Neurogenesis Paper

7/30/2019 Neurogenesis Paper

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The Effects of Neurogenesis On the Brain and the Mind

Once upon a time in the kingdom of Brainia there lived a beguiling old wizard

who concocted an evil plan. He cast ignorance over all the people, making them

depressed in the process. His reign of mass ignorance gave him power, made the people

dependent on his happiness pills, and made all but the younger generation believe they

could not learn anything new; they had reached their age limit. The people were

hopelessly distraught. However, one day a valiant young prince came running into the

village. He immediately saw through the wizards smoke and mirrors and decided he had

to help them. He started with the younger generation; he reintroduced them to physical

exercise, which reminded them of their previous culture; he taught them new lessons and

crafts, and he helped them build permanent housing for the future. He helped the older

generation by rallying them out of their hopeless dormancy, thus making them active

members of the community once more. The wizard saw what this sagacious young prince

had donehe had given the people knowledge and knocked them out from under his

spell; the people were once again happy, thriving members of the community. The wizard

denounced the prince and attacked his character, but now the people could see through

the wizards lies. The wizard was banished, never to return again. The people made the

young prince their king; he assured them that under his rule they would prosper and never

be neglected again. They all lived happily (and efficiently) ever after.

Like the good people of Brainia, our brain necessitates a myriad of activities that

we do not necessarily provide it. The wizard, like the previously held beliefs about

neurogenesis, still often holds our minds; nevertheless, the line of thought commanding

that our mind is incapable of controlling all aspects of our body is slowly diminishing.


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What we need now is global, cognitive liberation from the fetters of past beliefs. If there

was a prince who could tell every individual the news that our brains can combat

depression and other serious psychological disorders and continue to produce new

neurons throughout lifeand that physical exercise is the key to open the doorwe

might not only live longer, but also be happier, more intelligent people. The dogma of the

early 20th century dictated that our brain would stop producing neurons after early

childhood, but recent studies have proven this to be completely false. New methods are

currently being developed to map and apply the development of neurons; the 21st century

is indeed an amazing time to live. The rules are not set in stone. Who knows what other

walls we will tear down?

ABriefSummary of Neurogenesis

Scientists have always known that early in life the brain creates neurons, a process

known as neurogenesis. Neurons are created in several parts of the brainthe Olfactory

bulb in the frontal lobes, the Caudate nucleus in the center of the brain (as can be seen in

the picture below from SFN)but neurogenesis is most concentrated in the


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hippocampus, an area of the brain associated with learning and memory, more

specifically the hippocampus dentate gyrus (Begley 55; Goldman 16; Neurogenesis n.

pag.).

The life of a brain cell, however, can indeed be a short one. The Society for

Neuroscience (SFN), an organization dedicated to the study of neuroscience, identifies

that: . . . thousands of new cells are produced in the hippocampus each day, although

many die within weeks of their birth (n. pag.). SFN also remarks that this is one of the

reasons that it took scientists so long to find signs of neurogenesis in the adult brain.

You may be asking yourself: why do so many of the neurons that the brain

produces die; isnt that a little redundant? It does seem rather redundant for so many of

these brain cells to die instantly after their creation, even a week or two after creation;

fortunately, there may now be an answer of how to retain more neurons. Sharon Begley,

science columnist and a senior editor ofNewsweekmagazine, provides a possible answer

in her book Train Your Mind Change Your Brain, in an experiment conducted by Fred

Gage, a laboratory scientist at the Salk Institute in La Jolla, California. Gage

demonstrated that mice in enriched environments (cages with wheels, tunnels, toys, other

mice, and overallentertaining) vs. mice in plain cages (no interaction with other mice,

simple steel bar cages), actually had more neurons (57-58). This seems to be common

sense if you think about it: of course you are going to create more memories if you add a

dash of variety and new experience to your diet. Gage believes that the enriched

environment is what helps retain neurons: Usually, 50 percent of the new cells reaching

the dentate gyrus of the hippocampus die. But if the animal lives in an enriched

environment, many fewer of the new cells die (qtd. in Begley 66). However, this must


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be distinguished from neurogenesis itself. Gage further notes: Environmental

enrichment doesnt seem to affect cell proliferation and the generation of new neurons,

but it can affect the rate and the number of cells that survive and integrate into the

circuitry (qtd. in Begley 66).

