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Effects of Physical Activity on Cognition 1
An Investigation into the Effects of Physical Activity on Cognition
Jim Chien-Chun Chen
0277IB Psychology Extended Essay
Ms. B. Patton
May 2013
Word Count: 3973
Effects of Physical Activity on Cognition 2
Abstract
This essay investigates the effects of childhood physical activity on cognition. Childhood
physical activity affects the development of cognitive functions associated with decision making
and social interactions. Hillman et al.‟s (2009) findings suggest that children with high aerobic
fitness are more accurate when computing executive function tasks which require the use of
multiple cognitive processes. However, children with low aerobic fitness also improve in
executive functions as their physical activity level rise (Davis et al., 2011). Cognitive
development involves both cognitive processing and social cognitive development. Bean et al.
(2012) linked physical activity to social skills and showed that increased levels of physical
activity provide immediate increase in self-efficacy, which help children deal with challenges as
they have more confidence in their choices and abilities.
Elderly physical activity as a preventative factor against cognitive impairment has been
thoroughly investigated (Middleton & Yaffe, 2009). However, the effects of a potential cognitive
reserve provided by physical activity, which suggests physical activity during childhood to
prevent elderly cognitive impairment, have not been radically explored. Middleton et al.‟s (2010)
study supported the theory of a cognitive reserve as it found that physical activity during teenage
years appears to be the strongest protective factor against cognitive impairment in later life
compared to physical activity throughout the lifetime.
This investigation of the effect of physical activity on cognition produced convincing
evidence that childhood physical activity yield immediate improvements to cognitive processes
and prevents cognitive impairment in later life.
Word Count: 233
Effects of Physical Activity on Cognition 3
Table of Contents
Introduction ..................................................................................................................................... 4
Physical Activity‟s Effects on Cognitive Development ................................................................. 5
Aerobic Fitness Influences Decision Making ............................................................................. 6
Physical Activity also Benefits Overweight Children................................................................. 8
Physical Activity and Interpersonal Skills ................................................................................ 10
Physical Activity‟s Effects on Cognitive Impairment .................................................................. 13
The Cognitive Reserve .............................................................................................................. 13
Physical Activity and Dementia ................................................................................................ 15
Conclusion .................................................................................................................................... 17
References ..................................................................................................................................... 20
Appendix A ................................................................................................................................... 25
Appendix B ................................................................................................................................... 26
Effects of Physical Activity on Cognition 4
Introduction
Physical activity refers to any bodily movement produced by skeletal muscles that
requires energy expenditure. In a recent study in the August issue of Obesity Reviews, a study
conducted by Barry Popkin and Shu Wen Ng from the University of North Carolina evaluated
the worldwide decline in physical activity. The study analyzed data dating back to the 1960s and
found physical activity levels are at an all-time low in countries across the world, namely, the
United States, China, India, Brazil and the United Kingdom. The results are in line with National
Institutes of Health surveys which found child obesity rates tripling in the past two decades
(Edwards, 2008). In their research, Barry Popkin and Shu Wen Ng attributes the lack of physical
activity to the continual integration of technology into children‟s daily lives. However, the
problem may have occurred long before children gained access to technology. In a 2009 study
published by the Alliance of Childhood found that kindergarten students in Los Angeles and New
York City are spending six times as long on language and mathematics than playing. Children
and students are reducing the time spent playing and being active to better themselves
academically. Meanwhile the United States College Board revealed that in 2011, SAT reading
scores reached an all-time low and that reading and math combined scores fell to their lowest
since 1995. The reduction of physical activity and lack of success academically could very well
be connected, as physical activity is associated with enhanced cognitive development. The
present essay therefore investigates the effects of physical activity on cognitive development.
Childhood physical activity may not only affect the children now but also be indicative of
the future. From 2002 to 2006 the U.S. Department of Health and Human Services‟ Centers for
Disease Control and Prevention funded a national, multicultural, social marketing campaign
called VERB. The VERB campaign was focused among youth aged 9-13, using marketing
Effects of Physical Activity on Cognition 5
strategies to promote physical activity. Upon the completion of the campaign, researchers, led by
Marian Huhman, seek to find the effectiveness of this campaign. The research conducted by Dr.
Huhman of the University of Illinois published in the American Journal of Public Health found
that the VERB campaign was successful in influencing physical activity in youth aged 9-13;
however, perhaps the more interesting finding was that VERB continued to motivate children to
be physically active during teen age. Similar findings can be found in a 21 year longitudinal
study published in the American Journal of Preventive Medicine. The study concludes that
“school age physical activity appears to influence adult physical activity” (Telama et al., 2005).
