Reminder of disease primes the body and mind to repel other people

When it comes to avoiding infection, a growing body of evidence suggests we don't just have a physiological immune system, we also have a behavioural immune system - one that alerts us to people likely to be carrying disease, and that puts us off interacting with them. Indeed, there's research showing that people who are more fearful of disease tend to hold more xenophobic attitudes and to display greater prejudice towards people with outwardly visible disabilities. Now Chad Mortensen and his co-workers have extended this line of research by showing that a disease-themed slide show makes people feel less sociable and extravert, and primes their motor system for repelling other people.

In the first study, half of 59 participants watched a disease and infection-themed slide show before completing a measure of their own personality. The other participants watched a slide show about architecture before doing the same. The researchers took pains to conceal the true purpose of the study. They asked participants to rate the slide shows' usefulness for another project and they had them answer irrelevant questions. The key finding was that participants who watched the disease slide show subsequently rated themselves as less extravert than did the control participants. Also, among those participants who scored highly on a measure of fear of disease, those who watched the infection slide show rated themselves afterwards as less open to experience and less agreeable. Taken altogether this suggests that reminders of disease makes us view ourselves as less outgoing and gregarious, especially if we're the kind of person who's already fairly neurotic about infection.

If these effects are real, you'd expect them to have some effect on actual behaviour. The second study tested that by having participants watch one of the slide shows before completing a computer task. The task involved faces and shapes flashing on a screen and participants responding with a button press that required either an extension or contraction of the arm. The take-home finding here was that participants who watched the disease slide show were quicker at the button presses that required them to extend their arm - the same muscle action that would be required to push someone away. This effect was particularly strong among those participants who were more scared of infection. Again, cover stories were used to conceal the true purpose of the study.

'...It appears that humans have evolved a mechanism that responds to environmental cues of disease and modulates attitudes and behaviours in functionally appropriate ways,' the researchers said.

Looking to the future, Chad Mortensen and his colleagues added that it would be interesting to see if there could be a reverse effect in conditions in which risk of infection appeared to be absent. In this case, people normally afraid of infection might become particularly extravert and sociable.
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Mortensen, C., Becker, D., Ackerman, J., Neuberg, S., & Kenrick, D. (2010). Infection Breeds Reticence: The Effects of Disease Salience on Self-Perceptions of Personality and Behavioral Avoidance Tendencies. Psychological Science, 21 (3), 440-447 DOI: 10.1177/0956797610361706

Related open-access article in The Psychologist magazine: 'Parasites, minds and cultures'.

Extras

Eye-catching studies that didn't make the final cut:

A Systematic Review of Six Decades of Research in Psychopharmacology. Verdict: Huge improvements over time, but could still do better.

When exposed to scary stimuli, anxious people experience a more pronounced sense of time slowing down than do calmer people. [now open access]

The man who lost his ability to see colours, but didn't know it. Or, in the scientific jargon: 'Anosognosia for cerebral achromatopsia'.

The neuroscience of human intelligence differences.

Women's faces judged more attractive when making eye contact rather than looking a way. [now open access]

You know when the sun makes you sneeze? This study uses EEG to look at the neural basis of this phenomenon.

New Lancet review of the placebo effect.

'Touch establishes powerful physical and emotional connections between infants and their caregivers, and plays an essential role in development' Systematic review of infant massage.

Meta-analysis finds violent videogames can lead to increased aggression.

The remote rural community that thinks letting someone die is as bad as killing them

In recent years, cognitive scientist Marc Hauser has gathered evidence that suggests we're born with a moral instinct. This moral intuition has been likened to the universal grammar that Chomsky famously suggested underlies our linguistic abilities - certain principles are set in stone, whilst the precise parameters can be set by culture. Thousands of people from multiple countries and different religions and demographic backgrounds have given their verdict on fictional scenarios presented online and from this Hauser has identified some potential moral universals [try out the moral tests for yourself].

One of these near-universal principals is that most people think it is worse to deliberately cause someone harm in order to achieve a greater good, than it is to cause some harm as a side-effect in pursuit of the greater good. Think of deliberately pushing a man in the way of a run-away lorry to save a crowd, as opposed to shouting at the lorry driver, such that he swerves away from the crowd, but instead crashes into and kills a man on the pavement.

Another is that most people think actions that lead to harm are worse than omissions (i.e. not doing something) that lead to harm. Think of a doctor killing a patient with a lethal dose, as opposed to letting them die by not administering a life-saving drug.

Finally, most people think harm delivered via direct physical contact - for example, pushing them to their death - is worse than harm delivered at a distance - for example, via a trap.

Most people match this pattern of responding but so far most participants have been from urban, technologically advanced cultures. Now Marc Hauser and his colleague Linda Abarbanell have translated these kinds of moral scenarios and taken them to a rural Mayan community in the highlands of Chiapas in Mexico.

The rural Mayans showed the usual bias for seeing harm caused deliberately in pursuit of a greater good as more forbidden than harm caused as a side-effect in pursuit of that same greater good. But Abarbanell and Hauser's breakthrough finding is that the rural Mayans didn't believe that harm caused by direct contact was worse than indirect harm and they didn't think active harmful acts were morally worse than harmful acts of omission.

The researchers don't think these differences emerged because of translation problems. Choosing to focus on the omission/active harm type situation, the researchers tried out several different scenarios, including one designed for use with children, and always the results were the same. The rural Mayans saw agents as more causally responsible for active harm, they just didn't see them as more morally blameworthy. Moreover, when Abarbanell and Hauser tested a more urban Mayan population, they did show the usual tendency to see harmful acts of omission as less bad, thus suggesting that this difference in moral judgment is specific to the rural community.

They don't have a specific law that forbids 'looking the other way', so why should the rural Mayans differ on this key moral principle? The researchers said more research is needed, but they think it probably has to do with the 'highly intertwined social relations and their associated obligations' in the rural Mayan society. Future studies could look to see if the omission/active harm distinction is missing from other small-scale, close-knit societies.

'Ultimately,' Abarbanell and Hauser concluded, 'this research may suggest that some psychological distinctions are moral absolutes, true in all cultures, whereas others may be more plastic, relative to a culture's social dynamics, mating behaviour and belief systems.'
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Abarbanell, L., & Hauser, M. (2010). Mayan morality: An exploration of permissible harms. Cognition DOI: 10.1016/j.cognition.2009.12.007

Image credit: Wikipedia commons.

We're slower at processing touch-related words than words related to the other senses

People are slower at responding to tactile stimuli than to input from the other senses. It's not immediately obvious why this should be. It's unlikely to be for mechanical reasons: the retina in the eye is slower at converting input into a neural signal than is the skin. Psychologists think the answer may have to with attention. Perhaps we're not so good at keeping our attention focused on the tactile modality compared with the others. Now Louise Connell and Dermot Lynott have added to the picture by showing that the tactile disadvantage extends to the conceptual domain. That is, we seem to be slower at recognising when a word is tactile in nature than we are at recognising whether words are visual, to do with taste, sound, or smell.

The researchers had dozens of participants look at words on a screen, presented one at a time, and press a button to say if they were related to the tactile modality (e.g. 'itchy') or not. Some words were tactile-related whilst others were fillers and related to the other senses.

The same task was then repeated but with participants judging whether the words were visual-related, auditory and so on, with each sense dealt with by a new block of trials. The key finding is that participants were much slower at this task in the tactile condition than for the other senses. This was the case even when words were presented for just 17ms, which is too fast for conscious detection but long enough for accurate responding.

To make sure the slower performance in the tactile condition wasn't to do with the response requiring a button press (which inevitably causes tactile stimulation), the researchers repeated the experiment with vocal responding via a microphone. The results were pretty much the same.

Ensuring they left no stone unturned, Connell and Lynott also conducted a final experiment to check that there isn't something about tactile words, besides their touchiness, that makes them slower to process. To do this they used words that have both visual and tactile qualities - examples include shaggy and spiky - and they mixed these in among filler words that related to the other senses. The same words were used in the tactile condition (in which participants had to say whether each word was tactile-related or not) and a visual condition. Once again, participants were significantly slower in the tactile condition.