While Gage clearly demonstrates that environmental enrichment does help retain

neurons, I believe there is more to it than that. My answer: stress. With my previous and

current research I have found that stress can cause not just mental, but actual physical

ailments. As Matt Ridley, a former science editor, Washington correspondent, and U.S.

editor forThe Economist, writes in his book Genome: It is a remarkable fact that people

who have been preparing for an important exam, and have shown the symptoms of stress,

are more likely to catch colds and other infections, because one of the effects of cortisol

is to reduce the activity, number and lifetime of lymphocyteswhite blood cells (149-

151). Ridley explains that when you have excess amount of cortisol in your system, you

are by definitionunder stress (139). Ridley also mentions: The death of a loved one,

or an impending exam do not speak directly to the genes. . . . the brain is in charge

(151). Since the brain can generate chemicals (such as cortisol) based on environmental

factors (such as stress), is it so hard to believe that a lack of stress, which is also an

environmental factor, can help our brain retain neurons? Furthermore, Marilyn Albert, a

neuroscientist at John Hopkins and co-director of the Alzheimers research center there,

mentions: In animal studies, a prolonged elevation in stress hormones damages the

hippocampus (qtd. in Larson 49). As you are well aware by this point, the hippocampus

is the main site of neurogenesis. This leads me to believe that environments that tend to


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be stress-free (or in this instance, entertaining) are conducive to a healthy mental, and

physical, state of being.

Studying neurogenesis is undeniably interesting. SFN points out that research has

already identified areas of the brain where neurogenesis is evident, discovered the

processes that may promote or inhibit neurogenesis, and offered a glimpse of how new

neurons may assimilate into the working brain (n. pag.). With all this information (and

more to come) neurogenesis will be an interesting field of study for future scholars,

potentially unlocking the brains unimagined capacity.

Tearing Down Walls

I know that most men, including those at ease with problems of the greatest

complexity, can seldom accept even the simplest and most obvious truth if it be

such as would oblige them to admit the falsity of conclusions which they have

delighted in explaining to colleagues, which they have proudly taught to others,

and which they have woven, thread by thread, into the fabric of their lives. (Leo

Tolstoy What is Art?)

Scholars of the previous century believed that after initial development the brain

would not (and could not) change. This conclusion has been proven to be false. They

were not obscurantists, but rather their inflexibility was justified by the unique

characteristic that neurons havetheir inability to reproduce. Fred Gage, in his defense

of previous scholars, explained that: it was inconceivable that one neuron could give rise

to another (qtd. in Begley 52). This parcel of knowledge damaged the credibility of

neurogenesis because scientists reasoned that if neurons could not divide, like other cells


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do, they could not be created. But as Begley reminds us: Neurons, after all, just arent

like other cells (Begley 52). Neurons do not conform to the norm of mainstream cellular

culture; they are rebels, in a manner of speaking. Scientific belief regarding neurogenesis

seemed to be set in stone, a practice that no scientist should ever adopt. Even when

empirical evidence was provided to the contrary, it was mostly disregarded. Nevertheless,

a scientist named Fernando Nottebohm conducted a series of experiments on birds, using

a radioactive tracer that bonds to thymidine (an ingredient of DNA), that demonstrated

the validity of neurogenesis (Begley 52-55). In other words, Nottebohms birds gave

evidence to support the theory of neurogenesis because he could show, via radioactive

tracers, where neurogenesis was occurring. Further research was conducted, and in the

1990s it was uncovered that, contrary to the previously held belief, the hippocampus does

not actually store memories but, rather, acquires them (Begley 55-56). In fact, the

hippocampus merely functions as a packaging plant and sends parcels of memories

throughout the rest of the brain for permanent storage (Begley 56). With this knowledge,

neurogenesis could finally be explained. Begley further remarks: brains have a reserve

of what are now called neural stem cells [NPCs], precursor cells with the ability to grow

and differentiate into neurons and other cells of the nervous system (56). Finally, the

door to neurogenesis was opened and ready for exploration.

