HOW DOES MARIJUANA AFFECT THE BRAIN?

Biology 202
2004 First Web Paper
On Serendip

HOW DOES MARIJUANA AFFECT THE BRAIN?

AKUDO EJELONU

Pot, weed, grass, ganja and skunk, are some of the common words used to describe the dried leaves drug known as marijuana. Marijuana is a cannabis plant that is "usually smoked or eaten to entice euphoria." (1). Throughout the years, there has been research on the negative and positive effects of marijuana on the human body and the brain. Marijuana is frequently beneficial to the treatment of AIDS, cancer, glaucoma, multiple sclerosis, and chronic pain. However, researchers such as Jacques-Joseph Moreau have been working to explain how marijuana has harmful affects on the functions of central nervous system and hinders the memory and movement of the user's brain. The focus of my web paper is how the chemicals in marijuana, specifically cannabinoids and THC have an effect on the memory and emotions of a person's central nervous system.

Marijuana impinges on the central nervous system by attaching to brain's neurons and interfering with normal communication between the neurons. These nerves respond by altering their initial behavior. For example, if a nerve is suppose to assist one in retrieving short-term memory, cannabinoids receptors make them do the opposite. So if one has to remember what he did five minutes ago, after smoking a high dose of marijuana, he has trouble. Marijuana plant contains 400 chemicals and 60 of them are cannabinoids, which are psychoactive compounds that are produced inside the body after cannabis is metabolized or is extorted from the cannabis plant. Cannabinoids is an active ingredient of marijuana. The most psychoactive cannabinoids chemical in marijuana that has the biggest impact on the brain is tetrahydrocannibol, or THC. THC is the main active ingredient in marijuana because it affects the brain by binding to and activating specific receptors, known as cannabinoid receptors. "These receptors control memory, thought, concentration, time and depth, and coordinated movement. THC also affects the production, release or re-uptake (a regulating mechanism) of various neurotransmitters."(2) Neurotransmitters are chemical messenger molecules that carry signals between neurons. Some of these affects are personality disturbances, depression and chronic anxiety. Psychiatrists who treat schizophrenic patient advice them to not use this drug because marijuana can trigger severe mental disturbances and cause a relapse.

When one's memory is affected by high dose of marijuana, short-term memory is the first to be triggered. Marijuana's damage to short-term memory occurs because THC alters the way in which information is processed by the hippocampus, a brain area responsible for memory formation. "One region of the brain that contains a lot of THC receptors is the hippocampus, which processes memory."(3) Hippocampus is the part of the brain that is important for memory, learning, and the integration of sensory experiences with emotions and motivation. It also converts information into short-term memory. "Because it is a steroid, THC acts on the hippocampus and inhibits memory retrieval."(4) THC also alters the way in which sensory information is interpreted. "When THC attaches to receptors in the hippocampus, it weakness the short-term memory,"(5) and damages the nerve cells by creating structural changes to the hippocampus region of the brain. When a user has a high dose of marijuana, new information does not register into their brain and this may be lost from memory and they are not able to retrieve new information for more than a few minutes. There is also a decrease in the activity of nerve cells.

There are two types of memory behavior that is affected by marijuana, recognition memory and free cells. Recognition memory is the ability to recognize correct words. Users can usually recognize words that they previous saw before smoking but claim to recognize words that they did not previously see before smoking. This mistake is known as memory intrusions. Memory intrusions are also the consequence of THC affecting the free cell of the brain. "Marijuana disrupts the ability to freely recall words from a list that has been presented to an intoxicated subject."(6) For example, if a list of vocabulary words presented to the intoxicated subject and few minutes later, they have to recall the words that were on the list. The only words that they remember are the last group of words and not the words that are in the beginning of the list. This is an initiation that their memory storage has been affected. "The absence of an effect at short term delay times indicates that cannabinodis did not impair the ability to perform the basic task, but instead produce a selective learning and/or memory deficit."(7) I did a study with two college students (Student A and Student B) who both smoke marijuana every other week. This particular study was done an hour before, while and after they were under the influence of the drug. Student A was watching television before she smoked marijuana, was asked which advertisement was splayed before the show started and she got four out of five of her answers correct. After this first section, she smoked a small dose of marijuana twice within an hour. Fifteen minutes after she smoked her last blunt, she continued her regular activity of watching sitcoms. When a commercial would come on, I would ask her simple questions like what happened before the show went to a commercial break. Her responses would be macro-answers about what was going on but when I asked her what the main character was wearing, she did not remember. This was ironic because the protagonist wore a bright yellow suit that my friend commenting on earlier when the show began ten minutes ago. Her short-term memory is weakening because she was only able to remember big picture information and not small picture. Though the results are interesting, I know that I would have had different response on someone else because it depends on how often the user smokes and if they have good memory prior to smoking weed.

