Today, we’re gonna talk about the content we consume and what that consumption is doing to our minds.

But before I started to talk about content I wanna talk about something else we consume.

I wanna talk about food.

When we consume food, we experience its taste and we benefit from its nutritional value.

Taste is subjective. For person to person it can vary.

Nutrition is universal and objective.

Those of us don’t like our broccoli might say that food and taste and nutrition don’t go well together.

Others, strange people, like healthy food.

At minimum we can agree that food can be tasty without being nutritious and vice versa.

Now one time the American diet consisted primarily of nutritious food such as organic vegetables, whole grain, grass-fed beef.

But as food production became market-driven, food companies found that making food tastier is cheaper than making food nutritious, that consumers actually prefer tastier food rather than healthier food.

Overtime, nutritious food was supplanted by inexpensive cheap food that was available to everybody didn’t have a lot of nutrition, while healthy nutritious food was limited to the dietary elite, the people that shop at Whole Foods.

The gradual erosion of the nutritional value of our food was ignored by almost everybody until the obesity epidemic transformed our love handles into passion Bannisters.

And now we’re the fattest country in the developed world.

I believe when we consume content it’s a lot like eating food.

Like food, content has a taste to it.

When you experiencce The Avengers, it tastes differently than The Dark Knight.

Which you prefer is just a matter of taste.

Never before has the content menu offered so many varied excellent tastes.

If you enjoy consuming content, the world is an amazing place.

But content also has a nutritional value.

Just as food feeds our bodies, content feeds our minds.

And as with food, the nutritional effective content is objective and universal.

I’ve summarized the findings from over 40 studies on how content consumption affects us.

Nutritious contents increase our knowledge. It expanse our vocabularies. It improves reflection, critical thinking, problem-solving, visual acuity, imagination.

Unhealthy content shortens our attention span. It damages our concentration. It weakens our problem-solving skills and increase impulsivity. And like simple sugars, it leaves you addicted and wanting more.

We already know that the American diet of food rapidly changed in the 20th century in a way that made it tasty but less nutritious.

The American mind has also changed rapidly.

Did these changes leave our mental diet a healthy balanced on? Or have we began to feed our minds as badly as we feed our bodies, consuming nothing but junk all day?

If our mental menu is nutritious, we should see people get smarter and sharper. If our mental menu is unwholesome, we should expect to see a spreading epidemic of stupidity that would parallel the epidemic of obesity.

Let’s start by examining our reading habits.

Reading, it turns out it’s the most nutritious way you can consume content.

The better you are at reading, the better you are at thinking.

And how do you get better at reading? By reading.

Educators call this principle the Matthew effect.

In a series of studies, researchers Cunningham and Standage have demonstrated repeatedly that a high volume of reading increases knowledge, broadens vocabulary and reduces the cognitive decline of aging.

And all of these studies were controlled for general intelligence and verbal abilities.

So in other words, it’s not that smart people reading although they do, but that reading makes you smarter.

No other type of content consumption has been shown to provide these benefits.

When you wanna strengthen your muscles, the best way to do it is to lift heavy weights, so I’ve been told.

When you wanna strengthen your mind, the best way to do it is to read challenging literature.

So how challenging is our literature today compared to the past?

I explored a corpus of best-selling books for the 300 years period from 1710 to 2010 and assessed sentence length, paragraph length and reading grade.

Sentence length has been steadily declining for decades from an average of 40 words per sentence to an average of 14.

It’s now as abrupt as our spoken speech. It can’t decrease much further unless we start speaking in tweets.

Paragraph length held steady from the beginning of the 18th century until the middle of the 20th century when it suddenly began to plummet at an accelerating rate. This is when the era of TV began.

Books written before 1950 had an average paragraph length of over a hundred words. Books written after 1950 had an average paragraph length of 71 words.

And if you look at just books written after 2000, the average paragraph has dropped to 58 words.

Consequently the reading grade of best-selling books has also plummeted dramatically over time.

The reading grade started at 14.5 for bestsellers in the 1700s and then declined inexorably. By 2010 it was down to grade 4.5.

Now remember. This has nothing to do with taste. The data is not talking about the aesthetic taste of consuming book. There are enjoyable books written at every reading grade at every genre.

When we consider reading grade we’re only talking about nutritional value. And from that point of view, what we’ve seen is that bestsellers were once books that challenged the college-educated mind and they are now books that are easy for 5th graders.

