Cognitive Development in Middle Adulthood

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In middle adulthood, the cognitive demands of
everyday life extend to new and sometimes
more challenging situations
Middle adulthood is a time of expanding
responsibilities – on the job, in the community,
and at home
To juggle diverse roles effectively middle aged
adults call on a wide array of intellectual
abilities
› Including accumulated knowledge, verbal fluency,
memory, rapid analysis of information, reasoning,
problem solving, and expertise in their areas of
specialization
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Widely held stereotypes exist of older adults as
forgetful and confused
› Most cognitive aging research has focused on deficits
while neglecting cognitive stability and gains
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Different aspects of cognitive functioning show
different patterns of change
Although declines occur in some areas, most people
display cognitive competence, especially in familiar
contexts, and some attain outstanding
accomplishment
Some apparent decrements in cognitive aging result
from weaknesses in the research itself
› Overall, the evidence supports an optimistic view of adult
cognitive potential
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Research on cognitive aging in
middle adulthood reflects the
core assumptions of the lifespan
perspective
› Development as multidimensional
 The combined result of biological,
psychological, and social forces
› Development as multidirectional
 The joint expression of growth and
decline, with the precise mix
varying across abilities and
individuals
› Development as plastic
 Open to change, depending on
how a person’s biological and
environmental history combines
with current life conditions
Research using intelligence tests sheds light on the widely held
belief that intelligence inevitably declines in middle and late
adulthood and the brain deteriorates
 Although many early cross-sectional studies showed a peak in
performance at age 35 followed by a steep drop into old age
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To explain this contradiction, K. Warner Schaie used a sequential
design, combining longitudinal and cross-sectional approaches
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BUT… Longitudinal research starting in the 1920s revealed an age-related
INCREASE in performance
Seattle Longitudinal Study
In 1956, people ranging in age from 22-70 were tested cross-sectionally
Then, at regular intervals, longitudinal follow-ups were conducted and
new samples added, yielding a total of 5,000 participants, 5 crosssectional comparisons, and longitudinal data spanning more than 60
years
Results
Findings on 5 mental abilities showed the typical cross-sectional drop
after the mid-30s
› But longitudinal trends for those abilities revealed modest gains in midlife,
sustained into the 50s and the early 60s, after which performance
decreased gradually
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Cohort effects are largely responsible for this difference
In cross-sectional research, each new generation experienced better
health and education than the one before it
› Also, the tests given may tap abilities less often used by older individuals
whose lives no longer require that they learn information for its own sake
but, instead, skillfully solve real-world problems
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Only certain mental abilities follow the longitudinal pattern
in the previous chart
 There are 2 types of intelligence that seem to explain
these findings
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› Crystallized intelligence – skills that depend on accumulated
knowledge and experience, good judgment, and mastery of
social conventions
 Largely influenced by culture
 Measured on intelligence tests by performance on vocabulary,
general information, verbal comprehension, and logical
reasoning
› Fluid intelligence – depends more heavily on basic informationprocessing skills – ability to detect relationships among visual
stimuli, speed of analyzing information, and capacity of working
memory
 Measured on intelligence tests by items involving spatial
visualization, digit span, letter-number sequencing, and symbol
search
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Crystallized intelligence increases steadily through
middle adulthood
Fluid intelligence begins to decline in the 20s
These trends have been found repeatedly in
investigations in which younger and older participants
had similar education and general health, largely
correcting for cohort effects
In one study of 16-85 year olds
› Verbal (crystallized) IQ peaked between ages 45-54 and did
not decline until the 80s
› Nonverbal (fluid) IQ dropped steadily over the entire age
range
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The midlife rise in crystallized abilities makes sense
› Adults are constantly adding to their knowledge and skills at
work, at home, and in leisure activities
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Schaie found that there are 5 factors that gain in
early and middle adulthood: verbal ability, inductive
reasoning, verbal memory, spatial orientation, and
numeric ability
› These factors include both crystallized and fluid skills
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Findings confirmed that middle-aged adults are
intellectually “in their prime”
A 6th ability, perceptual speed, a fluid skill decreased
from the 20s to the late 80s
› A pattern that fits with research indicating that cognitive
processing slows as people get older
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Late in life, fluid factors (spatial orientation, numeric
ability, and perceptual speed) show greater
decrements than crystallized factors (verbal ability,
inductive reasoning, and verbal memory)
Mean Standardized Score
70
60
50
verbal ability
40
inductive reasoning
30
spatial orientation
verbal memory
numeric ability
20
perceptual speed
10
0
25 32 39 46 53 60 67 74 81 88
Age in Years
Some theorists believe that a general slowing of central nervous
