NOTE: Free essay sample provided on this page should be used for references or sample purposes only. The sample essay is available to anyone, so any direct quoting without mentioning the source will be considered plagiarism by schools, colleges and universities that use plagiarism detection software. To get a completely brand-new, plagiarism-free essay, please use our essay writing service.
One click instant price quote
When we discuss our brain, we usually focus on the brains ability to think. That task alone is extremely complex and involved, but the brain also has many other tasks. Most of the time the brain is on autopilot, meaning that most of the activities preformed are just automatic. Our five senses; sight, sound, touch, taste, and smell, are automatically preformed in our brains. We don't have to think about how something sounds, we just hear it and we then interpret that sound. The largest area of our brain is the area that is set aside for vision, it is located in the occipital lobe.
Dr. Gerard Guarniero has been blind since birth, a defect in which he has never been able to fix. Recently, he has signed up for an experiment to test whether our eyes actually do the seeing, or is it the brain which puts the images in our head. He was hooked up to a machine that had a type of pad on the back of the chair in which you sit in. That pad contains tiny little bumps that move to trace the way an object would look. A type of camera is also connected to this chair, and that captures the images that are then transferred onto the bumps.
When the camera processes an item, it will then trigger the bumps, thus putting pressure on the person sitting on the chair. The whole point of the experiment was to try to find the answer if we can visualize objects though touch. The experiment was a success. Not only was Dr. Guarniero able to visualize an item, he was able to tell exactly what it was and the details of it.
The most amazing thing that he noted was a flame. He stated that he has never imagined that a flame would have a definite shape, because of the fact that he wasn't able to really touch a flame, the heat always got to him first. Dr. Gerard Guarniero is living proof that our vision and our brain is flexible and can be trained. From this experiment we are able to conclude that the brain is able to substitute different sensations for sight. So what is the real purpose of our eyes?
Eyes are simply sensors that send information to our brains. The eye itself is quiet interesting. The way that we process sight is this: first, the eyes' lens turns everything we view upside down. Then the all the impulses are cris crossed in the optic claim.
After that, the information is passed down the optic nerve where it finally reaches the primary visual cortex, or strenual cortex, where all of the transformations take place. Dr. Russell De Valois held experiments in where he took a few monkeys as his subjects, he then showed them pictures, and as he was showing the pictures to the monkeys, he tried to see what the monkeys actually saw in there visual cortex. He has pointed out that there is precision on what our eyes see and what we perceive we see. Dr. David Hubel and Dr.
Torsten Wiesel both received awards for there outstanding accomplishments in their study of the primary visual cortex. The primary visual cortex is about the size of a credit card, it lays on the posterior part of the brain. When cut out, we see that it is a layering structure that has certain loose ends and certain tight ends to it. In the late 1950 's, many experiments were tried to see what sort of pictures had an effect on the visual cortex. They were for the most part unsuccessful, until one day, accidentally, they move a glass slid over the projector, and a line appeared one the screen. That line was just what they were looking for.
So they classified the visual cortex to be associated with lines, edges, and bars. However, reducing the visual field to bars and lines isn't enough, there are many more different and more complicated tasks to be preformed and to be seen. De Valois stated that some of our visual neurons deal with light rays and the strength of the light rays; however, Hubel disagrees with De Valois on this subject. In the 19 th century we see different shades and different dots being used by impressionist artists for their paintings. They would put together a mixture of different colors in the forms of dots. When these paintings are viewed up close, they seem to be a blur, a person really isn't able to tell exactly one thing from another.
But when the person viewing the picture moves back, the whole painting fits together and we are able to see what the artist wanted us to see. As much as the visual cortex has been studied, laws for this part of the brain are extremely hard to lay down. Our eyes turn all of the images we see upside down. Now what if we were to reverse that, meaning what if we saw everything upside down. Susan was a volunteer who agreed to have a certain pair of glasses be put on her that would make her se everything as if it were upside down.
The reason of this experiment was to see if our brain truly is able to change for our surroundings. At first everything was hard for her, she had difficulty walking, sitting down, even pouring a liquid became a complicated task. After 3 days, she was able to write her name perfectly while looking. Then after several days, she could draw a picture and sign her name on the bottom right-side-up.
