education

Why does humanity get smarter and smarter?

Intelligence tests have to be adjusted all the time because people score higher and higher. If the average human of today went 105 years back in time, s/he would score 130, be considered as gifted, and join clubs for highly intelligent people. How can that be?

IQ_increase_base_graphic_v.2_EnglishThe IQ growth

The picture above shows the development of humanity’s intelligence between 1909 and 2013. According to IQ-scores people got smarter and smarter. During the last 105 years, people’s scores increased by as much as 30 IQ-points. That is equivalent to the difference between intellectual disability and normal intelligence. Ever since the discovery of this effect by James Flynn, the underlying reason has been hotly debated. A new analysis combines all available studies into one overall picture in order to find answers.

Jakob Pietschnig and Martin Voracek included all available data pertaining to IQ increases from one generation to another: nearly 4 million test takers in 105 years. They found that IQ scores sometimes increased faster and sometimes more slowly. Check the difference between the 1920s and WWII in the figure above. Moreover, different aspects of intelligence change at different speeds. So-called crystallized intelligence (knowledge about facts) increased only at a rate of 0.2 points per year. So-called fluid intelligence (abstract problem solving), on the other hand, increased much faster at 0.4 points per year.

Five reasons for IQ growth

Five reasons appear to come together to explain this phenomenon:

1) better schooling: IQ growth is stronger in adults than in children, probably because adults stay longer and longer in school.

2) more experience with multiple choice tests: since the 1990s the multiple choice format has become common in schools and universities. Modern test takers are no longer put off by this way of asking questions in IQ tests and might resort to smart guessing.

3) less malnutrition: the slow IQ growth during the world wars might have something to do with a lack of nutrients and energy which the brain needs

4) better health care: the less sick you are, the more your brain can develop optimally

5) less lead poisoning: since the 1970s lead was phased out in paint and gasoline, removing an obstacle for healthy neural development

 Am I really smarter than my father?

According to the Flynn effect, my generation is 8 IQ-points smarter than that of my parents. But this only relates to performance on IQ tests. I somehow doubt that more practical, less abstract, areas show the same effect. Perhaps practical intelligence is just more difficult to measure. It is possible that we have not really become more intelligent thinkers but instead more abstract thinkers.

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Pietschnig J, & Voracek M (2015). One Century of Global IQ Gains: A Formal Meta-Analysis of the Flynn Effect (1909-2013). Perspectives on psychological science : a journal of the Association for Psychological Science, 10 (3), 282-306 PMID: 25987509

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Figure: self made, based on data in Figure 1 in Pietschnig & Voracek (2015, p. 285)

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How to increase children’s patience in 5 seconds

A single act increases adults’ compliance with researchers. The same act makes students more likely to volunteer to solve math problems in front of others. Moreover, it makes four-year-olds more patient. What sounds like a miracle cure to everyday problems is actually the oldest trick in the book: human touch.

How do researchers know this? Here is one experiment. In a recently published study (Leonard et al., 2014), four and five year old children were asked to wait for ten minutes in front of candy. The experimenter told them to wait before eating the candy because he had to finish paperwork. How long would children wait before calling the experimenter in because they wanted to eat the candy earlier? Four-year-olds waited for about six minutes while five-year-olds waited for about eight minutes. The task was similar to the classic Marshmallow test shown in the video.

 

The positive effect of touch

However, it all depends on whether the experimenter gave children a friendly touch on the back during the request to wait. If she did, four-year-olds waited for seven minutes (versus 5 minutes without touch) and five-year-olds waited for nine minutes (versus seven minutes without touch). A simple, five-second-long touch made four-year-olds behave as patiently as five-year-olds. It’s surprising how simple and fast the intervention is.

Touch across the ages

This result nicely fits into a wider literature on the benefits of a friendly touch. Already back in the eighties Patterson and colleagues (1986) found that adults spent more time helping with the tedious task of scoring personality tests if they were touched by the experimenter. Interestingly, the touch on the shoulder was hardly ever reported as noteworthy. In the early noughties Gueguen picked this effect up and moved it to the real world. He showed that touch also increases adults’ willingness to help by watching after a large dog (Gueguen & Fisher-Loku, 2002) as well as students’ willingness to volunteer to solve a math problem in front of a class (Gueguen, 2004).

