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The relationship between the
brain and behavior is reciprocal. That
is, the brain controls behavior, but behavior also feeds back information that
influences the brain.
I. TOUCH
A. Sex Differences In Regards
To Being Touched And Touching Others
1. Touching others:
a. Women are more likely to touch, kiss, and embrace friends and
family.
b. Men tend to limit touch to a handshake
c. Regardless of sex, research has shown that those who are
comfortable touching others are more cheerful, less conforming, and less
suspicious of others’ motives. Whereas
those uncomfortable with touching others have lower self-esteem and are
generally more socially withdrawn.
2. Being touched:
a. One study found that women
reacted positively (i.e., lower blood pressure and reduced anxiety) when
touched by a nurse before an operation.
In contrast, the same type of touch (i.e., increase blood pressure and
anxiety) upset men.
B. Importance Of A Mother’s Or Father’s Touch (Brains need for touch
demonstrated)
1. Premature
Infants and the effect of human touch (Field, 1986). When a mother
interacts with her newborn child, much of the interaction is physical: the
mother usually caresses and strokes the baby. Several experiments have
indicated that stroking and massage promote growth.
a. 20
premature infants received massages (45 minutes per day for 10 days) and 20
premature infants received no massage.
b. Results:
Massaged infants gained 47% more weight, were more active, and more alert. At 8 months, massaged infants were still
showing a weight advantage along with more advanced cognitive and motor
development.
2. Infant
rats require a mother’s touch for normal growth and development.
a. Short-term deprivation of
mom’s touch has dramatic effects on the rat pup. These can be reversed by reinstating mom’s touch or with a touch
by an experimenter with a brush that mimics the mom’s touch.
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These
examples indicate that the need for a mother’s (or caregiver’s) touch is brain
based.
3. Psychosocial
Dwarfism: failure of the hypothalamus to produce growth hormones. This is due to psychological and social
factors and not nutritional factors (it is caused by emotional deprivation)
a. Video showed examples of
children who were brought up in orphanages and who received food, shelter, and
clothing, but who did not receive regular interaction with their “care-givers.”
b. This is a reversible
disorder: These children catch up to their peer in growth development when
placed with a normal family in which they receive the emotional interaction
that had been. For example, one study
showed an average 8-inch height increase, in one year, for children with this disorder
when the average growth for normal children, for this same time period, is 2 ½
inches.
4. Early
touching has been found to not only help rats grow and develop early in
life, but also helps them cope with stress better throughout their
lives. This in turn serves to decrease
the normal effects of aging such as learning difficulties and diseases of
senility. Why? See below.
II. STRESS
A. How Rats Are Affected By Stress.
1. Secretion
of glucocorticoids which increases heart rate, decreases digestion, and
enables the organism to better deal with the stressor.
a. Problem
with extensive exposure to glucocorticoids is that they can kill brain cells
-- especially those in the hippocampus, which is a critical area for learning
and memory.
2. Effects
of stress on aging.
a. Animals
who are handled when young are more capable of turning off the stress response
than nonhandled rats. Therefore,
nonhandled rats will be exposed to higher levels of glucocorticoids than
handled rats.
b. Nonhandled rats also show major impairments in
learning and memory in old age.
(1) Example:
Rats learning where platform is in a pool of cloudy water.
(a) Handled
rats learn this task at about the same rate as young rats.
(b) Nonhandled
rats take a significantly longer to learn this task.
B. Social Structure Of Baboon
1. For
baboons, where you are in the status hierarchy has everything to do with
your quality of life and how your body is functioning ® it influences the baboons reproductive
system, immune system, cardiovascular system, and cholesterol (correlational study
first)
a. From
research on baboons we now know that the baboon gets his/her high rank first
and then his/her body starts working better (naturalistic observation). Indicating that rank is responsible for body
functioning. Conversely, body
functioning is not responsible for rank.
2. What
is it about high rank that makes a baboon’s body work more efficiently?
a. Stress has a lot to do
with control over your life, control over situations, and predictability of
your environment. For a dominant animal he/she has a lot more control over
his/her life than does a subordinate animal.
b. Style of dominant animal also
matters. Dominant animals with lots of
cooperative partners and social affiliations have the best physiology.