Category: Psychology

Are men and women’s brains really that different?

The brains of men and women are, on average, not that different, a new study finds.

The research focused on a brain structure called the hippocampus.

The hippocampus — which is vital for memory and other functions — was thought to be bigger in women than men.

A larger hippocampus was thought to explain why women have:

• better verbal memory,
• stronger interpersonal skills,
• and greater emotional expressiveness.

Men and women’s hipppocampi are a similar size, however, a team at the Rosalind Franklin University of Medicine in the US has found.

The study follows from others which have debunked other supposed differences between the brains of men and women:

• The corpus callosum — a structure which connects the brains’ two hemispheres — was thought to be different in men and women.
• The two hemispheres were thought to process language in different ways in men and women.

Both these claims have since been debunked.

Dr Lise Eliot, who led the study, said:

“Sex differences in the brain are irresistible to those looking to explain stereotypic differences between men and women.

They often make a big splash, in spite of being based on small samples.

But as we explore multiple datasets and are able to coalesce very large samples of males and females, we find these differences often disappear or are trivial.”

The study — a ‘meta-analysis’ — looked at 76 published papers which included results from over 6,000 people.

Dr Eliot continued:

“Many people believe there is such a thing as a ‘male brain’ and a ‘female brain.’

But when you look beyond the popularized studies — at collections of all the data — you often find that the differences are minimal.”

The study was published in the journal NeuroImage (Tan et al., 2015).

Wrong image from Shutterstock

People played ’20 questions’ using direct brain-to-brain connection.

Two human brains have been directly linked to play a game over the internet for the first time.

The experiment, carried out at the University of Washington, allowed people to send signals directly from one brain to the other over the internet.

Dr Andrea Stocco, the study’s first author, said:

“This is the most complex brain-to-brain experiment, I think, that’s been done to date in humans.

It uses conscious experiences through signals that are experienced visually, and it requires two people to collaborate.”

For the research, two people played a game similar to ’20 questions’ — a parlour game where you have to guess what object the other person is thinking of.

One person wore a cap measuring their brainwaves (EEG) and looked at a screen, on which was displayed an object, such as a dog.

They then responded to questions by focussing on one of two flashing LEDs.

Each were flashing at a different frequency and produced different types of brain waves.

When the sender looked at the ‘yes’ LED it activated (via the internet) a magnetic coil behind the receiver’s head.

This induced a phosphene — a line, wave or blob in the receiver’s visual field.

The results showed that in control experiments receivers guessed the correct object only 18% of the time.

But, when their brains were connected via the internet, the rate jumped to 72%.

The team are now working on the idea of sending whole brain states from one person to another.

For example, it may be possible to send signals from a healthy brain to someone who has suffered brain damage or has a developmental problem.

Dr Stocco said:

“Evolution has spent a colossal amount of time to find ways for us and other animals to take information out of our brains and communicate it to other animals in the forms of behavior, speech and so on.

But it requires a translation.

We can only communicate part of whatever our brain processes.

What we are doing is kind of reversing the process a step at a time by opening up this box and taking signals from the brain and with minimal translation, putting them back in another person’s brain.”

The study was published in the journal PLOS ONE (Stocco et al., 2015).

Network brain image from Shutterstock

People’s behaviour seems irrational but is governed by quantum principles.

The brain may behave like a quantum computer to help us cope with the complexities of life, a new theory argues.

Quantum cognition may help explain why people’s behaviour can often seem so irrational.

Dr Zheng Joyce Wang, one of the study’s authors, said:

“We have accumulated so many paradoxical findings in the field of cognition, and especially in decision-making.

Whenever something comes up that isn’t consistent with classical theories, we often label it as ‘irrational.’

But from the perspective of quantum cognition, some findings aren’t irrational any more.

They’re consistent with quantum theory — and with how people really behave.”

Some researchers are focusing on the idea that the brain is a kind of quantum computer.

Dr Wang and others, though, are taking a different approach.

They want to test whether the way people think has some similar patterns to those found in quantum mechanics.

For example, when we are trying to decide between two options, we see them in our mind at the same time.

Each one has all kinds of pros and cons attached to it — all sorts of probabilities about what might happen if we follow each path.

When we choose one, though, all these possibilities collapse into themselves.

Dr Wang explained:

“Our brain can’t store everything.

We don’t always have clear attitudes about things.

But when you ask me a question, like ‘What do you want for dinner?” I have to think about it and come up with or construct a clear answer right there.

That’s quantum cognition.”

It is reminiscent of the famous quantum mechanical thought experiment ‘Schrödinger’s cat‘.

Both quantum mechanics and quantum cognition are all about probabilities, but:

• Quantum physics deals with ambiguity in the physical world.
• Quantum cognition is about how our brains cope with ambiguity mentally.

In quantum mechanics it’s the probability that a particle will be in a particular place at a particular time, for example.

In quantum cognition it’s about the probability that we’ll make certain decisions.

Dr Wang said:

“In the social and behavioral sciences as a whole, we use probability models a lot.

