Friday, 9 October 2015

What is it like to experience mental illness?

Tomorrow, Saturday 10 October, is World Mental Health Day and to join in we've rounded up some of the research we've covered over the years that's explored what it's like to live with mental health problems, from obsessive compulsive disorder to hearing voices. Psychologists call these kind of studies "qualitative research", where the aim is not to put a score against particular symptoms, but to discover the first-hand perspective and experience of the people who take part, based on their own words. Such studies are often distressing to read, but their insights make a vital contribution to our understanding of the human condition.

Depression feels like a kind of emptiness
A recurring theme from interviews with seven people with depression was their sense of depletion and emptiness, both bodily and in thinking about the past and future. "It's like something's gone inside me and swept my happiness away," said one participant. "I feel like sometimes my life is on hold," said another. Isolation was another key theme, as captured by this man's description: "You get into a state I think mentally where, you're just like out on an island ... You can see from that island another shore and all these people are there, but there's no way that you can get across [ ] or there is no way that you want to get across." Writing in 2014, the researchers Jonathan Smith and John Rhodes said it was clear that all the interviewees had in common that they felt alone, empty and that they had no future.

Selective mutism does not feel like a choice
People with selective mutism can't speak in certain situations even though there is nothing physically wrong with their vocal chords and they don't have brain damage. Four people with the condition were interviewed via Skype's instant messenger interface. Their descriptions challenged the traditional idea that selective mutism is a choice. "It isn't me," said one participant. "I know who I am and I’m not shy or quiet, maybe that makes it harder. When I’m with my parents I can be myself but around everyone else it’s like it [selective mutism] takes over. I can get the words in my head but something won’t let me say them and the harder I try the more of a failure I feel like when I can’t." The interviewees also revealed how the condition became self-fulfilling as people came to expect them to stay silent. And they talked about the extreme loneliness they experienced. "It's like that scene from Scrooge where he looks through the window and he can see people having fun being together," said one interviewee. "I'll always be stuck outside looking in."

To be a refugee with psychosis is to feel there is no future
The first-hand experience of refugees with psychosis was documented for the first time in a heart-wrenching study published this year. Based on interviews with seven African refugees or asylum seekers, the researchers identified six main themes: bleak agitated immobility; trauma-related voices and visions (mostly the sounds or sights of lost relatives or attackers from the past); fear and mistrust; a sense of a broken self; the pain of losing everything; and the attraction of death. The last theme was captured by the words of 26-year-old Sando: "The worst part," he said, "is I keep harming myself, ... and you know knocking my head to the wall, kinda too much stuff in there, you know, I just want to open my head and finish with this."

Some people have a love-hate relationship with their OCD
Based on their hour-long interviews with nine people diagnosed with obsessive-compulsive disorder, the researchers Helen Murphy and Ramesh Perera-Delcourt identified three main themes: "wanting to be normal and fit in"; "failing at life"; and "loving and hating OCD." The first two themes were often related to the painful situations provoked by the interviewees' compulsions. One man who house-shared described how he had to scrub the entire bathroom with powerful cleaning product for an hour every day before he could use it. But at the same time, the interviewees explained how they actually feared losing the crutch that the condition provides. "I wish I could do that [stop checking], I wish I could stop," one man said, adding: "Well, not totally."

Being labelled as "schizophrenic" feels hugely stigmatising but also unlocks much-needed treatment
In a 2014 study, seven patients diagnosed with schizophrenia described their dilemma: they needed the diagnosis to access treatment, but had also feared and avoided the label because of the stigma associated with it. The interviewees said they tried to hide their diagnosis from people, and they noted how mental health professionals used alternative words like "psychosis" as if aware of the stigma of schizophrenia. "People are always afraid of saying that word to me," said said one woman, "... because it is a dirty word." The interviewees also described the chasm between their clinician's view of the illness as biological (a "chemical imbalance") and the perspectives of other people in their lives. "My mother ... all she said was 'I told you, it's because you're psychic ...," said another interviewee. The researchers said more needs to be done to overcome delays in treatment caused by ill people's fearful avoidance of a diagnosis.

For many self-harmers, seeing their own blood makes them feel calm
Among 64 self-harmers recruited from a mass screening of 1,100 new psychology students, just over half said that the sight of their own blood was important to them. The most common explanation the students gave was that seeing their blood made them feel calm. Other explanations were that it "makes me feel real" and shows that "I did it right/deep enough". Those students who highlighted the importance of seeing their blood tended to cut themselves more often than those who didn't (a median of 30 times compared with 4 times) and they were more likely to say they self-harmed as a way of regulating their own emotions. Another study from 2013 asked self-harming teenagers to carry a digital device for two weeks, in which to record their motives for self-harming as they occurred. Just over half the sample reported self-harming to achieve a particular sensation, the most common being "satisfaction", followed by "stimulation" and "pain".

Anorexia starts out feeling like a solution but then takes over
"Anorexia became a friend," said Natalie, one of 14 people recovering from anorexia who were interviewed as part of a study published in 2011. "When I was alone ... I knew that at least I had A." Eventually though, for Natalie and the others, anorexia became overpowering, almost like a separate entity which they had to fight against for control of their own mind. As Jon, another interviewee, put it: "It's like there are two people in my head: the part that knows what needs to be done and the part of me that is trying to lead me astray. Ana [his nickname for anorexia] is the part that is leading me astray and dominates me."