The results of these studies indicate that physical activity during childhood not only has an effect
during childhood but also later in life. When discussing the effects of physical activity it is
important to consider not only its effect on cognitive development but also its influences on
cognitive impairment and diseases associated with such impairment. The present essay will not
only discuss the implications on cognitive development associated with physical activity but also
cognitive impairment, and more specifically, the research question is: What are the effects of
childhood physical activity on cognition over the life course?
Physical Activity’s Effects on Cognitive Development
Physical activity provides many health benefits but with standardized test scores
dropping in the United States (Chandler, 2011), some educators asked by the NY Times believe
time is better spent on academic courses (Park, 2012). However, physical activity is not only
beneficial to one‟s physical health as many studies have found cognitive development to be
positively influenced by physical activity.
Effects of Physical Activity on Cognition 6
Aerobic Fitness Influences Decision Making
In 1997, a meta-analysis was conducted by a group of researchers led by Jennifer Etnier
of Arizona University. This meta-analysis analyzed nearly 200 studies on the impact that
exercise has on cognition. The study found mixed results and most studies analyzed were that of
adults. In 2009, Hillman, Buck, Themanson, Pontifex, and Castelli suggested that there is a
scarcity of research of that relationship in children. With this in mind, Charles Hillman and his
researchers from the University of Illinois conducted a research on the correlation between
aerobic fitness and cognitive development, specifically executive control functions. Executive
control refers to a goal-oriented activity that requires the use of different computational
processes involved in perception, memory and action (Meyer & Kieras, 1997). The study
assessed 38 higher- and lower-fit children. The qualification of higher- and lower-fit was
determined by the Pacer Test. The Pacer test is a multi-stage test involving 20 meter shuttle runs.
It is a test commonly used as a measure for fitness (Alvers, 2011). The researchers chose not to
use the body mass index as the measure of fitness since the body mass index only accounts for
weight and height and not fitness levels. The experiment had the same number of each gender in
the two experimental groups, to eliminate the potential for gender differences to skew the results.
The researchers also eliminated baseline differences in cognition by implementing tests of
intelligence quotient, language skills and more. The results of these tests are fairly similar across
the two groups. The full list of results can be seen in Table 1 on the next page.
Effects of Physical Activity on Cognition 7
Table 11
The participants‟ task involves completing a cognitive flanker task called the Eriksen
flanker task. The Eriksen flanker task requires subjects to respond as quickly as possible to the
letter presented on a computer. The task involved a string of letters either congruent (i.e.
HHHHH) or incongruent (i.e. HHSHH). The task involves simple but multiple cognitive
processes. The subjects must identify the letters presented, apply the definition of congruent and
incongruent, recognize the pattern, and then provide a response. The results found that the
higher-fit children performed more accurately across all conditions of the flanker task compared
to the lower-fit children. However, no differences in reaction time were observed. The reason for
such can be seen with the brain scans conducted during the study. Using electroencephalogram
recordings, the researchers observed that higher-fit children showed reduced error negativity,
exhibiting higher self-confidence. The research concluded that “fitness is associated with better
cognitive performance” (Hillman et al., 2009). The electroencephalogram recordings revealed
1
Hillman, C., Buck, S., Themanson, J., Pontifex, M., & Castelli, D. (2009). Aerobic fitness and cognitive
development: Event-related brain potential and task performance indices of executive control in
preadolescent children.. Developmental Psychology, 45(1), 114-129. Retrieved July 18, 2012, from the
PsychINFO database.
Effects of Physical Activity on Cognition 8
that the higher-fit children‟s increased accuracy when responding to the executive control task is
that they showed greater allocation of attentional resources which allows them to more
accurately compute the flanker task. The more accurate cognitive function subsequently results
in a reduction in conflict during response selection. The reduction in conflicts makes it less likely
that the response is wrong. Despite the numerous evidence presented, the study does have
limitations. Namely, there is no way in determining whether the increased accuracy is due to the
higher fitness level or another factor entirely, which makes it difficult to generalize the results to
everyone that exhibits a high fitness level. The researchers attempted to eliminate these
confounding variables by measuring other factors that could influence cognitive performance
such as intelligence. Those factors “have been found to relate to fitness or cognition” (Hillman et
al., 2009) and have been controlled so the validity of the experiment should not suffer due to
other potentially confounding variables. The study supports that physical fitness is associated
with an increase of cognitive development during childhood.