Connell and Lynott say their findings provide further evidence for the tactile sense having a processing disadvantage relative to the other senses. They think this is because there's little evolutionary advantage to sustaining attention to the tactile modality whereas there are obvious survival advantages with the other senses, for example: '...in hunting, where efficacious looking, listening and even smelling for traces of prey could afford an advantage.' You may think of pain and damage detection as reasons for paying sustained attention to the tactile domain, but remember these are served by spinal reflexes. 'We do not wait for the burning or stinging sensation to register with the attentional system before responding,' the researchers said.
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Connell L, & Lynott D (2010). Look but don't touch: Tactile disadvantage in processing modality-specific words. Cognition, 115 (1), 1-9 PMID: 19903564

Darkness encourages unethical behaviour even when it makes no difference to anonymity

Imagine a man sits alone, hunched over his desk, fingers tapping out a project progress report to his boss. Does he decide to lie? If I told you that the sun had nearly set, filling the man's room with darkness, would that make any difference to your answer? It should do. A new study suggests that darkness encourages cheating, even when it makes no difference to anonymity.

Chen-Bo Zhong and colleagues had dozens of undergrad students complete a basic maths task against a time limit. Afterwards they had to fill in an anonymous form indicating how many items out of twenty they'd answered correctly and they had to take a monetary reward from an envelope (up to twelve dollars) in line with their performance. Half the students completed the task in a dimly lit room (though still light enough to see each other) whilst the other half completed the task in a bright room.

A surreptitious coding system allowed the researchers to match up the students' self-completed scoring cards with their actual performance. You guessed it, the students in the dimly lit room tended to exaggerate their performance more than the control group in the bright room (by an average of 4.21 items vs. 0.83 items). Another way of looking at it is that 60.5 per cent of participants in the dim room exaggerated their performance compared with just 24.4 per cent of participants in the bright room.

In the same way that young kids think they are invisible when they cover their eyes, Chen-Bo Zhong's team think the effect they observed occurs as an automatic response to the cover of darkness, even when the lack of light makes no difference to anonymity.

A second study supported this interpretation, finding that student participants wearing sun-glasses chose to share money less fairly in a computer-based economic game than did students wearing normal glasses. Again, the subjective reduction in light made no difference to actual anonymity as the game was played entirely via computer with a partner who participants thought was in another room. The students who said they felt more anonymous tended to share the least money, thus suggesting that perceived anonymity was mediating the effect of darkness on behaviour.

'Darkness appears to induce a false sense of concealment, leading people to feel that their identities are hidden,' the researchers said. The next time you're deliberating over a moral issue, you might want to think about whether you've got the lights on or not!
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Zhong, C., Bohns, V., & Gino, F. (2010). Good Lamps Are the Best Police: Darkness Increases Dishonesty and Self-Interested Behavior. Psychological Science DOI: 10.1177/0956797609360754

The Special Issue Spotter

We trawl the world's journals so you don't have to:

Delusion and Confabulation (Cognitive Neuropsychiatry).

Formal modeling of semantic concepts (Acta Psychologica).

Silence and Memory (Memory). From the editorial: 'As memory researchers particularly, and psychological researchers more broadly, we often focus our observations on what is present—what is expressed, what is rehearsed, what is reported. This special issue of Memory focuses on silence and its implications for memory, and also for the implications of silences that extend beyond memory, to the functioning of individuals, groups, and societies.' Sounds intriguing.

Language, Communication and Schizophrenia (Journal of Neurolinguistics).

New Aspects in the Treatment of Affective Disorders (The International Journal of Neuropsychopharmacology). Open Access issue.

Hour-glass figure activates the neural reward centre of the male brain

There's little doubt that many conceptions of attractiveness are faddish - the size zero female model being an obvious example. However, other notions of beauty are more hard-wired, perhaps reflecting an evolutionary adaptation. These aspects of appearance have come to be associated with fertility, signifying 'reproductive fitness' to potential mates. Male facial symmetry is one example. Another is the hour-glass female form. Men in cultures across the world report a preference for women with a lower waist-to-hip ratio. And women with this body shape tend to be more fecund.

Now Steven Platek and Devendra Singh have provided brain imaging evidence to complete the picture. They've shown that the reward centres of men's brains fired up in response to the sight of naked women who'd chosen to have cosmetic surgery to accentuate the curviness of their figures. By contrast, changes to the women's body mass index - including increased slimness - had no such effect. Platek and Devendra said the finding could explain 'some men's proclivity to develop preoccupation with stimuli depicting optimally designed women' - i.e. porn. The weaker neural response to slimness, by contrast, suggests 'BMIs role in [attractiveness] evaluations is less the product of evolved psychological mechanisms and more the part of culturally driven, or societal based norms and perceptions.'

Platek and Singh made their observations after asking men to look at photographs of women taken before and after they'd undergone surgery in pursuit of an hour-glass figure. The post-op pictures triggered more brain activity in reward-evaluation areas such as the orbitofrontal cortex. The surgery had the effect of lowering the women's waist-to-hip ratio and there were also slight changes to their BMI scores. The former change was associated with more reward-related activity in the men's brains whereas changes to BMI was only associated with activity adjustments in lower-level visual brain areas. Finally, increases in the attractiveness ratings given by the men to the post-op pictures were associated with activation in neural reward areas, such as the nucleus accumbens, which are also involved in drug-based reward and craving.
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Platek, S., & Singh, D. (2010). Optimal Waist-to-Hip Ratios in Women Activate Neural Reward Centers in Men. PLoS ONE, 5 (2) DOI: 10.1371/journal.pone.0009042

Can therapists tell when their clients have deteriorated?

About five to ten per cent of the time, people in therapy get worse instead of better. What should psychotherapists do in such cases? Hang on a minute. There's no point answering that question unless therapists can recognise that a client has deteriorated in the first place. A new study tackles this precise issue, finding, rather alarmingly, that the vast majority of therapists appear blind to client deterioration.

Derek Hatfield and colleagues took advantage of therapy outcome data gathered at a student counselling centre where clients provided symptom feedback prior to each weekly session. Although placed on record, this outcome data wasn't fed back to the therapists in a systematic way and there was no alert in place to signal symptom deterioration (as an aside, past research shows such systems hugely improve therapy outcomes). Rather, the therapists, the majority of whom had PhDs or were in doctoral training, had to rely on their own judgment.

Hatfield's team identified 70 clients who at one particular session were in significantly worse shape compared with their state before entering therapy, prior to the very first session. The researchers then scrutinised clinical notes made by the therapists after each session to see if, at the appropriate session, they'd made any reference to their clients' worsened state. Here's the shocker: in only 15 of these 70 cases had the therapists made a clinical note after the relevant session suggesting they had noticed a deterioration.

Therapists often have massive case loads and in some cases the deterioration could have occurred some weeks after the opening session. Perhaps it is no wonder that most therapists had struggled to notice negative change. To make things easier, Hatfield and his co-workers returned to the database and focused on just those cases where a client had shown a huge deterioration from one session to the next. Unfortunately, it's still bad news. Of these 41 cases, therapist notes suggested they noticed only 13.

The question of what psychotherapists should do when a client deteriorates is for fuller discussion another day. However, Hatfield did touch on this. On those occasions that therapists had noted a client deterioration, Hatfield's team looked to see what the noted course of action had been. The most common choices were drug referral and continue as usual. Hatfield then surveyed hundreds of APA-registered psychological therapists about what they would do, hypothetically speaking, if they had a client who'd deteriorated. Revealingly, among those 36 who replied, popular answers included 'discuss the deterioration with the client' and 'increase therapy sessions'. Worryingly perhaps, these suggestions were noticeably absent from the real life case notes.

This research comes with a major caveat - dependence on therapists' clinical notes is a far from perfect indicator of whether or not they noticed client deterioration. Still, you'd expect a significant worsening, if noticed, to be noted. The researchers said: 'It is hoped that therapists will be open to the idea that additional information concerning client progress will enhance their clinical judgment, particularly concerning potential client deterioration.'
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Hatfield, D., McCullough, L., Frantz, S., & Krieger, K. (2009). Do we know when our clients get worse? An investigation of therapists' ability to detect negative client change. Clinical Psychology & Psychotherapy DOI: 10.1002/cpp.656

Video-game exercise bikes - not just a gimmick

Exercise is going techno. People are playing Wii fit sports games in their homes and gyms are full of ever more interactive exercise machines. But is this trend anything more than gimmickry? Yes, according to a new study by Ryan Rhodes at the Behavioural Medicine Lab at the University of Victoria, and his colleagues.

Rhodes' team had 29 previously inactive young men embark on an exercise regime, involving three half-hour cycling sessions a week for six weeks. Crucially, half the men trained on GameBikes wired up to a Playstation, such that their peddling speed and steering interacted with in-game events. The remaining participants trained on standard low-tech exercise bikes, although they were allowed to enjoy their own choice of music over an ipod. Exercise intensity was equalised across the two groups.

