Neurochemical basis of violent (impulsive) behavior

James Howard phis at
Sat Sep 28 05:47:43 EST 1996

Testosterone is the basis of violent behavior.  That is, testosterone is the
basis of impulsive behavior.  The amount of testosterone determines the ability
to control, or not, impulses.  More men are imprisoned than women.  Black men
(at the college level) produce more testosterone than white men; more black men
are imprisoned than white men.  The following is a letter describing this, which
has been sent to a number of U.S. congressmen and U.S. senators.  All, but one,
failed to even acknowledge receipt.  (It is very un-politically correct.)  You
judge for yourself.  This is from 1994.

"I am a theoretical biologist; my work contains an explanation of increased
violence in our society.  I suggest violence results directly from an increase
in numbers of individuals of higher testosterone, who arrive at puberty early.
increased testosterone and early puberty increase the probability of impulsive
actions.  The Federal Bureau of Investigation has compiled statistics which
demonstrate that I am correct.  Males kill more than females; blacks kill more
than whites.  In the remainder of this letter, I include references from hightly
reputable journals (eg. Journal of the National Cancer Institute) that
demonstrate the blacks produce significantly more testosterone than whites and
enter puberty at an earlier age.  What this boils down to is that individuals of
both races, who exhibit these qualities, are more apt to resort to violence in a
heated moment.  This is why there is so much black on black and white on white
violence; these are impulsive actions, not premeditated, thoughtful actions.
These are thoughtless actions that happen quickly, without forethought.  You, or
your aides, are aware from interviews that many of these kids, who kill other
kids, are really nice kids when they are not in a stressful, heated moment.

I am aware your background is not biological, nor are the backgrounds of those
whose advice you seek when confronting the increase in violence in our society.
You must consider, therefore, that a major explanation of human behavior is
being neglected by educators, sociologists, crimnologists, etc.  Their "model"
of human behavior suggests that almost all human behavior is determined by the
environment.  It is time a biological model is considered.  I will explain how
this produces violence in the remainder of this document; if you read this, you
should note the same mechanism also explains increased sexuality and learning
problems in our youth.  That is, all of these result from a single change in our
society, which is very easily produced and increases exponentially.

This change increases with each generation.  Not everyone is affected, but more
children are affected now than in the past.  Therefore, each past generation
contains more who notice the change.  More grandparents see it than parents.  It
occurs earlier in some places than others.  This is why some people always see
these problems in some place at some earlier time.  I think the "60s" was the
time it occurred in such magnitudes that it openly impacted our entire society.
It is a continuing process, but usually takes more time to occur in conservative

My works suggests this is a major biological change that affects both the body
and brain.  Most grandparents and some parents have noticed the change in body
size and function in children.  Children are getting bigger and reaching puberty
earlier.  "The average age of menarche [puberty] in the female has dropped from
approximately 17 years to approximately 13 years.  Thus, today maturation occurs
about 25% faster than it did 100 years ago." ("Sexual Dimorphism in Homo
sapiens," R.L. Hall, Praeger Publishers, New York, 1982, page 279).
"...children in average economic circumstances have increased in height at age
five to seven by about 1 to 2 centimeters per decade.  ...Most of the trend
toward greater size in children reflects a more rapid maturation; only a minor
part reflects a greater ultimate size."  (Encyclopaedia Britannica 1984; 5:

My work suggests a cause of this change.  The hormone, testosterone, is rising
rapidly in our society.  Increased testosterone increases body size, aggression,
and sexuality in both sexes.  (Testosterone is not "the" male hormone, men
simply produce more.)  People who produce more testosterone are more aggressive
and sexual, therefore, on average, they ultimately make more babies than those
who produce less testosterone.  (People who produce less testosterone can better
control their sexual activity; over a period of time, they will produce fewer
children.)  Ultimately, the percentage of high testosterone people, of both
sexes, increases at the expense of low testosterone people.  This changes the
averages of everything affected by testosterone.  This is why our kids are
biggfer, more sexual, and more aggressive than in the past.

The mechanism is simple: higher testosterone boys and girls reach sexual
maturity faster, increase their numbers faster, and their offspring are even
earlier and more sexual.  People seeking sexual gratification are simply more
likely to engage each other.  Sexual activity is so common today that no
"stigma" is attached; in fact, there appears to be a negative stigma attached to
those who do not indulge.  

Prior to puberty, the brain grows more rapidly than the body; it is a
competition which the brain wins in infancy and early childhood.  Because of
this brain-body competition, puberty is delayed until the brain is almost
finished in development.  Near puberty, however, testosterone increases the
body's competitive edge for growth and development which continues into
adulthood.  "The weight of the brain [in humans] reaches 90% of adult size by
age six and virtually 100% by age 12, yet body growth continues to age 18 and
beyone (note that brain growth is nearly finished before reproductive maturity
every begins)." ("Patterns of Human Growth," Cambridge University Press, 1988,
pages 60-61).

The advanced frontal lobes of the brain develop last and control formal
thinking, i.e., higher math, proper language (syntax), and the ability to form
meaningfully predictive ideas (hypotheses).  This is Piaget's final stage of
human thought development. This stage of brain development is directly dependent
on final development of the frontal lobes "from about age 11 to 14," (Science
1987; 236: 1110).  I suggest early puberty interferes with this important final
development of the frontal lobes.  For example, it was reported that
standardized test scores of 13- and 17-year-olds of 1986 are lower than those of
1970, whereas the scores of 9-year-old children have remained relatively equal
(Science 1988; 241: 1751).  I suggest this decline is the effect of puberty,
which, in this country, on average, is now occurring between age 9 and 13.  Our
children are, on average, losing the ability to handle math and English.

More importantly, our children are losing the ability to form meaningfully
predictive ideas that help control their impulses.  "What are the consequences
of my actions?"  Without the function of the frontal lobes, symbolized by this
question, kids cannot predict the consequences of, or control, their behaviors
(impulses).  Violent acts and sexual activity in children and teenagers are
actions of impulse.  These impulses are initiated by the primitive part of our
brains, which testosterone mainly affects.  Children are reaching puberty
earlier with each generation, and early puberty arrests final development of the
brain.  This means that, on average, our advanced brain is increasingly
underdeveloped with each generation.  This is why so many children cannot
control their sexual or aggressive impulses.

It is fact that, on average, the behaviors mentioned above, occur in higher
incidence in the black population.  That is, on average, black children have
more problems with math and English, score lower on standardized tests, exhibit
more aggressive and sexual impulse activity, and experience family
disintegration more than white children.  The reason, I suggest, is that, on
average, blacks, as a group, produce more testosterone than whites, as a group.
(Take note of the journal source of the following quotation.)

"This report gives the results of assays of circulating steroid hormone levels
in white and black college students in Los Angeles, CA.  Mean testosterone
levels in blacks were 19% higher than whites, and free testosterone levels were
21% higher.  Both these differences were statistically significant.  Adjustment
by analysis of covariance for time of sampling, age, weight, alcohol use,
cigarette smoking, and use of prescription drugs somewhat reduced the
differences.  After these adjustments were made, blacks had a 15% higher
testosterone level and a 13% higher free testosterone level."  (Journal of the
National Cancer Institute 1986; 76: 45).

The study, above, was of college students.  If I am correct that testosterone
adversely affects learning, then those blacks who are unable to meet
requirements for college admission, or even complete high school, may produce
more testosterone, on average.  The should exhibit even less impulse control;
this may be why there are so many black on black murders in ghettos.  This was
not a common occurrence in black communities in the depression.  Testosterone is
increasing over time.

I have suggested that increases in testosterone in our society are causing the
overall problems, i.e., increases intestosterone are causing problems for both
blacks and whites.  Therefore, the rate of teenage births should be higher in
blacks than whites but increased in both, compared to other advanced coutnries.
This is the case.

"The rate of teenage births is especially high in the black population.  An
international comparison around 1980 revealed that the black U.S. teenage
fertility rate was 2.3 times the white and 3.2 times the average of 30 advanced
countries.  The contrast is even greater among the youngest teenagers; blacks
under 18 years of age had a rate in 1980 that was more than three times that of
whites.  Nonetheless, even white teenage birthrates were 40% higher than the
average for other advanced countries."  (Science 1986; 234: 554).

Not only do blacks, as a group, produce more testosterone, which I have
suggested, increases the onset of puberty, they do, in fact, reach puberty
earlier than whites as a group.

"Black youths are known to enter into puberty at a younder chronological age
than white yourth."  (American Journal of Diseases of Children 1991; 145: 142).

Again, it is my hypothesis that the violence, sexuality, and learning problems
of our youth result from increased testosterone and early puberty in those
affected.  High testosterone and early puberty adversely affects development of
the part of the brain which controls impulsive behaviors, i.e., the advanced
forebrain.  This combination should generate these problems, and they should be
exacerbated in areas wheere high sexuality rapidly brings high testosterone
males and females together.  The result is an extremely rapid increase in high
testosterone, early puberty, and their combined effects on impulse control.  As
people of lower testosterone are literally driven away, the problem becomes more
concentrated.  Impulsive acts also become concentrated; this is why there is so
much black on black and white on white violence.

James Howard

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