For people with Body Dysmorphic Disorder, mirrors are addictive and imprisoning 
A diagnosis of Body Dysmorphic Disorder is made when someone has a disabling and distressing preoccupation with what they see as their perceived physical flaw or flaws. In upsetting interviews that were published this year, 11 people with the condition described their complicated, troubling relationship with mirrors. One woman said she'd once stared into a mirror for 11 hours straight, searching for a perspective where she felt good enough about herself to be able to go out. Another interviewee, Jane, described mirrors as "f*cking bastards" and mirror gazing as a "form of self-harm". The interviewees also described what they perceived as the ugliness of the person staring back at them. "I look like a monster," said Hannah. Jenny said she is "truly hideous" and "repulsive". Lucy said: "Everyone else, everyone is beautiful. I just feel that I am that one ugly person."

People's experiences of hearing voices vary hugely 
Last year, researchers analysed seven previous studies that had explored people's first-hand experiences of hearing voices. Taken together, the most striking finding was that to hear voices that aren't there is not a homogenous condition. While most people described attributing an identity to the voices, they differed in whether they saw the voices as separate from their own thoughts or not, and in whether they felt in control of the voices. Those who subscribed to a biomedical account, believing that their voices were caused by a chemical imbalance in the brain, tended to feel less in control of their voices. Similarly, heard voices could interfere with social relationships, for example by making critical comments about friends or family. But voices could also play a beneficial role by reducing loneliness. "I have not got many friends … so the only thing I can stay very close to are the voices and I do stay very close to them," said one interviewee.

Positive change is a gradual process that is realised suddenly
As well as asking people about their experiences of mental illness, psychologists also research what the process of recovery feels like. In 2007, researchers interviewed 18 women and 9 men with conditions like depression and anxiety about their experiences of positive change during Cognitive Behavioural Therapy. “It was gradual but the realisation was sudden," one interviewee said. Many of the participants could remember the exact moment: “I could actually hear it,” one said. Other themes in the clients' descriptions of how change happened were: motivation and readiness (“I was desperate to get back to my old self”); tools and strategies (“It's the changes in behaviour that I learned”); learning (“I would take a lot of stuff home to read about assertiveness”); interaction with the therapist (“...they don’t judge your character or think they know you”); changes to self-perception (“I am a strong person mentally”); and the relief of talking (“Let me get everything out, let me relieve myself of everything”).

--further reading--
What is mental illness?
World Mental Health Day 2015
Post written by Christian Jarrett (@psych_writer) for the BPS Research Digest.

Our free fortnightly email will keep you up-to-date with all the psychology research we digest: Sign up!

Thursday, 8 October 2015

Psychologists study twins to learn more about the roots of procrastination

With so many digital distractions a mere mouse click away, procrastination is easier than ever. You want, nay need, to work on an important project, yet find yourself browsing Twitter, making coffee, checking email – basically anything other than doing what you should be doing. Daniel Gustavson and his colleagues – the authors of a new twin study of procrastination published in the Journal of Experimental Psychology: General – sum it up as "the irrational delay of an intended course of action".

Much has been written about why we fall prey to this habit in the moment (the all-important job is perceived as too challenging, the other tasks and distractions seem easier, and so on), but Gustavson and his colleagues wanted to learn more about why some of us are generally more prone to procrastination than others. Do we inherit a predisposition for procrastination in our genes, and what other mental abilities are related to the procrastination habit?

The researchers recruited 386 pairs of same-sex twins, 206 of whom were identical twins, meaning they have the same genes, and 179 were non-identical, meaning they share on average half their genes. After missing data were removed, the final sample included 401 women and 350 men (average age 23). The twins completed a questionnaire about their proclivity for procrastination (this involved rating their agreement with statements like "I am continually saying 'I'll do it tomorrow'"), and they answered questions about their proneness to "goal failures" (tested through questions like "Do you find you forget what you came to the shops to buy?").

The twins also completed several measures of their "executive function", including their powers of inhibition (e.g. one task involved resisting the reflex to glance at a square that appeared on-screen, and looking instead in the opposite direction), their ability to shift mind-sets (e.g. categorising shapes on a coloured background by their shape one minute, then by their colour, depending on changing task instructions), and their ability to juggle information in memory over short periods of time.

By comparing similarities in executive function performance, procrastination proneness and goal failures between identical and non-identical twins, the researchers were able to deduce how much of an influence genes have on these traits and abilities, and how much overlap there is in the genetic influence on the different measures. In simple terms, a higher correlation on a particular measure among identical twins compared with non-identical twins would indicate a greater role for genes.

Here are some of the key findings. The tendency to procrastinate was found to be partly inherited – 28 per cent of variability in this trait was explained by genetic influences (though note, this includes gene-environment interactions, such as a procrastinator choosing a job – like being a blog editor – that makes procrastination easier). Moreover, 17 per cent of the procrastination variability that was explained by genes overlapped with the genetic influences on goal failures – that is, many of the same genes influencing procrastination appear to play a role in the ability to manage goals. Also, environmental influences common to both procrastination and goal management explained a further 28 per cent of variation in procrastination.