The bottom-line: the men who trained on the GameBikes were more likely to stick to the exercise regime. They attended an average of 77 per cent of the sessions compared with 42 per cent of participants in the low-tech control condition.

Rhodes' team also took some psychological measures in line with the well-established theory of planned of behaviour. Only 'affective attitudes' were found to differ between the two exercise groups. That is, men in the GameBike condition expected the exercise regime to be more enjoyable, pleasant and exciting than control participants, partly explaining their greater adherence. Attitudes in both groups had declined by the end of the six-week period, but they remained more positive in the GameBike group than the controls.

The researchers said more research was needed with other participant groups (the men in the current study all had personal experience of video games), over a longer duration, and with different control conditions - for example, how does video-game based exercise compare with low tech outdoors exercise?

'In summary, exercise videogaming appears to have potential efficacy as a physical activity intervention,' the researchers concluded.
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Rhodes, R., Warburton, D., & Bredin, S. (2009). Predicting the effect of interactive video bikes on exercise adherence: An efficacy trial Psychology, Health & Medicine, 14 (6), 631-640 DOI: 10.1080/13548500903281088

Extras

Eye-catching studies that didn't make the final cut:

Psychologists who study babies need to consider whether their little participants are weighed down with too much clothing or equipment.

The executive secretarial task - an ecologically valid test of executive function.

Theory of mind, or being able to think about other people's mental states, continues to improve between late adolescence and adulthood.

Children raised bilingual show superior conversational awareness and understanding.

Hypnosis as a research method.

A light touch from a doctor on the arm of a patient improves adherence to drug treatment.

Fathers, like mothers, show a bias for holding babies on their left-hand side.

People's Facebook profiles reflect their actual personality, not an idealised version of it.

BPS Research Digest reaches awards finals

I'm delighted to report that the BPS Research Digest has reached the finals of the Research Blogging Awards, in the categories of Best Psychology Blog and Best Research Twitterer. Thanks so much for all your nominations. Fingers crossed for March when the overall winners will be announced.

When doubt about doubt leads to confidence

Can confidence ever be a bad thing? What if it happens to be confidence in your own self-doubt? In a pair of mind-bending experiments Aaron Wichman and colleagues show that doubt layered on doubt doesn't lead to more doubt but rather to increased confidence, as the initial self-doubt is undermined. The researchers say their findings have clinical implications - for instance, by turning a belief that one is definitely going to fail into a belief that one might fail, a therapist could help inspire a client to overcome the paralysis of hopelessness.

First off, Wichman's team measured the chronic uncertainty of 37 participants (by testing their agreement with statements like 'When bad things happen I do not know why'). Half these participants also completed a sentence unscrambling task designed to surreptitiously sow doubt. They had to organise jumbled words into sentences and many of the words, like 'uncertainty', pertained to doubt. The other participants performed an almost identical task but without any doubt-related words. After this, the participants read some imaginary scenarios, such as an employee getting a raise, and rated their confidence in the different possible causes of these scenarios. The key finding here was that the doubt-inducing sentence task led usually uncertain participants to be far more confident in their judgments about the imaginary scenarios. Participants appeared to be doubting their own doubts, leading to confidence.

A second study built on these findings, showing that one doubt-inducing task followed by another led to more confident behaviour. Participants first wrote about real-life instances of doubt and then completed a coordination task that required them to shake their head from side to side, as if saying 'no' (past research shows that this instills doubt whereas nodding increases confidence). These double-doubt participants subsequently rated an imaginary character Donald as more confident and certain - the opposite of what you'd expect if the two doubt-inducing procedures had added together to make more doubt. By contrast, participants who wrote about a real-life instance of doubt and then completed a nodding task, subsequently rated Donald as unconfident and uncertain, consistent with the idea that the secondary nodding task had reinforced the doubt sown in the writing task.

'One might speculate that the difference between being certain of one's agonising insecurity and lack of worth and being uncertain of it may mean the difference between suicide and scheduling an appointment for psychological therapy,' the researchers said. 'Sometimes, self-doubt reduction might be achieved by instilling doubt in one's doubt.'
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Wichman, A., Briñol, P., Petty, R., Rucker, D., Tormala, Z., & Weary, G. (2010). Doubting one’s doubt: A formula for confidence? Journal of Experimental Social Psychology, 46 (2), 350-355 DOI: 10.1016/j.jesp.2009.10.012