Developmental psychology.pdf

Principles of Motivation 293
Figure 11.6
Chimpanzee Mating. Certain mating
patterns are preferred but there is
also variety Here the male adult
combines mating with feeding, while
a young chimp observes with
interest.
Parental Motivation The survival of the species also depends upon parental care,
and here again we see the various influences of hormones, the environment, and prior
learning. In lower animals hormone secretion is the basic condition for maternal behavior,
meaning care of the young by the mother. The maternal hormone is prolactin, secreted
by the pituitary gland, and it is influential in sexual development as well. It is of marked
significance in lower animals, which show highly stereotyped maternal behavior.
Investigations with the rat indicate that prolactin, estrogen, and perhaps two other
hormones play a combined role in initiating maternal behavior (Lamb, 1975).
Maternal behavior in monkeys is more variable, but three general stages have
been identified. First, there is attachment and protection, in which the newborn receives
unconditional love and care. The mother constantly satisfies the infant's nutritional
and temperature needs, provides it with security through physical contact, and
protects it from dangers. After three months, during the stage of transition, the mother
occasionally dissociates herself from the infant, disciplines it with increasing frequency,
and relaxes her restraints on its exploratory behavior. The infant is prompted
to venture into a wider world partly to escape punishment. The third stage, separation
or rejection, may appear suddenly, often precipitated by the arrival of another baby.
The newborn becomes a love object in the first stage of maternal care, and the care of
the older baby is commonly taken over by an adult male, usually the father (Harlow
& Harlow, 1966).
At the human level, despite the presence of prolactin, there is no worldwide
pattern of mothering, unless it is feeding the child at the breast. But even breastfeeding
is not universal, and in different cultures there are marked differences in weaning,
both of which indicate the role of learning. North American mothers usually wean
their children gradually; some mothers in the South Pacific do so abruptly, putting a
red pepper on their nipples. In areas of Poland it has been the custom to wean suddenly,
on a day selected in advance, when the child becomes approximately 18 months old
(Benedict, 1949).
In many species there is such involvement of the father with the offspring that
research emphasizes parental motivation, meaning that both parents desire to participate
in the care of the young (Lynn, 1974). People who believe in a maternal instinct
among human beings should examine the literature on child abuse, which indicates
that both mothers and fathers sometimes behave in diverse and harmful ways toward
their children (Blumberg, 1980).