Despite its legitimacy, however, all was not well in the world of human

neurogenesis. The tracer that was used to study human neurogenesis, called BrdU, could

not be implemented due to the Hippocratic Oath; BrdU is radioactive and has no known

medicinal value (Begley 61). This put a damper on the situation, disavowing any further


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research of human neurogenesis; but as we know, humanity always finds a way to get

around the rules. In fact, 2007 was an important year for the study of neurogenesis.

Two important discoveries have been made in the past couple years: the discovery

of double cortin, and in 2007, the discovery of a way to image neural stem cells (NPCs).

Dr. Jason Scalia of the department of psychiatry at Columbia University, explains the

origin and importance of this discovery: Several years ago, epilepsy researchers at Duke

University in Durham, N.C., discovered double cortin (DCX). . . . A new neuron excretes

DCX for the first couple of weeks of its life. . . . researchers can now distinguish newborn

neurons from old-timers, allowing them to precisely gauge neurogenesis rates in human

subjects (qtd. in Goldman 16). In short, we now have a way to investigate and document

human neurogenesis. I believe that this discovery will usher in a myriad of developments

in the category of neurogenesis, along with neuroscience in general. But it gets better:

researchers at the Stony Brook University Medical Center in Stony Brook N.Y. have

discovered a way to image a biomarker of neural stem and progenitor cells (NPCs) in the

living human brain. This discovery allows researchers to monitor neurogenesis. . .

(Stony Brook n. pag.). The importance of this discovery is monumental; it is the first

discovery of how to monitor neurogenesis in humans that does not require a slice of the

brain. With the implementation of these discoveries, the future study of neurogenesis

looks bright.

Studies of other substances, such as pharmaceuticals, also have a place in the

world of neurogenesis. I believe one of the most interesting studies is the study of

marijuanas effect on neurogenesis. As C. Brownlee puts it in his article High times for

brain growth: marijuana-like drug multiplies neurons: In the stoner stereotype, pot


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smokers and dying brain cells go hand in hand. However, new research suggests the

situation may be more uplifting than that. A drug that functions as concentrated

marijuana does [sic] may spur neurogenesis . . . (246). As funny as that is, it is important

to note that the article mentions no correlation between marijuana and intelligence, it just

leaves the door open for discussion. Who knows, maybe more people should be smoking

pot. According to Xia Zhang, researcher at the University of Saskatchewan:

Cannabinoids promote neurogenesis in embryonic and adult rats, and produce

anxiolytic- and antidepressant-like effects. This is widely different from effects seen for

other drugs of abuse, such as nicotine, heroin, and cocaine, which suppress neurogenesis

(qtd. in Flores 22). As can be heard in the stoner culture: baked not fried. In an article in

The Times (London, England), writer Anjana Ahuja humorously argues: The finding

raises speculation that weed could be the next Prozac. This would make it doubly useful

for future Troy leadersin a single inhalation they would be able to gain street cred and

shrug off the resulting furore (23). Further, the articles assert that one concentrated dose

does not elicit the response of neurogenesis, but ratherchronic use is the only effective

means by which neurogenesis can be met (Brownlee 246). Another unlikely discovery in

the area of pharmaceuticals and neurogenesis is the effect of Sildenafil (Viagra, Pfizer).

Believe it or not: Sildenafil (Viagra, Pfizer) may help patients recover from stroke by

aiding regeneration of brain cells. After successfully proving that the drug stimulates

cortical neurogenesis in experimental modes of stroke. . . (Rapposelli 46). This, Im

sure, is an especially interesting discovery for old men everywhere.