Physical Activity also Benefits Overweight Children
The study by Hillman et al. (2009) supports a differentiation in cognitive performance
between higher- and lower-fit children. However, it does not provide evidence to suggest that
this difference is due to physical activity and not simply fitness levels. Some children may not be
physically active but would be considered fit due to better metabolism. This caveat is addressed
in a recent study led by Catherine Davis of the Medical College of Georgia and published by the
American Psychological Association (2011). The study aims to test the hypothesis of whether
physical activity would improve cognitive functions in overweight children. The participants
chosen are overweight 7 to 11 year old children as defined by the BMI. The choice of the BMI
would be appropriate in this case because the study is concerned with weight and not fitness. The
Effects of Physical Activity on Cognition 9
participants were then sorted into three groups: the control; the low-dose, which required 20
minutes of physical activity per day; and the high-dose, which required 40 minutes of physical
activity per day. All participants were post-tested 13 weeks after the implementation of the
exercise programs using the Cognitive Assessment System and the Woodcock-Johnson Test of
Achievement III. A table of what the test assesses can be found in Appendix A. It is revealed
from the results that between the 3 exercise groups, the high-dose group achieved over 3 points
higher in the executive function test and the math achievement test. The differences between the
control group and the low-dose group were less significant but apparent nonetheless. A graphic
summarizing the results of the tests can be seen in Table 2.
Table 22
2
Davis, C., Tomporowski, P., McDowell, J., Austin, B., Miller, P., Yanasak, N., et al. (2011). Exercise improves
executive function and achievement and alters brain activation in overweight children: A randomized,
controlled trial.. Health Psychology, 30(1), 91-98. Retrieved July 18, 2012, from the PsychINFO database.
Effects of Physical Activity on Cognition 10
Aside from the cognitive assessments, the researchers approached the research
biologically as well with fMRI scans of the subjects‟ brain. Preliminary results showed stronger
bilateral prefrontal cortex activity in the high-dose group when compared to the control group.
The prefrontal cortex is responsible for executive functions; therefore the biological results are
congruent with the cognitive test results. The strength of this study lies in its ability to produce a
dose-response effect, similar to a cause-effect relationship. In the current study, the doses of
physical activity exposure are none, 20 minutes per day, and 40 minutes per day. Using a doseresponse relationship, a clear positive correlation can be seen with physical activity and cognitive
achievement and addresses a significant limitation with the Hillman et al.‟s (2009) study. A
dose-response relationship provides more support that the increase in cognitive development is
due to the exercise program by using multiple groups. However, Davis et al.‟s (2011) research
only examined overweight children, which limits the studies generalizability to all children that
exercise, since it is only hypothetical that the same relationship will be present with nonoverweight children. However, generalizations may not be needed as studies like Hillman et al.‟s
(2009) have shown that children of higher fitness already exhibit better cognitive functions
without additional exercise. Davis et al. (2011) also pointed to a “remarkable” improvement in
math achievement, because no additional mathematical skills were taught to any of the 3 groups.
Mathematics involves abstract concepts and according to Piaget‟s schema theory on cognitive
development, abstract concepts represent a higher level of cognitive development.
Physical Activity and Interpersonal Skills
Cognitive development is not only in academic fields but also in self and interpersonal
skills. In a recent review of psychological research, it was found that physical activity
intervention had a positive effect on self-efficacy (Lewis et al., 2002), however the same result
Effects of Physical Activity on Cognition 11
was not found in African American adolescent (Martin & McCaughtry, 2008). Furthermore,
Trost, Pate, and Ward (1999) found that the correlation could only be seen in boys when they
conducted a study involving sixth grade students of both gender. The lack of evidence that
physical activity has a positive effect on self-efficacy of African-American adolescent girls is
addressed in a recent study by Bean, Miller, Suzanne, Mazzaeo, and Fries (2012) suggesting that
the positive effects of physical activity on social skills is beyond what previous research has
discovered. The study involved 90 girls of which 71% were African Americans participating in a
physical activity program called Girls on the Run. The girls were tested before enrolling in the
program with a MANOVA test, which analyzed the correlation between social cognitive
constructs and physical activity frequency. The girls are then tested following the conclusion of
the program and then 3-months thereafter. From the results of the MANOVA tests, there were
moderate increases in social influence and self-efficacy during post-test and sustained during a 3
month follow up test. Social influence in this case refers to the leadership qualities of an
individual, while self-efficacy refers to her confidence in her choices and opinions which allows
her to overcome challenges. It appears that the Girls on the Run program also increased the
physical activity frequency of the participants 3 months after the program concluded. The full set
of raw data can be seen in Table 3 on the next page.