The reason underlying these effects remains a bit mysterious. Does the touch on the back reduce the anxiety of being faced with a new, possibly difficult, task? Does it increase the rapport between experimenter and experimental participant? Does it make time fly by because being touched feels good? Well, time will tell.

Touch your child?

There are obvious sexual connotations related to touching people, unfortunately this includes touching children. As a result, some schools in the UK have adopted a ‘no touch’ policy: teachers are never allowed to touch children. Research shows that such an approach comes at a cost: children behave less patiently when they are not touched. Should society deny itself the benefits of people innocently touching each other?

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Guéguen N, & Fischer-Lokou J (2002). An evaluation of touch on a large request: a field setting. Psychological reports, 90 (1), 267-9 PMID: 11898995

Guéguen, N. (2004). Nonverbal Encouragement of Participation in a Course: the Effect of Touching Social Psychology of Education, 7 (1), 89-98 DOI: 10.1023/B:SPOE.0000010691.30834.14

Leonard JA, Berkowitz T, & Shusterman A (2014). The effect of friendly touch on delay-of-gratification in preschool children. Quarterly journal of experimental psychology (2006), 1-11 PMID: 24666195

Patterson, M., Powell, J., & Lenihan, M. (1986). Touch, compliance, and interpersonal affect Journal of Nonverbal Behavior, 10 (1), 41-50 DOI: 10.1007/BF00987204

ResearchBlogging.org

Music training boosts IQ

There are more and more brain training companies popping up which promise the same deal: improved intelligence. While there are doubts about their results, another sort of brain training has existed since the beginning of humanity: music. The evidence for its effectiveness is surprisingly strong.

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Music Lesson, 1936

Brain training in the 1930’s.

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Over the years, researchers have noticed that people who have taken music lessons are better on a wide range of seemingly unconnected tasks. Just look at this impressive list:

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Mathematics (across many different tasks; Vaughn, 2000)
Reading (understanding a written text; Corrigall & Trainor, 2011)
Simon task (quickly overcoming an easy, intuitive response in order to do a task right; Bialystok & DePape, 2009)
Digit Span (repeating a long list of random digits; Schellenberg, 2011)
Simple Reaction Time (pressing a button as soon as possible; Hughes & Franz, 2007)

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None of these tasks has anything to do with music classes. What is it that makes music lessons correlate with them? It could just be the socio-economic background: the more well-off or well-educated the parents the better the education of their children, including their music education (e.g., Corrigall et al., 2013). However, one can adjust for these differences with statistical tricks and the general picture is that the family background cannot fully explain the advantage musically trained children have on all sorts of tasks (e.g., Corrigall & Trainor, 2011; Schellenberg, 2011). If not family background, then what is underlying the music children advantage?

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Füssli: Liegende Nackte und Klavierspielerin

Brain training in the 18th century. I am referring to the left lady.

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Another contender is a common factor making some people good on all sorts of seemingly unrelated tasks and other people bad on nearly any task. This factor is called ‘g’ or general intelligence. An indeed, people who have enjoyed a musical education score higher on intelligence tests than people who did not. This has been shown across the globe: North America (Schellenberg, 2011), Europe (Roden et al., 2013), Asia (Ho et al., 2003†). The consistency across age groups is also impressive: 6-11 year olds (Schellenberg, 2006), 9-12 year olds (Schellenberg, 2011), 16-25 year-olds (Schellenberg, 2006). So, what holds these tasks and music education together is general intelligence. But that just opens up the next question: what causes this association between general intelligence and music lessons?
Music lessons cause higher intelligence
The most exciting possibility would be if music lessons actually caused higher intelligence. In order to make such a claim one needs to take a bunch of people and randomly assign them to either music lessons or some comparable activity. This random assignment ensures that any previous differences between music and non-music children will be equally distributed across groups. Random chance assignment at the beginning of the experiment ensures that any group differences at the end must be due to the whether children took music lessons during the experiment or not. Glenn Schellenberg did exactly this experiment with over 100 six-year-olds in Toronto (2004). Over a period of one year the children who learned to play the keyboard or to sing increased their IQ by 7 points. Children who were given drama lessons instead or simply no extra-curricular activity only increased by 4 points (likely because they started school in that year). A similar study which recently came out of Iran by Kaviani and colleagues (2013) replicates this finding. After only three months of group music lessons, the six-year-old music children increased their IQ by five points while children who were not assigned to music lessons only improved by one point. Across studies music lessons boost IQ.
It is worth reiterating how impressive this effect is. It has been found across three different music teaching approaches (standard keyboard lessons, Kodály voice lessons, Orff method). It has been replicated with two different sorts of intelligence tests (Wechsler and Stanford-Binet) as well as most of their subscales. It even came up despite the cultural differences between testing countries (Canada, Iran).
The take-home message couldn’t be any clearer. Music lessons are associated with intelligence not just because clever or well-off people take music lessons. A musical education itself makes you better across many tasks generally and on IQ tests specifically. No other ‘brain training’ has such a strong evidence base. Music is the best brain training we have.

