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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. 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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.