Effects of Physical Activity on Cognition 12
3
The study establishes clear benefits in two areas of the social cognitive construct: selfefficacy and social influence. The improvements are consistent and long term as seen by the
post-test and the 3 months followup test. However, the study is not without its weaknesses. One
of which is the fact that the data are self-reported, which could lead to social desirability bias in
the participants‟ responses and skew the results. There aren‟t many ways in which the
researchers could control the potential bias, since measuring 50 participants‟ physical activity at
all points throughout the study is unrealistic. But the research had an ample sample size, which
would decrease the effect of some incorrectly reported physical activity levels.
The study by Hillman et al. (2009) established a positive correlation between fitness and
executive functions. Davis et al. (2011) explored the benefits of physical activity within a
3
Bean, M., Miller, S., Mazzeo, S., & Fries, E. (2012). Social cognitive factors associated with physical activity in
elementary school girls.. American Journal of Health Behavior, 36(2), 265-274. Retrieved July 18, 2012,
from the PsychINFO database.
Effects of Physical Activity on Cognition 13
physically disadvantaged group and the same results were observed, which supports that
executive functions is not only affected by fitness levels but also physical activity levels. In
support of existing studies, Bean et al. (2012) found that physical activity benefitted children‟s
social cognitive development as defined by the social cognitive thoery. The studies support that
physical activity not only benefits children‟s health but also has a positive effect on cognitive
development.
Physical Activity’s Effects on Cognitive Impairment
Many studies supported the positive effects physical activity has on cognitive
development, furthermore, physical activity is also seen as one of the most influential factors in
decreasing the risk of cognitive impairment during old age (Middleton & Yaffe, 2009).
Especially physical activity when young, as that seems to directly correlate with adult physical
activity (Telama et al., 2005). With the rise of dementia patients in coming years (Moore, 2007),
ways of reducing cognitive impairment becomes ever more paramount.
The Cognitive Reserve
Many studies have examined physical activity and its effects on cognitive impairment in
elderly people (Dik et al., 2003). Comparatively, few studies have analyzed physical activity
earlier in life and its effect on cognitive impairment later in life. In a study by Scarmeas and
Stern (2003) it suggests that it is possible that “early-life physical activity – similar to early-life
education – could help to build a „cognitive reserve‟ that has long-lasting benefits” (Middleton et
al., 2010). In a cross-sectional study, Middleton, Barnes, Lui, and Yaffe (2010) surveyed 9395
American women aged 65 and older on their physical activity at teen age, age 30, age 50 and
late-life. 9344 of the subjects surveyed completed a Mini-Mental State Examination (MMSE) to
Effects of Physical Activity on Cognition 14
examines subjects‟ orientation, registration, attention, claculation, recall and language which
provided a point based score on if or how severe do the subjects‟ exhibit cognitive deficiencies.
The test and the breakdown of scores can be found in Appendix B. Cognitive Impairment was
present in 16.7% of participants whom were inactive during teenage, and only 8.5% prevelence
rate if active during teenage. This represented the greatest difference across all age groups. In all
other age groups, physical activity is continually associated with lower odds of cognitive
impairment for elderly women. A detailed table of the results can be seen in Table 44. The
unadjusted column uses the inactive participants as reference to display the results. This means
that if the women whom were inactive during teen age are certain to develop cognitive
impairment diseases, the women whom are active during teenage has a 46% chance of cognitive
impairment. The adjusted columns takes into account pre-existing conditions that could affect
the likelihood of the participant developing cognitive deficiencies.
4
Middleton, L., Barnes, D., Lui, L., & Yaffe, K. (2010). Physical activity over the life course and its association
with cognitive performance and impairment in old age.. Journal of the American Geriatrics Society, 58(7),
1322-1326. Retrieved July 18, 2012, from the PsychINFO database.
Effects of Physical Activity on Cognition 15
The data of the study supports that physical activity throughout the lifetime, and most
importantly during teen age would act as a preventative factor against cognitive impairment.
However, there are several weaknesses with the present study. Firstly, physical activity across all
stages of life were self-reported, leading to a potential that the data collected are inaccurate. The
researchers attempted to address this by having a very large sample size. By having a large
sample size, the inaccurate reports would have minimal impact on the findings of the study.
Secondly, some participants are characterized as having cognitive impairment diseases, which
would likely impair their ability to recall their physical activity levels. The study accounted for
such problems by having an adjusted column as explained previously. This study provides
evidence that late life cognitive impairment can be significantly reduced by physical activity
when young, thus physical activity is not only affecting developing children but also their future.