Also note that the reading grade of the works clusters tightly as we get around 1940. And the 1940s is when researchers began to develop and promote what they termed readability scores.

A readability score is a measure of the degree to which material can be understood by readers. So this Flesch-Kincaid reading grade is a readability score.

Once publishers were able to measure readability, they could target the works they published at whatever reading level would reach the greatest number of people.

At the time when the average American could read at the 8th grade level but enjoyed reading at the 6th grade level, that is for recreation. People liked to read texts that are two grades beneath their actual reading level.

Unfortunately, research by Professor Lev Vygotsky found that reading is most nutritious when it’s slightly above your current reading level. Reading books that are at your present level or below does not improve comprehension.

If you wanna increase your vocabulary and knowledge you have to encounter new words and new facts.

And this is unfortunate because it means there’s a negative correlation between taste and nutrition.

The books you enjoy are not gonna be the books that are best for you.

So as publishers started to use the readability scores to guide their publishing it was inevitable they were going to start making the material tastier but less nutritious because that’s what we the consumers wanted.

And this is similar to what happened when farmers substituted corn for grass in the livestock. The beef tasted better but it became less nutritious.

The publishers of newspapers and magazines hired readability consultants to purposefully simplify their written content. And as a result, in the past 60 years, the reading level of newspapers and magazines has dropped by 2 to 4 grades.

Decreasing the reading grade of the works allow the newspaper-magazine publishers to greatly increase the audience but it also reduced the nutritional value of reading.

Now it’s not surprising that market forces are going to cater towards taste rather than nutrition.

What’s especially troubling is that our textbooks have also been dumbed down.

The average 8th grader is now reading from the textbooks at the 5th grade reading level.

The literature text that was required of 12th graders is nowadays simpler than the average 8th grade reading book before World War II.

Despite the fact that books are easier to read than ever, the average American today reads less than ever.

60% of 18 to 24 year olds used to read literature in 1982. By 2002, this had dropped to 43%.

The percentage of adults who read for pleasure is decreasing by 7 percent every year.

And the average annual spending has dropped from 33 dollars to 28 dollars in the last 20 years.

It’s accepted that the declining popularity of written media has been caused by the rise of screen media.

So it’s a dietary shift. It means that not only are Americans reading simpler books, flipping through simpler magazines and learning from simpler textbooks, they’re doing less all of the above.

And these changes have occurred simultaneously with measurable decreases in our nation’s verbal skills.

This is what the mean verbal SAT scores look like after you correct for the fact that the test makers have been adjusting the scores upward to hide the decline.

There was a 50 point drop between 1962 and 1979. And 1962 TV reached 90% market penetration and textbooks got simplified.

There has been another 10-point drop since 2000 when Internet access went mainstream.

Here’s a comparison of the reading ability of adults in 1949 and 2003, the world before TV and after TV.

The number of US adults capable of reading at the 10th grade level dropped from 54% to 20%.

The number of reading at even the 6th level dropped from 83% to 52%.

In other words, more Americans could read at the 10th grade in 1949 than can even read at the 6th grade level today.

And this is despite the fact that in 1949 the average American had 8 and a half years of education and now the average adult has 12 and a half years of education.

So 4 and a half extra years of education to do worse.

So far I focused on printed material because it’s the leafy green vegetables of the content diet.

What about screen media? How are they doing?

Well, printed media has obviously declined in popularity. Screen media is doing a little more better.

Watching television is now the developed world’s favorite activity taking up more free time than anything else.

The only thing we do more than watching TV is sleep.

American aged 15 to 24 spend 2 hours a day watching TV and seven minutes reading for pleasure.

If books are the leafy green vegetables in the diet, TVs and computers are the daily bread.

Now, the good news is that screen media has been shown to increase visual spatial intelligence.

Video games have also been shown to improve hand-eye coordination, thank you, 5-year-old who beat me on xbox, and divided attention which makes us better at tracking multiple objects at once.

The Internet has been shown to increase transactive memory which is sort of a meta memory of where to find information like I no longer remember my birthday so I google it.

In particular, the increase in visual spatial intelligence has been profound and you can see the increased scores on the Raven progressive matrices.

These are non-verbal IQ tests which provide a measure of visual intelligence. And screen media are like vitamins for visual ability. Tasty tasty vitamins.

