onset of the growth spurt
（i） For females； puberty begins with menarche
（ii） For males； puberty begins with production of live
sperm
（iii） Physical changes often bring an awareness of sexual
feelings
c） Physical changes of adolescence may exaggerate the
adolescent’s concern with their body image； their subjective
view of their appearance
（i） Females seem to have less average confidence in their
physical attractiveness dm do males
（ii） When exaggerated； females preoccupation with body
image and aspects of the social self can lead to self…
destructive behavior； such as eating disorders
（a） Anorexia； involves self…imposed starvation
（b） Bulimia； involves binging and purging
C。 Physical Changes In Adulthood
1。 Some senses may bee less acute
2。 Changes occur gradually
3。 Many physical changes occur as a result of disuse； rather than aging
4。 Some changes are largely unavoidable
a） Visual function diminishes for most people over age 65
（i） Lenses of eyes bee yellowed and less flexible
（ii） Lens rigidity impacts adaptation to dark
b） Hearing loss is mon past age 60
（i） Older adults may have difficulty hearing high…
frequency sounds； with males experiencing more
difficulty than females
（ii） Changes in hearing are gradual and may not be
realized until they are extreme
c） Reproductive and sexual functioning changes
（i） Females experience menopause around age 50
（ii） Quantity of sperm in males decreases after age 40；
and seminal fluid volume declines past age 60
（iii） Increasing age and physical change do not
necessarily impair other aspects of sexual experience
III。 Cognitive Development across the Life Span
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A。 Cognitive development is the study of the processes and products of the mind； as they
emerge and change over time
B。 Piaget’s Insights into Mental Development
1。 Piaget saw the mind as an active biological system； seeking； selecting；
interpreting； and reorganizing environmental information to fit with
or adjust to its own existing mental structures
2。 Piaget’s interest was not in the amount of information children
possessed； but in the ways children’s thinking and inner
representations of outer physical reality changed at different stages in
their development
3。 Schemes are the mental structures enabling the individual to interpret
the world
a） Schemes are the building blocks of development change
b） Piaget characterized infants’ initial schemes as sensorimotor
intelligence
（i） First dependent on physical presence of objects that
could be sucked； watched； or grasped
（ii） Later； mental structures increasingly incorporate
symbolic representations of outer reality
4。 Piaget saw cognitive development as the result of the interweaving of
assimilation and acmodation。 These two processes work in tandem
to achieve cognitive growth
a） Assimilation modifies new environmental information to fit
into what is already known
b） Acmodation restructures or modifies the child’s existing
schemes so that new information is accounted for more
pletely
c） Discrepancies between already held ideas and new
experiences force development of more adaptive inner
structures and processes that permit creative and appropriate
actions to meet future challenges
5。 Stages in Cognitive Development
a） Sensorimotor stage： infancy； roughly from birth to age 2
（i） Child is tied to the immediate environment and
motor…action themes
（ii） Most important cognitive acquisition of infancy is
attainment of object permanence； the ability to form
mental representations of absent objects
b） Preoperational stage： roughly 2 to 7 years of age
（i） Main cognitive advance is improved ability to
mentally represent objects not physically present
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（ii） Piaget characterized this stage in terms of what the
child cannot do； other than the development of
representational thought
（iii） Child’s thoughts at this stage are characterized by
egocentrism； an inability to take the perspective of
another； or to imagine a scene from any perspective
other than one’s own； as demonstrated by Piaget’s
three…mountain task
（iv） Children at this stage have difficulty distinguishing
the mental from the physical world； as demonstrated
by animistic thought
（v） Centration is the tendency to be captivated （centrated）
by the more perceptually striking features of objects
c） Concrete operational stage： roughly ages 7 to 11 years of age
（i） Child is capable of mental operations
（ii） Mastery of conservation is a hallmark of this stage
（iii） Children at this stage generally do not ask abstract
questions； but remain with specifics
d） Formal operational stage： roughly from age 11 on
（i） Represent the final stage of cognitive growth； in
which thinking bees abstract
（ii） Adolescents realize their reality is only one of several
that are imaginable； and begin pondering deeper
questions of truth； justice； and existence
