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Biology 202
2004 First Web Paper
On Serendip



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


kaitlyn a's picture



Anonymous's picture

I know man i smoke weed when

I know man i smoke weed when somebody then piss me off,....that calms my nerves i be having my room lit like i was in Jamaica......Weed is good for u...."I bet u won't try just one"..Pringle man quote!!!

Anonymous's picture

...See its people like you

...See its people like you that i cant stand im a smoker and i get up go to school everyday pass with a 3.9 gpa im one of the most athletic people at my school and i smoke every day (the guy who wrote this blog has no grammar or spelling skills)

Anonymous's picture

SIMPLY AMAZING!!!!!!!!!!!!!!!

I'm so sick of people judging potheads like were freaks. I got 3.7 gpa and i'm smokin weed everyday

TOKEZ's picture

Marijuana Crazy

Marijuana is an addiction of mine it is bitter sweet i should say. I have done marijuana more times than i can remember but i'm going through life as best as I can. My life is sometimes complicated but who's life isn't?. My familia doesn't like me using marijuana but i'm in love with Mary Jane. Marijuana has got me in trouble but I think I just have to remember the #1 rule NEVER GET CAUGHT. I'm doing fine in school I used to have 3 F's now I only have 1 F. And remember there are alot of haters out there so just live your life the way you want to and remember everything you do has a conciquence.

Dude's picture

i aggre with u dude

Yeh man,there is completely nothing wrong with our goods**t,i have been smoking science iwas 17yrs, now i'm 25,and i'm still strong,they should put billboards on our national roads that says: "dont drink and drive,smoke and fly"....

Anonymous's picture

Helllz ya

I got only one freaking F on my report card and i can still sit here and smoke blunts till i past out wake up and do it before school and still get good grades for the people that judge just fuck off man it realize people it anit hurten anyone but us its our chose and if you dont like it then leave the fucking room. you dont have to stay by us...!!!!!!!!!!! THANKS

Anonymous's picture

heh heh

So in general judging by your writing, grammar and spelling you got all D's and one F, am I right? And for all of you people that "Choose" to break the law and teach your children to as well need to grow up, that's what this drug is doing to your minds. You might as well roll "Blunts" for your kids while they're in the crib, get them hooked while they're really young. So insane, Weed is a "Kids" drug and that's why most that smoke it as a recreation are immature and have nothing to add except immature and poorly written comments, save for a few.

Anonymous's picture

When you get married and

When you get married and have kids are you gonna let them smoke with you everyday?

ankou's picture

that is an understatement

that is an understatement because society makes weed out to be this terrible drug that will kill you. the benefits though are actually good so if you are not ignorant then yes it shouldn't really matter and you really shouldn't be judging people that do.

tee's picture

Why Not

I would always let my kids smoke with me if thats what they want to do. I honestly see no problem with it why have your kids sneeking around doing it when you guys can openly smoke it, it wouldnt be fair to me if i didnt let them cause i smoke that stuff everday....smoking with your kids can also help you build a better relationship we all know that all kids have a hard time talking to their parents if you sit down and smoke with them and show that there is nothing that they have to worry about they will be more open to telling you what is going on with their life....i always wished i had the chance to sit down with my parents and smoke with them

Poopie's picture

no way >;P

u shudnt let ur kids do that......
parents shud b a gud exmple 4 their kids..

pot smoker!!!'s picture

thats a load of crap

thats a load of crap

Anonymous's picture

why isn't this being a good example

How are you not being a good example 2 ur kid's if you smoke wed with them

wouldn't u tell ur kids not to lie to you

well if they are smoking behind ur back then they would be breaking the rules

so if u smoke weed with them then they wouldn't be breaking the rules

So over all u would be setting a good example to your kids

Fully functioning smoker's picture

I am married with kids, and

I am married with kids, and although mine are too young to be doing anything mind-altering, I can honestly say I'd rather them do nothing of course, but if I had to choose between marijuana and alcohol, I would choose marijuana. Hands down.

Anonymous's picture

Reply to when you get married and have kids

Yes I would let my kids smoke with me everyday.Cause I would then know that they were safe from the law.If they wanted to smoke it then hell yea why not.People let ther kids&other peoples kids drink at parties then turn them out to drive home.So I think it would be safer if we let our kids smoke POT than drink.Drinking kills more people than someone smoking pot. My dad has drinked all my life and do you know he has had more accidents than my husbad who smokes pot every day of his life.I mean he smokes from the time he wakes up tell the time he falls a sleep.But my dad drinks the same way.So I think that you are safer with pot than alcohol.And no I do not smoke pot!!But I do not see why people think it is such a bad thing!!!

Anonymous's picture

And they'll grow up with a non-realistic veiw on life

I you're going to sit there and let your kids smoke weed with you, they'll grow up thinking its okay to be a pot head, and so will their children, and we'll have a world of idiots that can't handle reality so thay take drugs, and that is totally pathetic, I grew up without my mother because she's a messed up person that is unfit to be a parent because she smokes to much weed ... what the hell is the purpose to it anyway, get some friends to go out with and have some fun instead of spending your life getting stoned

Anonymous's picture

Weed is designed for medicinal purposes

true that, they need to get a life and have self control not by taking something to perform good or bad at school.if they said there's no more weed would they still take control of their lives just like before? Don't think so cause it has become a need, a habit. Fix ur problems, get a life and take control of it not through Weed!