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Eros and a youth

Ancient Greek brain training. I am referring to the gentleman on the right.

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Bialystok E, & Depape AM (2009). Musical expertise, bilingualism, and executive functioning. Journal of experimental psychology. Human perception and performance, 35 (2), 565-74 PMID: 19331508

Corrigall KA, Schellenberg EG, & Misura NM (2013). Music training, cognition, and personality. Frontiers in psychology, 4 PMID: 23641225

Corrigall, KA, & Trainor, LJ (2011). Associations Between Length of Music Training and Reading Skills in Children Music Perception: An Interdisciplinary Journal,, 29 (2), 147-155 DOI: 10.1525/mp.2011.29.2.147

Ho YC, Cheung MC, & Chan AS (2003). Music training improves verbal but not visual memory: cross-sectional and longitudinal explorations in children. Neuropsychology, 17 (3), 439-50 PMID: 12959510

Hughes CM, & Franz EA (2007). Experience-dependent effects in unimanual and bimanual reaction time tasks in musicians. Journal of motor behavior, 39 (1), 3-8 PMID: 17251166

Kaviani H, Mirbaha H, Pournaseh M, & Sagan O (2013). Can music lessons increase the performance of preschool children in IQ tests? Cognitive processing PMID: 23793255

Roden, I, Grube, D, Bongard, S, & Kreutz, G (2013). Does music training enhance working memory performance? Findings from a quasi-experimental longitudinal study Psychology of Music DOI: 10.1177/0305735612471239

Schellenberg EG (2004). Music lessons enhance IQ. Psychological science, 15 (8), 511-4 PMID: 15270994

Schellenberg, EG (2006). Long-Term Positive Associations Between Music Lessons and IQ Journal of Educational Psychology, 98 (2), 457-468 DOI: 10.1037/0022-0663.98.2.457

Schellenberg EG (2011). Examining the association between music lessons and intelligence. British journal of psychology, 102 (3), 283-302 PMID: 21751987

Vaughn, K (2000). Music and Mathematics: Modest Support for the Oft-Claimed Relationship Journal of Aesthetic Education,, 34 (3/4), 149-166 DOI: 10.2307/3333641

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Notes:

† Effect only marginally significant (0.05<p<0.1)

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images:

1) By Franklin D. Roosevelt Presidential Library and Museum [Public domain], via Wikimedia Commons

2) By Johann Heinrich Füssli: Liegende Nackte und Klavierspielerin, via Wikimedia Commons

3) attributed to the Penthesilea Painter, between circa 460 and circa 450 BC, via Wikimedia Commons
ResearchBlogging.org

The ironic effect of German PhD prestige

What would happen if a culture actually believed that a PhD does confer such a great set of transferable skills and is such an important test of character that the title is a career boost? A look at Germany gives an impression but it is not the science policy heaven one might expect.

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Schavan, Doktor, German science minister, doctor

By now she is just Schavan, ex-science minister.

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There can be no doubt that a PhD is associated with career boost in Germany. Just look at numbers like these: in 2005 in the US 6% of CEOs had a PhD, in France it was 4%. In Germany, however, the number was a full 59%. Note that this is not because more than half of the university graduates who leave German universities do so with a PhD in hand. Only 11% do. Actual pay mirrors this pattern. With merely a university diploma a female graduate gets nearly a third less pay than her PhD colleague.The message to ambitious people is clear: get that PhD no matter what career you want to pursue.
Moreover, having a German PhD is more than just a boost to one’s career. It is a boost to one’s entire social standing. Once the title is obtained it will cover one’s doorbell, one’s business card and even one’s passport. One will expect to be addressed with this title. In many respects it has become the modern equivalent of a title of nobility.
At first, this may sound like science policy heaven. There is a country where people who have earned scientific qualifications have got such a high social standing that they easily reach the highest ladders of society. The claims of transferable skills, test of character, training in critical thinking and analysis, … There is seemingly no need to convince Germans of these things, no need to do advertisements for science education, it appears. However, the opposite could be true. People who want to reach the highest ladders of society are clogging up the scientific training process. They have their career in mind, not scientific progress.
Merkel, zu Guttenberg

He was defense secretary and had a PhD. She is chancellor and has a PhD.

