Wednesday, 6 July 2011

Why is a touch on the arm so persuasive?

A gentle touch on the arm can be surprisingly persuasive. Consider these research findings. Library users who are touched while registering, rate the library and its personnel more favourably than the non-touched; diners are more satisfied and give larger tips when waiting staff touch them casually; people touched by a stranger are more willing to perform a mundane favour; and women touched by a man on the arm are more willing to share their phone number or agree to a dance. Why should this be? Up until now research in this area has been exclusively behavioural: these effects have been observed, but we don't really know why. Now a study has made a start at understanding the neuroscience of how touch exerts its psychological effects.

Annett Schirmer and her colleagues used EEG to record the surface electrical activity of the brains of dozens of female participants who were tasked with looking at neutral or negative pictures (e.g. a basket or a gun to the head). Before each picture appeared, the participants were sometimes touched on the arm by a female friend; touched by a mechanical device (a pressure cuff); or they received no touch. The idea was to see whether and how being touched changed the way the brain responded to emotional and neutral pictures.

A further detail is that the mechanical touch was described as either under the friend's control, with the friend located elsewhere, or under computer control. This was to see if physical proximity matters and whether it matters who does the touching. For comparison, a final experiment also tested the effect of an auditory tone, which preceded some pictures but not others.

The most important finding is that a touch on the arm enhanced the brain's response to emotional pictures, as revealed by the size of what's known as the late positive component (LPC) of electrical brain activity. The LPC is thought to be associated with evaluative mental processes and a touch led to a greater LPC for emotional pictures compared with neutral ones.

Touch had this effect regardless of how it was administered and who did the administering (friend or machine). This suggests the reported effects of touch are largely "bottom up" - that is, based mainly on the incoming stimulation - rather than "top down", to do with beliefs about the meaning of the touch. Unlike touch, the auditory tone didn't increase the brain's sensitivity to emotional pictures.

"Emotional information presented concurrently with touch may be more motivating such that more processing resources are allocated to them than to emotional information presented without touch," the researchers said.

One consequence of this, Schirmer's team speculated, could be that the touched person is primed to be more altruistic, consistent with previous behavioural results. "Based on the present findings," they explained, "we propose that such behaviour occurs because the tactile signal alerts its recipient and enhances the processing of concurrent events, particularly if they are emotional. Such enhanced processing may then, among others, boost empathy and increase the likelihood that the touch recipient acts in favour of the toucher."

ResearchBlogging.orgSchirmer, A., Teh, K., Wang, S., Vijayakumar, R., Ching, A., Nithianantham, D., Escoffier, N., and Cheok, A. (2011). Squeeze me, but don't tease me: Human and mechanical touch enhance visual attention and emotion discrimination. Social Neuroscience, 6 (3), 219-230 DOI: 10.1080/17470919.2010.507958



skybluskyblue said...

I wonder how a person on the autism spectrum would respond. Personally, it is too much for me to take and would be very distracting.

Christian Jarrett said...

good question!

Anonymous said...

I would find deliberate touching by a member of staff I was dealing with just plain rude, and very intrusive. I would be making a formal complaint if I thought it was organisational policy! For what it's worth, I am on the autism spectrum, but not sure how much that affects my reaction here.

Anonymous said...

would be to scared to touch a stranger encased they felt i wad harassing them. its the world we live in.

Mark O'Sullivan said...

I can't help feeling that this is an excellent example of how American research can lead to misleading conclusions about more inhibited cultures, such as those of Northern Europe.

Anonymous said...

I am also on the autism spectrum. If a uniformed stranger touched me on the arm, I would assume I was in severe trouble for violating a rule and about to be punished.

Anonymous said...

The research doesn't seem to be just in relation to customers and employees, it seems that they were using those as examples most readers are familiar with. Another of the examples was in relation to asking someone to dance, so I think there has been too much focus on businesses in the responses.
Personally however, I do find that I favour restaurants with staff that do touch, formally (a hand-shake) or informally (a light pat on the back/arm).
This article does seem to fit into a variety of cultures, rather than just in the U.S.; in Eastern European countries, such as Turkey and Italy, favour a more friendly approach to customers as well as peers and guests. If you are however looking for a more local example, look to your own homes. Touching is a very common occurrence between partners, friends and family members. Perhaps this use of touching strangers acts to make both persons more comfortable in each others company, hence the "recipient acts in favour of the toucher."

McButterfly said...

I touched someone on the shoulder when she was unnecessarily upset with me and she reacted fairly violently. So, I don't agree with this at all in my experience.

If someone I didn't know well touched me, I would probably react negatively and feel that the person was taking advantage in some way and was trying to manipulate me. Which is exactly what people would use this information for.

Anonymous said...

So what's the science behind being called "Hon, Sugar, and Baby" by the waitress. Seems to be just as effective.

Anonymous said...

They said ARM people .... there is nothing harrassing about that. That's the problem with an uptight view.

John Bosley said...

This sort of phenomenon is well known ot clinical hypnotists and NLP practitioners. They often use it to "anchor" a suggestion.

Victor said...

Touching could help impoving the interaction and building rapport (depending on the situation).
The perception of the interaction changes (subconsciously). It seems more fiendly and intimate. But only if the receiver responds well to the touching.

I think most people, who say they don't like to be touched, would respond well when it's performed in a natural and subtle manner.

Hayley Burgess said...

Hey! It's not an uptight view - it's called 'personal space' for a reason.

I used to have a manager who deliberately entailed the 'kind touch' strategy as a means of manipulation, predominately with the female employees. Everyone knew it, everyone talked about it, and everyone resented it. EVERYONE. Some people (including me) actively avoided him for this sole reason.

Bearing in mind that a swinger was included in my ergonomic sample, I'd say it's not about being uptight, but once one's attention is drawn to the act, how we retrospectively assess how welcome the touch was. If it's an attractive frenchman, maybe that's ok. If it's your unattractive manager... Well, maybe not.

Anonymous said...

Perhaps the intent of the "toucher" enters into the picture in some cases. When I touch folks who are not previously known to me, the gesture is part of an exchange which includes a genuine appreciation of the person. Sometimes compassion is involved, sometimes I sense an intense weariness on their part (i.e., a grocery checker) and hope it is possible to share a bit of energy through touch. But I don't linger, allowing them to think I expect something. Perhaps it means more to me than to the recipient, but so far I haven't encountered any offense. I must share though that one time, after I smiled at a frequently viewed homeless woman, she glared at me, saying "What you lookin' at me for?" and reached into her backpack to pull out a hatchet. I looked away and retreated. However, our own instincts can be a valuable guide most often.

Emily said...

For the average person, touching seems fine. I've used it to flirt, to convince, and to just make people feel welcome. Clearly you are doing something else to anger, confuse, or upset the person if you have a bad experience with just touching their arm or shoulder.

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