Human Intellect Backsliding From Lack of Evolutionary Pressure:
Study
Story at-a-glance
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The optimization of a vast arrav of genes related to
intelligence may have peaked in the early stages of human
evolution, when your ability to survive depended much more than
now on your higher cognitive faculties
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Now that this evolutionary pressure is gone, genetic mutations
that interfere with optimal intellectual function, or even
contribute to disabilities, are becoming more common; it’s
estimated that while there are anywhere form 2,000 to 5,000
genes that play a role in intellectual ability, all humans now
have two or more mutations that may disrupt their intellectual
or emotional stability
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On a personal level, you can impact your brain function and
cognitive abilities by making simple tweaks to your lifestyle
and daily routine
By Dr. Mercola
You might think that human intellect is like riding a bike...
once you've got it, it's there for good.
But new research from Stanford University suggests that not
only is human intellect not a "given"... it may
actually be regressing.
Are Humans Losing Their Intelligence?
In the analysis, written by Gerald Crabtree, a genetics
professor at Stanford University, it's explained that the
optimization of a large number of genes related to intelligence
may have peaked in the early stages of human evolution, when
your ability to survive depended much more than now on your
level of intellect.1
But nowadays, that evolutionary pressure is gone, and you can
survive with even minimal levels of intelligence. So the genetic
mutations that cause intellectual disabilities have no reason to
be removed through selective pressures, from a survival
standpoint. It was estimated that while there are anywhere form
2,000 to 5,000 genes that play a role in higher cognitive
faculties, all humans now have two or more mutations or
deletions that may harm their intellectual or emotional
stability.2
"New developments in genetics, anthropology, and
neurobiology predict that a very large number of genes
underlie our intellectual and emotional abilities, making
these abilities genetically surprisingly fragile," the
analysis explains.
Analysis of human mutation rates and the number of
genes required for human intellectual and emotional fitness
indicates that we are almost certainly losing these
abilities."
It's likely that such genetic changes will only continue to
accumulate, albeit so slowly that, according to Dr. Crabtree,
we'll have solutions available in the future to "correct" them.
Are You Being Deceived About Your Own Intelligence?
Do you find it hard to believe that your intelligence may be
slipping? Or that you may have adverse genetic changes tied to
your intellect or emotional health that didn't exist many
generations ago?
This is actually quite common, as "people tend to hold overly
favorable views of their abilities in many social and
intellectual domains," according to David Dunning, a Cornell
professor of social psychology. After conducting four studies,
Dunning and a colleague determined that some people overestimate
just how smart they are, and the less skilled a person actually
is, the less able they are to realize it.
" ... this overestimation occurs, in part, because
people who are unskilled in these domains suffer a dual
burden: Not only do these people reach erroneous conclusions
and make unfortunate choices, but their incompetence robs
them of the metacognitive ability to realize it," they
wrote.3
To put it simply, you have within your realm of experience
"known unknowns" and the far more daunting "unknown unknowns.
"The latter are those circumstances that are so far removed from
our ordinary experience that we cannot even fathom them. A sign
of an intelligent person is knowing there are things you don't
know, but a sign of an even more intelligent person may be
knowing there are things that you don't know you don't know.
When you may run into trouble, on the other hand, is when you
believe you know everything and close your mind to learning any
new ideas. Unfortunately, a great deal of the underlying
premises upon which our society was built fall into this realm.
For instance, many "conventional" experts in the field of
medicine refuse to believe in these "unknown unknowns" -- a
definite sign of ignorance if there ever was one. As Voltaire
said, "A state of doubt is unpleasant, but a state of certainty
is ridiculous."
Other Evidence of a "Dumbing Down" Effect?
Education is the one social factor that has been consistently
linked to longer life, regardless of what country you live in.
But the idea that the only way to get properly educated is to go
through a formal school system may be a misnomer.
According to Charlotte Iserbyt, who served as Senior Policy
Advisor in the Office of Educational Research and Improvement
(OERI), U.S. Department of Education, during the first Reagan
Administration, the Department of Education's goal is
manipulation of public school curriculum to
promote a political agenda.
During her tenure as Senior Policy Advisor, Iserbyt was
shocked to learn that her employer promoted the purpose of
education as a vehicle to change the thoughts, actions and
feelings of students. Good teaching is defined as "successfully
challenging students' fixed beliefs." In this way, children may
come out of the school system as though they are molded cogs in
a machine, rather than the independent thinkers they entered in
as.
This is in no way a reflection on the many dedicated and
talented teachers we have here in the United States. Rather,
it's a perspective of some of the issues that are present at
higher levels that may make it nearly impossible to provide a
solid education no matter how skilled or excellent the teacher
is. In a culture where intelligence and education are highly
valued, it is, at the very least, interesting to speculate that
perhaps the education system itself could be contributing to,
rather than combatting, the dumbing down effect that may already
be occurring in evolutionary terms.
