Transcript
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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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