Exercise is Key


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One thing is for certain: the single most important thing that can be done for the

brain, to spur neurogenesis, is to exercise. The first study that asserted this claim, with

empirical evidence, can be found in Fred Gages mice experiments. Gage reports that one

group of mice was given a running wheel and the other was deprived of such privileges;

the mice that were given the wheel produced twice as many neurons as the mice deprived

of the wheel (qtd. in Begley 66). This exercise paradigm has been augmented throughout

the past several years. In 2007, Dutch scientists at the University of Groningen,

Netherlands, altered the experiment slightly, implementing the restriction of food, and

reported: Memory acquisition and memory retention and reversal learning in the Y-

maze task were all improved by exercise (Van der Borght et al. 325). Nonetheless, the

brain does not behave as we would expect it to; it is endless in its edifying nature. The

Dutch scientists found that: Memory retrieval itself induced a reduction in the number of

maturing neurons, irrespective of physical activity. Taken together, these results suggest


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that learning and memory and neurogenesis are related to each other . . . this interaction is

complex and highly dynamic (Van der Borght et al. 325).

As can be observed from the graphs above (published by Van der Borght et al.),

the mice that exercised produced more neurons than the sedentary mice in every instance,

thus proving that exercise is the trump card in the game of neurogenesis. The Dutch

experiments were an important find in the world of neurogenesis because they proved, for

the first time, that exercise not only elicits a higher response to learning, but also to the

retrieval of a memory (Van der Borght et al. 330).

In Gages mice experiments there is another important factor that makes these

tests important: the degeneration of neurogenesis through forced exercisestress. Gage

recalls that when forcing the mice to exercise, such as dropping mice in a tub of water,

neurogenesis did not occur. Begley humorously remarks in her book Train Your Mind

Change Your Brain: Forced exercise, it seems, does not promote neurogenesis, a fact

that human couch potatoes can probably exploit (68). While I do agree with Begley that

lethargic individuals might only skim over the top of this discovery, I believe that the real

matter-at-hand is stress. As I mentioned earlier, I have had several dealings with the topic

of stress in the past, and I do not believe that a couch potato refusing to exercise because

he/she may become exasperated constitutes the stress that Gage is referring to. The mice

in Gages experiments are thrown from their natural environments that they spend

everyday into a completely foreign environment in which they have to make the decision

to swim or drown. I believe that it is this completely disoriented struggle for existence

that justifies the stress the mice are feeling, not just swimming because they would rather

be sleeping, or in the case of humans, lying on the couch.


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Gage, however, does explore the issue deeper, explaining that there is more out

there than reaches the surface. As Gage explains, the voluntary aspect may be more

intricate than its stress-free corollary. When deep concentration is implemented, the brain

produces what are called theta waves; the brain produces these waves when an individual

is participating in voluntary exercise; conversely, theta waves are not only limited to

voluntary exercise; they are produced whenever deep concentration is induced (Begley

69). Therefore, as Gage understands it: the voluntary component could be the key to the

promotion of neurogenesis (qtd. in Begley 69). Although Gage is clearly an expert in

this subject, this assertion would suggest that playing the guitar, reading a book, or even

playing video games would produce as many neurons as voluntary exercise, providing

that the individual was paying attention; on the contrary, as the next couple of paragraphs

will demonstrate, this may not be necessarily true.

Due to all the recent discoveries in the field of neuroscience, mainstream

American is finally taking notice, and Americans are trying to figure out a way to decode

this data to benefit them; not surprisingly, there is now a growing market for any

beneficial information. An article in U.S. News & World Report entitled Keeping Your

Brain Fit, by journalist Christie Larson, focuses on the myriad of tactics being

implemented by average Americans to increase their mental life-span. The article makes

its predication by asserting: Alzheimers now afflicts 4.5 million people in the United

States . . . and is expected to reach 16 million by 2050. Statistics show that if we could

delay the onset of Alzheimers by five years, the number of people with the disease could

be cut in half (42). The article mentions that there are a number of cutting edge video-


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games aimed at keeping the brain in shape, so to speak. I can finally tell my dad that all

those years of playing video games were not in vain.

