Newly Discovered

Improving Eye-Witness testimony by undoing false memories

Diana, Princess of Wales

Diana ten years before a certain false memory started spreading.

Do you remember August 31st, 15 years ago? Diana, Princess of Wales, died in a car crash in Paris along with her partner Dodi Fayed and others. Do you remember seeing the video of the crash? If so, you share that memory with 44% of the participants James Ost and colleagues recruited in 2002 in Britain.

This memory is false.
There is no such video. False memories are not a fringe problem, they are more widespread than one likes to think. Less than three months after the 9/11 attacks in 2001 in New York then US president George W. Bush claimed to have seen the first plane hit one of the Twin Towers. Afterwards, he claimed, he had entered a class room and had eventually been told about the second plane.
And I was sitting outside the classroom waiting to go in, and I saw an airplane hit the tower—the TV was obviously on, and I use[d] to fly myself, and I said, ‘There’s one terrible pilot.’
George W. Bush as quoted in Greenberg, 2004, p. 363
TV channels are usually not very good in predicting terrorist attacks and September 11th was no exception. The first plane hitting the World Trade Center was not shown on live television. The person who was preparing for war as a response to the attacks apparently had a false memory of them.
Marvin Anderson

Marvin Anderson was found guilty of rape due to a false memory. He spent 15 years in prison. Read his story: here.

If these examples are a chilling reminder of just how bad human memory is, consider that in 72% of wrongful convictions – which are later overturned by DNA evidence – eyewitness misidentification was a factor (Innocence Project). The unreliability of eye-witness memory is a widespread problem. New research coming out of Germany and Britain by Aileen Oeberst and Hartmut Blank (article in press) offers a way of overcoming false memories.
Their participants were shown a film of a car chase and heard a short summary of the action. The summary changed two small details but was otherwise correct. When asked in a subsequent questionnaire about the film these changed details were more likely to be misrembered than unchanged details which the summary of the film correctly represented. This finding is called the misinformation effect – a false memory is created through information received after a piece of information has been memorised. This is likely what happened to George W. Bush: the first plane hitting the World Trade Center was indeed shown on TV but only much later. A later viewing changed his memory of an earlier event.
After completing the questionnaire participants were told about the true purpose of the experiment, that details were changed between film and summary, and that they should fill in the questionnaire again. Now, the misinformation effect could no longer be found. Further experiments suggest that people no longer tried to remember a single detail (‘What happened to the car?’) but instead engaged in a more elaborate task of retrieving one or two memories from different sources (‘What happened to the car in the film rather than the summary?’).
Still, usually memories need to be retained for longer than 15 minutes. How do the findings change with a five week gap between implanting the false memory and trying to abolish it? The misinformation effect could still be reduced simply by telling people five weeks after getting film and summary that the two did not entirely match. Introducing a more elaborate questionnaire further improved memory. It leads to better performance because people are told in detail which manipulated details to consider carefully and it asks where they have a piece of information from.
The authors hesitantly suggest these changes to eye-witness testimony: 1) remind them that ‘they might have encountered additional information relevant to a witnessed event from various post-event sources (e.g. other witnesses, the media, etc.) and that some of this information may have been inconsistent with their own perceptions and memories.’ 2) ‘ask people not only for event details but also for (possibly contradictory) post-event information, and also […] explicitly ask for the source of every remembered detail.’ By making the remembering process more elaborate than a simple ‘Tell me what you know’ one can help people remember correctly.
The implications for what we mean by ‘memory’ are intriguing. Depending on what task you set people, they remember things differently. Apparently, constructing a memory from bits and pieces scattered in the mind is highly dependent on the situation we are in. The reason why we are not aware of this is because the brain plays a trick on us: a memory always feels somehow real, genuine, and personal. Even that of Diana’s crash video.
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Greenberg, D.L. (2004). President Bush’s False ‘Flashbulb’ Memory of 9/11/01 Applied Cognitive Psychology, 18, 363-370 DOI: 10.1002/acp.1016