Physical Activity and Dementia
The previous study analyzed only elderly women and whether the results can be
generalized to men is unclear. Laurin, Verreault, Lindsay, MacPherson, and Rockwood (2001)
explored the association between physical activity and cognitive impairment. Even though the
study only studied elderly physical activity, findings have shown being active during old age to
be linked to being physically active at earlier life stages (Del Castillo et al., 2010; Telama et al.,
2005). The present study by Laurin et al. (2001) identified 6434 elderly subjects who were
cognitively normal at baseline. The reaseachers conducted a 5-year followup, due to various
reasons such as refusal to participate or death, the sample during the 5 year follow-up was
reduced to 4615 subjects. Of these 4615, 3894 were not impaired while the other 721
experienced cognitive impairment, or dementia. The participants were divided into none, low,
moderate, and high physical activity groups. The participants without cognitive impairment
Effects of Physical Activity on Cognition 16
consisted of 30%, 13%, 37% and 20% of the total participants respectively. While most groups
showed a decrease in the percentage composition in the subjects with impairment or dementia
compared to the control group without cognitive deficiencies, the no physical activity group
showed an increase from 30% composition of the control group to 44% composition of the
impairment and dementia group. The inactive group did have the second most total participants
of any group at 1103. However, moderate physical activity group had the highest number of
participants at 1360 but only accounted for 31% of study population that developed cognitive
impairment or dimentia. Gender also appears to have no effect on cognitive impairment or
dementia. As the percentage of male and female in the control, subject with cognitive
impairment-no dementia, and subjects with dimentia remained relatively constant with less than
2% change across all three conditions. Therefore, there is ample evidence to support that gender
does not affect cognitive impairment. A table which summarizes the results can be seen in Table
55.
5
Laurin, D., Verreault, R., Lindsay, J., MacPherson, K., & Rockwood, K. (2001). Physical Activity and Risk of
Cognitive Impairment and Dementia in Elderly Persons. Archives of Neurology, 58(3), 498-504.
Effects of Physical Activity on Cognition 17
The study produced similar findings to Middleton et al. (2010). The protective factor of
physical activity against cognitive impairment may also be more significant than the results show:
According to the researchers, of the deceased subjects, most reported low levels of physical
activity at baseline and thus could‟ve developed cognitive impairment and associated diseases
before death. Laurin et al.‟s (2001) study had a limitation in that it is over 10 years old. Since this
study was published, researchers have found that diabetes is a key indicator of cognitive
impairment diseases (Luchsinger, 2008). The study fails to control this variable as it was not
discovered yet. However, it would suggest that physical activity is a protective factor for
cognitive impairment in elderly people as physical activity is a protective factor against diabetes
(Helmrich et al., 1991). The large sample size should dispel the effects of congenital diabetes on
the results. Therefore, Laurin et al.‟s (2001) study provides significant and convincing results
that despite some weaknesses support the claim that physical activity acts as a protective factor
against cognitive impairment.
Physical activity supports cognitive development but also has a lasting effect in
preventing cognitive impairment. The two large scale cross-sectional studies indicated similar
results despite being conducted 9 years apart: 2001 and 2010. The two studies were also
conducted in different countries. The differences in the two studies provide basis for the
generalizability of the results. Therefore, physical activity can optimize cognition and curtail the
risks of cognitive impairment.
Conclusion
Proper levels of physical activity during childhood can have a substantial positive impact
on cognitive development. More accurate executive functions were exhibited by high fitness
Effects of Physical Activity on Cognition 18
children (Hillman et al., 2009). However, improvements were shown with physical activity
regardless of the fitness of the children. The research by Davis et al (2011) exhibited a doseresponse relationship, in which high levels of physical activity resulted in more significant
cognitive development compared to low levels of physical activity. Further research could
explore this relationship and investigate whether there comes a point at which excessive physical
activity no longer improves cognitive functions. Perhaps there is a level at which it may actually
be detrimental to the individual. Due to ethical considerations, having subjects perform excessive
physical activity would be unethical. Many studies presented suggest an immediate impact on
cognition as opposed to a long-term improvement in cognitive development. It would be
interesting to observe the long term effects of physical activity and whether the immediate
improvement is sustained, recessed or furthered.
Childhood physical activity is experimentally determined by Middleton et al. (2010) and
Laurin et al. (2001) to be a strong indicator of cognitive impairment. The strongest even, in one
study‟s results. The effect of childhood physical activity may be associated with the cognitive
reserve theory, which has been the subject of much psychological research. But not many have
analyzed this theory in relation to physical activity. The approach of these studies differed from
those which sought the effects on cognitive development. The studies by Middleton et al. (2010)
and Laurin et al. (2001) were longitudinal studies that used self-reported long term physical
activity as the main source of data. To have available measured data of the large number of
participants in these studies is very challenging and resource intensive; however, data could have
been collected over the course of the studies‟ period. Instead in the case of the Middleton et al.
