Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Scientists uncover new mechanism for the amygdala in fear recognition

06.01.2005


A look of fear on another person’s face is instantly recognizable. The split-second ability of the amygdala, a small, almond-shaped structure deep in the brain, distinguishes fear in facial expressions. In particular, the amygdala relies heavily on visual information contained in the eye region to detect fear.



A new study by scientists at the University of Iowa, the California Institute of Technology and their colleagues sheds more light on how the amygdala works. The study, published in the Jan. 6 issue of Nature, suggests that the mechanism by which the amygdala contributes to processing visual information about facial expressions is by actively directing a person’s gaze to the eye region to seek out and fixate on the critical visual cues for fear.

"People often think of the brain as passively receiving information from the senses about the world. This study shows that there are mechanisms in the brain that allow us to actively seek out information in the environment in the first place," said Ralph Adolphs, Ph.D., UI adjunct professor of neurology and professor of psychology and neuroscience at the California Institute of Technology.


The study extends the group’s decade-long investigation involving patients who are essentially unable to recognize fearful expressions because of a damaged amygdala. The current series of experiments showed that a particular patient fails to make use of information about the eyes in faces, and one reason for that is that she fails to look at the eyes in faces in the first place.

The researchers found that they could restore the patient’s ability to distinguish fear in facial expressions to normal levels by specifically instructing her to look at the eye region. However, this instruction had to be given each time the patient viewed a face otherwise she resumed her abnormal gaze pattern, did not fixate on the eyes and was not able to discern fear.

The findings suggest that the amygdala damage disrupts the patient’s ability to direct her own gaze toward the eyes in other people’s faces, which deprives her of the critical visual cues to detect fearful expressions.

If the patient could be trained to always look at the eyes, the researchers suggest that her impaired fear recognition could be rescued permanently. The study may have implications for conditions such as autism, where patients also show abnormal fixation on facial features and have a disrupted ability to interpret emotion from facial expressions.

"That the amygdala is critical for recognizing fear expressions has been evident from prior studies," said Antonio Damasio, M.D., Ph.D., the Maurice Van Allen Professor and head of neurology at the UI Roy J. and Lucille A. Carver College of Medicine. "The new findings, however, suggest a specific mechanism for the impairments of fear recognition that can be found in patients with amygdala damage."

"This study tells us how it is that the amygdala plays a role in recognizing fear and in so doing it shows us that the amygdala isn’t specialized just to detect fear in faces but really serves a more abstract and general role in seeking out potentially important and salient information in the environment," Adolphs added.

Jennifer Brown | EurekAlert!
Further information:
http://www.uiowa.edu

More articles from Health and Medicine:

nachricht Investigators may unlock mystery of how staph cells dodge the body's immune system
22.09.2017 | Cedars-Sinai Medical Center

nachricht Monitoring the heart's mitochondria to predict cardiac arrest?
21.09.2017 | Boston Children's Hospital

All articles from Health and Medicine >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: The pyrenoid is a carbon-fixing liquid droplet

Plants and algae use the enzyme Rubisco to fix carbon dioxide, removing it from the atmosphere and converting it into biomass. Algae have figured out a way to increase the efficiency of carbon fixation. They gather most of their Rubisco into a ball-shaped microcompartment called the pyrenoid, which they flood with a high local concentration of carbon dioxide. A team of scientists at Princeton University, the Carnegie Institution for Science, Stanford University and the Max Plank Institute of Biochemistry have unravelled the mysteries of how the pyrenoid is assembled. These insights can help to engineer crops that remove more carbon dioxide from the atmosphere while producing more food.

A warming planet

Im Focus: Highly precise wiring in the Cerebral Cortex

Our brains house extremely complex neuronal circuits, whose detailed structures are still largely unknown. This is especially true for the so-called cerebral cortex of mammals, where among other things vision, thoughts or spatial orientation are being computed. Here the rules by which nerve cells are connected to each other are only partly understood. A team of scientists around Moritz Helmstaedter at the Frankfiurt Max Planck Institute for Brain Research and Helene Schmidt (Humboldt University in Berlin) have now discovered a surprisingly precise nerve cell connectivity pattern in the part of the cerebral cortex that is responsible for orienting the individual animal or human in space.

The researchers report online in Nature (Schmidt et al., 2017. Axonal synapse sorting in medial entorhinal cortex, DOI: 10.1038/nature24005) that synapses in...

Im Focus: Tiny lasers from a gallery of whispers

New technique promises tunable laser devices

Whispering gallery mode (WGM) resonators are used to make tiny micro-lasers, sensors, switches, routers and other devices. These tiny structures rely on a...

Im Focus: Ultrafast snapshots of relaxing electrons in solids

Using ultrafast flashes of laser and x-ray radiation, scientists at the Max Planck Institute of Quantum Optics (Garching, Germany) took snapshots of the briefest electron motion inside a solid material to date. The electron motion lasted only 750 billionths of the billionth of a second before it fainted, setting a new record of human capability to capture ultrafast processes inside solids!

When x-rays shine onto solid materials or large molecules, an electron is pushed away from its original place near the nucleus of the atom, leaving a hole...

Im Focus: Quantum Sensors Decipher Magnetic Ordering in a New Semiconducting Material

For the first time, physicists have successfully imaged spiral magnetic ordering in a multiferroic material. These materials are considered highly promising candidates for future data storage media. The researchers were able to prove their findings using unique quantum sensors that were developed at Basel University and that can analyze electromagnetic fields on the nanometer scale. The results – obtained by scientists from the University of Basel’s Department of Physics, the Swiss Nanoscience Institute, the University of Montpellier and several laboratories from University Paris-Saclay – were recently published in the journal Nature.

Multiferroics are materials that simultaneously react to electric and magnetic fields. These two properties are rarely found together, and their combined...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

“Lasers in Composites Symposium” in Aachen – from Science to Application

19.09.2017 | Event News

I-ESA 2018 – Call for Papers

12.09.2017 | Event News

EMBO at Basel Life, a new conference on current and emerging life science research

06.09.2017 | Event News

 
Latest News

Penn first in world to treat patient with new radiation technology

22.09.2017 | Medical Engineering

Calculating quietness

22.09.2017 | Physics and Astronomy

Hope to discover sure signs of life on Mars? New research says look for the element vanadium

22.09.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>