The most interesting piece of information in this article is the comparison of

physical exercise vs. cognitive training: . . . faithful aerobic exercise might boost

someones cognitive performance from averagesay, from 10 th place out of 20 people

tested . . . to No. 5. But cognitive training would boost the same person to eighth out of

20 (Larson 48). In other words, forget studying; go out and run before your next exam,

odds are youll do better. It is this reason that makes me doubt that finding; on the other

hand, the article does not mention what kind of tests were administered, and yet I cant

help from feeling that there is something amiss in this study. I also believe that this may

provide a valid contrast to Gages theta wave speculation. Nevertheless, whether a person

can perform better cognitively on a test is not the topic at hand; the issue is neurogenesis,

and physical exercise is most assuredly, at this time, the best way to boost neurogenesis.

Besides, if neurogenesis directly implied intelligence then, according to C. Brownlees

article High Times for brain growth: marijuana-like drug multiplies neurons, the

characteristic stoner would be one of the most intelligent men of all.

I would like to take the time here to answer a question that you may be asking

yourself: does increasing neurogenesis make you smarter? The answer is yes and no. If

you actively try to learn more, then yes, you will become more intelligent in the sense

that you know more; if you do nothing with your new neurons, then nothey will go to

waste like anything else that is not used. In Gages experiments with mice, the mice that

exercised learned to navigate the maze faster than the sedentary mice. The sedentary

mice, however, still completed the maze, they were just slower to finish than their


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counterparts. Since there is a lack of studies regarding neurogenesis in humans, it is

difficult to tell, at this point, to what extent neurogenesis will have in regards to

increasing our intelligence. If you exercise more, creating more neurons in the process,

do not expect to start quoting Socrates; you have to learn it first. Look at it this way:

increasing neurogenesis will not spontaneously generate a bridge; it will create more

materials to build a bridge. In other words, neurogenesis does not give you intelligence; it

gives you the ability to attain information more effectively and create stronger

connections, thus increasing your intelligence.

A recent article in National Geographic on animal intelligence has particularly

piqued my interest in regards to neurogenesis. Minds of their Own, an article by

Virginia Morell, a science writer based in Oregon and frequent contributor to National

Geographic, asserts that animal minds are not machines, as we may view them, but are

actually quite edifying. Morell remarks that Betsy, a six year old border collie (canine):

can put names to objects faster than a great ape, and her vocabulary is at 340 words and

counting (51). Juliane Kaminski, a cognitive psychologist who worked with Betsy,

suggests: Maybe these collies are especially good at it [language comprehension]

because theyre working dogs and highly motivated, and in their traditional herding jobs,

they must listen very closely to their owners (qtd. in Morell 49). I agree with Kaminskis

statement, but I would like to explain its correlation with neurogenesis. For those of you

who are not aware, border collies are known for being the most high-energy and

intelligent breed of dog. I suggest that these traits are not merely coincidental, but rather

cause and consequence; because border collies are working dogs they are bred to have the

endurance capacity rivaled only by that of the energizer bunnys. Spending much of their


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time working (in this case running and herding) they increase their ability to learn

twofold: the physical exercise that they endure spurs neurogenesis, and they have to pay

close attention to what they are doing. As you may remember, Gage remarked that theta

waves are produced whenever deep concentration is paid; thus, border collies not only

undergo tremendous neurogenesis, but they also produce theta waves due to their deep

concentration. If a border collie is still regularly exercised, their concentration could be

shifted from herding to language comprehension; this would account for their remarkable

ability to understand language.

That still leaves one question unanswered: why physical exercise? What is going

on at the cellular level to galvanize neurogenesis? Fred Gage offers: We think voluntary

exercise increases the number of neural stem cells that divide and give rise to new

neurons in the hippocampus . . . (qtd. in Begley 66). While Dr. Gage does propose a

legitimate hypothesis, it does not answer the question: why? But all hope is not lost.

Sandra Aamodt, editor in chief ofNature Neuroscience, a scientific journal on brain

research, and coauthor of the book Welcome To Your Brain suggests: It may be that a

pretty significant amount of deterioration in the brain function relates to disruptions of

the cardiovascular system by microstrokes in the tiny vessels of the brain (qtd. in

Larson 48). Translation, the heart and the mind are inextricably linked. This is a

fascinating piece of information because it would mean that heart and mind are even

more closely related than we may have thought. As is the case with all recent discoveries

in neuroscience, we will just have to be patient and wait to see.

