNABIS)

Hello, you can use marijuana as weed, afgan, derman, derman, plate, seal, yellow girl, antenna, winding, paspal, paspal, giya, gogo, gonca, gonca, dry, cigara, jigar, jigaralık, deligonca, ahna, henry, potato, goat, green, hemp, under sieve, black, You may have heard it called saddam, cannabis, gelatine, malt, yellow, flower, sunflower, putty, glass paste, henna, kurish, gubar, mint, but marijuana by its many names is still a substance/drug that affects the brain.

Did you know that marijuana can cause some people to lose focus on what is happening around them, making it difficult for them to concentrate? In some people, it has an increase in their physical sensations and in other people it has many other effects.

All of these different changes are the result of chemicals that affect the brain.

The average marijuana plant contains more than 400 chemicals. When smoked as a cigarette, the heat causes even more chemicals to be released.

Where does marijuana come from?

Marijuana is obtained by drying the flowers and leaves of the cannabis plant (Cannabis sativa). Like all plants, cannabis is sensitive to environmental conditions while growing. Different climate and soil conditions can change the amount of chemicals/chemical substances in the plant. This means that marijuana grown in a place like Hawaii may be chemically much harder/stronger than marijuana grown in Mexico or elsewhere.

How Does Marijuana Affect Nerve Cells in the Brain?

Marijuana causes loss of balance and control in some areas of the brain, such as areas that manage emotions, memory and decision-making.

In different ways, marijuana causes some parts of the body to react. Here are some that you may recognise:

a. How many beats per minute does the heart rate increase?

b. In which part of the body can dilated blood vessels be seen?

c. What kind of sensations accompany the feeling of panic?

d. Who is more likely to experience a daily cough and more frequent chest pain / lung infection?

Answers:

a. Marijuana can increase the heart rate up to 160 beats per minute.

b. Dilated blood vessels cause red eyes.

c. Panic may be accompanied by sweating, dry mouth and laboured breathing.

d. Similar to tobacco smokers.

How do the chemicals in marijuana change the way a person hears, sees, smells, tastes and feels things?

When a person uses marijuana, these chemicals travel through the bloodstream and quickly bind to special places on the nerve cells of the brain. These special places are called "receptors". This is because they receive information from other nerve cells and chemicals. When a receptor receives information, this causes changes in the nerve cell.

The chemical in marijuana that has a big effect on the brain is called THC - tetrahydrocannabinol (hey! Try saying that 10 times fast...).

Scientists have recently discovered that some areas of the brain have no or very few THC receptors, while certain areas have many THC receptors. These clues help to understand exactly how THC works in the brain.

One brain area that contains many THC receptors is the hippocampus, which functions for memory. When THC binds to its receptors in the hippocampus, it impairs short-term memory.

The hippocampus also communicates with other areas of the brain that process new information into long-term memory (i.e. how you remember maths lessons today or the phone number of a new friend).

When the brain is under the influence of marijuana, new information may not be recorded at all and may be erased from memory. Maybe you have heard from some people that marijuana causes uncontrollable laughter one moment and scepticism the next. This is because THC also affects emotions, possibly through the brain region called the limbic system.

And never forget this: THC can make it dangerous to do some simple things, like driving a car.

Research Continues

Some effects of THC are useful for the medical world, such as preventing nausea and stopping pain. The challenge for scientists is to achieve these beneficial effects without harmful effects.

Researchers have recently discovered a chemical substance produced by the brain that binds to the same receptors as THC, anandamide. This discovery could lead to the development of drugs that are chemically similar to THC but with less harm and could be used to treat nausea and pain.

BRAIN RESPONSE TO STEROIDS

Hello, in this section, we're going to explore some fascinating facts about anabolic steroids. Some of this information has only recently been discovered by scientists.

Anabolic steroids are an artificial version of a hormone we all have, testosterone (yes, testosterone is present in women as well as men). Testosterone not only gives male sex characteristics but also causes muscles to grow.

