We can make the world more intelligent by reducing poverty and violence, and improving nutrition and education, and we can use exercise, diet, and life-long learning to improve our own intelligence.
In this series:
Social Change for Cognitive Enhancement
Flynn Effect While there are powerful genetic constraints on our intellectual abilities we know that there are many environmental and behavioral factors that can encourage and discourage the development of intellectual abilities. For instance we know that people around the world have become more intelligent over the last century for entirely environmental reasons. In the 1980s, New Zealand political scientist James Flynn began to look at the questions used in intelligence tests in industrialized countries. The tests had changed, but the distribution of IQ hadn’t since an IQ of 100 is by definition the average intelligence for a given population.
But was today’s 100 the same as last year’s? Flynn found that IQ tests have been getting harder, and that intelligence has been rising by about three points per decade. People who would have been in the top 10th percentile of intelligence a hundred years ago would today be among the 5% least intelligent people in the population. Compared to the previous generation, the number of people who score high enough to be classified as a "genius" has increased more than 20 times. The “Flynn effect” has now been documented in dozens of countries, and it is beginning to be observed in the developing world.
There is no widely accepted explanation for the Flynn effect, but the causes are entirely environmental. Improved nutrition has contributed since there is a well documented link between malnutrition and lower intelligence. The decline in violence has reduced the stressors on children’s cognitive development. The percent of the population that can read has increased rapidly around the world, as has earlier, better and more widespread mandatory education. As family sizes shrank each child received more attention. As people moved from slow, culturally isolated farms to fast, complex cities their brains were stimulated. Especially stimulating was greater exposure to all kinds of media, including books, magazines, radio, television and the Internet. While none of these factors appears to explain the Flynn effect by itself, each appears to contribute something.
Poverty Reduction So a global effort at intelligence enhancement would start with the obvious social policy targets of reducing poverty, illiteracy, malnutrition, disease, violence and inequality, all of which impair cognitive abilities. Improvments in women’s education has a double benefit since it also reduces family size, improving the attention and resources children get and the quality of their care. Even when inequality does not reduce material resources or access to education, it introduces stressors such as “stereotype threat” that impair the cognitive ability and test performance of the poor, women and ethnic minorities.
Improvements in cognition in return tend to support the rule of law, economic growth, democratic and accountable institutions, and support for policies that reduce inequality. In one study the average level of a nation’s cognitive ability was correlated with GDP and economic growth, the rule of law, more economic equality, smaller families, lower rates of murder and higher rates of solved murders.
Increasing Literacy and Improving Pedagogical Methods There is some evidence that quality and length of education improves at least crystallized intelligence, if not fluid intelligence. Early childhood education from prekindergarten through first grade, has an effect on cognition and academic achievement through the college years. But information technology and artificial intelligence now allow us to move beyond the industrial model of education that developed a century ago to more personalized and adaptive curricula, and life-long learning tools, that will hopefully identify and develop our fullest natural capacities throughout the life course.
Brain-Healthy Lifestyle and Practices
Belief in Neuroplasticity Unfortunately reading the previous essay on the genetic constraints on intelligence may have just impaired your intelligence. Research shows that groups that are told they can improve their cognitive performance improve their performance more than groups who are told that cognitive performance is largely genetic. So we need to remind ourselves that there are a lot of lifestyle changes that we can make to improve our intelligence. In a paper titled “Towards a Smart Population: A Public Health Framework for Cognitive Enhancement” Lucke and Partridge argue that the first and most impactful ways to enhance cognition are improvements in sleep, exercise, diet and reducing stress.
Sleep As a result of spread of electricity and the distractions of modern life many of us do not get adequate sleep, and lack of sleep has an immediate impact on reaction time, working memory and other intellectual abilities. We need at least six hours of sleep to consolidate learning from the previous day, and short naps before tests improve performance.
Exercise Similarly, as we migrated from the savannah to the farm to the factory and finally to our mostly sedentary modern lives, we get much less exercise than we need for physical and cognitive health. Physical exercise improves cognition by improving cardiovascular health and boosting the amount of neural growth factor in the brain (brain-derived neurotrophic factor or BDNF)   Exercise programs have been shown to improve performance on cognitive tests for both young and old.   Twenty to thirty minutes of aerobic exercise improves self-regulation and performance in reading and math for children with ADHD.  