system functioning underlies nearly all age-related declines in
cognitive performance
 Many studies show that scores on speeded tasks mirror the
regular, age-related decline in fluid-task performance
 Reasons why fluid intelligence (basic information processing skills)
declines earlier, but crystallized abilities gain and then stabilize
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The decrease in basic processing, while substantial after age 45, may not
be great enough to affect many well-practiced performances until quite
late in life
› Adults can often compensate for cognitive limitations by drawing on their
cognitive strengths
› As people discover that they are no longer as good as they once were
at certain tasks, they accommodate, shifting to activities that depend
less on cognitive efficiency and more on accumulated knowledge
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Ex. The basketball player becomes a coach and the once quickwitted salesperson becomes a manager
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The age trends mask large individual differences
Adults who use their intellectual skills seem to maintain them longer
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In the Seattle study, declines were delayed for people with above-average
education, complex occupations, and stimulating leisure activities that included
reading, traveling, attending cultural events, and participating in clubs and
professional organizations
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i.e. if you don’t use it you lose it
People with flexible personalities, lasting marriages (especially to a
cognitively high-functioning partner), and absence of cardiovascular
and other chronic diseases were likely to maintain mental abilities well
into late adulthood
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i.e., individuals who experience less stress tend to sustain cognitive abilities longer
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Probably because SES is associated with many of the stressful factors mentioned
above
Being economically well-off is linked to favorable cognitive
development
In early and middle adulthood, women outperformed men on verbal
tasks and perceptual speed, while men excelled at spatial skills
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However, overall, changes in mental abilities over the adult years were similar for
men and women
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Cohort effects were evident in comparisons of baby
boomers, now middle-aged, with the previous
generation at the same age
› On verbal memory, inductive reasoning, and spatial
orientation, the baby boom cohort performed
substantially better probably because of generational
advances in education, technology, environmental
stimulation, and health care
› These gains are expected to continue: Today’s children,
adolescents, and adults of all ages attain substantially
higher mental test scores than same-age individuals born
just a decade or two earlier
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Adults who maintained higher levels of perceptual
speed tended to be advantaged in other cognitive
capacities
› Probably because thinking faster allows you to consider
more things in a shorter period of time
Information-processing researchers interested in adult
development usually use this model to guide research on
different aspects of thinking (we went over it in chapter 5)
 As processing speed slows, certain aspects of attention and
memory decline
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Yet, midlife is also a time of great expansion in cognitive competence as
adults apply their vast knowledge and life experiences to problem
solving in the everyday world
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On both simple reaction-time tasks (pushing a butting in
response to a light) and complex reaction-time tasks (pushing a
left-hand button to a blue light and a right-hand button to a
yellow light), response time increases steadily from the early 20s
into the 90s (meaning reaction takes longer)
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The more complex the situation, the more disadvantaged (slower) older
adults are
Researchers agree that changes in the brain cause this agerelated slowing of cognitive processing, but disagree on the
precise explanation
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Neural network view – as neurons in the brain die, breaks in neural
networks occur
 The brain adapts by forming bypasses – new synaptic connections that go
around the breaks but are less efficient
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Information-loss view – suggests that older adults experience greater loss
of information as it moves through the cognitive system
 As a result, the whole system must slow down to inspect and interpret the
information
 Ex. Imagine making a photocopy, then using it to make another copy, each
subsequent copy is less clear
 Similarly, with each step of thinking, information degrades, the older the
adult, the more exaggerated this effect
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Processing speed predicts adults’ performance on many tests of
complex abilities
The slower their reaction time, the lower their scores on memory,
reasoning, and problem-solving tasks
› Relationships are greater for fluid than crystallized-ability items
› This suggests that processing speed contributes broadly to declines in
cognitive functioning
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The correlation between processing speed and other cognitive
performances strengthens with age, but the correlation is only
moderate
 Processing speed is not the only major predictor of age-related
cognitive changes
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Declines in vision and hearing and attentional resources, inhibition,
working-memory, capacity, and use of memory strategies also predict
diverse age-related cognitive performances
Processing speed is a weak predictor of the skill with which older
