Featured Research

from universities, journals, and other organizations

A facial expression is worth a thousand words

Date:
December 31, 2009
Source:
Max Planck Institute for Biological Cybernetics
Summary:
Moving pictures are more suitable to interpret the mood of a person than a static photograph. Communication is a central aspect of everyday life, a fact that is reflected in the wide variety of ways that people exchange information, not only with words, but also using their face and body. Scientists have now found out that we are able to recognize facial expressions in motion far better than in a static photograph. The video sequence needs to be at least as long as one tenth of a second to gain this dynamic advantage.

Interpreting this facial expression correctly (as a "baffled" expression) is very difficult based on this photo alone. When showing the corresponding video sequence, however, recognition becomes easy, which underlines the importance of the temporal dimension for effective communication.
Credit: Christian Wallraven / Max Planck Institute for Biological Cybernetics

Communication is a central aspect of everyday life, a fact that is reflected in the wide variety of ways that people exchange information, not only with words, but also using their face and body. Scientists from the Max Planck Institute for Biological Cybernetics in Tόbingen, Germany, found out that we are able to recognize facial expressions in motion -- for example, in a movie -- far better than in a static photograph. The video sequence needs to be at least as long as one tenth of a second to gain this dynamic advantage.

A facial expression can state a lot. A nod indicates understanding, a frown may say: "Please explain that again!" Scientists from the Max Planck Institute for Biological Cybernetics discovered that we are able to classify an expression much better when it moves naturally rather than when it is "frozen" in a photograph. In order to gain the advantage of dynamic information, we need to see the expression moving for at least 100 milliseconds. If the video sequence is shorter, our brain is less capable of interpreting the facial motion. Some expressions rely on changes in head orientation, for example, a nod or a shake of the head, others on the complex deformation of facial parts, such as wrinkling our nose to signalize disgust or a frown.

In order to examine to what extent we are able to recognize -- based on facial expressions -- the mood of a person with whom we are interacting, the scientists showed participants pictures of humans with various different expressions. Among them were simple, emotional expressions, such as "happy" and "sad," but also more complex ones such as agreement, confusion, or surprise, which are usually used to emphasize or modify statements in a conversation. In order to investigate whether these expressions are recognized more easily in motion or in static pictures, a short video sequence was shown to the participants. The video recordings began at a neutral expression, showed an emotion, and ended at the last frame before the face started to head back to a neutral expression. The frame used in the static conditions was the last, so-called 'peak' frame of each dynamic sequence. The participants were then asked to identify the expressions based on the shown sequence or single frame.

In further experiments, the video sequences were converted to a series of photographs that was shown to the participants. Nevertheless, the expressions were still recognized more accurately in the video sequence. This showed that the dynamic advantage is not due to the presence of multiple images, but that some form of dynamic information is being used. In order to figure the degree to which facial expression recognition relies on natural movement, the frames were presented as a movie, but in a random order. Comparisons of the performance in this scrambled condition to the original video sequence shows that the recognition rates were still higher in the original than in the scrambled version.

The chronological direction is of importance as well. If the video sequences are temporally reversed, they are again identified less accurately. Finally, the more temporal information we receive, the better we are able to recognize expressions -- at least up to 100 milliseconds. The results show that neither pictures, nor motion alone are of importance, but that we need a combination of the correct temporal sequence and the correct facial motion to reliably interpret facial expressions.

"Facial expressions, like gestures and body motion, are a dynamic phenomenon and need to be investigated with the help of video sequences in order to get a better understanding of the dynamic information that is being processed," says Dr. Christian Wallraven, co-author of the study. "Our results also have implications for the area of computer animation, since its goal is to create artificial avatars and facial animations that are able to communicate realistically and believably," says the physicist and perception scientist.

For more information, see: http://www.kyb.mpg.de/projects.html?user=walli


Story Source:

The above story is based on materials provided by Max Planck Institute for Biological Cybernetics. Note: Materials may be edited for content and length.


Journal Reference:

  1. Cunningham, D. W. & Wallraven, C. Dynamic information for the recognition of conversational expressions. Journal of Vision, 9 (13):7, 1-17 DOI: 10.1167/9.13.7

Cite This Page:

Max Planck Institute for Biological Cybernetics. "A facial expression is worth a thousand words." ScienceDaily. ScienceDaily, 31 December 2009. <www.sciencedaily.com/releases/2009/12/091223215119.htm>.
Max Planck Institute for Biological Cybernetics. (2009, December 31). A facial expression is worth a thousand words. ScienceDaily. Retrieved August 27, 2014 from www.sciencedaily.com/releases/2009/12/091223215119.htm
Max Planck Institute for Biological Cybernetics. "A facial expression is worth a thousand words." ScienceDaily. www.sciencedaily.com/releases/2009/12/091223215119.htm (accessed August 27, 2014).

Share This




More Computers & Math News

Wednesday, August 27, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Hackerspace Provides Hackers Creative Haven

Hackerspace Provides Hackers Creative Haven

AP (Aug. 27, 2014) — HeatSync Labs, a so-called hackerspace in Mesa, Arizona provides members and the public alike a space to allow their creative juices to flow and make their tech dreams into a reality. (Aug 27) Video provided by AP
Powered by NewsLook.com
Why A 12.9-Inch iPad Would Make Sense For Apple

Why A 12.9-Inch iPad Would Make Sense For Apple

Newsy (Aug. 27, 2014) — There are two big knocks against the iPad — productivity limits and slumping sales. Here's how a bigger iPad could fix both of Apple's problems. Video provided by Newsy
Powered by NewsLook.com
Smartphone App Tracks Your Heart Rate

Smartphone App Tracks Your Heart Rate

Ivanhoe (Aug. 27, 2014) — A new app that can track your heart rate 24/7 is available for download in your app store and its convenience could save your life. Video provided by Ivanhoe
Powered by NewsLook.com
Nationwide Time Warner Internet Crash Results In More Bad PR

Nationwide Time Warner Internet Crash Results In More Bad PR

Newsy (Aug. 27, 2014) — The nationwide Internet crash resulted in millions of customers' internet connection to go out for hours. Video provided by Newsy
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
 
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:  

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:  

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile iPhone Android Web
Follow Facebook Twitter Google+
Subscribe RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins