Category: Intelligence

Genetic study finds that, beyond looks, this is the most important quality in a potential partner.

People are more likely to marry those with a similar level of intelligence to themselves, research finds.

It shows that when looking for a partner, people generally want someone similar to themselves.

Intelligence, like many other traits, is partly controlled by our genetic makeup.

So, effectively, people tend to pick others who have similar genetic traits.

The study’s authors write:

“Humans generally do not choose their mates randomly.

In search for a suitable mate, among the highest-ranking qualities people look for in a potential partner are intelligence and educational attainment.”

And when you look at any random couple, there is a surprisingly high correlation between the two different people’s intelligence and their education.

The conclusions come from a UK DNA study of 1,600 married or cohabiting couples.

Dr David Hugh-Jones, the study’s first author, said:

 “Our findings show strong evidence for the presence of genetic assortative mating for education in the UK.

The consequences of assortative mating on education and cognitive abilities are relevant for society, and for the genetic make-up and therefore the evolutionary development of subsequent generations.”

Dr Hugh-Jones pointed out that over time the forces of evolution can increase social inequality:

“Assortative mating on inheritable traits that are indicative of socio-economic status, such as educational achievement, increases the genetic variance of characteristics in the population.

This may increase social inequality, for example with respect to education or income.

When growing social inequality is, partly, driven by a growing biological inequality, inequalities in society may be harder to overcome and the effects of assortative mating may accumulate with each generation.”

In other words, if intelligent people continue to marry other intelligent people, then the genes for intelligence continue to be concentrated in a small group.

The study was published in the journal Intelligence (Hugh-Jones et al., 2016).

The parental behaviour that lowers children’s IQ.

Children who were spanked in childhood have lower IQs, a study finds.

The more children were spanked, the lower their IQ, the research also found.

The probable reason is that spanking is highly stressful for children.

It can leave them with post-traumatic stress disorder.

An ongoing fear of terrible things happening — being easily startled — is linked to a lower IQ.

Parents who continue to use corporal punishment into the teenage years may hamper their children’s brain development even more.

Professor Murray Straus, the study’s first author, said:

“All parents want smart children.

This research shows that avoiding spanking and correcting misbehavior in other ways can help that happen.

The results of this research have major implications for the well being of children across the globe.

It is time for psychologists to recognize the need to help parents end the use of corporal punishment and incorporate that objective into their teaching and clinical practice.

It also is time for the United States to begin making the advantages of not spanking a public health and child welfare focus, and eventually enact federal no-spanking legislation.”

The results come from research that followed 704 children from the ages of 2 – 4 until they were 5 – 9 years-old.

The IQ of children who were not spanked between 2 and 4-years-old was 5 points higher when tested four years later than those who were spanked.

Professor Straus said:

“How often parents spanked made a difference.

The more spanking the, the slower the development of the child’s mental ability.

But even small amounts of spanking made a difference.”

The psychologists also found that countries in which spanking children was more common saw stronger links between corporal punishment and IQ.

Professor Straus said:

“The worldwide trend away from corporal punishment is most clearly reflected in the 24 nations that legally banned corporal punishment by 2009.

Both the European Union and the United Nations have called on all member nations to prohibit corporal punishment by parents.

Some of the 24 nations that prohibit corporal punishment by parents have made vigorous efforts to inform the public and assist parents in managing their children. In others little has been done to implement the prohibition.”

The study was published in the Journal of Aggression Maltreatment & Trauma (Straus & Paschall, 2009).

Amazingly, it also makes women appear more faithful.

More revealing clothing can actually make women appear more intelligent and more faithful, new research finds.

The study conflicts with previous research finding dressing sexy has the opposite effect.

The research may demonstrate changing stereotypes about women.

The study’s author, said:

“Contrary to our predictions it was the sexualised clothing which resulted in higher intelligence and faithfulness ratings.”

For the research, 64 people were shown pictures of a fashion model dressed in two different ways.

In one picture she had on a very short skirt, a low-cut top and a jacket.

In the second picture the skirt was longer and the top covered more flesh.

Study participants ranked the woman for intelligence, personality, faithfulness, perceived job status, morality and intention to have sex.

There was no difference in the ratings between the two styles of dress except for intelligence.

Dr Alfredo Gaitan, the study’s first author, said:

“Have attitudes changed so much that people are not making negative judgments based on a woman’s dress?

We think there are still negative attitudes out there, but perhaps people are seeing the sexy look more positively.”

The study was presented at the British Psychological Society’s conference in Nottingham (Gaitan & Worrell, 2016).