adults perform complex, familiar tasks in everyday life
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Which they continue to do with considerable proficiency
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Studies of attention focus on:
How much information adults can take into their mental systems at once
The extent to which they can attend selectively, ignoring irrelevant
information
› The ease with which they can adapt their attention, switching from one
task to another as the situation demands
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Research reveals that sustaining 2 complex tasks at once
becomes more challenging with age
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This may be due to the slowdown in information processing speed, which
limits the amount of information a person can attend to at once
As adults get older, inhibition – resistance to interference from
irrelevant information – is also harder
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Which can cause older adults to appear distractible in everyday life
People who are highly experienced in attending to critical
information and performing several tasks at once, such as air
traffic controllers and pilots, show smaller age-related attentional
declines
 Practice can improve older adults’ ability to divide attention
between 2 tasks, selectively focus on relevant information, and
switch back and forth between mental operations
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From the 20s into the 60s, the amount of information
people can retain in working memory diminishes
› Largely because of a decline in use of memory strategies
 Older individuals rehearse less than younger individuals – thought
to be due to slower rate of thinking
 Older people cannot repeat new information to themselves as
quickly as younger people
› Reduced working memory capacity is another likely influence
 Leading to difficulties in retaining to-be-remembered items and
processing them at the same time
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Memory strategies of organization and elaboration, which
require people to link incoming information with already
stored information, are also applied less often and less
effectively with age
› Older adults find it harder to retrieve information from long-term
memory that would help them recall
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Tasks can be designed to help older people compensate
for age-related declines in working memory
› Ex. By slowing the pace at which information is presented or
cueing the link between new and previously stored information
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To understand memory development and other aspects
of cognition in adulthood, we must view them in context
› Assessment in highly structured conditions may substantially
underestimate what older adults remember when they can
pace their own learning
› General factual knowledge (such as historical events),
procedural knowledge ( such as how to drive a car or solve a
math problem), and knowledge related to one’s occupation
either remain unchanged or increase into midlife
› Aging has little impact on metacognitive knowledge, which
middle-aged people use to maximize performance
 Ex. Reviewing major points before an important presentation,
organizing notes and files so information can be found quickly,
and parking the car in the same area of the parking lot each day
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In middle adulthood, gains in expertise occur
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Expertise – an extensive, highly organized, and integrated knowledge
base that can be used to support a high level of performance
Gains in expertise support middle-aged adults’ continued
cognitive growth in practical problem solving – analyzing how to
achieve goals in real-world situations involving a high degree of
uncertainty
 Expertise is seen in individuals in all types of work, not just in those
who are highly educated or work in high-level jobs
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Expertise can develop in any area in any field
Age related advantages are also evident in solutions to
everyday problems
From middle age on, adults place greater emphasis on thinking through
a practical problem – trying to understand it better, interpreting it from
different perspectives, and solving it through logical analysis
› Middle-aged and older adults select problem-solving strategies that are
at least as good as and sometimes better than those of young adults
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Creative accomplishment tends to peak in the late
30s and early 40s and then decline, but with
considerable variation across individuals and
disciplines
The quality of creativity may change with advancing
age in at least 3 ways
› Youthful creativity is often spontaneous and intensely
emotional
 While creative works produced after age 40 often appear
more deliberately thoughtful
› With age, many creators shift from generating unusual
products to combining extensive knowledge and
experience into unique ways of thinking
› Creativity in middle adulthood frequently reflects a
transition from a largely egocentric concern with selfexpression to more altruistic goals aimed at helping
society as a whole
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Cognitive gains in middle adulthood are especially
likely in areas involving experience-based buildup
and transformation of knowledge and skills
› When given challenging real-world problems related to
their area of expertise, middle-aged adults are likely to out
perform younger adults in both efficiency and excellence
of thinking
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By middle adulthood, thinking is characterized by an
increase in specialization as people branch out in
various directions in their life paths
To reach their cognitive potential, adults must have
opportunities for continued growth
› In occupation, leisure activities, and other aspects of their
personal lives
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