Some people take anabolic steroid pills or have injections/needles ('anabolic' means development or growth) because they want to build up their muscles quickly. But these steroids also have other effects. They can cause brain and body changes that increase the risk of disease, and they can affect mood.

Do anabolic steroids really make the body stronger?

You may have heard that some athletes use anabolic steroids to enlarge their bodies and increase their endurance. Maybe you "ve even seen an anabolic steroid user whose muscles get bigger over time.

But while anabolic steroids make people stronger on the outside, they make them weaker on the inside. For example, anabolic steroids can weaken the immune system (the body's defence against disease and germs). They can also cause liver damage or cancer, even in young people. They permanently stop bone development in growing young people. This means that a growing teenager who uses steroids will not reach the height he or she should be in adulthood and will remain short for the rest of his or her life.

Anabolic steroids affect the brain

The areas of the brain that influence our mood and involve learning and memory are called the limbic system. Anabolic steroids affect the limbic system.

In animals, steroids have been shown to impair learning and memory. They also cause mood changes such as depression and restlessness. Users of anabolic steroids may behave badly towards friends and family members whom they have always been nice to and whom they love. In the brain, it can initiate really aggressive behaviour. Some outbursts of anger can be quite serious, these have become known in the media as 'roid rages'.

Anabolic Steroids Confuse Brain and Body

The production of testosterone in your body is controlled by a group of cells in the inner and lower part of the brain called the hypothalamus. The hypothalamus also does many other things. It helps control appetite, blood pressure, mood, reproductive function.

Anabolic steroids can change the messages sent from the hypothalamus to the body. This can disrupt normal hormone function.

In men, anabolic steroids can interfere with normal testosterone production. They can act directly on the testicles and cause them to shrink. This results in a decrease in sperm count and reproductive function. It can also cause irreversible hair loss.

In girls, anabolic steroids can cause loss of the menstrual cycle by acting on both the hypothalamus and the reproductive organs. It can also cause loss of hair, body growth, facial hair growth and a thickening of the voice. All of these changes are irreversible.

Anabolic steroids in medicine

Doctors never prescribe anabolic steroids to young healthy people for muscle growth. But some people are prescribed anabolic steroids to treat certain types of anaemia or to stop the production of testosterone in certain diseases in men.

You may have heard that sometimes doctors prescribe steroids to reduce swelling. This is true, but they are corticosteroids, not anabolic steroids. Because corticosteroids do not build muscle like anabolic steroids do, people cannot abuse them.

Let's test our knowledge (True/False?)

1. Many people take steroids by smoking or inhaling them.

2. Anabolic steroids affect the hypothalamus and limbic region of the brain.

3. Anabolic steroids strengthen the immune system.

4. Anabolic steroids cause breast development in boys and breast reduction in girls.

Answers: 1.False 2.True
3.False 4.True

Research Continues

Scientists still don't know much about the effects of anabolic steroids on the brain. Maybe one day you will make the next big discovery. Until then, read on.

THE BRAIN'S RESPONSE TO STIMULI

Hello, in this episode we're going to explore some fascinating facts about stimulants. Some of this information has been recently discovered by scientists.

Have you eaten chocolate or drunk soda lately? If you have, you have probably taken a dose of stimulants (caffeine is also in coffee) into your body. If you eat or drink large amounts of caffeine, you may feel anxious, irritable or energised. This is because caffeine, like stimulants, changes the way your brain works. But caffeine is a mild example of a stimulant. Many other stimulants are much stronger and some are illegal and very dangerous. Some need to be prescribed by a doctor.

Strong stimulants include:

Cocaine: Derived from the leaves of the coca plant. This substance/drug is often in the form of a white powder that some people take through the nose into the airways.

Crack: A form of cocaine used in the form of cigarettes.

Amphetamine: Often called 'speed'. These pills are sometimes prescribed by doctors for medical problems.

Methamphetamine: A powerful form of amphetamine made into transparent crystals (called ice) or powder (known as crank) that can be smoked as a cigarette or injected.