The effects of this parental behaviour were still detectable when the offspring were 42-years-old.

Children that spend more time with their fathers have a higher IQ, a new study finds.

The results come from research that followed 11,000 British men and women for over thirty years.

Parents were asked how much time the father spent with their children:

• Reading with them.
• Organising outings.
• General ‘quality time’.

Thirty years later, children whose fathers had spent more time with them had better jobs and higher IQs.

The higher IQs and improved social mobility were still detectable when the offspring were 42-years-old.

Dr Daniel Nettle, who led the research, said:

“What was surprising about this research was the real sizeable difference in the progress of children who benefited from paternal interest and how thirty years later, people whose dads were involved are more upwardly mobile.

The data suggest that having a second adult involved during childhood produces benefits in terms of skills and abilities that endure throughout adult life.”

The researchers also found that fathers tended to pay more attention to their sons than their daughters.

The study was published in the Journal of Evolution and Human Behaviour (Nettle et al., 2016).

Parent image from Shutterstock

What it says about a person who posts wise-sounding but meaningless quotes to social media.

People who are impressed by wise-sounding-but-meaningless quotes tend to have a lower IQ.

The conclusions come from a new study which asked people to evaluate a series of statements.

Some of the statements were mundane like: “most people enjoy some kind of music”.

Others were from Deepak Chopra, a well-known author and public speaker.

These included quotes like:

“Attention and intention are the mechanics of Manifestation.”

Imagination is inside exponential space time events.

Nature is a self-regulating ecosystem of awareness.

In the midst of movement and chaos, keep stillness inside of you.”

The quotes seem primarily designed to impress you rather than actually inform you of anything.

Other quotes were randomly generated by a website that mixes up buzzwords into grammatically correct but meaningless sentences.

These were compared with statements which are considered profound(-ish), but are written in plain English, such as:

“A river cuts through a rock, not because of its power, but its persistence.”

Worryingly, some people failed to notice the difference between the meaningless quotes and the genuinely profound ones.

More hearteningly, on average, the genuinely profound statements were given the highest ratings.

Mr Gordon Pennycook, a PhD student who led the research, writes:

“Our results support the idea that some people are more receptive to this type of bulls**t and that detecting it is not merely a matter of indiscriminate skepticism but rather a discernment of deceptive vagueness in otherwise impressive sounding claims.

Those more receptive to bulls**t are less reflective, lower in cognitive ability – numeracy, verbal and fluid intelligence), are more prone to ontological confusions and conspiratorial ideation, are more likely to hold religious and paranormal beliefs, and are more likely to endorse complementary and alternative medicine.”

They continue:

“Chopra has over 2.5 million followers on “Twitter” and has written more than twenty New York Times bestsellers.

Bull***t is not only common; it is popular.

Chopra is, of course, just one example among many.

Using vagueness or ambiguity to mask a lack of meaningfulness is surely common in political rhetoric, marketing, and even academia.

[…]

“One of the most salient features of our culture is that there is so much bull***t.

Everyone knows this.

Each of us contributes his share.””

The study was published in the journal Judgment and Decision Making (Pennycook et al., 2015).

Life begins image from Shutterstock

Scans of over 8,000 people were analysed by scientists searching for a link between IQ and brain size.

For 150 years scientists have suspected that a bigger brain means a higher IQ.

But the link may be much smaller than previously thought.

Now, a new study finds that having a larger brain only has a very small link to a higher IQ.

The results of brain scans from over 8,000 people were analysed by scientists at the University of Vienna and elsewhere.

Dr Jakob Pietschnig, who led the study, said:

“The presently observed association means that brain volume plays only a minor role in explaining IQ test performance in humans.

Although a certain association is observable, brain volume appears to be of only little practical relevance.

Rather, brain structure and integrity appear to be more important as a biological foundation of IQ, whilst brain size works as one of many compensatory mechanisms of cognitive functions.”

So, what makes the human brain superior is the connections not its size — relative or otherwise.

This is why, although women have smaller brains than men (on average), there is no difference in IQ between men and women (on average).

The study was published in the journal Neuroscience and Biobehavioral Reviews (Pietschnig et al., 2015).

Network brain image from Shutterstock

Are eldest children more intelligent with ‘better’ personalities? Massive study settles this sibling rivalry.

Eldest siblings are more intelligent, a new study of 377,000 high school students finds.

However, the difference is equal to, on average, just one IQ point.

This difference is so small as to be almost meaningless.

There were also consistent differences in personality.

