When it comes to touch, to give is to receive

Date:September 10, 2015

Source:Cell Press

Summary:Have you ever touched someone else and wondered why his or her skin felt so incredibly soft? Well, now researchers present evidence that this experience may often be an illusion.

Have you ever touched someone else and wondered why his or her skin felt so incredibly soft? Well, now researchers reporting in the Cell Press journal Current Biology on September 10 present evidence that this experience may often be an illusion.

In a series of studies led by Aikaterini Fotopoulou of the University College London, participants consistently rated the skin of another person as being softer than their own, whether or not it really was softer. The researchers suggest that this phenomenon may exist to ensure that humans are motivated to build social bonds through touch.

“What is intriguing about the illusion is its specificity,” says Antje Gentsch, also of the University College London. “We found the illusion to be strongest when the stroking was applied intentionally and according to the optimal properties of the specialized system in the skin for receiving affective touch.”

This system typically responds to slow, gentle stroking found in intimate relationships and encodes the pleasure of touch, Gentsch explains. In other words, this “social softness illusion” in the mind of the touch-giver is selective to the body parts and the stroking speeds that are most likely to elicit pleasure in the receiver.

“The illusion reveals a largely automatic and unconscious mechanism by which ‘giving pleasure is receiving pleasure’ in the touch domain,” Fotopoulou says.

In fact, social touch plays a powerful role in human life, from infancy to old age, with beneficial effects on physical and mental health. Many studies have focused on the benefits of touch for the person receiving it. For instance, premature infants benefit greatly from time spent in direct physical contact with their mothers. Yet, Fotopoulou and her colleagues say, remarkably little is known about the psychological benefits of actively touching others.

Earlier studies showed that softness and smoothness stimulate parts of the brain associated with emotion and reward. Therefore, this “illusion” that other people are softer ensures that reaching out and touching another person comes as its own reward.

This rewarding illusion acts as a kind of “social glue,” bonding people to each other. For example, touching a baby in a gentle manner seems to give the mother tactile pleasure, the researchers say, over and above any other thoughts or feelings the mother may have in the moment.

Fotopoulou says the next step is to examine the neurophysiological mechanisms involved in giving affective touch. They are also curious to examine any differences that may exist in the experience of this softness illusion among partners, friends, and strangers.


Story Source:

The above post is reprinted from materials provided by Cell Press. Note: Materials may be edited for content and length.


Journal Reference:

  1. Gentsch et al. Active Interpersonal Touch Gives Rise to the Social Softness Illusion. Current Biology, September 2015 DOI: 10.1016/j.cub.2015.07.049
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People worldwide — even nomads in Tanzania — think of colors the same way

Assigning names to colors combines nature, nurture

Date:
September 10, 2015
Source:
Ohio State University
Summary:
Would a color by any other name be thought of in the same way, regardless of the language used to describe it? According to new research, the answer is yes.

A new study examines how a culture of nomadic hunter-gatherers names colors, and shows that they group colors into categories that align with patterns of color grouping evident in 110 other world languages.

This study population — the Hadza people of Tanzania — has relatively few commonly shared color words in its language. During the study, the most common response by Hadza participants to a request to name a color was “Don’t know.”

However, the way the participants grouped the colors they did name — regardless of what name they used — tended to match color-naming conventions of Somali-speaking immigrants and native English speakers, and of many other cultures around the world.

“Looking at the Hadza data, we see a relatively modern color vocabulary emerging, but the color terms are distributed across the entire population,” said Delwin Lindsey, professor of psychology at The Ohio State University Mansfield Campus and lead author of the study. “We captured a point in time culturally where the stuff for creating a complex color naming exists, but it’s not in the head of any one individual. It’s distributed in bits and pieces across the culture.”

Scientists know a lot about how the human brain responds to seeing color — and that universality of perception makes color naming a good model for studying patterns in language change.

“This study provides a very useful framework for thinking about how the terms that are used to describe things in our environment actually emerge and evolve,” Lindsey said. “You can think of the words as species that are evolving — they are competing for space in our heads. So this is an example of cultural evolution that closely mirrors biological evolution.”

The research is published in the journal Current Biology.

Lindsey said the finding suggests that color naming is not a matter of nature versus nurture, but a combination of the two. The result also suggests that both prevailing theories about color naming apply around the world: Cultures create color names, but individuals from vastly different societies (Hadza, Somali and American) share the same perceptions of colors in their mind.

“Clearly, there are certain constraints within the mind that guide how colors are going to be grouped together,” said Lindsey, also a professor of optometry on Ohio State’s Columbus campus. “But this illustrates an interesting trade-off between culture and biology as determinants of human thought. There are cultural universals, but within each culture there is dramatic diversity. If the culture were playing the preeminent role, members of a society would establish conventions that they all agree on. But they’re clearly not all agreeing on anything.”

How does it play out in English? One person’s lilac shirt is called lavender by her neighbor.

Lindsey and collaborator Angela Brown, professor of optometry at Ohio State, reported in 2006 on their analysis of data of the World Color Survey, a collection of color names obtained by University of California, Berkeley researcher Paul Kay and associates from 2,616 people of 110 languages spoken by mostly preindustrial societies.

That analysis confirmed that, across cultures, people tend to classify hundreds of different chromatic colors into only eight distinct categories: red, green, yellow-or-orange, blue, purple, brown, pink and grue (green or blue).

In 2009, Lindsey and Brown published a second paper describing further analysis of the World Color Survey, in which they showed that four common, distinct groupings of color categories, which they called “motifs,” occur worldwide: black, white and red; black, white, red and gray; black, white, red and a single cool green or blue category; and black, white, red, green, blue and yellow. A surprising result was that the motifs observed within a society are nearly as diverse as those observed across cultures.

“We found that these motifs occurred with minor variations across 110 languages,” Brown said. “A person from Cameroon, Africa, can name colors more similarly to somebody from Northwestern Australia than to his Cameroon neighbor. And that Cameroon neighbor might be more similar to a different person in Northwestern Australia.”

Larger color vocabularies are generally associated in more technologically advanced societies.

“To try to get at how these motifs might emerge, we wanted to go as far back technologically as we could. That’s where the hunter-gatherers fit in,” Lindsey said.

He and Brown collaborated with co-corresponding author Coren Apicella and her colleague David Brainard, both on the psychology faculty at the University of Pennsylvania, to survey the Hadza people. Apicella has been working with the Hadza people for more than a decade.


Story Source:

The above post is reprinted from materials provided by Ohio State University. The original item was written by Emily Caldwell. Note: Materials may be edited for content and length.


Journal Reference:

  1. Delwin T. Lindsey et al. Hunter-Gatherer Color Naming Provides New Insight into the Evolution of Color Terms. Current Biology, September 2015 DOI: 10.1016/j.cub.2015.08.006