Oeberst, A., & Blank, H. (2012). Undoing suggestive influence on memory: The reversibility of the eyewitness misinformation effect Cognition DOI: 10.1016/j.cognition.2012.07.009

Ost, J., Vrij, A., Costall, A., & Bull, R. (2002). Crashing Memories and Reality Monitoring: Distinguishing between Perceptions, Imaginations and ‘False Memories’ Applied Cognitive Psychology, 16, 125-134 DOI: 10.1002/acp.779

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Images:

1) By Rick (Princess Diana, Bristol 1987) [CC-BY-2.0 (http://creativecommons.org/licenses/by/2.0)%5D, via Wikimedia Commons

2) via Innocence Project: http://www.innocenceproject.org/Content/Marvin_Anderson.php

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Mimicking infants rather than adults – how infants choose their models.

The infant academy by Joshua Reynolds

The infant academy by Joshua Reynolds

Parents are often afraid of what happens once their children hit puberty and stop emulating their parents. Recent research suggests that this fear should start a lot earlier: in infancy. Of course, infants need their parents to learn but they need other infants when it comes to imitating things they already know.

Two recent articles by Zmyj from the Ruhr university in Bochum and colleagues present convincing evidence to back up infants’ occasional preference for peer imitation. First, when presented with videos of people playing with novel toys in familiar ways, fourteen month olds imitate a peer more than an older child aged 3.5 or an adult. Secondly, when presented with similar videos of people performing simple gestures (banging on the table, waving, clapping…) they again imitated a 14 month old more often than an older child or an adult.
These results are curious because at this age infants typically spend more time with their parents than with other infants. Furthermore, as far as imitation is used to learn new things the infants should prefer adults who are more knowledgeable. When it comes to novel actions the learning objective does actually prevail. Switching on a new lamp with the head or building a rattle is more likely to be copied from an adult model rather than an infant model (Seehagen & Herbert, 2011; Zmyj, Daum et al., 2012).
When it comes to infant-infant imitation, it may come out of a desire to belong to the same social group as the model, a sort of precursor to facebook’s Like button. Infant-adult imitation, on the other hand, may be more like a student-teacher relationship.
This set of studies powerfully shows that age matters to infants. They copy the behaviour of others depending on how old the model is and what sort of behaviour is shown. This sort of reasoning was long thought to be beyond 1 ½ year olds. Recent evidence, however, shows that infants play a more active part in choosing who to emulate than you may think.
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Seehagen, S.,, & Herbert, J.S. (2011). Infant Imitation From Televised Peer and Adult Models Infancy, 16 (2), 113-136 DOI: 10.1111/j.1532-7078.2010.00045.x

Zmyj, N., Aschersleben, G., Prinz, W., & Daum, M. (2012). The Peer Model Advantage in Infants’ Imitation of Familiar Gestures Performed by Differently Aged Models. Frontiers in psychology, 3 PMID: 22833732

Zmyj, N., Daum, M.M.,, Prinz, W.,, Nielsen, M.,, & Aschersleben, G. (2012). Fourteen-month-olds’ imitation of differently aged models Infant and Child Developement, 21 (3), 250-266 DOI: 10.1002/icd.750

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image: By Joshua Reynolds (jundurrahman.files.wordpress.com) [Public domain], via Wikimedia Commons
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Infants choose their teachers

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Is it safe to talk while driving? – Partly depends on what you talk about.

World Health Organization reports about road safety are mind boggling: about 1.2 million people die on the world’s roads every year. For people of my age (15 to 29 year olds) it is the leading cause of death.

A rather recent addition to laws designed to reduce these numbers was the adoption of compulsory hands-free devices for mobile phones. Their safety value is easy to understand. When you look at a mobile phone display you cannot simultaneously look at the road. Similarly, using your hands for typing and using them for steering are at least partly incompatible actions.
mobile phone use while driving

How mobile phone use impairs sight and hands.

From a psychological point of view the current law tries to ensure that visual input channels (eyes) and motor output channels (hands) remain undisturbed. But what about the brain areas which control these channels?
This is the question recently investigated by Bergen from UC San Diego and colleagues. They put undergraduates in a driving simulator giving the impression of a motorway with steady traffic and a car in front of the driver breaking from time to time. Simultaneously, the driver had to judge simple true/false statements from the motor domain (e.g., “To open a jar, you turn the lid counterclockwise.”), the visual domain (e.g., “The letters on a stop sign are white.”), or the abstract domain (e.g., “The capital of North Dakota is Bismarck.”). As a baseline condition, people were just asked to say “true” or “false” several times.
Why choose such questions? There is both behavioural and brain-imaging evidence that language comprehension involves the simulation of what was said. This set of findings is often summarised as embodied cognition and its take-home message is something like this: in order to understand it, you mentally do it. For example, to answer a motor question, you use your brain areas doing motor control and make them simulate what it would be like to open a jar. Based on the outcome of this simulation you answer the question.
So, will visual or motor questions affect driving differently than abstract questions because the former engage the same brain areas as those needed for driving while the latter don’t? The alternative would be that asking anything distracts because general attention gets pulled away from driving.
The results go both ways. First, one measure was affected by the true/false statements but not by which kinds: quickly breaking when the car in front breaks. The time it took to do so was longer if any sort of question was asked compared to baseline. This suggests that domain general mechanisms were interfered with through language, e.g., attention.
Liza minelli driving

Was she a safe driver? May depend on whether she talked and if so about what.

Second, one measure was affected by what kind of statements had to be judged:generally holding a safe distance to other cars. This distance was greater if visual questions were asked compared to abstract questions and compared to baseline. A similar, albeit not as clear, pattern emerged for motor questions. It looks as if participants were so distracted by these kinds of questions that they fell behind their optimal driving distance. This suggests that a task such as keeping a safe driving distance which requires visual working memory (compare ideal distance to actual distance) and corrective motor responses (bring ideal and actual distances closer together) is influenced by language comprehension through mental simulation.
On the one hand, the scientific implications are quite straight forward. Bergen and colleague’s results suggest that those low level perception and action control areas which are needed for quick reactions are not what embodied cognition is about. Instead it seems like embodied cognition happens in higher perceptual and motor planning areas. Furthermore, the whole embodied cognition idea gets quite a boost from a conceptual replication under relatively realistic conditions.
On the other hand, the practical implications are somewhat controversial. Because talking in general impairs quick reactions by the driver, even hands-free devices pose a risk. This danger is compounded by talking about abstract topics since the driving distance is reduced compared to visual topics.
The authors refrain from saying that any sort of conversation should be prohibited. Passengers share perceptual experiences with the driver and can adjust their conversations to the dangerousness of the situation. Mobile phone contacts can’t do this. But what if you want to be really really safe? Well, cut your own risk of dying and take public transport. There you can chat and cut your death risk by 90% (bus) or even 95% (train or flight) compared to car travel (EU numbers).
London bus

A safe way to travel.

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Bergen, B., Medeiros-Ward, N., Wheeler, K., Drews, F., & Strayer, D. (2012). The Crosstalk Hypothesis: Why Language Interferes With Driving. Journal of experimental psychology. General PMID: 22612769

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images:

1) By Ed Brown as Edbrown05 (Own work) [CC-BY-SA-2.5 (www.creativecommons.org/licenses/by-sa/2.5)], via Wikimedia Commons

2) By Alan Light (Flickr) [CC-BY-2.0 (http://creativecommons.org/licenses/by/2.0)%5D, via Wikimedia Commons

3) By Original author was User:Kameragrl at Wikitravel Shared, transferred to Commons by User:Oxyman (http://wikitravel.org/shared/Image:London_Bus.jpg) [CC-BY-SA-1.0 (http://creativecommons.org/licenses/by-sa/1.0)%5D, via Wikimedia Commons

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Psychological principles as guidelines for effective PowerPoint presentations

A presentation using Powerpoint. Corporate pre...