Impaired Communication in the Brain

Cocaine and amphetamines change the way the brain works by altering the way nerve cells communicate. Nerve cells, known as "neurons", send messages to each other by releasing special chemical substances called "neurotransmitters". Neurotransmitters work by binding to special sites on neurons called "receptors".

One of the neurotransmitters affected by cocaine is known as "dopamine ". Dopamine is released from neurones in the limbic system. The limbic system is the area of the brain where pleasure is controlled. Normally, once dopamine binds to a receptor on a neurone and causes changes in the cell, it is pumped back to the neurone from which it was released. But cocaine blocks the so-called 'dopamine transporter' pump, after which dopamine accumulates in the space between neurons ( synapses).

The result: Dopamine continues to have an effect long after its effect is supposed to end. This is why the person who uses cocaine experiences a feeling of extra pleasure for a short time.

Cocaine can damage the functioning of the brain

Cocaine produces a feeling of pleasure for a while, but then damages the ability to feel pleasure. According to research, long-term cocaine use reduces the amount of dopamine or the number of dopamine receptors in the brain. When this happens, nerve cells need cocaine to communicate. Without the substance/drug, the brain cannot send enough dopamine to the receptors to create the feeling of pleasure. If a long-term cocaine or crack user stops taking the substance/drug, he/she has a very strong desire to take the substance again because he/she cannot feel pleasure without the substance/drug.

Cocaine constricts blood vessels

Cocaine causes the blood vessels in the body to narrow and the blood flow to be squeezed. This is a problem. This makes it harder for the heart to pump blood around the body (have you ever tried to squeeze into tight trousers, then you can understand how the heart has difficulty pumping blood through narrowed blood vessels). This is called 'fibrillation' and can be very dangerous because the blood supply to the body stops.

Many of the effects of cocaine on the heart are the result of its effect on the brain, the body's control centre.

Scientists Discover Answers Fortunately, scientists have found a way to copy the gene that controls the dopamine transporter. This process is called 'cloning'.

As scientists study the cloned transporters, they will learn more about how cocaine works and how to prevent these effects. This work may even lead to the discovery of a cure for cocaine addiction.

Scientists are currently trying to produce fake cocaine as a treatment method. This chemical substance will bind to the dopamine transporter like real cocaine, but it will not prevent the normal return of dopamine into the cell, it will bind to the transporter instead of cocaine and prevent the effects of real cocaine.

Research Continues

Scientists still don't know much about the effects of cocaine and amphetamines on the brain. Maybe one day you will make the next big discovery.

BRAIN RESPONSE TO INHALANTS (VOLATILE SUBSTANCES)

Hello, in this section, we will explore fascinating facts about inhalants. Some of this information has been recently discovered by scientists. Maybe you've never heard of inhalants, but you probably encounter them quite often. Hairspray, petrol, spray paint. These are all inhalants, and many more are produced every day.

Many inhalants have a strong odour. Why do we call these substances inhalants? Some people deliberately inhale their fumes/vapours. Why does a person do this? Because the chemicals in the vapour/smoke change the functioning of the brain and make you feel happy, even if only for a short time. But inhalants are also very harmful.

Inhalants are not removed/cleaned/excreted from the body by exhaling

Inhalant vapour/smoke often contains more than one chemical. Some are quickly eliminated from the body, while others are retained by fatty tissue in the brain and nervous system and remain there for a long time.

One of these fatty tissues is myelin. Myelin is the protective shell that surrounds many nerve cells (neurons) in the body. Nerve cells in the brain and spinal cord are the control centre of the body. They control everything we do and think by sending and receiving messages.

If you imagine nerve cells as the body's electrical wires, then you can think of myelin as the insulating rubber that protects the electrical wire. One of the problems with long-term inhalant users is that the chemicals break down the myelin, and if the myelin breaks down, the nerve cells are unable to transmit messages.

