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Virtual Race Manipulation

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In the article “When Prejudice does not pay: Effects of Interracial Contact on Executive Functioning”, Richeson and Shelton found that people who score high on an implicit racial bias test, show the highest impairment on executive functioning, after interaction with a black experimenter. They state that this effect occurs when a member of the majority-group has to interact with a member of a minority-group. The now (at least in Nijmegen) famous bushalte-experiment by Daniel Wigboldus did show different approach tendencies for Caucasian versus Moroccan virtual confederate, whereas the Caucasian virtual person is considered belonging to the majority group and the Moroccan person is considered belonging to the minority group.

I am wondering in how far self-consciousness is involved in these approach tendencies and if the effect disappears if the group inclusion of the participant matches those of the (virtual) confederate. There have been researchers (mainly in the US) who have taken on the role of an African American, by changing their appearance, but so far, to my knowledge, no practical experimental manipulation of race has been suggested. I propose to do just that in a virtual lab experiment.

In a study called Video Ergo Sum: Manipulating Bodily Self-Consciousness (Lenggenhager, 2007) participants where placed in a virtual reality that projected their own body in front of them. In what seems an elaboration of the rubber hand effect, those participants began experiencing this body as their own. I believe that it would be technically easy to adjust the skin tone of this avatar, and thus manipulate race temporarily. To investigate whether ingroup/outgroup really is an important factor in racial bias I propose the following procedure, to be used with Caucasian participants:

Initially all participants complete a racial IAT. They are then randomly assigned to either the same-race or the different-race condition and they enter the virtual reality. There an avatar (of themselves), which is in sync with their body movements, will be projected in front of them. In the same-race condition they will appear as a Moroccan person, in the different-race condition they will appear as Caucasian. They then will have to approach a Moroccan avatar (as has been done in the previous bushalte-experiments). I hypothesise that if the (virtual) participant’s race is temporarily changed to match the race of the (virtual) confederate (Moroccan) the effect of the approach tendency will decrease. This would suggest that self-consciousness of race does play a role in interracial interaction.

Differences in Impulsive Processes

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Imagine walking into a library. All objects in that building are based on the same principle, they all use paper with letters printed on it to deliver a specific message. So should we just put all the books, articles and newspapers on one pile? No – it makes sense to structure the objects according to the topic they deal with (so that books and newspapers about gardening stand close to each other). This additional information helps us to deal with the information presented in a much more efficient way. The same is true for the categorization of automatic processes into meaningful groups.

The model of Strack and Deutsch proposes different levels of the reflective system, like propositional categorization or Noetic decision. The Impulsive system is composed of episodic and semantic links, which they call the “associative store”. It is within this associative store that through perception certain concepts are activated and activation spreads to behaviour schemata, that in turn may be acted upon. These impulsive actions are important, because only they can produce behaviour.

A scientific model is always a simplification of reality. Models that can explain everything are indeed worthless to science. The question then becomes: What is the ultimate goal of our research into behaviour? Do we want to end up with a system that explains behaviour in purely mechanical (biological, chemical, and physical) terms, as sometimes suggested by neuroscience? If that is the case, then we should try to incorporate all automatic effects into one big theory. Yet within such a model it would be hard to generate specific hypotheses to investigate. Taking a smaller concept (such as goals) it is much easier to identify specific automatic behaviour that is connected to it (such as goal activation). The description of the automatic process at hand can therefore be optimized to the specific situation (for example how different goals might interact), which makes it easier to focus on the relevant facts. The hypothesis as proposed by the duality model of Deutsch and Strack can be tested on the theories about automatic effects. Incorporating new knowledge about the processes within the impulsive system can improve those theories, but does not mean we have to take everything into account at the same time.

Written by Martin Metzmacher

February 21, 2008 at 8:33 am

Chicken or Egg – Smoking and Stress/Negative Affect

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In terms of psychopharmacology, nicotine acts directly on nicotine cholinergic receptors, which are located in part on mesolimbic dopamine neurons. By stimulating the nicotine receptor, dopamine is released from the mesolimbic neurons, accompanied by a sense of reward and pleasure. Whereas other drugs, such as cocaine, that act on the same neurons, block the dopamine transporters, nicotine shuts down the nicotine receptor shortly after binding to it, thus the sensation of pleasure comes in small boosts. This is the reason why smoking a cigarette is desirable, but does not influence behaviour strongly. Effects are the elevation of mood, enhancement of cognition and decrease of appetite. However, it was found that smoking does not attenuate negative affect more than drinking a glass of water does.

Due to the specific biological effects of smoking (sending short bursts of pleasure to the mesolimbic dopamine neurons) the specific effect of smoking might only be very short. Other processes that stimulate this kind of the brain usually have longer lasting effects, for example eating food or drugs such as cocaine. The question is: Is the duration of an effect an important factor in the strength of the association between the embodied affect and the behaviour? If behaviour is linked to an automatic positive valence that originates from this region in the brain, the embodied cognition might be fooled into thinking that it is engaging in very “reward worthy” behaviour, when it is just getting a short “buzz” from the next puff. The feeling of relaxation might indeed be there, but too short-lived to be detected by the experimental paradigm used. Furthermore this behaviour (drinking or smoking) involves both oral stimulation and the perception of the body (through the smoke or the water running down the stomach), which might be pleasant in itself.

One reason why smoking did not show any effect on negative affect could be that buffering negative affect is closely connected to self-esteem, as suggested (and tested) by Terror Management theory. For many people (also for smokers) smoking has a negative valence. So the positive effects of smoking on negative affect regulation might be canceled out by the negative effects on self-esteem.

The reason why smoking a cigarette is relaxing to smokers might be closely related to the effects of drinking a glass of water – focusing attention on one behaviour. This behaviour is for the most part automatic and does not require cognitive resources. And even though this behaviour is mostly automatic, smoking a cigarette or drinking a glass of water means (at least in the experimental situation) taking a break from what was going on before. Lighting up a cigarette might give smokers the sign to engage in relaxation in real life. This is true especially nowadays as new laws prohibit most people to smoke inside at their workplace.

I believe that smoking can not be explained as a biological problem alone. Conditioning plays an important role, but it does not take into account many other psychological factors that are also important. The connection between smoking and affect regulation is not totally learned by physical conditioning processes within our body, but also by social learning. At least the countless advertisements for cigarettes paint the picture of relaxation and feeling good. Children of smoking parents engage much more in smoking behaviour, than would be expected on the basis of genetic influence. So imitation of behaviour might play a role. There are also other social processes at hand. For example the feeling of belonging to the ingroup of “smokers” in a given social setting might be beneficial. Taking a collective smoking break is also a good chance to engage in casual interaction with someone you do not know so well.

The problem with experimental research on smoking behaviour is that real life settings are hard to control and there are just too many variables, which cannot be controlled for. Laboratory experiments on the other hand often have limited ecological validity. I propose a straight-forward experiment that investigates on the relationship between smoking and stress in the virtual lab. Using the virtual lab has the advantage of supplying every participant with the exact same environment. The scenes used resemble a typical every day transport scenario. One has to move through a virtual train station in order to get to the train in time. The train station is either packed with people (high stress condition) or relatively empty (low stress condition). Arriving at the train platform the participant learns that the train will arrive late and that he will have to wait a few minutes. In that time he either does nothing, smokes a virtual cigarette or smokes a real cigarette. Stress is measured throughout the experiment by galvanic skin response. If the virtual cigarette had the same effect as the real cigarette it would prove that there are important processes at work next to the biological ones.