When the day came to take the glasses off, her brain now had to go back to normal so to say. At first everything felt weird, but the transformation process back to normal took only about an hour. From this experiment it is safe to state that our vision and even our brain is very adaptable to our surroundings. But we must keep in mind that seeing is a very small part of perception. Dr.
Mortimer Mishkin says that the visual cortex sends information through two parts of our body: one is the parietal lobe, the other is the ventricle part of the temporal lobe. The parietal lobe has the role of telling use where things are, in other words, how far away we have to move our arms to reach a glass. The temporal lobe helps use explain what objects really are. The most stimulating objects would have to be faces. One theory exists that our grandmothers light up certain neurons, which in turn are called "Grandmother cells." These grandmother cells are commutative cells, meaning that they need other cells in order to preform a task. We truly have no real explanation to how this works, but damage to this part of the brain will cause difficulty recognizing familiar objects.
Now the process of seeing something and then processing it takes about three tenths of a second. Movement of the impulse first starts at the back of the brain, then it moves its way forward to the frontal lobe, and when it gets there, that is where it is decided on what we exactly saw and how to act towards it. Now normal everyday movements occur vertically, unlike vision, which occurs horizontally. We must master both in order to survive in this world, therefore cooperation between the two senses is very necessary. Things like walking and sneezing have been discovered not to be learned, but inherited through genes. They are both reflexes, and we don't learn them, we just inherit them and execute them on almost a daily basis.
Dr. Rodolfo Links has been visiting Cape Cod for quite some time now in order to study the sea squid. The sea squid contains three neurons, but the two main neurons that we are going to be explaining are huge. They are so large in fact, that you can see the synapses between the two with your naked eye. A synapses lasts for just about one thousandth of a second. Neurons pass information through three parts of the brain: 1) primitive brain stem, 2) cerebellum (fundamental for movement) 3) visual cortex.
If a disease is acquired in the cerebellum, the person will have difficulty with the depth perception of an object for the rest of their life. The Phazel Ganglia is the unthinking and automatic response area. If this fails, a person has now gotten Parkinson's disease. The main reason for getting Parkinson's disease is that the chemical Dopemine isn't being produced anymore in the Phazel Ganglia.
Terry Thomas has received Parkinson's disease. His life has drastically changed right before his eyes. He doesn't sleep well at night, and when he does he has a yearning for chocolate. A person with Parkinson's also has difficulty crossing streets or even walking through a doorway, they have to be given small goals in order for them to do such a big task as doing through a door. In 1970, a new miracle drug come on the scene, L-Dopa.
The way that this drug works is that it produces Dopemine in excess, now allowing the brain to function somewhat normally. The drug gives a gradual relief of the difficulty, but it isn't a cure for Parkinson's. Another type of medication that has been considered is brain cell implants. The first brain cell implant was in 1982.
It was given to a patient with Parkinson's, and he survived the operation with a visible improvement. One positive idea to note about brain cell implants is that the brain doesn't reject tissue as easily as the rest of our body does. But the critics started writing that taking brain tissue from one person and inserting it into a stranger is completely unethical and immoral. So a alternative had to be found.
The alternative would come from our adrenal gland, which lies next to our kidneys. The makeup of the adrenal gland neurons is very similar to that of the original brain cell, and there weren't any rejections either when the experiment was preformed on mice. This procedure offers hope for the future. The doctors in charge of the operations have already completed two such operations, the first on in a male, didn't help much, because not to long after the operation he had gone back to the same stage of Parkinson's as he was before the operation. One thing is that he says that if he would be offered another operation, he wouldn't hesitate. The other patient was a female, and her changes stayed with her.
She has slightly improved, and now she is leading a better life because of it. What the future awaits us, no body knows, but the doctors are already planning patient number 3, 4, even 18. What does it mean to be human? The answer to this question can have many meaning. One answer might be that our whole existence as human beings is based on our animal instincts. We are of course animals, and we have evolved over the hundreds of years to be what we are today.