Beyond the Brain

One reason why scientists are interested in inhalants is that these chemicals affect the body in many ways. Some effects are due to changes in the brain, while other effects are due to direct effects on other parts of the body, such as the circulatory system.

Did you know that inhalants dilate blood vessels, allowing larger amounts of blood to pass through? Some inhalants can also increase the heart rate. This is a serious problem, especially in someone who has inhaled butane gas. Butane is also found in lighters. This substance sensitises the heart to chemicals that carry messages from the nervous system to the heart. This chemical is noradrenaline, which speeds up the heartbeat in stressful situations, such as when something suddenly frightens you. If the heart becomes hypersensitive to noradrenaline, a normal jolt of the heart can cause it to temporarily lose rhythm and stop pumping blood around the body. Some inhalant users die in this way. Inhalants can cause death by suffocation. This occurs when inhaled vapour/smoke replaces oxygen in the lungs and brain.

Changes in the brain

The damage caused by long-term use of inhalants is that the activity of nerve cells in some parts of the brain slows down or stops. This can occur in the frontal cortex , the area of the brain used to solve complex problems and plan ahead. Or, if the inhalant travels to the cerebellum, which controls movement and coordination, it can cause slowing or clumsiness in some people.

Studies have shown that inhalants also damage neurons in an area of the brain called the hippocampus . This damage occurs because the cells do not get enough oxygen. Because the hippocampus helps with memory functions, a person who repeatedly uses inhalants may lose the ability to learn new information, not remember familiar things, or have difficulty following a simple conversation.

Do you fill in the blanks?

Sometimes nerve cells damaged by inhalants can repair themselves. The blanks in the brain-related words below represent damaged neurones. See if you can repair them by filling in the blanks with complementary letters (hint: all words are in this leaflet).

- M...L. .

- . .RO.

- ..P...M.. S

Answers:

1) Myelin

2) Neuron

3) Hippocampus

- Research Continues

The truth is that scientists still do not know much about the effects of inhalants on the brain. As scientists learn more about how different inhalants affect the brain, they will be able to develop treatments to prevent damage caused by inhalants. Maybe one day you will make the next big discovery.

BRAIN RESPONSE TO HALLUCINOGENS

Hallucinogens, as you may have guessed, cause people to experience imaginary experiences that seem real. The word "hallucinate" comes from Latin and means "to wander in the mind".

It doesn't matter that some people refer to hallucinogens as "tripping". The illusions caused by hallucinogens can last for hours. Some of these illusions can feel really good, but other parts can feel really scary.

Hallucinogens strongly affect the brain by disrupting the functioning of our five senses and altering our orientation in time and space. People who use these substances a lot may have difficulty concentrating, communicating, or telling the difference between reality and illusion.

Where do hallucinogens come from/how are they obtained?

Some hallucinogens can be found in plants. Mescaline is found in a cactus called peyote. Some mushrooms, known as magic mushrooms, also have hallucinogenic effects. However, most hallucinogens are chemicals that are not found in nature.

The following are examples:

- LSD

- Amphetamine, a substance I discussed in detail in our section on stimulants, MDA

- A type of amphetamine called ecstasy; MDMA

- PCP (phencyclidine), often called angel dust.

How do hallucinogens affect your senses?

Your brain controls all of your senses (sight, hearing, smell, taste and feeling). How does the brain communicate with the rest of your body? Chemical messengers transmit information from one nerve cell to another nerve cell in the brain and body. Messages are constantly being sent back and forth at an incredible speed.

Nerve cells are called neurons and their chemical messengers are called neurotransmitters. When neurotransmitters bind to specific places on nerve cells (places called receptors), they cause changes in nerve cells. This communication system can be interrupted by chemicals such as hallucinogens, and as a result the way you feel/perceive the world around you changes.

A New Discovery MDMA AND MDA cause neurons to release a neurotransmitter called serotonin . Serotonin is important for many types of neurones, including cells that receive sensory information and cells that control sleep and emotions. This released serotonin can overactivate serotonin receptors. In animals, MDMA and MDA have been shown to destroy the nerve fibres of serotonin-containing neurons. This can be a big problem because serotonin neurons are important for many conditions such as sleep, mood and control of heart rate.
Scientists have recently found that damaged serotonin neurons can regrow fibres, but the fibres do not develop normally. The fibres can grow in areas of the brain where they do not normally grow, but not where they should be. The new growth pattern may cause changes in mood, learning or memory.

EFFECTS OF PCP ON THE BRAIN

PCP prevents the normal effects of a neurotransmitter called glutamate, which should occur when it binds to its receptors in the brain. It also disrupts the effects of other neurotransmitters. The effects of this substance have quite unpredictable characteristics. For example, it can make some people hallucinogenic and aggressive, while others are pacified and dazed. It has an addictive effect.

LSD THE MOST WIDELY USED HALLUCINOGEN

LSD produces its effects mainly through a type of serotonin receptor. Since serotonin is involved in many important functions, the use of LSD can also produce many effects. These include insomnia, tremors, increased heart rate and blood pressure. LSD users may experience sensations all at once (including severe tremors) and their senses may appear to be confused (such as hearing colours and seeing sounds).

Even very small amounts of LSD can trigger these effects. And LSD has an unusual "echo". Many users experience flashbacks (sudden repetitions of their experiences with LSD) days after they stop using the substance.

Research Continues The truth is that there is still a huge gap in scientists' knowledge of the effects of hallucinogens on the brain. Maybe one day you will make the next big discovery.

THE BRAIN'S RESPONSE TO METHAMPHETAMINE

Hello, in this episode we will explore many fascinating facts about the stimulant drug methamphetamine. Some of these facts have only recently been discovered by leading scientists.

Speed, meth, chalk, ice, glass - all of these names are used for methamphetamine. Methamphetamine is produced in many different forms and can be snorted, ingested, injected with a needle or smoked.

Methamphetamine is a powerful drug. It works by changing the way the brain works. It also speeds up most bodily functions. Methamphetamine has a chemical structure similar to another substance called amphetamine. Methamphetamine can cause many damaging conditions such as difficulty sleeping, paranoia, aggression and hallucinations.

How does methamphetamine work/how do its effects manifest?

Regardless of how methamphetamine is used, it quickly enters the bloodstream to the brain. Methamphetamine can affect most brain structures, but it primarily affects areas that contain the chemical dopamine . This is because methamphetamine is similar in shape, size and chemical structure to dopamine. Before I say more about dopamine and methamphetamine, I will explain how nerve cells work.

Your brain is made up of billions of nerve cells, also called neurons. Neurons come in different shapes and sizes, but most contain three important parts: a cell body, which contains the nucleus and governs the neuron's activities; dendrites, which are short filamentous extensions that receive messages from other neurons and relay them to the cell body; and the axon, a single extension that carries messages from the cell body to the dendrites of other neurons.

The axons of one neuron and the dendrites of a neighbouring neuron are located very close to each other, but there is no actual contact between them. They therefore use chemical messengers called neurotransmitters to communicate with each other. When one neuron wants to send a message to another, it releases a neurotransmitter from its axon into the narrow space between the two neurons. This space in between is called the synapse. The neurotransmitter crosses the synapse and binds to a specific site on the dendrite of the neighbouring neuron, called a receptor. Once the neurotransmitter has delivered its message, it is either eliminated or returned to the first neuron where it is utilised for reuse.

There are many different neurotransmitters, but dopamine is the most affected by dopamine. Dopamine is sometimes called the pleasure neurotransmitter because it helps you feel good by doing things like playing football, eating a big piece of chocolate cake or riding a roller coaster.

When something that gives you pleasure happens, certain neurones release large amounts of dopamine. Dopamine binds to receptors on the dendrites of neighbouring neurons and relays the pleasurable message. This process ends when the dopamine is released from the receptors and returned to the neuron from which it was released for future reuse.