(2010) study, the subjects must recall their childhood physical activity levels, and their
recollection may not be entirely accurate.
Effects of Physical Activity on Cognition 19
There are still many unresolved questions involving the relationship between physical
activity and cognition, such as the validity of a cognitive reserve, the long term effects of
physical activity on cognitive development and to what extent can the dose-response effect
presented by Davis et al. (2009) be applied. Since cognitive studies are limited to the observation
of behaviour and thus difficult to determine cause, further research should also approach the
topic biologically, specifically in the case of cognitive impairment, since biological studies may
be able to identify biological changes in the brain brought about by physical activity. That being
said, convincing evidence provided by a number of cognitive studies has shown that childhood
physical activity leads to an improvement in cognitive functions at all points in life.
Effects of Physical Activity on Cognition 20
References
Alvers, E. (2011, March 11). Relationship Between Heart Rate & Vo2 Max. Livestrong.
Retrieved August 22, 2012, from http://www.livestrong.com/article/79469-relationshipbetween-heart-rate-/
Bandura, A., & Schunk, D. (1981). Cultivating competence, self-efficacy and intrinsic interest
through proximal self- motivation. Journal of Personality and Social Psychology, 41,
586-598.
Bean, M., Miller, S., Mazzeo, S., & Fries, E. (2012). Social cognitive factors associated with
physical activity in elementary school girls.. American Journal of Health Behavior,
36(2), 265-274. Retrieved July 18, 2012, from the PsychINFO database.
Centers for Disease Control and Prevention. (n.d.). VERB: CDC's Youth Campaign. Centers for
Disease Control and Prevention. Retrieved July 19, 2012, from
http://www.cdc.gov/youthcampaign/
Chandler, M. (2011, September 14). SAT reading scores drop to lowest point in decades.
Washington Post. Retrieved July 20, 2012, from
http://www.washingtonpost.com/local/education/sat-reading-scores-drop-to-lowestpoint-in-decades/2011/09/14/gIQAdpoDTK_story.html
Davis, C., Tomporowski, P., McDowell, J., Austin, B., Miller, P., Yanasak, N., et al. (2011).
Exercise improves executive function and achievement and alters brain activation in
overweight children: A randomized, controlled trial.. Health Psychology, 30(1), 91-98.
Retrieved July 18, 2012, from the PsychINFO database.
Effects of Physical Activity on Cognition 21
Del Castillo, J. M., Navarro, J. E., Sanz, J. L., Rodriguez, M. M., Izquierdo, A. C., & Hierro
Pines, D. D. (2010). Being physically active in old age: Relationships with being active
earlier in life, social status and agents of socialisation.. Ageing & Society, 30(7), 10971113. Retrieved July 18, 2012, from the PsychINFO database.
Dik, M., Deeg, D., & Visser, M. (2003). Early life physical activity and cognition at old age..
Journal of clinical and experimental neuropsychology, 25, 643-653.
Etnier, J., Salazar, W., Landers, D., Petruzzello, S., Han, M., & Nowell, P. (1997). Journal of
Sport & Exercise Psychology. Journal of Sport & Exercise Psychology, 19(3), 149-177.
Helmrich, S., Ragland, D., Leung, R., & Paffenbarger, R. (1991). Physical Activity and Reduced
Occurrence of Non-Insulin-Dependent Diabetes Mellitus. The New England Journal of
Medicine, 325, 147-152. Retrieved August 23, 2012, from
http://www.nejm.org/doi/full/10.1056/NEJM199107183250302
Hillman, C., Buck, S., Themanson, J., Pontifex, M., & Castelli, D. (2009). Aerobic fitness and
cognitive development: Event-related brain potential and task performance indices of
executive control in preadolescent children.. Developmental Psychology, 45(1), 114-129.
Retrieved July 18, 2012, from the PsychINFO database.
Huhman, M., Potter, L., Nolin, M. J., Piesse, A., Judkins, D., Banspach, S., et al. (2010). The
influence of the VERB campaign on children’s physical activity in 2002 to 2006..
American Journal of Public Health, 100(4), 638-645. Retrieved July 18, 2012, from the
PsycINFO database.
Laurin, D., Verreault, R., Lindsay, J., MacPherson, K., & Rockwood, K. (2001). Physical
Activity and Risk of Cognitive Impairment and Dementia in Elderly Persons. Archives
of Neurology, 58(3), 498-504.