The foundation of our basic human life would probably have to be the cerebral cortex. It basically does everything we need done to survive on a daily basis: governs body temperature, heart beat, respiration, when we have to eat, sleep, our sexual drive, and it also triggers our aggression. If we were to remove it, or even damage the cerebral cortex, we would be in fact killing our very existence. One very interesting thing about the cerebral cortex is that it is automatic system, meaning it functions without us knowing it. There are three parts of the brain: first is the Brain Stem, then the Hypothalamus, and the Pituitary System. The brain stem is basically an extension of the spinal cord.
The hypothalamus contains both the very important Limbic System and the chemical Melatonin, which is most usually released at night. The pituitary gland releases a variety of hormones, it controls many aspects of body function. Pat Moore is a female that suffers from severe winter depression. During the winter time, she is very depressed, she is throughly disgusted of herself, she cry frequently, she tends to stay away from people, sleeps a great deal, and just basically stops all normal activity. She has difficulty starting different tasks, and if she ever does start them, she never finishes. She doesn't see a future at all for herself.
The handicap she has completely interferes with her ability to function as a normal human. She also explained that she felt like a bear, she went to sleep all winter, but then when summer hit, she was like a butterfly, she had all this energy, the will to go out and do things. So one day Pat went and participated in an experiment. The object was to try to rid the depression from her. So they set up huge flourescent lights in her living room, and for 3 hours a day she sat in front of the lights. After a short while of this, there was a drastic change.
Pat Moore almost seemed like a completely new person. She had lots of energy, she started writing, reading, painting, and lots of other things she loved to do. She is very grateful of this, and we are too. Now we understand that the lack of light will make us depressed and it will make the world seem to drag on forever.
Another way to get rid of depression would be also sleep. The less sleep you get, you usually lose your depression. One thing is though that sleep is only a temporary changer. There are some drugs that you can take to get rid of depression, but they may take as long as several weeks before the effects are seen, but when it does kick in, the change is for good. Our brains are closely linked to nature.
The beat of the earth is almost like the beat of our brain, we do everything hand in hand. One of the best times the see changes taking place in our brain would be at night time when we are sleeping. We sleep almost at ninety minute intervals. One of these intervals is realm, or the time when we dream. During this time, we can notice rapid eye movements, the brain is at its peak with activity. Most of this activity is experienced in the frontal lobe.
Then the other interval is deep sleep, or the time when we get the most rest. Michel Siffre is a French scientist who lived in a cave in Texas for several months. He took part in an experiment to see that when you change your environment in order to see the way the brain would react. His quarters were simple, but he had some of the best equipment available to him. His behavior and data was monitored; such as, blood pressure, heart rate, brain waves. The whole cave was absolutely clear of any natural light.
Which meant that he decided what time to get up, what time to sleep. He also decided when it was daytime, and when it was night time. We have an internal alarm clock so to say that decides for us when we are supposed to do all those things, including eating and many others. Michel found out that our body doesn't really live off the normal Circadian Rhythms that it's supposed to, but that we have a twenty five hour clock that we should be living by. This experiment has helped many business decide on shift work. About one forth of men and one sixth of women work shift jobs, but working a shifting job causes temporal chaos in our bodies.
If, for example, we try to sleep during the day and work doing the night, we completely rearrange our bodies and our body's internal clock. It is so bad that our body doesn't exactly know what to anticipate and when. Rotating shifts also cause a number of other problems, such as: sleep disorders and eating disorders. So Michel was called in to Utah to a processing factory to create a alternation to the normal one week shift changes.
He proposed that shifts be changed ever 3 weeks in a clockwise rotation; so that if you worked the night shift one rotation, the next you " ll work the morning, and so on. He also held classes on how to use your free time to the best way you can and he also taught the workers about their bodies. At the end of the three weeks, there was a drastic and positive improvement. The workers health got better, workers felt better about themselves in general, and also productivity rose.
So we learned that you can not ignore the part of the brain that controls when we sleep and when we wake. The Hypothalamus controls all this, and we have to keep that in mind when we are making work schedules. Another question we can ask ourselves is this: aggression and violence, where does it originate? Does it also control rage?
One experiment that has given us some answers was that preformed on a bull in the 1960 's. A typical fighting bull was taken and electrodes were placed in the frontal lobe next to the hypothalamus. It worked, the animal was completely cooled down when the electrodes were charged. Mark Larribus was a male that was convicted of hurting and almost killing his girlfriends 2 year old child. All he recollects for that day was that the child was crying, and he walked over to it and started beating it. He didn't even think about checking it, maybe wondering if it needed food, he went straight to beating.