How good can it get?

You probably wouldn’t have much difficulty if I asked you to imagine a bad PowerPoint presentation. Nowadays one sits through so many of them that confusing, boring or annoying slide shows are sometimes perceived as the norm rather than the exception. A research team from the universities of Stanford, Amsterdam and Harvard headed by Stephen Kosslyn explains how to do it better. In order to reap off the benefits and avoid the pitfalls of visual aids, presenters should think about avoiding weaknesses of human information processing and play on the strengths of such processing.

 
Kosslyn and colleagues see the task of the audience viewing a PowerPoint presentation as composed of three steps: a) information needs to be acquired, b) information needs to be processed, c) information needs to be connected to knowledge. They derive eight principles that a presenter should follow based on this analysis.
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a) encoding, i.e. acquiring information and turning it into a usable form
1) Discriminability: make it easy for the audience to discriminate colours, letters, sizes, line orientations etc.
2) Perceptual Organisation: group things effectively in the visual space you’ve got
3) Salience: use large perceptual differences to guide attention to what is IMPORTANT
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b) working memory: holding information in mind in order to integrate it online
4) Limited Capacity: understanding breaks down once too much information has to be retained
5) Informative Change: when something perceptual changes, this change has to mean something
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c) accessing long term memory: connect the new information with knowledge in order to extract meaning.
6) Appropriate Knowledge: avoid as much novel concepts, jargon or symbols as possible
7) Compatibility: the meaning of a message needs to be compatible with its form
8) Relevance: provide neither too much nor too little information
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These principles may look very obvious but they are frequently violated. From an internet sample of slide shows it became clear that on average a PowerPoint presentation violates six principles at least once. Some principles were nearly always ignored: 1) discriminability, 4) limited capacity, 5) informative change.
Now, one may argue that these principles are simply guidelines that lay people are unaware of. No wonder they get violated. However, in a subsequent laboratory experiment participants were 80% correct in choosing a non-violating slide and rejecting a bad one. Moreover, when asked to say why one slide was better, more than 80% of the correct choices were appropriately justified.
So, this study is about what one already knows but still ignores when designing a slide show. The authors use a backdrop of psychological literature to predict what sorts of principles should guide PowerPoint presentations. What they, unfortunately, fail to do is to empirically test each principle’s impact on presentation understanding and memory. As such, this study simply presents a set of guidelines, says that presentations usually violate guidelines and that most people are aware of these violations. How important the guidelines are to begin with remains unclear.
The main take-home message is that the more work a presenter does for his/her audience, the more the audience can tune into the content of the presentation. For my part I am always guided by a more memorable principle:
Look around the room and search for the newbie or the bored one or the least intelligent listener. S/he is your target audience.
For a complete list of useful rules which may help you and especially your audience, see the appendix of Kosslyn and colleagues’ paper.
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Kosslyn S.M., Kievit R.A., Russell A.G., & Shephard J.M. (2012). PowerPoint® Presentation Flaws and Failures: A Psychological Analysis Front. Psychology, 3 DOI: 10.3389/fpsyg.2012.00230

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Images:

1) Photo credit: Wikipedia

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Why do we like sad Music?


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But I’m a creep.
I’m a weirdo.
What the hell am I doing here?
I don’t belong here.

 

Why would anyone want to listen to this?

Radiohead’s song Creep is not the exception in being a heartbreaking but nonetheless successful song. According to Wikipedia , of the ten best-selling music singles ever several are clearly sad songs: Elton John’s Candle in the Wind, The Ink Spot’s If I didn’t care, or Kenny Roger’s Lady. Music does influence one’s mood. For that reason some psychological experiments even use it as a mood induction technique. But given that people generally strive for happiness, why would anyone willingly opt for sad music?

This is exactly what Van den Tol and Edwards asked people online (article in press at Psychology of Music). The most important function they identified in the responses was (re-)experiencing affect, i.e. listening to sad music in order to induce ‘sadness, loss or grief, and occasionally other negative feelings such as disappointment and anger’ (p. 10). Other functions were also mentioned but the take-home message is that, usually, sad music is chosen because it makes people – who are often already sad – feel sad. Very puzzling.

Even more puzzling is that these objectively negative feelings were only rarely reported as being experienced in a negative way. As if music-induced sadness is not quite like real sadness. Van den Tol and Edwards interpret their results as sad music being a sort of self-regulation tool. But how does the tool work?

No one really knows. Still, there are some ideas out there.

1) The safe distance theory

Thompson (2009; see Schubert, 1996) claims that musical sadness is unlike real sadness because, well, it isn’t actually real. It is without consequence. Therefore, one can explore a feeling without becoming engulfed in it. According to this hypothesis one can listen to Radiohead’s Creep and feel like a complete loser without actually having to be one.

It is difficult to test this because one would have to distinguish between participants’ safely distant sadness and their real sadness. I doubt that any ethical board would allow a researcher to deliberately sadden a participant for real.

2) The shared pain theory

Levitin (2008) claims that musical sadness serves to ‘[bring] us through stages of feeling understood, feeling less alone in the world, hopeful that if someone else recovered so will we’ (p. 135). Like in most of his book, Levitin sees music as a social tool. On this account, the difference between musical sadness and real sadness lies in the former one being shared while the latter one is more private. Elton John’s Candle in the Wind is a good example. Released following Lady Diana’s death, it perhaps helped people worldwide to share an emotion which they otherwise would have had to deal with by themselves.

3) The Prolactin theory

Prolactin is a hormone associated with feelings of tranquillity, calmness, well-being, or consolation. Huron (2011) suggests that the body uses it to counteract grief and thus avoid descending into an uncontrollably depressive episode. Such hormonal counter-measures to negative environmental inputs are also found for physical pain. Physical pain is reduced by endorphins. Such a bodily mechanism can be exploited – as when heroin addicts fool the brain’s response to pain. Huron (2011) proposes that sad music can activate the counter-measures to actual sadness – i.e. prolactin production – without any real sadness being present. One gets the hormone’s consoling effect without the sadness and might thus actually enjoy it.

On should not forget that -even though it is intuitive – Huron’s Prolactin theory is not supported by a great deal of experimental evidence. But at least it is straight forward to test.

Of course, all three theories could be true. The puzzle of people’s tendency to often listen to sad music could have to do with the safe distance between musically induced sadness and one’s true emotions. This distance may allow prolactin to have an unusually positive effect because it is not balanced by the real sadness it is designed to counteract. On top of that, a more cognitive appreciation of sharing this experience with other people may aid the process. Targeted research is needed in order to test these theories.

So, people do indeed strive for happiness and therefore enjoy energetic, upbeat music. However, when times get rough it can seem better to switch gears and deal with the sadness first before moving on. It appears like this is where sad music could come in. According to the three aforementioned theories, gloomy music not so much leads to bad moods. It is the other way around. Bad moods require sad music.

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Huron, D. (2011). Why is sad music pleasurable? A possible role for prolactin. Musica Scientiae, 15, 146-158. doi: 10.1177/1029864911401171

Levitin, D.J. (2008). The World in Six Songs. London: Aurum Press

Thompson, W.T. (2009). Music, Thought, and Feeling: Understanding the Psychology of Music. Oxford: Oxford University Press

Van den Tol, A.J.M., Edwards, J. (in press). Exploring the rationale for choosing to listen to sad music when feeling sad. Psychology of Music. doi: 10.1177/0305735611430433

