Development across the Life Span 331(Mitchell & Locke, 2015). The major source of misinformation began in 1998, when
British gastroenterologist Dr. Andrew Wakefield published the results of two studies that
seemed to link the MMR (measles, mumps, and rubella) vaccine to autism and bowel dis-
ease in children (Wakefield et al., 1998). Experts reviewed the quality of his research, and
the studies were quickly denounced as inadequate and dangerous by autism specialists
and others (Fitzpatrick, 2004; Judelsohn, 2007; Matthew & Dallery, 2007; Novella, 2007;
Stratton et al., 2001a, 2001b). to Learning Objectives 1.8 and 1.9. Nevertheless,
Wakefield’s publication was followed by measles epidemics due to parents refusing the
MMR inoculation for their children. The myth of a link persists, in spite of numerous
studies that have consistently failed to show any link between the MMR vaccine and
autism (Burns, 2010; Gilberg & Coleman, 2000; Johnson & Myers, 2007; Madsen et al.,
2002; Mars et al., 1998; Taylor et al., 1999; Thompson et al., 2007). In 2004, the other
authors listed on the study formally retracted the 1998 paper. In 2009, the final blow came
to Wakefield’s credibility when it was discovered that he had falsified his data, resulting
in the revoking of his medical license in May of 2010 (Meikle & Bosley, 2010).
Psychosocial Development
8.8 Identify the development of personality, relationships, and self-concept in
infancy and childhood.
The psychological and social development of infants and children involves the develop-
ment of personality, relationships, and a sense of being male or female. Although these
processes begin in infancy, they will continue, in many respects, well into adulthood.
Why are some children negative and whiny while others are
sweet and good natured?TEMPERAMENT One of the first ways in which infants demonstrate that they have dif-
ferent personalities (i.e., the long-lasting characteristics that make each person differ-
ent from others) is in their temperament, the behavioral and emotional characteristics
that are fairly well established at birth. Researchers (Chess & Thomas, 1986; Thomas &
Chess, 1977) have identified three basic temperament styles of infants:
- Easy: “Easy” babies are regular in their schedules of waking, sleeping, and eating
and are adaptable to change. Easy babies are happy babies and when distressed are
easily soothed. - Difficult: “Difficult” babies are almost the opposite of easy ones. Difficult babies
tend to be irregular in their schedules and are very unhappy about change of any
kind. They are loud, active, and tend to be crabby rather than happy. - Slow to warm up: This kind of temperament is associated with infants who are less
grumpy, quieter, and more regular than difficult children but who are slow to adapt
to change. If change is introduced gradually, these babies will “warm up” to new
people and new situations.
Of course, not all babies will fall neatly into one of these three patterns—some chil-
dren may be a mix of two or even all three patterns of behavior, as Chess and Thomas
(1986) discovered. Even so, longitudinal research strongly suggests that these temperament
styles last well into adulthood and are strongly influenced by heredity (Kagan, 1998; Kagan
et al., 2007; Korn, 1984; Scarpa et al., 1995; Schwartz et al., 2010), although they are some-
what influenced by the environment in which the infant is raised. For example, a “diffi-
cult” infant who is raised by parents who are themselves very loud and active may not
be perceived as difficult by the parents, whereas a child who is slow to warm up might be
perceived as difficult if the parents themselves like lots of change and noise. The first infant
is in a situation in which the “goodness of fit” of the infant’s temperament to the parents’
temperament
the Dehavioral characteristics that are
fairly well estaDlished at Dirth such as
peasyq pdifficultq and pslow to warm
uR q the enduring characteristics with
which each Rerson is Dorn.