When he was taken in, he became depressed, even suicidal at times. He had a diagnostic study taken on him to see what was wrong. It was also noted that he had been having more and more outbursts, and it was very hard to control them. When he had a CAT scan preformed on him, it was concluded that he had a tumor that was pressing on his hypothalamus.
It was a sist, it had filled with fluid and it was a very big threat on Mark. When he had it removed, the positive changes had occurred, he was much calmer, he had very few outbursts anymore, and he was basically a changed man. Before and during the urges of sex, many different things happen. First off, the hypothalamus sends a hormone to the Pituitary Gland, then that sends testosterone; and the testosterone in turn sends it back to the hypothalamus and the cycle starts over. There may be other types of the brain also working.
The hippocampus is a horn shaped part of the limbic system that is believed to be used in emotion, also the amygdala is a part of the brain that is found in the temporal lobe that also is believe to be involved in emotion. In the year 1978, Mitch Heller was involved in an automobile accident that has changed his life completely. Mitch was a typical red blooded man, he loved to play various sports, and he led a healthy life. But he realized that about a month after his accident he didn't have the urge to have sexual intercourse, he couldn't preform as well in bed, his voice was getting noticeably higher, and he loss facial hair. He became horrified with all this as well as confused.
One funny thing was that a month before the accident he and his wife had planned to have a baby, but now there was this set back. He only suffered a bump to the head, but he had damaged his hypothalamus. With that damage done, his brain couldn't preform the necessary steps in order to secret the hormone to the pituitary gland to have the urges for sex. So they tried to fix it. Dr. Crowley was called in, he had preformed magnificent work on the 3 way system involving the hypothalamus.
The doctor designed for Mitch a sort of portable hypothalamus. It was a small box that can be carried around your waste that contained a syringe with the hormone that is normally secreted by the hypothalamus. Then an injection is made into the abdomen, and at regular two hour intervals the hormone is injected. At first, Mitch couldn't stand the thing. He felt each injection as it went in and it was uncomfortable to carry around. But it did help.
Almost right after the first injection, he had a change in his libido, and after about 5 days, he was completely used to the device. When he got home, he had the sudden urge to go and have sexual intercourse with his wife and he felt great altogether. The two main reasons for him having this done to him were these: one, he wanted to have children; and second he wanted to live like a normal male. He was happy to note that after having this happen to him, he and his wife have had a healthy baby girl, and it was all thanks to modern science. So what have we learned, well, the human brain has changed and has been enriched throughout the years of our existence. We also have learned that we carry the baggage of animal behavior, and it affects the way we think, feel, act, and love.
Everything that we feel in our bodies is produced by the brain. Our emotions, personality, love, and hate, they are all mediated by the brain. Since emotions do not have there own separate parts in our brain, it has been very difficult to pinpoint where emotions come from. There is only one emotion so far that we know of that we can locate where it originates from, and that's anxiety. One of anxieties chief byproduct is nervousness.
Nervousness is the imbalance between the frontal cortex and the limbic system. The way that we found this emotion in our brain was completely accidental. Phineas Gage was an intelligent, well balanced man. He was a modest and good, hard worker. He was part of a team that laid out tracks for railroad cars. One day, as he had a fight with another worker over his girlfriend, he got into a terrible accident.
A steel rod had been driven through his cheek and up his skull. He suffered damage to the part of the brain that is between the limbic system and the frontal cortex. So now, he is unable to have controlled emotions. You see, the brain is like a group of good railroad layers, everyone works together to get one thing accomplished.
The limbic system passes information to the frontal cortex, and normally the two systems keep thought and emotions on an equilibrium. But after his accident, Phineas was unable to control any of his thoughts or emotions. His limbic system was free without any restrictions that the frontal cortex might have given. The reason why he might have felt very little pain during his accident was because normally, pain is sent up the central nervous system to the brain, and Substance P is then passed through the synapses of neurons if enough pain has passed through the brain. There are endorphins that lessen pain in our bodies, they are released as soon as our brain senses any sort of pain. We can also sort of "block out" pain by thinking that something makes it better.