Marijuana also impairs emotions. When smoking marijuana, the user may have uncontrollable laughter one minute and paranoia the next. This instant change in emotions has to do with the way that THC affects the brain's limbic system. The limbic system is another region of the brain that governs one's behavior and emotions. It also "coordinates activities between the visceral base-brain and the rest of the nervous system."(8) I am now going to use Students B to describe how emotions are affected by marijuana. Students B is an articulate and well spoken young woman who has a troublesome relationship with her best friends which gets her upset and tense up. But after she smoked one high dose weed, her body was relaxed however, she had trouble formulating her thoughts clearly and would talk in pieces and was jubilant. It has been researched that a person needs to have high dose of marijuana would be in the state of euphoria. High dose of marijuana is measured as "15mg of THC can cause increased heart rate, gross motor disturbances, and can lead to panic attacks."(9) Thankfully, Student A did not experience any of these extreme examples.

College students usually smoke marijuana because they are stressed over schoolwork and feel that marijuana can help them unwind. I have encountered marijuana smokers who are chilled and have no worries in the world but after the effect of the drug wears off, they're sometimes capable to tacking their problem or at the original state that they were in before the drug. The effects of happiness that marijuana usually cause to the user is not a lasting effect because even though a user smokes weed to get away from the troubles of his/her own life, they still have to face these problems after the effects of the drug wears-off. In a survey with college student, an organization called, parents: the Anti-Drug interviewed college students and found that "compared to the light users, heavy marijuana users made more errors and had more difficulty sustaining attention."(10) This was evident through my second experiment with Student B but not everyone who smoke high doses of marijuana experience the same affect.

The chemicals in marijuana bring cognitive impairment and troubles with learning for the user. "Smoking [marijuana] causes some changes in the brain that are like those caused but cocaine, heroin, and alcohol. Some researchers believe that has changes may put a person more at risk of becoming addicted to other drugs such a cocaine and heroin."(11) To prevent such harm, one must be cautious of their actions. Those who do not do drugs do not risk harm. So please the next day you light up, remember you that you central nervous system and brain will be at risk.

1)Online Dictionary

2)Marijuana: The Brain's Response to Drugs, A Good Web Source

3)Mind Over Matter: Marijuana Series, A Good Web Source

4)Alcohol Addiction & The Limbic System, A Good Web Source

5)Marijuana: The Brain's Response to Drugs, A Good Web Source

6)Cellular and Molecular Mechanisms Underlying Learning and Memory Impairments Produced by Cannabinoids, A Good Web Source

7)Cellular and Molecular Mechanisms Underlying Learning and Memory Impairments Produced by Cannabinoids, A Good Web Source

8)Marijuana and the Brain by John Gettman. High Times, March, 1995, A Good Web Source

9)Alcohol Addiction & The Limbic System, A Good Web Source

10)Parents. The Anti-Drug. -- Drug Information, A Good Web Source

11)Marijuana: Marijuana Brain Effects, A Good Web Source

 

 

Comments made prior to 2007

I smoked pot straight now since I was 13 years old Im 25 now I smoke it everyday literally through a Bong. I do not smoke well im at work but as soon as im off and for the remainder of the evening till I end up going to bed I do smoke. Now I read your page about the effects pot has on short term memory and brain function, Since I started smoking pot my asthma has vanished my grades went up in school my mind learns at quicker rates and my short term memory is far from gone There isnt much I forget about, unless it is because of my selective memory. Were the people that you tested on already marijuana smokers and also there are diff things to be taken into consideration when testing a substance for example the way it was grown marijuana has to be grown with nutrients and fertalizers to become potent enough to smoke for a high but when people use these fertilizers and such they sometimes do not leech the foods out from the plants which could lead to all kinds of bad side effects Im wondering if this kind of inforamtion is taken into consideration when giving test subjects marijuana to smoke or ingest.

I have no side effects other than a burnt out feeling after smoking all nite, and in teh morning of course but no brain problems like teh ones your website describes ... Chris, 7 July 2006

 

 

Yeah...i disagree on a lot of things that you have to say about this. Like for one some of the things you mentioned only happen while you're high, but after the high goes away those things do as well. Marijuana is not addicting like other hard drugs or alcohol. Also marijuana helps people with ADD, makes them focus better, and sometimes learn better. Sometimes when you smoke your nerves are more dull, but sometimes they can be more alive, so to speak. You need to know that everybody reacts to marijuana differently. So these test that your doing don't go for everybody. You need to let people know that or else thats kind of false information. Something that really got to me is when you were talking about how people do it to relax and get their mind of things and once the highs gone all the problems come back. Well once again everybody reacts differently to marijuana. A lot of people when there high talk a lot about there problems and life in general. What I'm getting at here is that while their high they can figure out there problems because being high brings you into a new type of world and you think about everything more carefully. It's like it opens up your brain and lets you think more into your thoughts and about whats going on. A lot of times they can solve their problems like that, especially when there is someone there with them to talk to. Marijuana also brings people together. I know someone who hated a bunch of people, but then one day ended up smoking with them. Next thing she knew, they were all the best of friends. I know a group of people and within that group you've got your "gangster" type, Punk type, goth type, preppy type, hick type, and the list just keeps going. All of them probably wouldn't even talk if it wasn't for marijuana bringing them together. I have a lot more to say but, I'm not going to because I have pretty much proved my point. Also marijuana brings the creativeness out in people. Some of the greatest authors, poets, music artist, painters, and so on, get their great ideas or create there masterpieces by being high.