Infants choose their teachers

By Hardeep Singh from Vancouver, Canada (Mohkam Mopping) [CC-BY-2.0 (www.creativecommons.org/licenses/by/2.0)], via Wikimedia Commons
My father has seen his four children grow up and is still fascinated with the things that children do NOT know. He likens them to a new computer whose hard drive is still void of information and needs to be filled by a user, i.e. by their parents or other care takers. The computer metaphor is a very widely used one in the cognitive sciences. It turns out that for infant learning it is a misleading one. Rather than being like an empty disc which accumulates knowledge, infants act like explorers who use every bit of information they have in order to make sense of the unknown, to evaluate new inputs and ultimately to decide for themselves what to learn.
Zmyj and colleagues have an article in press in the journal Infant and Child Development which illustrates this nicely. 14 month old infants were presented with a new object: a lamp. Ordinarily lamps are switched on with hands (you knew that, right?) but infants were shown videos in which another person switches the lamp on using the head. Will children imitate them and, thus, show evidence for learning in terms of how to use a new object? They will, but it depends on how old the person in the video is. Most infants imitated an adult, less infants imitated a child aged three and a half, even less imitated another infant. This pattern of results makes intuitive sense. Instead of imitating any person blindly, infants trust people more who tend to be more knowledgeable given that they are older.
Previously, Seehagen and Herbert (2011) had found similar results for infants asked to imitate a person building a rattle. However, Zmyj and colleages went further and showed that a different pattern emerges when children see a person use toys in a rather intuitive way. Now, the infant peer was imitated most and the older child or the adult less. Infants appear to imitate people differently depending on whether they want to acquire knowledge (adults have more knowledge than infants) or whether they want to have fun (infants know better how to have fun than adults). Even before their second birthday, children decide for themselves who they turn to for learning.
Infants deciding what to learn? At 14 months they can hardly speak. They just started walking. Toilet training is still an issue. And they should decide for themselves? The aforementioned studies could perhaps be reinterpreted in a less extreme way. Perhaps appearances drive the effect. By 14 months the child could find an adult more like parents and, thus, trust an adult more for learning novel things. It is imaginable that the child identified better with fellow infants when there is nothing to learn and, thus, imitates them more. This argument is not only a bit constructed, it is also contradicted by a bunch of publications contrasting two adults rather than an adult and an infant.
Chow and colleagues presented infants with either an adult who is reliable or an adult who is not. The unreliable adult would express great happiness when looking into a container even though the container is empty. Children may find such an adult a bit odd. His actions do not really match expectations. Chow and colleagues (2008) found infants to be more hesitant in exploring a container which an unreliable informant claimed contained a nice object. They followed a reliable adult’s information faster. The same or a similar manipulation of an adult’s reliability also changes other infant behaviours:
– their looks behind a barrier to see what the adult is going on about (Chow et al., 2008)
– their surprise at seeing the adult look in the wrong direction in order to find an object (Poulin-Dubois and Chow, 2009)
– their imitation of the head movement to switch on the aforementioned new lamp (Poulin-Dubois et al., 2011; Zmyj et al., 2010).
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Infants are not like a container which you can fill with knowledge. The computer metaphor of an empty hard drive simply does not hold. Every new bit of information is evaluated in terms of where it comes from. This evaluation itself is driven by what the infant already knows. It is as if children try to coat themselves against unreliable information. Before toddlers have seen their second birthday cake they show a higher level of self-guided learning than parents realise. You better don’t act unreliable in front of them!
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Chow, V., Poulin-Dubois, D., & Lewis, J. (2008). To see or not to see: infants prefer to follow the gaze of a reliable looker. Developmental Science, 11, 761-770. doi: 10.1111/j.1467-7687.2008.00726.x
Poulin-Dubois, D., & Chow, V. (2009). The Effect of a Looker’s Past Reliability on Infants’ Reasoning About Beliefs. Developmental Psychology, 45, 1576-1582. doi: 10.1037/a0016715
Poulin-Dubois, D., Brooker, I., & Polonia, A. (2011). Infants prefer to imitate a reliable person. Infant Behavior and Development, 34, 303-309. doi:10.1016/j.infbeh.2011.01.006
Seehagen, S., & Herbert, J.S. (2011). Infant Imitation From Televised Peer and AdultModels. Infancy, 16, 113-136. doi: 10.1111/j.1532-7078.2010.00045.x
Zmyj, N., Buttelmann, D., Carpenter, M., & Daum, M.M. (2010). The reliability of a model influences 14-moth-olds’ imitation. Journal of Experimental Child Psychology, 106, 208-220. doi:10.1016/j.jecp.2010.03.002
Zmyj, N., Daum, M.M., Prinz, W., Nielsen, M., & Aschersleben, G. (in press). Fourteen-month-olds’ imitation of differently aged models. Infant and Child Development. doi: 10.1002/icd.750