（iii） Individual begins to impose his/her own structures
on tasks； beginning with broad categories； then
formulating and testing hypotheses in light of the
individual’s knowledge of categories and
relationships
C。 Contemporary Perspectives on Early Cognitive Development
1。 Contemporary research posits a greater degree of order； organization；
and coherence in the perceptual and cognitive experience of the infant
and young child than that proposed by Piaget
2。 Recent research shows that differences in conceptual understanding
between preoperational and concrete operational children may be a
difference in immediate memory
a） The sensorimotor child revisited： 3…month…old neonates may
have already developed the concept of object permanence； as
well as being able to integrate information across sensory
domains
b） The preoperational child revisited
（i） Egocentrism may not be ongoing； as recent research
indicates the child to have the ability to take the
perspective of the other if the task is simple
（ii） Children at this stage also have the ability to
differentiate mental and physical worlds； if they are
asked the correct questions
（iii） Recent research indicates the preoperational child is
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not exclusively centrated
3。 Children’s Foundational Theories
a） Recent research explores the notion that changes occur
separately； in several domains； as the child develops
foundational theories； or frameworks for initial
understanding； to explain experiences of the world
b） Children accumulate experiences into a theory of mind；
through performing the functions of psychologists
c） Children must be young practitioners of disciplines such as
physics and biology in order to perfect their understanding of
various aspects of the world
4。 Social and Cultural Influences on Cognitive Development
a） Late in his life； Piaget began to question the cross…cultural
validity of his findings。 Research has since shown that there
are cross…cultural differences in cognitive development。
b） Vygotsky argued that children developed through a process of
internalization； that they absorb knowledge from their social
context。
c） The concept of internalization helps to explain the effect
culture has on cognitive development。
D。 Cognitive Development in Adulthood
1。 Intelligence
a） Only about 5 percent of the healthy elderly experience a major
loss in cognitive functioning
b） Age…related decline in functioning is usually limited to only
some abilities； such as
（i） Difficulty in forming new associations
（ii） Slower acquisition of new information
c） As pared to crystallized intelligence； only fluid
intelligence shows a slight decline with increasing age
d） Wisdom； experience in the fundamental pragmatics of life； may
experience age…related gains
2。 Elderly individuals who pursue high levels of environmental
stimulation tend to maintain high levels of cognitive functioning
a） Disuse； rather than decay； may be responsible for isolated
deficits in cognitive functioning
b） Successful aging may be linked to a strategy of selective
optimization with pensation
（i） Selective means scaling down the number and extent
of goals
（ii） Optimization refers to exercising or training oneself in
areas of individual highest priority
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（iii） pensation means using alternative methods of
dealing with losses； such as choosing age…friendly
environments
3。 Memory
a） Not all memory systems show age…related deficits； general
knowledge store and personal information does not appear to
diminish
b） Older adults do experience difficulty in acquisition of new
information
c） Elderly individuals’ memory performance may be impaired by
their belief that their memory will be poor
d） Certain age…related neurobiological changes may result in
impaired memory：
（i） Loss or decay of cells in the brain
（ii） Deficiencies in neurotransmitters
（iii） Patients with Alzheimer’s disease experience gradual
loss of memory； as well as deterioration of
personality； which
（a） Affects ±5％ of individuals past age 65 and
±20％ of individuals past age 80
（b） Deceptively mild onset
（c） Steady deterioration； including
（d） Gradual personality changes
（e） Inattentiveness and mutism
（f） Lack of ability to care for oneself
（g） Loss of memory for who they are
（h） Eventual death
IV。 Acquiring Language
A。 Most researchers agree that the ability to learn language is biologically based–that it is an
innate capacity
1。 Perceiving Speech and Perceiving Words： A child’s first step in acquiring
language is noting sound contrasts that are used meaningfully in that
language
a） When using signed languages； the child must attend to
contrasts in such things as positions of the hands
b） Minimal meaningful units in speech are phonemes
c） Children habituate to phonemes； learning to distinguish
between different sounds
B。 Learning Word Meanings
1。 Naming explosion occurs