Featured Research

from universities, journals, and other organizations

Neuroscientists record novel responses to faces from single neurons in humans

Date:
September 30, 2011
Source:
California Institute of Technology
Summary:
Responding to faces is a critical tool for social interactions between humans. Without the ability to read faces and their expressions, it would be hard to tell friends from strangers upon first glance. Now, neuroscientists have discovered a novel response to human faces by looking at recordings from brain cells in neurosurgical patients.

This figure shows the kind of stimuli used in the study: whole faces (left) and only partly revealed faces. According to the researchers, the surprising finding was that although neurons respond most strongly to seeing the whole face, they actually respond much less to the middle panel than to the far right panel, even though the middle panel is more similar to the whole face.
Credit: Ralph Adolphs, California Institute of Technology

Responding to faces is a critical tool for social interactions between humans. Without the ability to read faces and their expressions, it would be hard to tell friends from strangers upon first glance, let alone a sad person from a happy one. Now, neuroscientists from the California Institute of Technology (Caltech), with the help of collaborators at Huntington Memorial Hospital in Pasadena and Cedars-Sinai Medical Center in Los Angeles, have discovered a novel response to human faces by looking at recordings from brain cells in neurosurgical patients.

The finding, described in the journal Current Biology, provides the first description of neurons that respond strongly when the patient sees an entire face, but respond much less to a face in which only a very small region has been erased.

"The finding really surprised us," says Ueli Rutishauser, first author on the paper, a former postdoctoral fellow at Caltech, and now a visitor in the Division of Biology. "Here you have neurons that respond well to seeing pictures of whole faces, but when you show them only parts of faces, they actually respond less and less the more of the face you show. That just seems counterintuitive."

The neurons are located in a brain region called the amygdala, which has long been known to be important for the processing of emotions. However, the study results strengthen a growing belief among researchers that the amygdala has also a more general role in the processing of, and learning about, social stimuli such as faces.

Other researchers have described the amygdala's neuronal response to faces before, but this dramatic selectivity -- which requires the face to be whole in order to elicit a response -- is a new insight.

"Our interpretation of this initially puzzling effect is that the brain cares about representing the entire face, and needs to be highly sensitive to anything wrong with the face, like a part missing," explains Ralph Adolphs, senior author on the study and Bren Professor of Psychology and Neuroscience and professor of biology at Caltech. "This is probably an important mechanism to ensure that we do not mistake one person for another and to help us keep track of many individuals."

The team recorded brain-cell responses in human participants who were awaiting surgery for drug-resistant epileptic seizures. As part of the preparation for surgery, the patients had electrodes implanted in their medial temporal lobes, the area of the brain where the amygdala is located. By using special clinical electrodes that have very small wires inserted, the researchers were able to observe the firings of individual neurons as participants looked at images of whole faces and partially revealed faces. The voluntary participants provided the researchers with a unique and very rare opportunity to measure responses from single neurons through the implanted depth electrodes, says Rutishauser.

"This is really a dream collaboration for basic research scientists," he says. "At Caltech, we are very fortunate to have several nearby hospitals at which the neurosurgeons are interested in such collaborative medical research."

The team plans to continue their studies by looking at how the same neurons respond to emotional stimuli. This future work, combined with the present study results, could be highly valuable for understanding a variety of psychiatric diseases in which this region of the brain is thought to function abnormally, such as mood disorders and autism.


Story Source:

The above story is based on materials provided by California Institute of Technology. Note: Materials may be edited for content and length.


Journal Reference:

  1. Ueli Rutishauser, Oana Tudusciuc, Dirk Neumann, Adam N. Mamelak, A. Christopher Heller, Ian B. Ross, Linda Philpott, William W. Sutherling, Ralph Adolphs. Single-Unit Responses Selective for Whole Faces in the Human Amygdala. Current Biology, 29 September 2011 DOI: 10.1016/j.cub.2011.08.035

Cite This Page:

California Institute of Technology. "Neuroscientists record novel responses to faces from single neurons in humans." ScienceDaily. ScienceDaily, 30 September 2011. <www.sciencedaily.com/releases/2011/09/110929122753.htm>.
California Institute of Technology. (2011, September 30). Neuroscientists record novel responses to faces from single neurons in humans. ScienceDaily. Retrieved August 1, 2014 from www.sciencedaily.com/releases/2011/09/110929122753.htm
California Institute of Technology. "Neuroscientists record novel responses to faces from single neurons in humans." ScienceDaily. www.sciencedaily.com/releases/2011/09/110929122753.htm (accessed August 1, 2014).

Share This




More Mind & Brain News

Friday, August 1, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Dieting At A Young Age Might Lead To Harmful Health Habits

Dieting At A Young Age Might Lead To Harmful Health Habits

Newsy (July 30, 2014) Researchers say women who diet at a young age are at greater risk of developing harmful health habits, including eating disorders and alcohol abuse. Video provided by Newsy
Powered by NewsLook.com
It's Not Just Facebook: OKCupid Experiments With Users Too

It's Not Just Facebook: OKCupid Experiments With Users Too

Newsy (July 29, 2014) If you've been looking for love online, there's a chance somebody has been looking at how you're looking. Video provided by Newsy
Powered by NewsLook.com
How Your Face Can Leave A Good Or Bad First Impression

How Your Face Can Leave A Good Or Bad First Impression

Newsy (July 29, 2014) Researchers have found certain facial features can make us seem more attractive or trustworthy. Video provided by Newsy
Powered by NewsLook.com
Losing Sleep Leaves You Vulnerable To 'False Memories'

Losing Sleep Leaves You Vulnerable To 'False Memories'

Newsy (July 27, 2014) A new study shows sleep deprivation can make it harder for people to remember specific details of an event. 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