For instance, we may think that drinking water eases pain, when in actuality it has no medical purposes what so ever. There is also a drug called morphine that blocks out the Substance P from ever reacting in our brains. Edward Williams was Phineas' doctor when he came to town that day. After examination, Dr. Williams had stated that he had severely severed the frontal cortex from the limbic system. The wound was so bad that the doctor was able to touch his two hands while they were inside of Phineas's kull.
This completely changed his life. After recovering, he faced many new changes altogether. His words were pathetic, he slurred when he spoke, he was wild and uncontrollable, he cried often and he also screamed intensely. Basically, he let all his feeling out at any given moment. What happened to him? Well, once the connection between the limbic system and the frontal cortex is gone, the limbic system then allows information and emotions to pass through the brain freely, and everything is basically uncensored by the frontal cortex.
Beating all the odds he survived, but only physically. He never recovered intellectually or emotionally. He lost almost all human contacts, but he had developed a certain bond with animals. It was said by his close friends that he was like "an animals emotions in a mans body." He died 12 years later, never fully recovering.
Chemical changes in our brain also change our behavior. Different reactions in our brain can be changed by our environment or by emotions, but most of the changes are unknown. Stressful stimuli and anxiety change the balance of chemicals in our bodies. Stress is quite noticeable in our bodies.
Under stress, our central nervous system speeds up, we have a higher heart beat, and our blood pressure rises. Stress isn't a physical event it is critically determined by the environment and by what an organism can or cannot do. We are triggered by the "fight of flight" system. It is decided wether we will stay and take in the challenge, or if we will leave the situation.
Air traffic controllers live very high stressful lives and have high stressful jobs in general. Bizzoro, a French air traffic controller working in Quebec. Not only does he have to have the all normal jobs that air traffic controller do, he also has to preform in two languages, both English and French, and that only adds to the stress. It was said that the early cave man didn't produce as much as we produce now, so therefor they had less to worry about.
We also drive ourselves too hard at work, we try to overcome the competition but in the process we are hurting ourselves. In the wild, basically all we had to worry about was what to eat and to watch out not to be eaten, all the energy came from our flight of fight system. But no during this day and age, our limbic system messages are overruled by our frontal cortex. One experiment that was performed involved rats. There were two rats, and their tails were charged with an electrical impulse, and if the rat spun a wheel, the impulse would be sent at intervals every 60 seconds. But if the rat failed to spin the wheel, it would receive the impulse at associated time periods.
The rat that did spin the wheel showed that he had control, but the rat that didn't spin the wheel showed that he had no control. Also, the rat that did spin the wheel showed that he had predictability. So in order to survive in this world, we not only need good control, but also good predictability. The more we prolong the stress on our brains, the quicker the terminal ends basically die off.
The locus coeruleus, when active, releases a neurotransmitter called norepinephrine, and that in turn activates our brain and we start to think. Another experiment was given to the rats, this time they were put into a cup filled with water and they had water wings put on them. This time the object was to see how much activity will be produced in a stressful activity. Bad reactions would be to constantly be trying to swim, trying to stay afloat, constantly moving. But the good reaction that can be produced was that the rat was trying to move as little as possible, spent most of its time just floating. The rat that was had the bad reactions showed sleep changes, feeding changes, and a lack of grooming.
So the same side effects were noted as in a clinically depressed person. When the limbic system overwhelms the frontal cortex, the link between the two is lost, and we almost in a way fry everything in between. Gaba is a chemical that inhibits cells from firing impulses. When the radar went out in the flight operators screen, he became nervous and stressed out. But gaba lowered the firing of impulses, and his nervousness was kept to a minimum.
Valium is a drug that helps many stress patients recover. It is a member of the class of drugs that improves gaba production. It also controls emotions from being expressed. Panic attacks are experienced when all the emotions in our brains are suddenly turned on and go out of control.
An injection was given to a patient that has had panic attacks in the past. This injection forces a stimulated attack on the person, and the physical as well as mental changes are recorded. First off, the patient feels light headed, then you feel weak, and the other symptoms follow. When a person has a full blown panic attack, the limbic system fires a overload of stimuli on the frontal cortex, causing everything to go hay wire. Anna Renaud is a panic attack victim.