Methamphetamine has many other effects

Because it is similar to dopamine, methamphetamine can alter the functions of any neurone containing dopamine . And if that wasn't enough, methamphetamine can also affect neurones containing two other neurotransmitters, norepinephrine and serotonin . All of this shows how methamphetamine can change so much about how the brain and body function. Even just a small amount of methamphetamine can cause a person to become more alert and more active, lose cravings and become more irritable and aggressive. It also increases blood pressure and speeds up heart beats.

Methamphetamine Changes the Brain

Usually neurons reprocess dopamine. But methamphetamine can trick neurons into thinking that it is dopamine. Once in a neuron, methamphetamine causes that neuron to release large amounts of dopamine. All this dopamine leads to a feeling of extreme well-being that can last all day long. Eventually, however, these pleasurable effects end and unpleasant feelings called "crashes" occur, which often cause the person to take more of the drug. If a person continues to take methamphetamine, they will experience a difficult period in which they will not enjoy anything. Imagine no longer enjoying your favourite food or an afternoon with friends...

What Happens If a Person Uses Methamphetamine for a Long Time?

Scientists use some imaging techniques, such as positron emission tomography (PET), to study the brains of people who use methamphetamine. They have found that long-term methamphetamine users still have damaged dopamine neurons three years after stopping methamphetamine.

Scientists do not yet know whether this damage is permanent, but this research shows that the brain changes caused by methamphetamine use persist for at least a long time. Animal research shows that methamphetamine also damages neurones containing serotonin . This damage also persists for a long time after discontinuation of use. These changes in dopamine and serotonin neurones may explain some of the effects of methamphetamine. If a person uses methamphetamine for a long time, they may become paranoid. They may start to see and hear things that are not there. These are called hallucinations (hallucinations). Because methamphetamine causes a significant increase in blood pressure, some long-term users may have permanent damage to the blood vessels in the brain. This can lead to strokes resulting from brain haemorrhages.

BRAIN RESPONSE TO OPIATES

In this section we will give you information about opiates. If you have seen "The Wizard of Oz", you will have seen the poppy plant, which is the source of a type of substance called opiates. When Dorothy lies down in a poppy field, she falls into a deep sleep. No wonder the Latin name of the plant -Papaver somniferum- means "poppy makes you sleepy".

Opiates are made from opium extracted from the poppy plant. They are also called narcotics. You may have heard of heroin, morphine or codeine. These are examples of opiates.

Opiates quickly give an intense feeling of pleasure followed by a feeling of well-being and a calm drowsiness. But this is also an addictive substance. If someone uses opiates over and over again, their brain becomes addicted to the substance.

Nerve cells experience addiction and withdrawal

Long-term opiate use changes the functioning of nerve cells in the brain. These cells develop and need opiates even to function normally. If opiates are removed from the addicted cells, many of the cells will become overactive. Eventually these cells start to function normally again, but in the meantime they cause a number of symptoms in the brain and body. These are called withdrawal/deprivation symptoms.

Have you ever caught a cold? You have probably experienced symptoms such as headache, fever, sweating, chills or shivering. These are similar to withdrawal symptoms, but the withdrawal symptoms are worse.

Ø Here is a way to show how difficult it is for brain cells to function without the substance they are addicted to : Take a piece of paper and try to draw your name not with your usual hand, but with the other one.

Opiates affect many parts of the brain and nervous system

The limbic system controls emotions. Opiates alter the limbic system to produce more feelings of pleasure, relaxation and relaxation.

The brain stem controls the functions your body performs automatically, such as breathing or coughing. Opiates can act on the brain stem to stop coughing or slow breathing.

The spinal cord carries pain impulses from the body. By acting here, opiates block pain messages and enable people to tolerate even serious injuries.

How Nerve Cells Respond to Opiates

In the limbic system, brainstem and spinal cord there are areas where certain nerve cells recognise opiates. When stimulated by opiates, these areas - called opiate receptors - trigger responses in the brain and body.