 

P.S I would also like to add that I am a chronic user and I could remember your whole entire report on it. I also have excellent grades in school, in fact better than when I didn't smoke. I also would just like to add one more thing: You will not understand or ever be able to know how or what marijuana does to you unless you do it yourself. Trust me I once was all anti-marijuana and always said that it does all these bad things to you and blah blah blah. Well now I actually know how it really does make people feel because I have experienced it and everything there is in that type of world.

 

P.S.S I do agree with a few things that you had to say ... Jen, 9 November 2006

 

 

Hi, I really found this information very useful because it IS a misconvention among most of the college/university goers that marijuana increases concentration and increases the work capacity of an individual. I personally believe that it DOES increase the work capacity of the abuser to some extent, that's when the drug abuser is not in a "stoned" state of mind, but then too, what is at stake is the brain and central nervous system malfunctioning, which degrades the intellectual, job and social skills. So in my opinion, it's not a good deal ... Ankur Gupta, 25 February 2007

 

 

allright tell me something if you say a list of say 20-30 vocabulary words and you were asked to read them over, then you were asked say 5 minutes later to remember as many of those words as you can, do you really think you'll be able to do that? no i bet if you asked 100 people to do that that around 90% of them wouldnt be able to do it.

 

also riddle me this batman, how many people die each year from drunk driving accidents? now dont im pretty sure you've been drunk, and maybe once smoked pot in your life right? well which had a more sever affect the weed or the alcohol? yeah the alcohol!

 

im a stoner i will proudly say that. but if i have the choice between alcohol and weed i'd take weed anyday. i've driven high that isnt a problem. when im high i drive a little slower then normal and im lookin for the nearest 7-11.

 

weed isnt a drug it has no addictive characteristics what so ever!!! ciggaretes kill more people then alchol,guns,and pissed off husbands who come home early.

 

now weed doesnt lead to other drugs what so ever, i've been smokin the stuff everyday for the past 4 years and i have yet to even think about trying other drugs. if mother nature didnt want us to smoke it she wouldnt have put it here!

 

its as simple as that!! ... Reader on the web, 21 July 2007

 

 

Hello, I was told about this site as a friend of mine was completing a research paper. As I looked over it, there seems to be lots of misinformation involved, and my friend has abandoned this site. I wouldn't mind if you read through all of my message carefully. To start off, the following statement is not backed by any scientific evidence what so ever. "Marijuana impinges on the central nervous system by attaching to brain's neurons and interfering with normal communication between the neurons." This has been proven to be false on multiple occasions since the 1970's. Cannabinoids to not not impinge on the nervous system what so ever, this isn't lysergic acid we're dealing with. "Marijuana plant contains 400 chemicals and 60 of them are cannabinoids" This quote right here is misleading. Every plant is comprised of hundreds of chemicals. In fact, they're not even chemicals, they're just substances that comprise the plants' structure. Also, the majority of cannabinoids that are also found in cannabis are produced by the body naturally. Also regarding cannabinoid receptors. "These receptors control memory, thought, concentration, time and depth, and coordinated movement. THC also affects the production, release or re-uptake (a regulating mechanism) of various neurotransmitters." This is simply false, I do not know where this source came from. Your brain does not use cannabinoid receptors for memory, thought, or concentration. Next,saying that "When one's memory is affected by high dose of marijuana, short-term memory is the first to be triggered." is also blatantly false. Marijuana does not directly impact memory, but short term memory only when high off of THC or CBD is affected because the user may be 'distracted' if you will from the plant it self. Also, referring to a 'high dose' of marijuana is ridiculous. There is no such thing as a high dose of Cannabis because there is no possible way to overdose. It is strictly impossible. The most obnoxious quote that i've read from this site is, "Marijuana also impairs emotions. When smoking marijuana, the user may have uncontrollable laughter one minute and paranoia the next." I cannot believe that this would even be published. MARIJUANA DOES NOT CHANGE A USERS STATE OF MIND. PEOPLE CAN MAKE THE SAME RATIONAL DECISIONS AS THEY WOULD WHEN NOT USING THE PLANT. PERIOD. I am actually appalled by what I've read here, and I'm even more appalled by the sources you've used. Unlike true informational sites, you've only used web sources. That is completely absurd. If you look at any reasonable fact site about Cannabis you will see that the sources that are used are mainly from published books and factual citations. Please realize that much of what is on this web page is completely false and misleading. I wouldn't mind hearing a response soon to defend your case ... Spiros Thomas, 7 November 2007