Depressing isnt it: Depression and Other Diseases


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According to upliftprogram.com, a website dedicated to replace depression with

optimism, depression affects 18.8 million Americans each year. The sheer immensity of

that number is overwhelming. As a person who has seen and coped with depression in the

past, it is reassuring to know that neurogenesis may play an important hand in the

treatment of depression. The combination of pharmaceuticals and other measures, such as

exercise, to alter brain chemistry and induce neurogenesis may be the light at the end of

the tunnel for alleviating depression.

The study of neuroscience has led to new discoveries between mental diseases of

the mind and effects on the brain. According to recent studies, when an individual is

facing depression his/her hippocampus is actually shrunken in size, and the longer a

person has been depressed, the smaller it is (Goldberg D1). A discovery like this leads me

to the conclusion that perhaps neurogenesis, since its main site is the hippocampus, may

play a role in depression. Fred Gage goes so far to suggest that perhaps the inability to

experience the novelty of life (taking interest in everyday experiences) may be a cause,

but definitely a hallmark, of depression (Begley 70). Since neurogenesis gives life to new

memories, perhaps those who suffer from depression, and thus experience a reduced rate

of neurogenesis due to their shrunken hippocampus, have trouble escaping their well-

established, depressed thought pattern and thus have physical problems with the creation

of new, positive experiences and memories.

New research suggests that anti-depression medication and neurogenesis may

have a secret alliance. Carey Goldberg, writer for The Boston Globe, in an article entitled

New life inside the depressed brainNeuron growth may be key to mood disorder

treatments, studies find notes: Columbia University gave three other [macaque]


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monkeys the antidepressant Prozac, and they showed no signs of depression. Later

examination showed . . . a myriad of new cells had sprouted [in the hippocampus] (D1).

Moreover, the scientists then treated the monkeys with X-ray radiation to block their

hippocampus from producing new cells and the Prozac didnt help them at all (D1).

Certainly, this is an important experiment; this evidence suggests that Prozac is playing

cards, but neurogenesis is dealing the final hand. Goldberg points out: The theory could

explain . . . why drugs like Prozac often takes weeks to kick in . . . It could take that long

for the new neurons to develop (D1). In fact, Dr. Tarique Perera, the psychiatrist who

presented the study, insists: Its the one theory that can encompass the neurotransmitters,

the stress hormones, the structure problems and even certain behavioral aspects of

depression. . . . boosting neurogenesis may not only lift depression but actually prevent

it (qtd. in Goldberg D1). Naturally, as someone who is interested in both neurogenesis

and the treatment of depression, I am ardently intrigued by this report. Unfortunately, this

theory still has many gaps. Shawn Kohler, a researcher at the University of Illinois at

Urbana-Champaign, concludes: In mice, it takes three or four weeks for new neurons to

mature. . . . in monkeys, new neurons took a good 24 weeks to mature. We only expect it

to be longer in humans (qtd. in Goldberg D1). Talk about raining on my parade.

Incidentally, while there are some holes in the theory, all hope is not lost; after all,

neurogenesis itself was denied recognition for several decades despite empirical

evidence. Nevertheless, as reluctant the scientific community is to prove things that seem

to be common sense to us, it is for valid reasons.

Anti-depression medication has been widely used in the past several decades as

the solution to depression; however, while anti-depression medications do sometimes


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solve the problem of depression, they are more of a palliative measure than an actual

cure, often resulting with the patient unable to get off his/her medication. In my interview

with Dr. Jeffrey Black, Board Certified Medical Director of Laurelwood Psychiatric

Hospital, Dr. Black remarks that: What Ive noticed is that weve lost our way, in terms

of psychiatry . . . we look at medication as something that people have to take for long

periods of time . . . depression should be seen as episodic, not as a continuous thing.

Admittedly, one could not argue that there are no positive results from using medication;

regardless, a victim of depression (in Western Culture) is destined for a life of medication

dependence.