Effects of Physical Activity on Cognition 22
Lewis, B., Marcus, B., Pate, R., & Dunn, A. (2002). Psychosocial mediators of physical activity
behavior among adults and children.. American Journal of Preventive Medicine, 23(2),
26-35.
Luchsinger, J. (2008). Adiposity, hyperinsulinemia, diabetes and Alzheimer’s disease: An
epidemiological perspective.. European Journal of Pharmacology, 585, 119-129.
Martin, J., & McCaughtry, N. (2008). Using Social Cognitive Theory to predict physical activity
in inner-city African American school children.. Journal of Sport & Exercise
Psychology, 30, 378-391.
Mather, N., & Woodcock, R. W. (2001). Woodcock-Johnson III tests of achievement: examiner's
manual. Itasca, IL: Riverside Pub..
McLeod, S. (n.d.). Piaget- Cognitive Theory. Simply Psychology - Psychology Articles for
Students. Retrieved August 31, 2012, from
http://www.simplypsychology.org/piaget.html#schema
Meyer, D., & Kieras, D. (1997). A Computational Theory of Executive Cognitive Process and
Multiple- Task Performance: Part 2.. Psychological Review, 104(4), 749-791.
Middleton, L., & Yaffe, K. (2009). Promising strategies for the prevention of dementia..
Archives of Neurology, 66(10), 1210-1215.
Middleton, L., Barnes, D., Lui, L., & Yaffe, K. (2010). Physical activity over the life course and
its association with cognitive performance and impairment in old age.. Journal of the
American Geriatrics Society, 58(7), 1322-1326. Retrieved July 18, 2012, from the
PsychINFO database.
Moore, A. (2007). Older people. We can work it out.. Health Service Journal, 117, 24-26.
Effects of Physical Activity on Cognition 23
Northeast Health Care Quality Foundation. (n.d.). Mini-Mental State Examination (MMSE).
MMSE. Retrieved October 26, 2012, from
www.mhpcn.ca/uploads/MMSE.1276128605.pdf
Park, A. (2012, January 16). The Reason for Recess: Active Children May Do Better in School.
Time.com. Retrieved July 20, 2012, from
http://www.time.com/time/magazine/article/0,9171,2103732,00.html
Popkins, B., & Ng, S. W. (2012). Time use and physical activity: a shift away from movement
across the globe. Obesity Reveiws, 13(8), 659-680. Retrieved August 29, 2012, from
http://onlinelibrary.wiley.com/doi/10.1111/j.1467-789X.2011.00982.x/references
Portero, A. (2011, September 15). Standardized Testing: Is it a Blessing or Curse for U.S.
Students?. International Business Times. Retrieved August 22, 2012, from
http://www.ibtimes.com/articles/214341/20110915/sat-scores-math-reading-collegeboard-standardized-tests.htm
Scarmeas, N., & Stern, Y. (2003). Cognitive reserve and lifestyle. Journal of clinical and
experimental neuropsychology, 25, 625-633.
Telama, R., Yang, X., Viikari, J., Valimaki, I., Wanne, O., & Raitakari, O. (2005). Physical
activity from childhood to adulthood. American Journal of Preventive Medicine, 28(3),
267-273.
Trost, S., Pate, R., & Ward, D. (1999). Correlates of objectively measured physical activity in
preadolescent youth.. American Journal of Preventive Medicine, 17(2), 120-126.
UNC News. (2012, June 14). First study of its kind finds rapid declines in worldwide physical
activity. UNC News. Retrieved August 23, 2012, from
http://uncnews.unc.edu/content/view/5377/107/
Effects of Physical Activity on Cognition 24
World Health Oraganization. (n.d.). Physical Activity. World Health Organization. Retrieved
August 23, 2012, from www.who.int/topics/physical_activity/en/
Effects of Physical Activity on Cognition 25
Appendix A
Effects of Physical Activity on Cognition 26
Appendix B
Mini-Mental State Examination (MMSE)
Patient‟s Name:
Date:
Instructions: Ask the questions in the order listed. Score one point for
each correct response within each question or activity.
Maximum
Score
Patient’s
Score
Questions
5
“What is the year? Season? Date? Day of the week? Month?”
5
“Where are we now: State? County? Town/city? Hospital? Floor?”
3
The examiner names three unrelated objects clearly and slowly, then
asks the patient to name all three of them. The patient‟s response is
used for scoring. The examiner repeats them until patient learns all of
them, if possible. Number of trials:
5
“I would like you to count backward from 100 by sevens.” (93, 86, 79,
72, 65, …) Stop after five answers.