Invisible Distractions: Men get worse when expecting unknown female experimenter

Flirting is exhausting. It requires you to control your behaviour (‘Don’t act like a moron!’), monitor the impression you are making (‘Are we laughing at the joke or at me?’) and communicate on several different layers (‘Do you want to come up for tea?’). No wonder men’s cognitive performance is worse afterwards. Surprisingly though, the exhaustion sets in a lot earlier already: before men even know who the woman may be.
Nauts and colleagues have a (freely available) article in press at the moment which looks at the cognitive performance of men and women as a result of being observed by an unknown male of female experimenter. In a first experiment, they asked participants to read words out loud while either ostensibly being monitored by ‘Bas’ (a fake male experimenter) or ‘Lisa’ (a fake female experimenter). Importantly, participants only knew the names of their observers. They never saw them or directly interacted with them. It must have looked like your typical unsexy psychology experiment in which boredom is the unmeasured main effect.
Before and after reading words out loud, people performed a Stroop task. Basically, it asks you to name the ink colour of coloured colour words, e.g. people are quite fast on RED, GREEN, and BLUE but usually slower on RED, GREEN, and BLUE. This difference is sometimes taken as an indicator of people’s ability to overcome an easy, fast response due to attention on the word meaning. As predicted, men’s Stroop performance was significantly worse after having been ‘observed’ by ‘Lisa’ compared to ‘Bas’, i.e. their cognitive performance on a standard control task was worse just because they felt that a completely unknown woman (they would likely never meet) had a look at their mouth while pronouncing words.
In a follow-up experiment participants were told about the upcoming word reading task – and the gender of the experimenter who would observe them – already before the Stroop task was performed for the first time. As predicted, men’s Stroop performance was somewhat worse when merely expecting to be observed by an unknown female experimenter compared to a male one [1]. This suggests that the preparation for being observed by a woman is enough to cognitively exhaust men.
Interestingly, in neither experiment women’s cognitive performance was affected by the gender of the previous (Experiment 1) or upcoming (Experiment 2) observer. Mind that the statistical power was greater for women given that more were tested. In other words, the experiment was more likely to find a female participant effect than a male participant effect. The authors suggest that women are generally more selective in terms of seeing a situation as flirtatious or not. Men on the other hand, well, are less selective.
So, the exhaustion of flirting appears to start even before the flirt, or even before a situation which could possibly lead at some point to a flirt. While the authors are right in writing that a replication with homosexual participants would be interesting, the far more obvious short coming lies elsewhere.
Nauts et al. did not just test ‘men’ and ‘women’ but 21 year old students. To put it more bluntly, they arguably recruited the most horny people on campus. So, this study is not just an example of young men’s readiness to expand cognitive resources on a completely unlikely mating partner. It is also an example of the need for Psychology to go beyond student samples in order to truly reveal something about human nature.
Nauts, S., Metzmacher, M., Verwijmeren, T., Rommeswinkel, V., & Karremans, J. (in press). The Mere Anticipation of an Interaction with a Woman Can Impair Men’s Cognitive Performance . Archives of Sexual Behavior. doi: 10.1007/s10508-011-9860-z
LINK
[1] A  one tailed test with a p-value of p=.04 should be taken with a pinch of salt.