Her attacks were getting so bad that she was forced to get medical attention at a local hospital. The first attack that she ever remembers having was about three to four years ago during an Easter dinner. She recalls she felt weak, her heart started pounding, she had a tension of muscles, and also she felt as though she had a type of lump in her esophagus that felt like she couldn't swallow. She received drug therapy, and as much as it helped, she still suffered from minor panic attacks. Soon after she was off the drug therapy, she went into rehabilitation that taught her brain how to resist the attacks. This helped her greatly, but she still had the same stressful job and she was still surrounded by stressful situations.
She was also suffering from exacerbated anxiety. This type of anxiety is felt by everyone at all the time, just some of us have it in a more profound level. People that suffer from this consider everything they do in life to be extremely stressful, they try to avoid most things in life. Valium is most often prescribed for this anxiety, and it does a great job in curing it. Anna also developed a few phobia's, or fears of things.
She was afraid to ride the metro or afraid to be in a large crowd. Her panic attacks have greatly shortened, now they last a minuscule one to two minutes. Her first day off of any medications was a bit shaky. She has just learned new techniques to try to conquer the attacks, and she has also returned to work. She now has stayed drug free, and her chances are constantly improving because of the fact that she does vigorous exercises in order to get rid of unnecessary stress. Different types of things you may also do to get rid of stress are yoga, faith, and even prayer.
Our understanding of the changes that occur in our brain has improved immensely. All advances do have the possibility to be misused in a controlled way, but the positive outcomes out weight the negative ones. As for the air traffic controller, his wife had another child. This is another stressful situation that must be dealt with care. During labor, she was given a spinal tap so that she wouldn't feel any pain what so ever, but there was a problem. She had too much stress, her blood pressure rose, she felt bad altogether, too many messages were getting sent from the limbic system to the frontal cortex.
After a few minutes of this, equilibrium was restored, and her vital signs returned to normal. There was a minor problem with the delivery, and the child had to be surgically removed, but it came out in perfect health. So the question remains "Do we have the knowledge to control all parts of life?" All we really have to remember is that behavior is a simple part of our brains' function, and we will have to find the rest out later. We are just now beginning to understand exactly how the brain works in respect to the way we memorize things.
There are two basic approaches that we have developed to learn about the way memory works: 1) we view neurons through microscopes and then try to determine the way they function; 2) we look at other human beings, the way they act, especially amnesiacs. We are faced with one of the many questions about memory, and that is "Where are our memories started?" Karl Lashley is a scientist that in the 1920 's preformed experiments to decided where the memories we remember are stored in our brain. He removed different parts of the brain from different lab rats and then studied the rats to decide if the part he took out had any affect on there past memories. He trained the rats to remember a certain type of maze, and after the rat could walk through the maze without any difficulty, he surgically removed part of that rats brain.
After the rat had time to recover from the operation, he put that rat inside of the same maze and tried to see if the rat's memory was at all altered by the operation. Through his many experiments, he concluded that our memories were stored in the temporal lobe of the brain. Dr. Donald Hebb helped and also studied with Mr.
Lashley. He stated that if more then one fifth of the frontal cortex is removed, that it then starts to have a negative effect on memory; but if less then one fifth of the cortex is removed, the no real loss of memory is experienced. He disagreed with Mr. Lashley, however, because Lashley stated that memory can be localized into a certain part of the brain. Dr. Hebb stated the complete opposite, that memory cannot be localized in any real part of the brain.
Dr. Hebb also proposed the idea of cell organization. Wilder Pea field, who was also accompanied by Dr. Hebb, was fascinated on how the brain actually remembered what we do.
He stated that memories were stored in the temporal lobe, and he concluded experiments to support this. He had a female patient in which he operated on her temporal lobe. Before any operation, he always did stimulating exercises on the part of the brain he was going to work on so that he could exactly know what he was going to work with. Our memories are stored biologically in our brain, not physically. In just about every action we ever do, there are chemicals involved that either excite or inhibit our neurons to act or not to act accordingly to the stimuli. When we remember thing...
Free research essays on topics related to: temporal lobe, central nervous system, order to survive, frontal lobe, part of the brain
Research essay sample on Central Nervous System Part Of The Brain