This leads to unintended consequences. A year ago, the German defense secretary (Dr) zu Guttenberg was about to lose his PhD title for plagiarism and consequently stepped down. Now, the German science minister (Prof. Dr) Schavan was forced to resign for the same reason. In between, a list of other German politicians was also found out. When prestige is more important than scientific value, the latter will obviously suffer. In this context the list of people with faulty PhDs at the highest levels of politics is hardly surprising.
What needs to change is a view that people with a PhD are somehow better people. At heart, a PhD is just a vocational qualification for science, a necessary step for pursuing a career in research or academia. It says nothing about the general quality of a person, or as Chris Chambers put it: ‘almost everyone who starts a PhD and sticks around long enough ends up getting one’. Of course you learn transferable skills while doing a PhD, but this does not mean that a PhD should be seen as a condition for having a business or politics career.
Paradoxically, everyone involved might actually benefit from less prestigious academic titles in the long run. Professors would be less bothered by PhD students who are not interested in research. The research literature would be less clogged up with easily obtained but uninteresting findings. And career minded graduates would not be required to spend years of their lives developing research skills which will perhaps not be needed in their later business or politics careers.
Now, how do you reduce the prestige of academic titles? There is no better way than to expose people in power who obtained them without actually deserving them. Thanks Dr zu Guttenberg and Prof. Dr Schavan.

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Figures:

1) via stabroeknews.com

2) By Bundeswehr-Fotos [CC-BY-2.0 (http://creativecommons.org/licenses/by/2.0)%5D, via Wikimedia Commons

Are some languages easier than others?

‘Long time no see’ is something I heard repeatedly in Britain even though it totally violates all the English grammar I learned at school. Clearly, Brits should correct this expression originating from Chinese Pidgin English rather than adopt it. The reason it entered common usage anyway is at the heart of why you might find English a lot easier to learn than the other British languages like Welsh or Gaelic. In a nutshell: when you learn English, it learns something from you as well.

Three years ago Gary Lupyan and Rick Dale published a (freely available) paper in which they looked at over 2,000 languages across the globe and quantified how difficult they are, e.g. by looking at their morphological complexity. Morphological complexity refers to how difficult it is to say a word in its correct form (‘went’ rather than ‘go-ed’). Its simpler counterpart is usually the use of more words to say the same thing (compare the sometimes irregular past like ‘gone’ with the always regular future ‘will go’). Using these principles Lupyan and Dale could show that languages which are spoken by more people tend to be simpler. Why?
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When languages grow big, they tend to get simple.
When languages grow big, they tend to get simple.
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Lupyan and Dale hypothesise that languages with more speakers also include more people who learned it when they were no longer children. As an adult, when you are not that good at learning a language anymore, you make yourself understood without speaking perfectly. Over time, these mistakes and simplifications are adopted by the language simply because difficult things never get learned by a new generation of learners. They are just forgotten. In some sense, the language learns what it can expect from its learners and what not. This drive towards simplification is a lot less strong when only expert language learners, i.e. children, are responsible for language transmission.
This year, a new study got published which directly looked at the proportion of adult second language learners in a given community rather than just assume it from the community size, as Lupyan and Dale did. Christian Bentz and Bodo Winter looked at case marking which is another pain to learn. In many languages around the world the Who does What to Whom pattern is not expressed through word order, like in English, but instead through case marking on words (similar to difference in roles marked by ‘he – him – his’). It turns out that on average languages which managed to retain a case system only have 16% of its speakers learn it after childhood, while the comparable number for no-case languages is 44%. Adults are bad at learning grammatical case systems, so it is forgotten if many adult learners speak the language.

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Melting Pot, English, Foreign Language, L2

His forebearers shaped English. As does he.