Alternative: “Spell WORLD backwards.” (D-L-R-O-W)
3
“Earlier I told you the names of three things. Can you tell me what those
were?”
2
Show the patient two simple objects, such as a wristwatch and a pencil,
and ask the patient to name them.
1
“Repeat the phrase: „No ifs, ands, or buts.‟”
3
“Take the paper in your right hand, fold it in half, and put it on the floor.”
(The examiner gives the patient a piece of blank paper.)
1
“Please read this and do what it says.” (Written instruction is “Close
your eyes.”)
1
“Make up and write a sentence about anything.” (This sentence must
contain a noun and a verb.)
“Please copy this picture.” (The examiner gives the patient a blank
piece of paper and asks him/her to draw the symbol below. All 10
angles must be present and two must intersect.)
1
30
TOTAL
(Adapted from Rovner & Folstein, 1987)
Effects of Physical Activity on Cognition 27
Instructions for administration and scoring of the MMSE
Orientation (10 points):
• Ask for the date. Then specifically ask for parts omitted (e.g., "Can you also tell me
what season it is?"). One point for each correct answer.
• Ask in turn, "Can you tell me the name of this hospital (town, county, etc.)?" One
point for each correct answer.
Registration (3 points):
• Say the names of three unrelated objects clearly and slowly, allowing approximately one
second for each. After you have said all three, ask the patient to repeat them. The
number of objects the patient names correctly upon the first repetition determines the
score (0-3). If the patient does not
repeat all three objects the first time, continue saying the names until the patient is able
to repeat all three items, up to six trials. Record the number of trials it takes for the
patient to learn the words. If the patient does not eventually learn all three, recall cannot
be meaningfully tested.
• After completing this task, tell the patient, "Try to remember the words, as I will ask
for them in a little while."
Attention and Calculation (5 points):
• Ask the patient to begin with 100 and count backward by sevens. Stop after five
subtractions (93,
86, 79, 72, 65). Score the total number of correct answers.
• If the patient cannot or will not perform the subtraction task, ask the patient to spell the
word "world" backwards. The score is the number of letters in correct order (e.g., dlrow=5,
dlorw=3).
Recall (3 points):
• Ask the patient if he or she can recall the three words you previously asked
him or her to remember. Score the total number of correct answers (0-3).
Language and Praxis (9 points):
• Naming: Show the patient a wrist watch and ask the patient what it is. Repeat with a
pencil. Score one point for each correct naming (0-2).
• Repetition: Ask the patient to repeat the sentence after you ("No ifs, ands, or buts.").
Allow only one trial. Score 0 or 1.
• 3-Stage Command: Give the patient a piece of blank paper and say, "Take this paper in
your right hand, fold it in half, and put it on the floor." Score one point for each part of
the command correctly executed.
• Reading: On a blank piece of paper print the sentence, "Close your eyes," in letters
large enough for the patient to see clearly. Ask the patient to read the sentence and do
what it says. Score one point only if the patient actually closes his or her eyes. This is
not a test of memory, so you may prompt the patient to "do what it says" after the
patient reads the sentence.
• Writing: Give the patient a blank piece of paper and ask him or her to write a sentence
Effects of Physical Activity on Cognition 28
•
for you. Do not dictate a sentence; it should be written spontaneously. The sentence
must contain a subject and a verb and make sense. Correct grammar and punctuation
are not necessary.
Copying: Show the patient the picture of two intersecting pentagons and ask the patient
to copy the figure exactly as it is. All ten angles must be present and two must intersect
to score one point. Ignore tremor and rotation.
Interpretation of the MMSE
Method
Score
Single Cut-off
<24
Abnormal
<21
Increased odds of dementia
>25
Decreased odds of dementia
21
Abnormal for 8th grade education
<23
Abnormal for high school education
<24
Abnormal for college education
Range
Education
Severity
Interpretation
24-30
No cognitive impairment
18-23
Mild cognitive impairment
0-17
Severe cognitive impairment
Sources:
•
Crum RM, Anthony JC, Bassett SS, Folstein MF. Population-based norms for the
mini-mental state examination by age and educational level. JAMA.
1993;269(18):2386-2391.
•
Folstein MF, Folstein SE, McHugh PR. "Mini-mental state": a practical method for grading the
cognitive state of patients for the clinician. J Psychiatr Res. 1975;12:189-198.
•
Rovner BW, Folstein MF. Mini-mental state exam in clinical practice. Hosp Pract. 1987;22(1A):99,
103, 106, 110.
•
Tombaugh TN, McIntyre NJ. The mini-mental state examination: a comprehensive review. J Am
Geriatr Soc. 1992;40(9):922-935.