Brain Foods As to diet there is plenty of evidence that some things we eat can harm intelligence, but the evidence for actual brain foods is still thin. Environmental toxins from lead to pesticides have been found to have a widespread effect on impairing intelligence. Obesity is correlated with low intelligence, but that appears to be mostly because those with more self-control and intelligence are less likely to get fat , so that weight loss has little impact on cognitive ability. The jury is also still out on whether calorie restriction or short-term fasting are good for cognition.
The evidence is good that a Mediterranean diet rich in plants, olive oil, yogurt and fish, slows cognitive decline in old age and reduces the risk of dementia.  Unfortunately, while there is good evidence that omega-3s from fish and other foods are good for cognition, we still don’t understand which other aspects of the Mediteranean diet provide cognitive benefits. It doesn’t seem to be the antioxidant content of the diet for instance. Foods high in antioxidants and antioxidant supplements do nothing for cognition.    
Activities that Build Cognitive Reserve One idea that has gained support is that a lifetime of intellectual engagement strengthens our neural architecture and builds a “cognitive reserve” that slows cognitive decline in old age. The amount of education you acquire reduces your lifetime risk of developing dementia, and slows its progression. People who read a lot, stay engaged in recreational activities, learn a musical instrument, or learn more than one language perform better on cognition tests throughout their life, and develop dementia more slowly.    Teaching is especially beneficial; learning something with the expectation that you will be teaching others improves memory of the material.
Socializing The benefits from socializing appear to complement the benefits of solitary cognitively demanding activites. In one experiment seniors were taught either digital photography or quilting, or both, and practiced these hobbies for three months, while control groups either socialized or practiced less cognitively demanding hobbies by themselves. After three months all five groups had seen some improvements in working memory, with the biggest gains in the digital photography group. But surprisingly the group that just socialized had improved in speed of thought and “mental control” more than the photography or quilting groups.
Mindfulness Meditation In a previous essay we reviewed the evidence for benefits to executive function from meditation, and those functions are also important to intelligence and cognition in general. One of the features of high IQ is the ability to focus on important information and ignore irrelevant information, and mindfulness meditation helps train this ability. Mindfulness meditation improves memory capacity and performance on tests,  and introduces more thoughtful deliberation into decision-making, reducing the influence of cognitive biases.    I’ll talk more about the importance of learning to recognize one’s own cognitive biases in the next essay on fairness.
Multitasking and Brain Games I am a chronic multitasker, which is embarassing since the research shows that for most of us multi-tasking and digital distraction significantly impair attention, memory and performance. Multitasking is a form of attention deficit disorder, motivated by the brain’s search for dopamine hits, Of course I assume that I am among the few who can successfully multitask, but the research also shows that people who think they do it well are generally performing significantly worse. In the last year I have at least learned to only have my email open five minutes per hour.
Help for multitaskers may be on the way however. About five percent of people are capable of multitasking, people with superior executive control and working memory. With targeted brain games and neurofeedback these cognitive skills can be trained. A lot of games and puzzles – sudoku, crosswords, scrabble - only train your brain to do that particular task better, and even then the improvements don’t last long. But some forms of brain training are being found to have persistent benefits across a number of cognitive abilities.
For instance n-back is a challenging memory training game that was invented in the 1950s. It presents you with a series of letters, numbers, colors and sounds, and asks you to remember them well enough to match them several steps ahead. It exercises many parts of the brain and recent meta-analyses of twenty three studies found that it had a small positive effect on improving working memory and fluid intelligence. Other programs are looking at targeting the games at improving core cognitive abilities, or combining physical exercise with brain training games and environmental enrichment which also seems to have a promising impact on improving general cognitive functions.
The Exocortex and Collective Intelligence Whether games turn out to be a powerful way to broadly improve intellectual abilities it is clear that we are all now orders of magnitude smarter as a consequence of information technology. We carry around devices that allow us to store more information than anyone could possibly remember, and to access the rapidly growing body of human knowledge with a few clicks. The mining of consumer behavior data by firms like Netflix, Amazon and Facebook allow to discover films, books and news that we otherwise would never have seen. Wearable interfaces like Google Glass, and virtual assistants like Google Now and Siri, will become increasingly miniaturized, inconspicuous and contextually helpful, giving us information we may not even know that we need. A large amount of effort is being put into online and computerized forms of education, validated with concrete learning outcomes, that will undoubtedly clarify which types of exercises do improve real-world decision-making skills. These will all start as part of our wearable exocortical assistants and ubiquitous computing environment, then be integrated with “augmented cognition” devices that finetune our attentiveness and learning, and then be integrated into the brain-machine interfaces to come.
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