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So, yes, some languages are indeed easier. Learning them is a lot simpler. The reason being that language is not an invention of a single person. Instead, it is a communication tool shaped by the people using it. When Chinese people started using English they made many mistakes, some of them got adopted like ‘Long time no see’. Notice how it uses very little morphology, i.e. the words are all like you would find them in a dictionary, and no case at all (by that time English no longer had a full case system).
Follow the path of other adult language learners and you will meet with less resistance.
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Bentz C, & Winter B (2013). Languages with more second language learners tend to lose case Language Dynamics and Change, in press

Lupyan G, & Dale R (2010). Language structure is partly determined by social structure. PloS one, 5 (1) PMID: 20098492

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Figures:
1) adapted from Lupyan & Dale, 2010, p. 7
2) By Eneas De Troya from Mexico City, México (Melting Pot  Uploaded by russavia) [CC-BY-2.0 (http://creativecommons.org/licenses/by/2.0)%5D, via Wikimedia Commons

ResearchBlogging.org

delaying dementia without pills

‘What’s this? A potato?’ asked my friend’s grandfather during lunch. As always, he used his charming grin and characteristically loud voice. Even though the entire conversation was in Argentine Spanish – which I had learned only a short while before – I understood the oddity of the situation at once. Instead of a potato, the grandfather held a kiwifruit in his hands.
After only a short time of living with this family I noticed that the grandfather no longer had the mental abilities he once must have possessed in order to lead a successful business and raise an adorable family. He was undiagnosed but his behaviour reminded me of Mild Cognitive Impairment, which can progress to a more severe general cognitive impairment – Alzheimer’s Disease or more generally dementia – which usually cannot be cured. ‘What can be done?’ I was asked by my friend’s grandmother afraid of slowly losing the husband she had shared most of her life with. In broken Spanish I tried to explain to her what I would do: build up a cognitive reserve. This concept – related to the beneficial effects of, for example, high education or mentally demanding spare time activities – is perhaps the most promising strategy for delaying dementia.
A large scale analysis illustrates what a cognitive reserve can achieve. First of all, it can delay dementia. An Australian research team (Valenzuela & Sachdev, 2006) collected studies which recruited old people when they were still perfectly healthy and then tested them again after a few years to find out by how much their cognitive abilities had declined. The trend across more than 47,000 people was for higher education and more demanding leisure activities to slow down the creeping loss of mental abilities leading to dementia.

A German nun without experimental confounds.

The savvy reader may already notice a problem with this theory: high education is associated with a generally healthier lifestyle. Rather than cognitive reserve, we should perhaps simply be talking about healthy vs. non-healthy life styles. A Bavarian study ruled this problem out (Bickel & Kurz, 2009). They gained access to the education and dementia records of older female members of a religious order who lived as similarly as one can imagine. The 442 participants had shared a roof for more than five decades, shared meals together, had the same access to medical care. None smoked. None had any personal items. And still, 39% of sisters with low education suffered from dementia, compared to only 14% in the remaining group. Clearly, whether life style has an effect or not, the benefits of a cognitive reserve cannot be reduced to it. It delays dementia all by itself.
This beneficial effect of a cognitive reserve led me to give my advice. However, this strategy cannot stave off dementia forever or even slow it down once it kicks in. Nikolaos Scarmeas and colleagues from Columbia University (2006) found that more highly educated New Yorkers above 65 lose their memory faster around the time of an Alzheimer’s disease diagnosis compared to less educated city dwellers. Apparently, the benefits of a high education are absent around the time of diagnosis.
This raises the obvious question whether my advice was perhaps too late. Once on the road to Alzheimer’s there may be no turning back and efforts to delay the inevitable could make things worse. Given what we know about how the cognitive reserve actually works, I do not believe that this is true. First of all, a cognitive reserve is no cure against dementia but merely a way to delay it. The theory goes that brain pathology progresses whether you have a cognitive reserve or not. What a high education level and demanding leisure activities actually do is to avoid the usual outcome of brain pathology – e.g., easily noticeable memory problems of the kind I have described above. This is supported by studies which compared the brains of people with equal mental function in high age. Those with higher education have more amyloid deposits – a peptide associated with Alzheimer’s disease – as if they were able to deal with their reduced brain function in a better way (Kemppainen et al., 2008; Rentz et al., 2010). At some point though, the progressively worse brain function catches up with you and the resulting cognitive decline is faster.
Charles Hall and colleagues (2007; 2009) tested this overall model in the real world. His analyses of memory test scores of over 100 Bronx residents over the years shows the predicted trend. At first, a high cognitive reserve – whether education or leisure activities – delays the point in time when mental abilities suddenly decline rapidly. Each year in education delays this moment by two and a half months. Each day of mentally stimulating leisure activities delays it by two months. Once this moment is reached, though, the decline is faster with a higher cognitive reserve – as if the aforementioned brain pathology catches up. A cognitive reserve helps you to delay dementia but not to escape it.
cognitive decline; Alzheimer's disease; old age; dementia; cognitive reserve