For example, we ask, what is the probability that a person will act a certain way or make a certain decision?

Traditionally, those models are all based on classical probability theory — which arose from the classical physics of Newtonian systems.

So it’s really not so exotic for social scientists to think about quantum systems and their mathematical principles, too.”

Quantum cognition may explain some curious behaviours psychologists regularly see in their research, the researchers argue.

The theory is published in the journals Current Directions in Psychological Science and Trends in Cognitive Sciences (Busemeyer & Wang, 2015; Bruza et al., 2015).

Brain illustration image from Shutterstock

Alcohol changes the physical structure of certain neurons, neuroscientists find.

Neuroscientists have found a group of neurons which influence whether a couple of drinks turns into too many.

The discovery could be an important step forward in the fight against alcoholism.

The neurons — in part of the brain called the dorsomedial striatum — are vital to goal-directed behaviour.

Researchers found that alcohol changes the physical structure of these neurons.

Large amounts of alcohol, drunk periodically, activate dopamine receptors in this region, making them much more excitable.

Dr Jun Wang, the study’s lead author, said:

“If these neurons are excited, you will want to drink alcohol, you’ll have a craving.”

Activation of these neurons can motivate more drinking.

This in turn leads to the neurons being more sensitive.

So, it’s a vicious circle that’s difficult to escape from.

Neuroscientists reached these conclusions by carrying out experiments on mice.

They found that critical changes in so-called “D1 neurons” led to the mice consuming more alcohol.

Dr Wang said:

“Even though they’re small, D1 receptors are essential for alcohol consumption.

If we suppress this activity, we’re able to suppress alcohol consumption.

This is the major finding.

Perhaps in the future, researchers can use these findings to develop a specific treatment targeting these neurons.

My ultimate goal is to understand how the addicted brain works, and once we do, one day, we’ll be able to suppress the craving for another round of drinks and ultimately, stop the cycle of alcoholism.”

The research was published in the Journal of Neuroscience (Wang et al., 2015).

Alcoholic image from Shutterstock

Scientists were surprised by an unexpected effect of food on women’s romantic feelings.

Women feel more romantic after a meal than beforehand, a new study finds.

The results surprised researchers as typically people are more motivated when they are hungry.

Scientists scanned women’s brains when they were hungry and after they’d eaten.

During both scans women were shown ‘romantic images’.

Dr Alice Ely, the study’s first author, said:

“We found that young women both with and without a history of dieting had greater brain activation in response to romantic pictures in reward-related neural regions after having eaten than when hungry.

…eating may prime or sensitize young women to rewards beyond food.

It also supports a shared neurocircuitry for food and sex.”

People who have been on diets in the past are even more sensitive to rewards after eating.

Dr Ely said:

“In the fed state, historical dieters had a greater reaction in the reward regions than the other two groups to highly palatable food cues versus neutral or moderately palatable cues.

Based on this study, we hypothesized that historical dieters are differentially sensitive — after eating — to rewards in general, so we tested this perception by comparing the same groups’ brain activation when viewing romantic pictures compared to neutral stimuli in a fasted and fed state.

The pattern of response was similar to historical dieter’s activation when viewing highly palatable food cues, and is consistent with research showing overlapping brain-based responses to sex, drugs and food.”

The study was published in the journal Appetite (Ely et al., 2015).

Chilli mouth image from Shutterstock

How neuroscientists are learning to predict emotions with increasing accuracy.

Brain scans can read human emotions with 90% accuracy, a new study finds.

Researchers have been able to predict the intensity of negative emotions to evocative images.

They found that negative emotions have a ‘neural signature’ which a computer could learn.

Dr Luke Chang, who led the study, said:

“This means that brain imaging has the potential to accurately uncover how someone is feeling without knowing anything about them other than their brain activity.

This has enormous implications for improving our understanding of how emotions are generated and regulated, which have been notoriously difficult to define and measure.

In addition, these new types of neural measures may prove to be important in identifying when people are having abnormal emotional responses — for example, too much or too little — which might indicate broader issues with health and mental functioning.”

For the research, 182 people looked at photos designed to elicit a negative response.

These included pictures of physical injuries, hate groups and acts of aggression.

Using brain scans, a computer was able to learn the ‘neural signature’ of negative emotion.

Dr Chang said:

“We were particularly surprised by how well our pattern performed in predicting the magnitude and type of aversive experience.

As skepticism for neuroimaging grows based on over-sold and -interpreted findings and failures to replicate based on small sizes, many neuroscientists might be surprised by how well our signature performed.

Another surprising finding is that our emotion brain signature using lots of people performed better at predicting how a person was feeling than their own brain data.

There is an intuition that feelings are very idiosyncratic and vary across people.

However, because we trained the pattern using so many participants — for example, four to 10 times the standard fMRI experiment — we were able to uncover responses that generalized beyond the training sample to new participants remarkably well.”

The study was published in the journal PLOS Biology (Chang et al., 2015).

Crying image from Shutterstock

This common behaviour spreads like wildfire in the office.

Rudeness in the workplace is contagious, a new study finds.