7 Tricks to Give Your Brainpower a Boost
There's no need to simply sit idly by while your intellect
fades away. There is quite a bit you can do to not only protect
what brainpower you do have but also to significantly enhance
it. Even Dunning found in his study that the participants were
able to improve upon their skills, and therefore also their
metacognitive competence (which, ironically, helped them realize
the limitations of their abilities).
If you want to boost your intellect, stave off mental aging,
and maybe even pass these intellectual gains on to your
children, try:
1. Exercise
Exercise encourages your brain to work at optimum
capacity by causing nerve cells to multiply, strengthening
their interconnections and protecting them from damage.
During exercise nerve cells release proteins known as
neurotrophic factors. One in particular, called
brain-derived neurotrophic factor (BDNF), triggers numerous
other chemicals that promote neural health, and directly
benefits cognitive functions, including learning. Exercise
has even been shown to boost mitochondrial genesis in nerve
cells, optimizing their ability to produce energy and
function at peak levels.
To get the most out of your workouts, I recommend a
comprehensive program that includes
Peak Fitness high-intensity exercise, strength training,
stretching, and core work.
2. Animal-Based Omega-3 Fats
Docosahexaenoic acid, or DHA, an omega-3 fat, is an
essential structural component of both your brain and
retina. Approximately 60 percent of your brain is composed
of fats—25 percent of which is DHA. DHA is also an essential
structural ingredient of breast milk, which is believed to
be a major reason why breastfed babies consistently score
higher on IQ tests than formula-fed babies.
The influence of omega-3 fat on physical and mental
health has been the subject of intense research over the
last four decades, and there's compelling evidence that
animal-based omega-3 fats can help not only to reduce the
symptoms of a variety of psychiatric illnesses and
degenerative brain disorders, but also slow, halt and
sometimes even reverse the underlying disease process.
3. Sleep
Sleep is not only essential for regenerating your
physical body, but it is imperative for reaching new mental
insights and being able to see new creative solutions to old
problems. Sleep removes the blinders and helps "reset" your
brain to look at problems from a different perspective,
which is crucial to creativity.
Research from Harvard indicates that people are
33 percent more likely to infer connections among
distantly related ideas after sleeping, but few realize that
their performance has actually improved. Sleep is also known
to enhance your memories and help you "practice" and improve
your performance of challenging skills. In fact, a single
night of sleeping only four to six hours can improve your
ability to think clearly the next day.
4. Vitamin D
Activated
vitamin D receptors increase nerve growth in your brain,
and researchers have also located metabolic pathways for
vitamin D in the hippocampus and cerebellum of the brain,
areas that are involved in planning, processing of
information, and the formation of new memories.
Appropriate sun exposure is all it takes to
keep your levels where they need to be for healthy brain
function. If this is not an option, a safe tanning bed is
the next best alternative, followed by a vitamin D3
supplement.
5. Optimize Your Gut Flora
Your gut is your "second brain," and your gut bacteria
transmits information to your brain via the vagus nerve, the
tenth cranial nerve that runs from your brain stem into your
enteric nervous system (the nervous system of your
gastrointestinal tract). There is a close connection between
abnormal gut flora and abnormal brain development, and just
as you have neurons in your brain, you also have neurons in
your gut -- including neurons that produce neurotransmitters
like serotonin, which is also found in your brain and is
linked to mood.
Limiting sugar and processed foods, while eating
traditionally fermented foods (rich in naturally
occurring good bacteria), taking a probiotic supplement and
breastfeeding your baby are among the best ways to optimize
gut flora and subsequently support brain health.
6. Vitamin B12
Vitamin B12, or rather a lack thereof, has been called
the "canary in the cobala-mine" for your future brain
health, and recent research has bolstered the importance of
this vitamin in keeping your mind sharp as you age.
According to the latest research, people with high levels of
markers for vitamin B12 deficiency were more likely to score
lower on cognitive tests, as well as have a smaller total
brain volume,4
which suggests a lack of the vitamin may contribute to brain
shrinkage.
7. Challenge Your Mind
One of the simplest methods to boost your brain function
is to keep on learning. The size and structure of neurons
and the connections between them actually change as you
learn. This can take on many forms above and beyond book
learning to include activities like traveling, learning to
play a musical instrument or speak a foreign language, or
participating in social and community activities.
Another important method? Brain aerobics. As with
learning, challenging your brain with mind-training
exercises can keep your brain fit as you age. This can be
something as simple as thinking of famous people whose first
names begin with the letter A, doing crossword puzzles or
playing board games that get you thinking.
Research has even shown that surfing the Web activates
regions in your brain related to decision-making and complex
reasoning.5
So unlike passively watching TV, using the Internet is an
engaging task that may actually help to improve your
brainpower.
© Copyright 1997-2012 Dr. Joseph Mercola. All Rights Reserved.
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