The higher the education the shallower the decline before a break point, the later that break point, and the steeper the decline thereafter.

My friend’s grandfather had long been out of education. But the second source of a cognitive reserve – mentally demanding leisure activities – was not beyond him. What sort of activities work? A French research team led by Tasnime Akbaraly (2009) took a better look. They found that only a certain kind of leisure activity will delay dementia onset. Watching television and other passive behaviours won’t do. Neither do physical activities like going for a walk. Nor social ones like have friends or family over. The crucial set of activities are the mentally demanding ones: doing crosswords, playing cards, attending organisations, going to the cinema/theatre, practicing an artistic activity etc.
It is a mystery to me why this knowledge is not more widely spread. Dementia is one of the central challenges facing an ageing population as well as many old couples individually. Research shows that one does not need to be a passive spectator of mental decline. If a cognitive reserve has been built up, one can enjoy more years without showing signs of an incurable disease. That’s what I tried to say in broken Spanish to my friend’s grandmother: make him use his mind.

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Akbaraly, T., Portet, F., Fustinoni, S., Dartigues, J., Artero, S., Rouaud, O., Touchon, J., Ritchie, K., & Berr, C. (2009). Leisure activities and the risk of dementia in the elderly: Results from the Three-City Study Neurology, 73 (11), 854-861 DOI: 10.1212/WNL.0b013e3181b7849b

Bickel H, & Kurz A (2009). Education, occupation, and dementia: the Bavarian school sisters study. Dementia and geriatric cognitive disorders, 27 (6), 548-56 PMID: 19590201

Hall CB, Derby C, LeValley A, Katz MJ, Verghese J, & Lipton RB (2007). Education delays accelerated decline on a memory test in persons who develop dementia. Neurology, 69 (17), 1657-64 PMID: 17954781

Hall CB, Lipton RB, Sliwinski M, Katz MJ, Derby CA, & Verghese J (2009). Cognitive activities delay onset of memory decline in persons who develop dementia. Neurology, 73 (5), 356-61 PMID: 19652139

Kemppainen NM, Aalto S, Karrasch M, Någren K, Savisto N, Oikonen V, Viitanen M, Parkkola R, & Rinne JO (2008). Cognitive reserve hypothesis: Pittsburgh Compound B and fluorodeoxyglucose positron emission tomography in relation to education in mild Alzheimer’s disease. Annals of neurology, 63 (1), 112-8 PMID: 18023012

Rentz DM, Locascio JJ, Becker JA, Moran EK, Eng E, Buckner RL, Sperling RA, & Johnson KA (2010). Cognition, reserve, and amyloid deposition in normal aging. Annals of neurology, 67 (3), 353-64 PMID: 20373347

Scarmeas, N., Albert, S.M., Manly, J.J., & Stern, Y. (2005). Education and rates of cognitive decline in incident Alzheimer’s disease Journal of Neurology, Neurosurgery & Psychiatry, 77 (3), 308-316 DOI: 10.1136/jnnp.2005.072306

Valenzuela MJ, & Sachdev P (2006). Brain reserve and cognitive decline: a non-parametric systematic review. Psychological medicine, 36 (8), 1065-73 PMID: 16650343

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ResearchBlogging.org

Figures:

1) By André Karwath aka Aka (Own work) [CC-BY-SA-2.5 (http://creativecommons.org/licenses/by-sa/2.5)%5D, via Wikimedia Commons

2) By Doris Ulmann, 1882–1934. [Public domain], via Wikimedia Commons

3) Hall et al., 2007, p. 1661

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