Fortunately, there is another route to follow in the treatment of depression:

cognitive-behavior therapy. Cognitive-behavior therapy works by changing the thought

process of victims, forcing them to quell their downward spiral of depressing thoughts

and establish new, positive ones. As a result, cognitive-behavior therapy elicits a cure for

depression by causing the victim to change the way he/she thinks. From a neurogenesis

standpoint, this is very intriguing because whether or not neurogenesis provides a

complete cure for depression, this proves that it plays a crucial role in alleviating

depression: forming new, positive memories requires neurons; therefore, it stands to

reason that undergoing neurogenesis gives the victim an abundant supply. Dr. Black

himself says: The research that having new cells come in to create new memories and

new thoughts, and learning how to deal with things differently; weve seen . . . with

SPEC scans and fMRIs . . . that the brain lights up in a very different way when you learn

how to handle your thoughts in a very different way. This proves my hypothesis; since

the brain lights up differently it stands to reason that the brain has created a plethora of


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neurons. Furthermore, Gage reports that there is evidence of exercise lifting depression,

and by now you know, exercise creates a lot of neurons (Begley 70). According to Dr.

Black: The research that Ive read is that 50-60% will do well with just medications. 50-

60% will do well with cognitive-behavior therapy for depression . . . but when you look

at both medication and cognitive-behavior therapy the success rate is about 80%. . . . So

what that means to me is that if you just give somebody a pill . . . youre really only

doing half of the job. I agree with Dr. Black because my experience with depression was

overcome initially using anti-depressants, and then going off them voluntarily and

changing my thought patterns.

In accordance with exercise, as a means of combating depression, there is, as

Gage puts it, evidence for it. Incidentally, experiments on the subject are scarce, as

human subjects were, until recently, impossible to measure for neurogenesis.

Nevertheless, I asked Dr. Black if he recommended exercise for his patients, and he

responded: as long as it is exercise that they are choosing to do. If you tell someone they

have to exercise and they look at it as a chore, I dont think it does much for them at all

except . . . maybe it makes them a little less stressed so there is some positive benefit with

it . . . It follows, then that physical exercise can reduce stress, which not only hinders

neurogenesis but undoubtedly adds to their depression. Of course, as Dr. Black mentions,

those that view exercise as a chore are probably not reaping all the benefits that

neurogenesis has to offer because they are not associating it with anything positive; thus,

they are not letting those brain cells reach their full potential (i.e. creating new, positive

experiences/memories). Furthermore, Dr. Black makes the distinction between exercising

as a chore and exercising for enjoyment: anything they can do socially, I think, exercise-


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wise can be really helpful. If they love to run, join a running club . . . theyve got to find

something that they really enjoy. . . . The people who exercise, and do something to quiet

their brain, be it yoga or meditation . . . do remarkably well and, I dont think, have as

high a chance of relapse. (As you may or may not know, relapse is considered the most

despicable aspect of depression, often becoming worse than the initial depression). As

Dr. Black mentions, people who exercise socially and concentrate on quieting their brain

do well in combating depression. I believe that the social aspect helps put their neurons to

work and helps them form new, more positive memories; in addition, I believe that

quieting their brain takes a deeper concentration, which would result in the production of

theta waves. Thus, actively taking any part in physical exercise benefits them.

Conclusion

Pragmatically, neurogenesis is a tremendous concern because research has already

led to important discoveries to elongate your lifespan and refrain from early retirement in

your cognitive career. The advent of neurogenesis has taught us that we must stay ever

vigilant and always question matters that science refutes when common sense demands it.

Modern depression research demonstrates many correlations with neurogenesis but

leaves troublesome holes; therefore, it is up to future generations, who now have

available methods to study neurogenesis, to bridge the gap. With this information in our

handswe have the power to change the way our mind works and our brain functions.

Furthermore, it is up to you to relay this auspicious herald; you must be princes to the rest

of the world still under the wizards spell. And, remember to exercise!


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Works Cited

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Documents

Neurogenesis Paper