Experiencing rude behaviour makes people more likely to expect it later on.

That expectation then causes people to behave more rudely to others.

The conclusions come from a psychology study of graduate students who were practising negotiation with their classmates.

The researchers found that people who negotiated with someone rated as rude were more likely to be rated as rude by someone else later on.

The effects held even when there was a week between the first and second negotiation.

Mr Trevor Foulk, one of the study’s authors, said:

“When you experience rudeness, it makes rudeness more noticeable.

You’ll see more rudeness even if it’s not there.”

Rudeness spreads so easily partly because people are remarkably tolerant of it, said Mr Foulk:

“Part of the problem is that we are generally tolerant of these behaviors, but they’re actually really harmful.

Rudeness has an incredibly powerful negative effect on the workplace.”

Rudeness also spreads easily because it primes our brains to detect rudeness.

In a further study, people who’d witnessed a rude interaction were quicker to pick out rude words from a list.

“That tells us that rudeness will flavor the way you interpret ambiguous cues.”

In other words: immediately after experiencing rudeness, you tend to be on the lookout for it.

Mr Foulk believes employers should take everyday incivilities more seriously:

“You might go your whole career and not experience abuse or aggression in the workplace, but rudeness also has a negative effect on performance.

It isn’t something you can just turn your back on.

It matters.”

The study was published in the Journal of Applied Psychology (Foulk et al., 2015).

Image credit: Gerolf Nikolay

Data from 350,000 people in over 100 different studies shows people are getting smarter — and this is why…

The more genetically diverse your parents are, the more likely you are to think quickly, a new study finds.

People whose parents are genetically dissimilar are also more likely to be taller.

The data comes from 350,000 people in over 100 different studies.

Researchers from the University of Edinburgh looked at similarities in the genetic code of people’s parents.

When parents share the same genetic code, this is a clue that they are (distantly) related.

Greater genetic differences, though, indicate that people’s parents are more likely to be unrelated.

Over time genetic diversity seems to be favouring people who are taller and think faster.

Dr Peter Joshi, of the University of Edinburgh’s Usher Institute, said:

“Our research answers questions first posed by Darwin as to the benefits of genetic diversity.

Our next step will be to hone in on the specific parts of the genome that most benefit from diversity.”

Dr Jim Wilson, at the same intitution, said:

“This study highlights the power of large-scale genetic analyses to uncover fundamental information about our evolutionary history.”

The study is published in the journal Nature (Joshi et al., 2015).

Brain growth image from Shutterstock

How to stop people carrying out unethical behaviours.

People who anticipate temptation are less likely to do bad things, a new study finds.

The research also found that when people thought unethical behaviour reflected poorly on them, they also resisted.

Dr Oliver Sheldon, one of the study’s authors, said:

“People often think that bad people do bad things and good people do good things, and that unethical behavior just comes down to character.

But most people behave dishonestly sometimes, and frequently, this may have more to do with the situation and how people view their own unethical behavior than character, per se.”

Part of the reason good people do bad things is that they rationalise, said Dr Sheldon:

“Unethical behavior may not be experienced as something that needs to be resisted if people think it’s socially acceptable or does not reflect on their moral self-image.

People often compartmentalize their experiences of temptation, making it much easier for them to rationalize the behavior.

They might say, ‘Just because I took office supplies home for personal use one time, that doesn’t mean I’m a thief.'”

In the study, people were given a series of everyday scenarios, like taking office supplies and calling in sick when not really ill.

The results revealed that people behaved more unethically if they believed the incident was isolated.

Dr Sheldon said:

“You may not be concerned about getting caught or about your reputation if people found out, but you might be concerned about your own ethical self-image.

Keeping such considerations in mind as one enters into potentially tempting situations can help people resist the temptation to behave unethically.”

The study was published in the journal Personality and Social Psychology Bulletin (Sheldon & Fishbach, 2015).

Halo image from Shutterstock

People move in herds — but simpler forces are at work than social pressure.

People copy each other all the time — it’s human nature.

The classic study, conducted in the 1950s by Solomon Asch, found that people will even deny the evidence of their own senses in order to copy other people (see: Conforming to the Norm).

But now a new study questions the established answer to exactly why people conform.

One of the new study’s authors, Diana Kim, explains:

“Social psychology has always explained conformity from social perspectives: group pressure, desire to belong to the group, belief in the group’s superior knowledge, etc.

The aim of the present study was to test whether even simpler mechanisms may account for at least some conformity effects.”

What they found was that the apparent desire for all humans to copy each other is not all about social pressure.

Maybe not even mostly about social pressure.

Instead the study suggests that behavioural decisions are a kind of ‘mental average’ of our own past behaviour plus that of other people.

We work out how to behave in a situation by recalling other people’s behaviour in the same situation…

…except we seem to get confused at recall and think that it was our own behaviour.

In other words: we copy other people, but forget that we are copying them, so it feels like our own decision.

The study is published in the journal Psychological Science (Kim & Hommel, 2015).

Seesaw image from Shutterstock