The bad news is that all types of screen media come at a substantial cost.

Professor Patricia Greenfield summarizes the findings as damages to our deep cognitive processes.

A study by the American Academy of Pediatrics found that for every hour a child spent watching television there was a 9% increase in their attention problems.

Children between age 11 and 15 spent 53 hours a week in front of the screen.

A 2005 study published in Brain and Cognition has found that the more we watch television during our middle years, aged 20 to 60, the greater our risk of Alzheimer’s.

A 2006 study in Southern Medical Journal found that watching lots of soap operas and talk shows was associated with clinically significant impairment of attention, memory and psychomotor speed in older people like your professors.

A large part of television effect on our mind is caused by what Pavlov calls the orienting response. This is the instinctive response we get to sensitivity of change, vision, sound.

Our brains get turned on by stimuli which triggers dopamine release whenever are....

Sorry.

In the last 2 decades, researchers have begun to examine how the shots-cuts edits and effects of television activate the orienting response.

A study of EEG activity in the processing of television published in Communications Research found that the more you have the shots quickly edited the more effect television has on your nervous system.

So the average length of shots in our screen media is a benchmark for how healthy it is. To watch shorter cuts make the content more arousing, more addictive and more damaging to our attention span.

And unfortunately that’s the direction the screen media’s moved in.

In 1972, the average shot length of a US film was 8.6 seconds. Now it’s down to 2.5 seconds.

Film makers call this MTV editing because everything looks like a music video now.

Children’s shows are particularly fast cut. A longitudinal study of Sesame Street found that the average shot length have, over the last 26 years, even dumbed down Sesame Street.

These trends are a function of the decreased attention span of the modern mind as well as contributing factors to its further reduction.

Attention deficient viewers seek out shorter hyperkinetic content which in turn leads to their minds becoming even more attention deficient.

This is a vicious cycle that becomes a chiche.

How many of you found the blockbuster from the old days to be too slow-paced, boring and long?

In fact, even 18 minutes is probably too long for a talk in today’s attention deficient world. So we’re gonna have a halftime show.

You have to imagine this music playing during this part of the presentation because when we listen to music it triggers a complex neural process.

A controversial 1993 study published in Nature found that listening to Mozart increases your spatial task performance.

Follow-on studies have found similar effects from other music with similarly complex structure such as Bach, Yanni.

A 2011 study found that cognitive recall was increased when listening to unfamiliar classical music.

A 2012 study found that listening to classical music could improve performance of stressful tasks like TED Talks by calming the sympathetic nervous system.

Loud fast music induces stress on the sympathetic nervous system.

So these findings are correct.

And these are less clear.

The most nutritious music would be sedating, complex and unfamiliar, while the least nutritious music would be loud, simplistic and sound familiar.

So what direction is pop music been heading in the last 50 years?

Well, analysts at the Spanish National Research Council actually evaluated 465,000 pop songs from 1955 to 2010 to evaluate loudness, harmonic, complexity and timbrel diversity.

Since 1950s, music has tended towards increased inherent loudness. There’s been a reduction in the diversity of chords but given song a reduction in the number of musical pathways between each chord and the timbers of different instruments has gotten more homogeneous every year.

Since 1955, pop music uses fewer and fewer tones from the available palette.

So overall in the last 50 years, pop music has become louder, more simplistic and more similar.

It’s probably becoming less nutritious.

And this again is not a measure of taste. In fact we should probably not even discuss my taste in music or my jazz album.

Let’s just say that from an objective review of the cognitive benefits of music you are much better off with Mozart.

So we have answered our starting question.

Just as the nutritional value of food decline from healthy to unhealthy, so too has the nutritional value of our content decline dramatically.

Instead of a balanced diet that mixes great tasting content with nutritious fare, we instead feed our minds with the equivalent of deep fried doughnuts.

If we care, of course I did, bad few.

If we care of our mind as much as we care about the health of our bodies, we need to begin to balance our content diet as urgently as we need to balance our food diet.

We don’t need to give up video games. We don’t need to quit watching CSI. We can even keep listening to Beyonce.

But it wouldn’t hurt us to read something really hard like Edward Gibbon’s Decline and Fall of the Roman Empire reading grade 17.4 or to watch something slow and methodical like The Godfather.

Or you can listen to something sonorous and melodic like Mozart.

Just don’t do all 3 at once because multitasking is the information superhighway to hell.