Eldest siblings tended to be more outgoing, conscientious and agreeable, while being less anxious.

But, again, these differences were very small.

Professor Brent Roberts, who led the study, explained how small the differences were:

“In some cases, if a drug saves 10 out of 10,000 lives, for example, small effects can be profound.

But in terms of personality traits and how you rate them, a 0.02 correlation doesn’t get you anything of note.

You are not going to be able to see it with the naked eye.

You’re not going to be able to sit two people down next to each other and see the differences between them.

It’s not noticeable by anybody.”

The study controlled for factors like economic status and the number of children.

Professor Rodica Damian, who co-authored the study, said:

“The message of this study is that birth order probably should not influence your parenting, because it’s not meaningfully related to your kid’s personality or IQ,”

The research was published in the Journal of Research in Personality (Damian & Roberts, 2015).

Siblings image from Shutterstock

Breastfeeding benefits likely result from long-chain saturated fatty acids in mother’s milk.

More infant breastfeeding is linked to higher intelligence, a longer period in education and greater earnings 30 years later, a new study finds.

Dr Bernardo Lessa Horta, who led the study, said:

“The effect of breastfeeding on brain development and child intelligence is well established, but whether these effects persist into adulthood is less clear.

Our study provides the first evidence that prolonged breastfeeding not only increases intelligence until at least the age of 30 years but also has an impact both at an individual and societal level by improving educational attainment and earning ability.

What is unique about this study is the fact that, in the population we studied, breastfeeding was not more common among highly educated, high-income women, but was evenly distributed by social class.

Previous studies from developed countries have been criticized for failing to disentangle the effect of breastfeeding from that of socioeconomic advantage, but our work addresses this issue for the first time.”

Breastfeeding benefits

The study of breastfeeding benefits followed almost 6,000 infants in Brazil from 1982.

They were placed into one of five groups depending on how often they were breastfed.

At the same time the researchers controlled for other factors that might affect IQ, like family income, maternal smoking and genetics.

The researchers found that infants who were breastfed for a year scored, on average, 4 IQ points higher than those who were breastfed for less than a month.

Breastfed infants also went on to spend one more year in education, on average, and earn one-third of the average national income more.

Dr Horta said:

“The likely mechanism underlying the beneficial effects of breast milk on intelligence is the presence of long-chain saturated fatty acids (DHAs) found in breast milk, which are essential for brain development.

Our finding that predominant breastfeeding is positively related to IQ in adulthood also suggests that the amount of milk consumed plays a role.”

The study is published in the journal The Lancet Global Health (Victora et al., 2015)

Breastfeeding image from Shutterstock

Chemicals that may cause a drop in children’s IQ are in products all around our houses.

Children exposed prenatally to high levels of phthalates — commonly used in plastics and scented products — have IQ levels seven points lower than those exposed to low levels, a new study finds.

The study is the first to find a connection between phthalate exposure during pregnancy and reduced IQ in children.

The 328 women and their children in the study were from low-income communities in New York City.

Researchers at Columbia University’s Mailman School of Public Health measured levels of four common phthalates, including di-n-butyl phthalate (DnBP) and di-isobutyl phthalate (DiBP), during pregnancy (Factor-Litvak et al., 2014).

The children were given an IQ test at 7-years-old.

The results, published in the journal PLoS ONE, showed that children who were in the top 25% for exposure to two particular phthalates (DnBP and DiBP) had IQs around 7 points lower than those who were in the bottom 25% for exposure.

Professor Robin Whyatt, one of the study’s senior authors, said:

“The magnitude of these IQ differences is troubling.

A six- or seven-point decline in IQ may have substantial consequences for academic achievement and occupational potential.”

The researchers controlled statistically for other factors that influence children’s IQ, such as maternal IQ and education as well as the home environment.

Avoiding phthalates

While it is impossible to avoid phthalates completely, they are found in these common products, amongst others:

• Hairspray.
• Plastic containers used for microwaving food.
• Lipstick.
• Air fresheners.
• Dryer sheets.
• Nail polish.
• Some soaps.
• Recycled plastics labelled 3,6 or 7.

Dr. Pam Factor-Litvak, who led the study, said:

“Pregnant women across the United States are exposed to phthalates almost daily, many at levels similar to those that we found were associated with substantial reductions in the IQ of children.

While there has been some regulation to ban phthalates from toys of young children, there is no legislation governing exposure during pregnancy, which is likely the most sensitive period for brain development.

Indeed, phthalates are not required to be on product labeling.”