Scientists have identified three types of opiate receptors: delta, mu and kappa (named after letters in the Greek alphabet). Each of these receptors is involved in different brain functions. For example, the mu receptor is responsible for the pain-relieving effect of morphine.

Cloning Receptors

After many years of experiments, scientists have discovered how to copy the genes that control the production of opiate receptors. This makes it easier for researchers to make opiate receptors and to study how opiates affect nerve cells.

This discovery could lead to other exciting developments, such as better treatment of opiate addiction.

Opiates Stop Pain

Did you know that some opiates have important medical uses? They are powerful painkillers and doctors sometimes prescribe them to treat diarrhoea. If you look at the label of a cough medicine you will see that one of the ingredients is codeine.

When used appropriately for medical purposes, opiates do not produce intense feelings of pleasure and patients have only a very small risk of developing addiction.

Surprising Facts

Your brain produces its own opiates called endogenous/intrinsic opioids. These chemicals bind to opiate receptors and act just like opiates.

Endogenous opiates are your body's way of controlling pain. If you have ever felt a pleasant relaxation when you exercise too much, this is probably due to the natural chemicals released in your brain.

Research Continues

The fact is that there is still a huge gap in scientists' knowledge of the effects of opiates on the brain.

BRAIN RESPONSE TO NICOTINE

For centuries people have chewed or smoked tobacco from the plant Nicotiana tabacum . Tobacco is used by many people because it contains a powerful substance known as nicotine.

When tobacco is smoked, nicotine is absorbed by the lungs and is quickly absorbed into the bloodstream circulating to the brain. All this happens very quickly. In fact, nicotine reaches the brain within 8 seconds after smoking tobacco. Nicotine can also enter the bloodstream through the mucous membranes in the mouth (if tobacco is chewed) or nose (if snorted) or even through the skin.

Nicotine affects the whole body. It acts directly on the heart, changing the heart rate and blood pressure. It also affects the nerves that control respiration and changes the breathing pattern. In high concentrations nicotine is lethal, in fact a single drop of pure nicotine in the mouth will kill a person. Because it is highly lethal, it has been used as an insecticide for centuries.

So why do people smoke?

Because nicotine stimulates the pleasure areas in the brain.

How does nicotine work in the brain?

Your brain is made of billions of nerve cells. Nerve cells communicate by releasing messengers called neurotransmitters. Each neurotransmitter is like a key that fits into structures called receptors, which we can describe as a special "lock" on the surface of nerve cells. When a neurotransmitter finds its lock, it activates the nerve cell of the receptor.

The nicotine molecule has a structure similar to a neurotransmitter called acetylcholine . Acetylcholine and its receptors are involved in many functions such as muscle movement, respiration, heart rate, learning and memory. It also causes the release of other neurotransmitters and hormones that affect mood, cravings, memory and much more. When nicotine reaches the brain, it binds to acetylcholine receptors and mimics the effects of acetylcholine.

Nicotine also activates the pleasure and reward centres in the brain. Scientists have recently discovered that nicotine increases the levels of a neurotransmitter called dopamine in the pleasure and reward centres of the brain. Sometimes referred to as the pleasure molecule, dopamine is a neurotransmitter that is also involved in addiction to other substances such as cocaine and heroin. Researchers now believe that this change in dopamine may play a key role in all addictions. This may help explain why people find it so difficult to quit smoking.

Easy to Start, Hard to Quit

Did you know that nicotine is as addictive as cocaine or heroin? If a person uses nicotine over and over again through smoking or chewing tobacco, his or her body develops a tolerance to it. Eventually the person becomes addicted. Once a person is addicted, it is extremely difficult to quit. People who started smoking before the age of 21 have the hardest time quitting and only 1 in 10 people who try to quit smoking succeed.

When nicotine addicts stop smoking, they experience restlessness, hunger, depression, headaches and many other unpleasant feelings. These are called "withdrawal symptoms" because they occur when nicotine is withdrawn from the body. Withdrawal can be bad, but long-term smoking is much worse. It raises your blood pressure, dulls your sense of taste and smell, reduces your strength and causes wrinkles in your skin. More dangerously, long-term smoking can cause fatal heart attacks, strokes, emphysema and cancer.

You may be surprised to learn that tobacco use causes more fatal diseases than any other addictive substance. In the United States, one in six deaths is caused by smoking. But even when faced with the risk of death, most people continue to smoke because they are so addicted to nicotine. Believe it or not, half of all smokers who have a heart attack continue to smoke despite warnings from their doctor. A very strong addiction!

Smokeless tobacco also has damaging effects. Chewing tobacco can lead to damage to the gum tissue and even loss of teeth. Most importantly, smokeless tobacco contains carcinogenic chemicals that can cause cancers of the mouth, pharynx, larynx and oesophagus. This can occur even in very young users. In fact, most people who develop these cancers are chewing tobacco users.

Match The brain's best defence against tobacco use is to think very carefully before using it. Start by trying to match the correct percentages to the following situations:

- Percentage of smokers who started smoking in their teens

- Percentage of users aged 17 or younger who say they are sorry they started smoking

- Proportion of young smokers who continue to smoke and die from smoking-related diseases

A. Approximately 30

B. %80-%90

C. %70

(Answers: 1-B, 2-C, 3-A)

ALCOHOLISM and PREGNANCY

- Alcoholism Can Hurt Your Baby When You Are Pregnant

When you are pregnant, your baby grows inside you. Everything you eat and drink while you are pregnant affects your baby. If you drink alcohol, this can harm your baby's growth. Your baby may have physical and behavioural problems that can last for the rest of its life. Children born with many serious alcohol-related problems are called foetal alcohol syndrome .

Babies with foetal alcohol syndrome can have the following:

1. They are born small

2. Eating and sleep problems

3. Hearing and visual impairments

4. Difficulty following instructions and learning to do simple things

5. Learning and attention difficulties at school

6. Need for special teachers and schools

7. Difficulty getting along with other people and controlling their behaviour

8. The need for medical care throughout their entire life

Ø Below are some questions and answers about alcohol use and alcoholism during pregnancy

1. Can I drink/use alcohol while pregnant?

No, you may not. Never drink alcohol while you are pregnant. Because every time you drink alcohol, your baby drinks with you. Think about it. Everything you drink, your baby drinks too.

2. Is there a safe type of alcohol to drink during pregnancy?

No, there is not. Any alcoholic drink you drink while you are pregnant can harm your baby. Alcoholic drinks are beer, wine, liqueurs or cocktails. A glass of wine, a can of beer or a glass of cocktail all contain about the same amount of alcohol.

3. What should I do if I drank alcohol during my last pregnancy and my baby is healthy?

Every pregnancy is different. Drinking alcohol can harm one baby more than another. One of your babies may be born completely healthy, while the other baby may be born with many problems.

4. Will these problems go away / get better?

No, they will not. These problems will continue for the rest of your child's life. People with serious problems may not become adults who can look after themselves. They may never be able to work.

5. What should I do if I became pregnant while continuing to drink?

If you were drinking alcohol before you found out you were pregnant, stop drinking now. You will feel better and give your baby another chance to be born healthy. Do not drink alcohol if you are planning to become pregnant. You will not know immediately whether you are pregnant or not. Alcohol can harm your baby even in the first or second month of pregnancy.

6. How can I stop drinking?

There are many ways to stop drinking on your own. You do not have to drink when other people are drinking. If someone offers you a drink, just say 'no'. Avoid people and places that make you drink alcohol. Do not keep alcohol at home.

§ If you cannot stop drinking, get help. You may have a disease called alcoholism . There are programmes that can help you to stop drinking. These are called alcohol treatment programmes . Your doctor can find a programme to help you. Even if you have already been in a treatment programme, try again. There are programmes for women only.