The tendency to procrastinate also correlated with overall executive function ability – that is, people who said they procrastinated more tended to achieve an overall poorer score on the executive function tests. And again there was genetic overlap: many of the genetic influences on executive function were found to be the same as those shared by both procrastination and goal management.

There was one caveat in the association between procrastination proneness and executive function. Procrastinators actually tended to perform better on the ability to shift mind-sets, presumably because having a butterfly mind gives you a certain mental flexibility even though it makes it difficult to focus.

The findings help to pick apart the root causes of procrastination. At a genetic and behavioural level, they show that a tendency to procrastinate tends to go hand in hand with an ability to manage goals, and mostly a poorer ability to control one's own mind, in terms of inhibition and juggling information.

Gustavson and his team warned that identifying the actual genes involved in procrastination, executive function and goal management remains a long way of, and that many hundreds or thousands of gene variants are likely involved. They also cautioned that their study can't tell us about the causal relationships, if any, between the studied traits – it's tempting to assume that poor executive function or goal management causes procrastination, for example, but it's theoretically possible the influence could run the other way, both ways, and/or that other factors not studied here are more relevant, such as personality or intelligence. Nonetheless, the researchers did offer some brief practical advice on the back of their findings:
"Training subjects on how to set good goals may improve their ability to manage these goals and avoid procrastination ... Moreover, helping subjects retrieve their important long-term goals and use those goals to avoid getting side-tracked by short-term temptations (e.g. developing implementation intentions) might also be effective at reducing procrastination."

Gustavson, D., Miyake, A., Hewitt, J., & Friedman, N. (2015). Understanding the Cognitive and Genetic Underpinnings of Procrastination: Evidence for Shared Genetic Influences With Goal Management and Executive Function Abilities. Journal of Experimental Psychology: General DOI: 10.1037/xge0000110

--further reading--
The cure for procrastination? Forgive yourself!
Psychologists investigate a major, ignored reason for our lack of sleep - bedtime procrastination
Forgive yourself for relaxing in front of the TV and the couch time might actually do you some good

Post written by Christian Jarrett (@psych_writer) for the BPS Research Digest.

Our free fortnightly email will keep you up-to-date with all the psychology research we digest: Sign up!

Wednesday, 7 October 2015

Slot machines are more addictive when we see them as having human-like intentions

Slot machines are the great cash cow of the gambling industry, generating the bulk of income in casinos, and today they are also a feature of everyday life, found in high street pubs and bars and online. Slots are exquisitely designed with one purpose in mind, to encourage gamblers to "play to extinction" – that is, until they are penniless – as described at length in Natasha Dow Schüll's Addiction by Design: Machine Gambling in Las Vegas.

Much has been written about the human weaknesses, such as the gambler’s fallacy (believing that a win is more likely after a run of losses), that lead people to fall prey to these machines. Now new research published in the Journal of Experimental Psychology: Applied has identified a hitherto unexplored factor that makes it so tempting for people to just keep playing: “anthropomorphism” – it turns out we squander more on the slots when think of them as intentional adversaries.

The research led by Paulo Riva from the University of Milano-Bicocca asked student participants to play online slot machines for at least one spin, but longer if they wished, supposedly as market research on their design. In one condition participants first read a general description of how the machine is guided by a payout algorithm that produces successes and failures. But crucially, those in the anthropomorphic condition got a different message:
“The slot machine can decide whether you will win or lose a series of bets any time she wants. Sometimes, she may choose to make fun of you, leaving you empty-handed for several bets; other times, she might want to reward you with a win. In any case, the slot machine will always choose what will happen.”
Participants in this condition played for significantly longer, often a third or more extra spins (although there was a lot of variability between players within each of the conditions).

Further studies established that even with real incentives not to play – i.e. when any remaining points were converted to sweets or cash prizes – the personified machines still encouraged longer play. One clue as to why this happens is that play with personified machines was associated with stronger positive emotions – fun, excitement and stimulation. Riva’s team argue that feeling socially connected to an object (more likely when the object seems human-like) amplifies related emotions, giving a bigger kick to wins and losses. (Note that a larger final study complicated this story: positive strong emotions were again associated with playing for longer, but in this instance the anthropomorphism of slots didn’t increase positive strong emotions – this may be due to the different measure of emotion employed, but in any case calls for more research.)

Reflecting on the way slots are typically designed, with icons, characters and fictional tie-ins from Spiderman to Michael Jackson, the researchers suggest that "the gambling industry is selling customers a challenge against a mind rather than just a machine," introducing a competitive and even intimate element to play that helps clear out bank balances.

Before any strong conclusions are drawn, it would be useful to see this paradigm turned from student participants to regular gamblers. Casual gamblers may be drawn into the illusion of competition, but one of the most striking arguments from Schüll’s book is that the most compulsive gamblers devote themselves to the slots without expecting or even desiring a fair fight. For these people, playing the slots is a retreat from a life that’s hard to control, as the machines give them the opportunity to surrender to a comfortably predictable process: as one interviewee put it, “you accept the certainty of chance: the proof is the zero at the end.”


Riva, P., Sacchi, S., & Brambilla, M. (2015). Humanizing Machines: Anthropomorphization of Slot Machines Increases Gambling. Journal of Experimental Psychology: Applied DOI: 10.1037/xap0000057

Post written by Alex Fradera (@alexfradera) for the BPS Research Digest.

Our free fortnightly email will keep you up-to-date with all the psychology research we digest: Sign up!

Tuesday, 6 October 2015

The psychology of realising that you need psychological help

Of the many people with mental health problems who would likely benefit from psychological help, only a fraction actually find themselves face to face with a clinical psychologist or other kind of psychotherapist. There are of course practical reasons for this, including demand outstripping supply, but in many cases it also has to do with the perspective of the person who has the psychological difficulties. For example, a European survey published in 2009 found that of nearly 9000 people who showed evidence of clinically significant depression or anxiety, only a third thought that mental health services could help them.

A new study published in Clinical Psychology & Psychotherapy has lifted the lid on the psychological processes people go through in deciding that psychotherapy could be beneficial and arranging to begin treatment. Katherine Elliott and her colleagues assessed 155 people who'd made initial contact with psychological services at a university training clinic, including asking them how long they'd had their current mental health problems, how long it took them to decide that psychotherapy could help, how long they took to decide to seek therapy, and how long to arrange therapy. The participants were also followed up after their third therapy session and then again after they'd finished treatment.

The participants had had their current problems – mostly anxiety- or depression-related, but also including things like anger management and sexual problems – for an average of 10.5 years. They described the most difficult step towards starting treatment as deciding that psychotherapy might be beneficial. Once they realised they had a problem, it took the participants an average of four months to decide that psychotherapy might help (though this includes over 40 per cent who said it took a year or more to come to this realisation and 16 per cent who decided right away).

Once the potential benefits of psychotherapy were realised, each subsequent step became progressively quicker and easier. Deciding to actually go ahead and seek help took an average of a further month, and after that most participants said they took just a few weeks to make an appointment. However, it's striking that a quarter of the sample then failed to attend their first appointment.

Of the participants who did begin therapy, those who found deciding and arranging to start therapy more difficult also tended to expect the therapeutic process itself to be more difficult. Given that past research has shown people's expectations about therapy tend to correlate with the success of therapy, this sounds worrying. But actually this study found that expectations were not related to the participants' levels of commitment – a key factor in successful psychotherapy – once they had started their treatment (unfortunately there is no data on the actual outcomes of therapy).

This is a tricky topic to study: after all, we only have data here on people who made initial contact with psychological services so we've learned nothing about people with mental health difficulties who don't seek help. And we also don't know why a sizeable minority of the participants failed to begin therapy. That said, there are some useful insights here. In particular, the researchers said their results showed the most challenging and time-consuming aspects in seeking psychological help are often realising that one has a problem, and recognising that psychotherapy could be beneficial. Of course psychotherapy isn't for everyone. But spreading accessible information about mental health symptoms, and what psychotherapy entails and its potential benefits, could help a greater proportion of distressed people get the help they need.


Elliott, K., Westmacott, R., Hunsley, J., Rumstein-McKean, O., & Best, M. (2015). The Process of Seeking Psychotherapy and Its Impact on Therapy Expectations and Experiences Clinical Psychology & Psychotherapy, 22 (5), 399-408 DOI: 10.1002/cpp.1900

Post written by Christian Jarrett (@psych_writer) for the BPS Research Digest.

Our free fortnightly email will keep you up-to-date with all the psychology research we digest: Sign up!

Monday, 5 October 2015

How do popular kids behave in a cooperative task with a classmate?

Popular girls showed more skilful leadership than others, popular boys showed less. 
In classrooms around the world, there's an unwritten hierarchy, with most of the kids knowing each other's standing in terms of popularity. Past psychology research has looked into the ways that children and teens attain this status, including the ability to influence their peers, either in skilful, sensitive ways or through coercion and manipulation. A new study published in the Journal of Experimental Child Psychology takes a different approach by looking at how popular children, aged 11, behave when they participate in a one-on-one cooperative task with a randomly chosen classmate. Away from the eyes of the rest of the class, will they be rude and pushy, or show tact and leadership?

Tessa Lansu and Antonius Cillessen recruited 218 eleven-year-old girls and boys from nine schools in middle-class communities to complete a cooperative task in same-sex pairs. The task required each pair of children to sit at a computer together and fill out a form about planning a classroom party, including making decisions about the time and date, and what snacks would be on offer. A webcam recorded the discussions which took about ten minutes. Before this, all the children had answered questions about who was the most and least popular child in their class. The researchers used these ratings to ascertain each child's overall popularity.

Three judges coded the videos of the interactions for various behaviours, including skilful leadership (essentially when one child got the other one to follow their lead, but in a flexible way that took account of the other child's feelings and goals), overall influence, coercive or bossy behaviour and submissive behaviour.

Perhaps the most striking finding was the sex difference that emerged: the more popular girls were with their class as a whole, the more skilful leadership they showed in the cooperative task with a single class-mate. By contrast, boys' class popularity was associated with their showing less skilful leadership in the task. Overall, peer popularity was a more significant factor in the girls' interactions than the boys, also being associated with their having more influence and showing less submissive behaviour.

The researchers also looked at how a child's behaviour in the task was related to the popularity of their partner. Both girls and boys adopted a low profile when they were collaborating with a popular partner: they tended to avoid using coercion and any negative behaviour, suggesting they did not want to upset their popular classmate. "Interaction partners of high-status adolescents may keep a low profile because they are aware of the capabilities of the high-status influential peer," the researchers said. These results could also be interpreted the other way around, though, as showing that children were happier to bully and coerce classmates who were unpopular in class.

This is a very new area of study and there were some issues with the methods, including the fact the people coding the videos of the interactions didn't always agree on the nature of the behaviours on display. Also, the data only speak to the relevance of class popularity to behaviour in same-sex partnerships, and to behaviour in a cooperative task, as opposed to a competitive task or other one-on-one situation. Still, these are fascinating results ripe for follow-up. For example, can the observed sex differences be explained by possible differences in the ways girls and boys attain popularity: boys using group-level leadership, girls juggling numerous one-on-one relationships?

There could be practical insights here too. "If a teacher wants to promote assertiveness and leadership in a girl, having her work with a highly popular peer might not be the best option because the popular peer's reputation or behaviour could evoke submissive behaviour in the girl," the researchers said. "Instead, the teacher could pair her with an average-status peer, or maybe explicitly assign a more submissive role to the peer with whom she would be interacting, in order to promote the girl's assertiveness."

  ResearchBlogging.orgLansu, T., & Cillessen, A. (2015). Associations of group level popularity with observed behavior and influence in a dyadic context Journal of Experimental Child Psychology, 140, 92-104 DOI: 10.1016/j.jecp.2015.06.016

--further reading--
A child's popularity is related to where the teacher seats them in the classroom
What happens to the cool kids when they grow up?

Post written by Christian Jarrett (@psych_writer) for the BPS Research Digest.

Our free fortnightly email will keep you up-to-date with all the psychology research we digest: Sign up!

Saturday, 3 October 2015

Link feast

Our editor's pick of this week's 10 best psychology and neuroscience links:

Why It Was Easier to Be Skinny in the 1980s
People today are apparently about 10 percent heavier than people were in the 1980s, even if they follow the exact same diet and exercise plans. That's according to Olga Khazan who reports on an intriguing new study for The Atlantic.

Keeping a Spotless Mind: The Neuroscience of "Motivated Forgetting"
This year's joint annual British Academy/British Psychological Society Lecture was by Dr Michael Anderson and you can watch it on YouTube (also check out this report from Ella Rhodes at The Psychologist).

Confessions of a Neurotic Extravert
Psychologist Scott Barry Kaufman writes a deeply personal article for The Creativity Post.

A Glorious Hour
Colin Marshall at Open Culture looks back to 1924 when Helen Keller, who was deaf and blind, described the ecstasy of feeling Beethoven’s Ninth played on the radio.

Noël Carroll on the Paradox of Horror (video)
The desire to be scared or disgusted is odd. So why do audiences enjoy the unpleasant in horror fiction and film? From Aeon Video.

Blindsight: The Strangest Form of Consciousness
Some people who have lost their vision find a “second sight” taking over their eyes – an uncanny, subconscious sense that sheds light into the hidden depths of the human mind. By David Robson for BBC Future.

Drugs and Talk Therapy Affect the Brain in Different Ways
And sometimes they offer complementary benefits, suggests a new study that I reported on for New York's Science of Us.

The Problem of Too Much Talent
It’s true of basketball players, businesspeople, and even baboons: When too many powerful personalities are present, discord ensues. Adam Galinsky and Maurice Schweitzer report on their fascinating research for The Atlantic.

The 'No-Tech' School Where Screens Are Off Limits – Even At Home
Pupils at London Acorn School are banned from using smartphones and computers and watching TV at all times, including during holidays. Sally Weale visits the school for The Guardian.

Why Music?
A whole host of programmes on the psychology of music, from BBC Radio 3 and the Wellcome Trust.
Post compiled by Christian Jarrett (@psych_writer) for the BPS Research Digest.

Our free fortnightly email will keep you up-to-date with all the psychology research we digest: Sign up!

Friday, 2 October 2015

How jurors can be misled by emotional testimony and gruesome photos

As a juror in a criminal trial, you are meant to make a judgment of the defendant's guilt or innocence based on the evidence and arguments presented before you. In many trials, however, alongside the facts of the case, material and statements are allowed that don't in themselves speak to the culpability of the defendant. In a murder trial, for instance, a parent may take the stand and describe how their life has been destroyed by the loss of their child (the victim in the case). Similarly, the prosecution may present disturbing crime scene photographs of the victim, which don't say anything about the defendant's culpability, but do exert an emotional effect in the courtroom.

Writing in Psychiatry, Psychology and Law, Kayo Matsuo and Yuji Itoh at Keio University in Japan describe how they tested the effects of these kinds of evidence on the decision making of 127 students (89 women) who were asked to play the role of juror in a fictional case. The students listened to a man read out a transcript of a murder trial, in which a homeless man stood accused of murdering a young female student so that he would be sent to jail and no longer be homeless. Factually speaking the prosecution's case was weak, and while the defendant had confessed to the crime, he later recanted and pleaded innocence.

Among the students who heard a version of the trial transcript that featured no emotional testimony from the victim's father, nor any photos of the victim's body, 46 per cent of them said they thought the homeless man was guilty. Other students heard a version that did contain testimony from the victim's father, in which he expressed his grief, described how kind and bright his daughter was, and how much anger he felt toward the defendant. Although logically this testimony did not provide evidence of the defendant's guilt, 71 per cent of the students who heard the father's words said they thought the defendant was guilty, and this rose to 79 per cent if they were also shown photographs of the victim's fatally wounded body.

The effect of the father's emotional testimony appeared to be explained at least in part by the negative emotions it aroused in the students, such as anger and disgust. Among the students who rendered a guilty verdict those who heard the father's emotional testimony also tended to support a harsher sentence for the defendant – 33 per cent said he should receive the death penalty compared with just 16 per cent of those who did not hear the father's testimony. It's worth bearing in mind that the father's emotional testimony was read out to students by the narrator in a neutral voice – the psychological effects of this kind of testimony would likely be far greater in a real-life trial situation.

The researchers said their results showed that "emotional information upsets jurors and disturbs their legal decisions". They concluded that "in order to avoid false convictions and ensure a better trial system, psychological studies conducted in legal settings should explore the function of emotional evidence as well as the role of emotions."


Matsuo, K., & Itoh, Y. (2015). Effects of Emotional Testimony and Gruesome Photographs on Mock Jurors' Decisions and Negative Emotions Psychiatry, Psychology and Law, 1-17 DOI: 10.1080/13218719.2015.1032954

Post written by Christian Jarrett (@psych_writer) for the BPS Research Digest.

Our free fortnightly email will keep you up-to-date with all the psychology research we digest: Sign up!

Thursday, 1 October 2015

Toddlers have an instinct for fairness and generosity

Anecdotally, anyone who's spent time around toddlers knows that they mostly don't like sharing their toys. Together with research showing that toddlers, like adults, get pretty attached to their things and are reluctant to give them up, this has led to a popular belief that toddlers are selfish by nature.

But a team of developmental psychologists led by Julia Ulber has published new evidence in the Journal of Experimental Child Psychology that paints a more heart-warming picture. These psychologists point out that most past research has focused on how much toddlers share things that are already theirs. The new study looks instead at how much they share new things that previously no one owned. In such scenarios, toddlers frequently show admirable generosity and fairness.

There were two main experiments. The first involved 48 pairs of 18-month-old or 24-month-old toddlers sitting together at table, in the middle of which was a small container containing four marbles. If the toddlers took a marble and placed it in a nearby jingle box, it made a fun noise. The point of the set-up (repeated four times for each toddler pairing) was to see how the pairs of toddlers would divvy up the marbles between them.

Most of the time (44 per cent) the toddlers divided the marbles up fairly, 37 per cent of the time unequally (i.e. one child took 3 marbles), and 19 per cent of the time one child took all the marbles. This all took place pretty calmly, with marble steals happening only rarely. Overall, the experiment "rarely left one peer empty-handed," the researchers said, "and thus [the results] do not match the picture of the selfish toddler."

In a follow-up experiment with 128 pairs of two-year-olds, the set-up was more complex and this time, unlike the first experiment, none of the toddlers knew each other. Again, the children sat at opposite sides of a table with marbles on offer, but this time they had to pull a board sticking out of their side of the table to get the marbles to roll down into a reachable tray (marbles could again be used to make a jingle box play music). When the apparatus was designed so that there was one shared tray between the two toddlers, the toddlers shared the marbles equally about half the time. And this rose to 60 per cent if they'd had to collaborate by pulling the boards together to release the marbles.

In another variation of the set-up – possibly the most illuminating – the children had separate trays, and sometimes the researchers made it so that one child received three marbles in their tray and the other child just one. On about one third of these occasions, the results were delightful – the "lucky child" with three marbles gave up one of their marbles to their partner, willingly and unprompted. "This is the youngest age ever observed at which young children make sacrifices in order to equalise resources," the researchers said.

These acts of fairness were greater when the marbles were colour-coded so that two marbles matched the colour of one child's jingle box (located behind them) and the other two matched the other child's.  This colour-coding effect on generosity might be due to the children interpreting the colours as a sign of ownership (i.e. the idea being that this or that marble belongs to the other child because it matches their jingle box), or the colours might simply have helped the children, with their limited numerical skills, to identify a fair split in the numbers of marbles.

The researchers said their results showed that "young children are not selfish, but instead rather generous" when they're sharing resources among themselves, and that more research is needed to establish "in more detail the prosocial or other motives that influence the way in which young children divide resources."


Ulber, J., Hamann, K., & Tomasello, M. (2015). How 18- and 24-month-old peers divide resources among themselves Journal of Experimental Child Psychology, 140, 228-244 DOI: 10.1016/j.jecp.2015.07.009

--further reading--
Comparing children's sharing tendencies across diverse human societies
How to increase altruism in toddlers
Most acts of aggression by toddlers are unprovoked

Post written by Christian Jarrett (@psych_writer) for the BPS Research Digest.

Our free fortnightly email will keep you up-to-date with all the psychology research we digest: Sign up!

Wednesday, 30 September 2015

They deny it, but the middle classes have a subconscious positive bias toward the rich

"Eat the rich, it’s all that they’re good for" is a refrain familiar to my growing-up-in-the-90s ears. To many people today, the upper classes remain fair game for criticism, whether derided as Ivy-League elites, tax-dodging CEOs, or the undeserving gentry. But although many of us may claim to hold negative views about the wealthy, a new study published in Group Processes and Intergroup Relations says our implicit preferences tell a different story. A story we might call "Confessions of a secret rich-lover" …

Across the experiments we’re about to discuss, the participants – US adults recruited online mainly from the middle class – explicitly disclaimed holding those higher on the economic ladder in high esteem. For instance, they were more likely to agree with items like “I don’t like rich people very much” than to similar items referring to the middle class. Middle class beats the rich, on the surface. But what lies beneath?

To find out, Yale researchers Suzanne Horwitz and John Dovidio had participants complete a version of the Implicit Association Test (IAT), which has been used by psychologists in the past to reveal people’s race-, age-, and sex-based biases, and more recently negative attitudes to the poor. In this test, participants have to use just two computer keyboard keys to categorise words flashed on-screen. The standard categories are "good" words (e.g. wonderful, excellent) and "bad" (e.g. horrible, nasty), and the participants’ task is to respond as fast as possible, pressing the key for the good category when they see what they consider a good word and the key denoting the bad category when they see a bad word.

Specific to this study, other words in the same test had to be classed as fitting a rich category (e.g. high income, upper class, rich) or middle class category (e.g. average income, middle class, typical), using the same two keys that were also used for categorising good and bad words. Crucially, when categorising a word as rich or good required use of the same key, faster participant performance (vs. when the rich and bad categories were paired with the same key) would suggest that participants subconsciously considered being rich as a good thing rather than a bad thing. And indeed, across the four experiments, participants showed such a positive bias toward the rich, which was larger than the bias they showed towards their own group of the middle class.

In one experiment, participants completed two IATs, one as described and another pitting attitudes toward the middle class against those toward the poor. Horowitz and Dovidio wondered whether favouring the rich and disliking the poor were intertwined attitudes or independent – as is the case in attitudes towards weight, where pro-thinness is distinct from anti-fatness. Analysis showed that IAT anti-poor scores didn’t predict IAT pro-rich scores – and in fact, explicit attitudes to rich and poor were also independent, suggesting these attitudes are also distinct – in other words, just because a person was subconsciously or overtly pro-rich, it didn’t follow that they would also be subconsciously or overtly anti-poor (or vice versa).

A final experiment suggested that, given the right conditions, our implicit feelings toward the rich predict how we judge various social situations. Another 78 middle-class participants read a vignette in which two risk-taking drivers collide – a wealthy one in a Jag roadster, the other, middle class in an old Toyota – and then they rated each driver independently on how blameworthy, careless and bad they were. Explicit attitudes weren’t related to their judgments, but IAT performance was – those participants with a larger pro-rich bias on the IAT were softer towards the Jag driver. Given debate about whether implicit attitudes are effective in predicting wider consequences, this finding is important, although we should note the vignette was carefully designed not to trigger stereotype-related explicit attitudes that might swamp the effect; we might expect a different pattern for other situations, such as a rich person coldly ignoring a request for help.

Why do middle-class people harbour deep-seated positive regard for the rich? Unlike with other non-majority groups, the wealthy benefit from historically positive representations. Lay this alongside the popular idea of meritocracy – you get what you deserve – and it’s clear how implicit esteem for the rich might drip-drip in. Furthermore, many people, especially in the US, are incentivised against hardening their hearts to the rich – due to the hope that one day, they’ll be living next door to them.


Horwitz, S., & Dovidio, J. (2015). The rich--love them or hate them? Divergent implicit and explicit attitudes toward the wealthy Group Processes & Intergroup Relations DOI: 10.1177/1368430215596075

--further reading--
Students motivated by wealth are just as likely as others to help in an emergency
The downside of being good-looking AND wealthy
Seeing others as less than human

Post written by Alex Fradera (@alexfradera) for the BPS Research Digest.

Our free fortnightly email will keep you up-to-date with all the psychology research we digest: Sign up!

Monday, 28 September 2015

New genetic evidence suggests face recognition is a very special human skill

Example stimuli from Shakeshift and Plomin, 2015.
A new twin study, published today in PNAS, of the genetic influences on face recognition ability, supports the idea that face recognition is a special skill that's evolved quite separately from other aspects of human cognition. In short, face recognition seems to be influenced by genes that are mostly different from the genes that influence general intelligence and other forms of visual expertise.

The background to this is that, for some time, psychologists studying the genetics of mental abilities have noticed a clear pattern: people's abilities in one domain, such as reading, typically correlate with their abilities in other domains, such as numeracy. This seems to be because a person's domain-specific abilities are strongly associated with their overall general intelligence and the same genes that underlie this basic mental fitness are also exerting an influence on various specific skills.

Nicholas Shakeshaft and Robert Plomin were interested to see if this same pattern would apply to people's face recognition abilities. Would they too correlate with general intelligence and share the same or similar genetic influences?

The researchers recruited 2,149 participants, including 375 pairs of identical twins who share the same genes, and 549 non-identical twins, who share roughly half the same genes, just like typical siblings (overall the sample was 58 per cent female with an average age of 19.5 years). The participants completed a test of their face processing skills, including memorising unfamiliar faces, and also tests of their ability to memorise cars, and their general intelligence, in terms of their vocabulary size and their ability to solve abstract problems.

Comparing the similarities in performance on these different tests between identical and non-identical twin pairs allowed the researchers to estimate how much the different skills on test were influenced by the same or different genes.

All the abilities – face recognition, car recognition and general mental ability – showed evidence of strong heritability (being influenced by genetic inheritance), with 61 per cent, 56 per cent, and 48 per cent of performance variability in the current sample being explained by genes, respectively.

Crucially, performance on face recognition was only moderately correlated with car recognition ability (r = .29 where 1 would be a perfect correlation) and modestly correlated with general mental ability (r = .15), and only 10 per cent of the genetic influence on face recognition ability was the same as the genetic influence on general mental ability (and likewise, only 10 per cent of the genetic influence on face memory was shared with the genes affecting memory for cars).

Essentially, this means that most of the genetic influences on face recognition ability are distinct from the genetic influences on general mental ability or on car recognition ability. Shakeshaft and Plomin said this "striking finding" supports the notion that there is something special about human facial recognition ability. These results add to others that have suggested face recognition is a special mental ability – for instance, some have argued that faces alone trigger brain activity in the so-called "fusiform face area" (although this claim has been challenged); and unlike our ability to recognise other objects or patterns, our ability to recognise faces is particularly impaired when faces are inverted, consistent with the idea that we use a distinctive "holistic" processing style for faces.

The story is complicated somewhat by the researchers' unexpected finding that recognition ability for cars was also linked with distinct genetic influences that mostly did not overlap with the genetic influences on general mental ability. Perhaps, the researchers surmised, the tests of general mental ability used here (a vocab test and the well-used Raven's Progressive Matrices) did not adequately tap the full range of what we might consider general mental abilities. Whatever the reason, it remains the case that this new research suggests that face recognition ability is influenced by a set of genetic influences that are largely distinct from those implicated in a similar form of visual recognition (for cars) and implicated in vocab ability and abstract reasoning. Based on this, the researchers concluded they'd shown for the first time that "the genetic influences on face recognition are almost entirely unique."


Nicholas G. Shakeshaft, & Robert Plomin (2015). Genetic specificity of face recognition PNAS

Post written by Christian Jarrett (@psych_writer) for the BPS Research Digest.

Our free fortnightly email will keep you up-to-date with all the psychology research we digest: Sign up!

Extraverts are surprisingly good at mind-bending puzzles

The solitary inventor, buried away in garage or shed, is the classic depiction of introvert as born problem-solver. But new research, published recently in Psychological Studies, suggests that it’s extraverted people who perform better at classical tests of problem-solving, thanks to their tendency to be motivated in ways that are helpful for achieving.

Vidya Athota at the University of Notre Dame, Australia and Richard Roberts at the Center for Innovative Assessments in New York ran computerised sessions of the Tower of Hanoi test (see a model below), in which participants disassemble a tapering tower of disks threaded onto a pole, in order to eventually reassemble them into a new tower on another pole. To do this, they make use of a third, spare pole to help fulfil the task rule that in forming the new tower you must only lay new discs onto larger ones.

Image: Ævar Arnfjörð Bjarmason/ Wikipedia
The 195 student participants tried to solve as many rounds of this that they could in three minutes, and also completed questionnaires on personality and personal values, specifically pleasure-oriented and service-oriented approaches to the world (essentially measuring how much they prioritised having fun in life versus concern for the welfare of others).

Athota and Roberts found the more extraverted participants solved more Towers of Hanoi, but only because they tended to be more interested in pursuing pleasure in the form of sensual gratification and especially stimulation and excitement. When these two values were accounted for, extraversion in itself didn’t provide extra predictive power.

At first blush, stimulation and sensual gratification sound like drives that would lead people away from cracking codes and straight onto a rollercoaster, no seatbelt required, thanks. But cognitive work that promises a satisfying payoff is facilitated by a higher appetite for rewards, which seems to be what we’re seeing here, with participants marshalling their focus and mental resources to beat the tower as often as possible.

By revealing why extraverts tackle certain tasks better, this study helps us figure out when they may not. Being strongly attracted to pleasure is associated with extraversion, but the promised thrill of success won’t be prominent in every creative challenge – problem solving is often about more than tackling circumscribed puzzles – so we shouldn’t expect extraverts to excel on all challenges. That said, when we look at this issue from other angles – such as the types of people who make more creative scientists – extraverts also defy expectations, tending to be among the most creative. Just as the notion that extraverts always make better salespeople is mistaken, we should be aware that think-work is not the sole domain of the introvert, but will suit different personality types better according to the specific characteristics of task, incentives, and social environment.


Athota, V., & Roberts, R. (2015). How Extraversion + Leads to Problem-Solving Ability Psychological Studies, 60 (3), 332-338 DOI: 10.1007/s12646-015-0329-3

Post written by Alex Fradera (@alexfradera) for the BPS Research Digest.

Our free fortnightly email will keep you up-to-date with all the psychology research we digest: Sign up!