What happens to your brain if you keep taking drugs?

Just as we turn down the volume on a radio that is too loud, the brain adjusts to the overwhelming surges in dopamine (and other neurotransmitters) by producing less dopamine or by reducing the number of receptors that can receive signals.

As a result, dopamine’s impact on the reward circuit of a drug abuser’s brain can become abnormally low, and the ability to experience any pleasure is reduced. This is why the abuser eventually feels flat, lifeless, and depressed, and is unable to enjoy things that previously brought them pleasure. Now, they need to take drugs just to try and bring their dopamine function back up to normal. And, they must take larger amounts of the drug than they first did to create the dopamine high – an effect known as tolerance.


Decreased Dopamine Transporters in a Methamphetamine Abuser

brain scan

Methamphetamine abusers have significant reductions in dopamine transporters.
Source: Am J Psychiatry 158:377–382, 2001.


We know that the same sort of mechanisms involved in the development of tolerance can eventually lead to profound changes in neurons and brain circuits, with the potential to severely compromise the long-term health of the brain. For example, glutamate is another neurotransmitter that influences the reward circuit and the ability to learn.

When the optimal concentration of glutamate is altered by drug abuse, the brain attempts to compensate for this change, which can cause impairment in cognitive function. Similarly, long-term drug abuse can trigger adaptations in habit or no conscious memory systems. Conditioning is one example of this type of learning, whereby environmental cues become associated with the drug experience and can trigger uncontrollable cravings if the individual is later exposed to these cues, even without the drug itself being available. This learned “reflex” is extremely robust and can emerge even after many years of abstinence

Chronic exposure to drugs of abuse disrupts the way critical brain structures interact to control and inhibit behaviours related to drug abuse. Just as continued abuse may lead to tolerance or the need for higher drug dosages to produce an effect, it may also lead to addiction, which can drive an abuser to seek out and take drugs compulsively. Drug addiction erodes a person’s self-control and ability to make sound decisions, while sending intense impulses to take drugs.


How does the brain communicate?

The brain is a communications centre consisting of billions of neurons, or nerve cells. Networks of neurons pass messages back and forth to different structures within the brain, the spinal column, and the peripheral nervous system. These nerve networks coordinate and regulate everything we feel, think, and do.

  • Neuron to Neuron
    Each nerve cell in the brain sends and receives messages in the form of electrical impulses. Once a cell receives and processes a message, it sends it on to other neurons.
  • Neurotransmitters – The Brain’s Chemical Messengers
    The messages are carried between neurons by chemicals called neurotransmitters. (They transmit messages between neurons.)
  • Receptors – The Brain’s Chemical Receivers
    The neurotransmitter attaches to a specialized site on the receiving cell called a receptor. A neurotransmitter and its receptor operate like a “key and lock,” an exquisitely specific mechanism that ensures that each receptor will forward the appropriate message only after interacting with the right kind of neurotransmitter.
  • Transporters – The Brain’s Chemical Recyclers
    Located on the cell that releases the neurotransmitter, transporters recycle these neurotransmitters (i.e., bringing them back into the cell that released them), thereby shutting off the signal between neurons.

To send a message a brain cell releases a chemical (neurotransmitter) into the space separating two cells called the synapse. The neurotransmitter crosses the synapse and attaches to proteins (receptors) on the receiving brain cell. This causes changes in the receiving brain cell and the message is delivered.

Most drugs of abuse target the brain’s reward system by flooding the circuit with dopamine.

Introducing the Human Brain

The human brain is the most complex organ in the body.

This three-pound mass of gray and white matter sits at the centre of all human activity – you need it to drive a car, to enjoy a meal, to breathe, to create an artistic masterpiece, and to enjoy everyday activities. In brief, the brain regulates your basic body functions; enables you to interpret and respond to everything you experience; and shapes your thoughts, emotions, and behaviour.

The brain is made up of many parts that all work together as a team. Different parts of the brain are responsible for coordinating and performing specific functions. Drugs can alter important brain areas that are necessary for life-sustaining functions and can drive the compulsive drug abuse that marks addiction.

Brain areas that are affected by drug abuse –

  • The brain stem controls basic functions critical to life, such as heart rate, breathing, and sleeping.
  • The limbic system contains the brain’s reward circuit – it links together a number of brain structures that control and regulate our ability to feel pleasure. Feeling pleasure motivates us to repeat behaviours such as eating – actions that are critical to our existence. The limbic system is activated when we perform these activities – and also by drugs of abuse. In addition, the limbic system is responsible for our perception of other emotions, both positive and negative, which explains the mood-altering properties of many drugs.
  • The cerebral cortex is divided into areas that control specific functions. Different areas process information from our senses, enabling us to see, feel, hear, and taste. The front part of the cortex, the frontal cortex or forebrain, is the thinking centre of the brain; it powers our ability to think, plan, solve problems, and make decisions.



Drugs, Brains, and Behaviour: The Science of Addiction

As a result of scientific research, we know that addiction is a disease that affects both brain and behaviour. Drugs are chemicals. They work in the brain by tapping into the brain’s  communication system and interfering with the way nerve cells normally send, receive, and process information.

Some drugs, such as marijuana and heroin, can activate neurons because their chemical structure mimics that of a natural neurotransmitter. This similarity in structure “fools” receptors and allows the drugs to lock onto and activate the nerve cells.

Although these drugs mimic brain chemicals, they don’t activate nerve cells in the same way as a natural neurotransmitter, and they lead to abnormal messages being transmitted through the network.

Other drugs, such as amphetamine or cocaine, can cause the nerve cells to release abnormally large amounts of natural neurotransmitters or prevent the normal recycling of these brain chemicals.

This disruption produces a greatly amplified message, ultimately disrupting communication channels. The difference in effect can be described as the difference between someone whispering into your ear and someone shouting into a microphone.

When some drugs of abuse are taken, they can release 2 to 10 times the amount of dopamine that natural rewards do.

In some cases, this occurs almost immediately (as when drugs are smoked or injected), and the effects can last much longer than those produced by natural rewards. The resulting effects on the brain’s pleasure circuit dwarfs those produced by naturally rewarding behaviours such as eating and sex.

The effect of such a powerful reward strongly motivates people to take drugs again and again. This is why scientists sometimes say that drug abuse is something we learn to do very, very well.

7 Must Eat Foods For The Brain

The foods that will supercharge your brain are called foods for your brain. Simply put, your brain likes to eat.

And it likes powerful fuel: quality fats, antioxidants, and small, steady amounts of the best carbs.

The following foods are called main foods for your brain:-

 1. Avocado

Start each day with a mix of high-quality protein and beneficial fats to build the foundation for an energized day. Avocado with scrambled eggs provides both, and the monounsaturated fat helps blood circulate better, which is essential for optimal brain function – and it’s possible the avocado’s plentiful antioxidants help combat diseases like diabetes .

2.     Blueberries

These delicious berries are one of the best foods for you, period, but they’re very good for your brain as well. Since they’re high in fiber and low on the glycemic index, they are safe for diabetics and they do not spike blood sugar. Blueberries are possibly the best brain food on earth: they have been linked to reduced risk for Alzheimer’s, shown to improve both memory and learning ability (and motor skills in rats), and they are one of the most powerful anti-stress foods you can eat. Avoid: dried, sweetened blueberries.

 3.     Wild Salmon

Omega-3 fatty acids are essential for your brain. These beneficial fats are linked to improved cognition and alertness, reduced risk of degenerative mental disease (such as dementia), improved memory, improved mood, and reduced depression, anxiety, hyperactivity and cardiovascular disfunction.

4.     Nuts

Nuts contain protein, high amounts of fiber, and they are rich in beneficial fats. For getting an immediate energy boost that won’t turn into a spike later, you can’t do better than nuts. The complex carbs will perk you up while the fat and protein will sustain you. Nuts also contain plenty of vitamin E, which is essential to cognitive function.

5.     Seeds

Seeds contain a lot of protein, beneficial fat, and vitamin E, as well as stress-fighting antioxidants and important brain-boosting minerals like magnesium. Sesame seeds in particular are a real Swiss Army Knife of health benefits.

6. Coffee

Coffee is good for your brain. Did you know coffee actually contains fiber? That’s going to help your cardiovascular system. Coffee also exerts some noted benefit to your brain in addition to providing you with a detectable energy boost (note: it’s not as simple as boosting your brain-power, but it can make you work more effectively, depending on the work you’re doing). There is also evidence that it may provide an electrical jolt to backwater parts of your brain as well as potentially strengthening synapses associated with learning and special memory.

7.     Oatmeal

Nature’s scrub brush is one of the best foods for cardiovascular health, which translates to brain health.

8.     Beans

One more for carb-lovers. (The brain uses about 20% of your carbohydrate intake and it likes a consistent supply). Beans are truly an amazing food that is sadly overlooked. They’re humble, but very smart. Not only are they loaded with fiber, vitamins, minerals and protein, they’re ridiculously cheap. An entire bag of beans usually costs only a few dollars and will provide many meals. Beans provide a steady, slow release of glucose to your brain – which means energy all day without the sugar crash.

7.     Brown Rice

Brown rice is a low-glycemic complex carbohydrate that is excellent for people sensitive to gluten who still want to maintain cardiovascular health. The better your circulation, the sharper your brain – and as part of a campaign to get the Philippines to switch from white to brown rice, it’s been claimed that brown rice can boost your memory.

In spite of above mentioned  tea,chocolate,oysters,olive oil and tuna are called important foods for your brain also.

If you want to learn more about the benefits of foods for your brain, check out the book Train Your Brain: Your Food Matters on Amazon.

Chris Hughes

Chris is an Internet Entrepreneur, Juggler, Traveler and loves learning. Chris is out to enjoy life while building profitable businesses that allow people to have more fun in their lives.

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