Anonymous's picture


people dont do pot because life is too hard, they do it cuz its fun. i grew up without my father cuz he was a crackhead, but at least i dont base my decisions on things that are wrong with my life. wats wrong with being a pothead? nothing, u just think there is because the structural foundation that your parents inadvertently set up tells you its a bad thing and you just dont question it because you couldn't being wrong. and i think your mom ruined her own life, it it wasnt weed it would be something dangerous like crack or herion.

Anonymous's picture

How do you know she wouldn't

How do you know she wouldn't have been an unfit parent without the mj? I know many many people who smoke daily, who are successful business men/women, who work their 40 hours a week, support a family. The mj doesn't make you lazy (yes it can make you tired) it just happens to be that 99% of the population are extremely lazy in the first place!
Your just like every NON smoker in the world who has had the "WEED IS BAD" thought crammed into your brain from the day you were born. I could sit here and argue with everyone naysayer on this page. But you Truly will not understand until you have tried it for yourself. and if you have tried it, and it made you lazy, than you are just a lazy person to begin with.

Kendra M's picture


Wow, your post blew me away. I just wanted to say thankyou for being a kindof spokesperson for a smoker like me. My parents believe it's wrong my cousin believes it's wrong and most of society believes it's wrong or dangerous. I have had no permanant side affects and in my own experience it has not been a gateway drug. If anything pot stopped me from trying harder drugs. I found something I could do with my friends that didn't risk my life or have me driving drunk. Anyway I guess that's all. Thanks again
age 20

Anonymous's picture

Ther world is not all lovey dovey

Because of weed I have done harder people who say its not a gate way drug....IT IS!!! smoking Ganja opens up your mind to do things you have never done before...

please dont be ignorant...

I am a pot smoker...20 years now

Anonymous's picture

You have no self control,

You have no self control, that's your fault, not the plant's.


Pure ignorance!

You're an idiot. I know a ton of people who have only ever smoked weed. Take me for instance... I don't drink, do drugs or even smoke cigarettes. In fact I have never even tried a cigarette, but I smoke weed everyday. Also the Dutch did a study in which they legalized marijuana and when they did they saw that the use of hard drugs had dropped tremendously. How in the hell do you explain that with your ignorant statement that, "weed is a gateway drug." You just did not have the self-control or will power to say "NO!" That is not the weeds fault. Anyone who starts doing other drugs, is lazy, or stupid after smoking weed was already like that before they even lit up. DON'T BLAME WEED FOR YOUR STUPIDITY, IT IS NOT YOUR ESCAPE GOAT!!!

Brandon Smith's picture


its called scape goat lol but ima go light up and leave ur nerdy ass to it :P

Anonymous's picture

smoking weed can affect your lungs too

I think u shld go get a medical check up for your lungs...cause SMOKING effects the lungs, its just a matter of time thats all. who knows maybe ten years time you'll agree to them that "smoking is wrong".

Anonymous's picture

thats what vaporizers are for

thats what vaporizers are for fuck nut.
read up people, read up before you make a dick out of yourself

Mansi's picture

Amen! well said well

Amen! well said well said!!!!!!!

Anonymous767's picture

I agree, very well said.

I agree, very well said.

Anonymous's picture


as do I! we r all so incredible!!!!!!!!!

Anonymous's picture


what do you say about te smoke inhaled into te lungs?

Anonymous's picture


you have to inhale it or you wont get high chiefin is great when you have a lot of weed

Anonymous's picture

Prohibition does not work

Prohibition does not work and everyone knows this proof is in the pudding.Corrupt companies dont want the people to see the benefit MARIJUANA and HEMP have to offer,PAPER,FABRIC,FOOD,BIO-DIESEL FOR AUTOS,MEDICINE,BUILDING PRODUCTS for houses,are just a few things this plant can offer and at a cheaper production cost.This plant can bring down the whole system and when the general public wakes up to these facts then the fear of Marijuana will go away.Do your own research on the benefits of Marijuana and Hemp and learn for yourself why the government tries to hide the truth,IT CAN DO MORE THAN GET YOU HIGH.

Serendip Visitor's picture

frustration towards all people "addicted to weed". hah

i know im replying to someone but its to everyone.
there isnt a reason for a person to smoke marijuana.
then again there isnt a reason for someone to refrain from it.
But in the end the only reason people will smoke on and on continuously, is just for an identity. They want to be known as the smoker.
And alot of people that are sober and clean of drugs LET IT BE KNOWN that they are clean of drugs and would never think of trying it. so they want to be known as the clean intelligent type or whatever.
If someone is interested in trying it out, it obviously doesnt kill you and its effects arent to drastic, so try it.
Just remember you were born sober, and your body will return to soberness.
Im just saying, needing to smoke all of the time is just idiotic and childish, people need to grow up.
Its natural to be curious but dont start smoking thinking its going to bump your status.
Status is out of the window once your in the adult world.

Anonymous's picture


No one smokes pot for the "status boost". Thats ridiculous,you smoke to chill and relax when you have down time to think about things... and marijuana only inebriates beginner smokers severely, daily tokers are under more control of themselves due to their tolerance.

Anonymous's picture

He was probably one of the

He was probably one of the lonely kids in school and extremely un-educated at that...I'm surprised you managed to event comment without engaging with anything useful or important on the debating topics of Marijuana.

Cora 's picture


And truth be told.