Navigation Links
How the brain handles surprise, good and bad
Date:9/19/2007

Whether its a mugger or a friend who jumps out of the bushes, youre still surprised. But your responseto flee or to hugmust be very different. Now, researchers have begun to distinguish the circuitry in the brains emotion center that processes surprise from the circuitry that processes the aversive or reward valence of a stimulus.

C. Daniel Salzman and colleagues published their findings in the September 20, 2007 issue of the journal Neuron, published by Cell Press.

Animals and humans learn to approach and acquire pleasant stimuli and to avoid or defend against aversive ones, wrote the researchers. However, both pleasant and aversive stimuli can elicit arousal and attention, and their salience or intensity increases when they occur by surprise. Thus, adaptive behavior may require that neural circuits compute both stimulus valenceor valueand intensity.

The researchers concentrated their study on the amygdala, known to be the brain center that processes the emotional substance of sensory input and helps shape behavioral response to that input.

In their studies, which used monkeys, the researchers performed two types of experiments as they recorded the electrical activity of neurons in the animals amygdala. In one experiment, they taught the monkeys to associate a pattern on a TV monitor with either the rewarding experience of a sip of water or an unpleasant puff of air to the face. The researchers measured how well the monkeys learned the association by recording how frequently the animals anticipated the water sip or the air puff by, respectively, licking the water spout or blinking. This experiment was intended to establish whether there were specific amygdala neurons activated by rewarding or aversive stimuli.

In the other experiment, the researchers surprised the monkeys by randomly delivering either the water sip or the air puffwhich aimed to establish whether the amygdala harbored specific surprise-processing circuitry.

The researchers analyses of the activity of the amygdala neurons did reveal different types of neurons. Some neurons responded to either the reward or the aversive stimulus, but not both. However, the activity of distinctly different sets of neurons was affected by expectation of either a reward or an aversive experience.

These different neuronal populations may subserve two sorts of processes mediated by the amygdala: those activated by surprising reinforcements of both valencessuch as enhanced arousal and attentionand those that are valence-specific, such as fear or reward-seeking behavior, wrote the researchers.

They concluded that These different types of response properties may underlie the role of the amygdala in multiple processes related to emotion, including reinforcement learning, attention, and arousal. Future work must develop experimental approaches for unraveling the complex anatomical circuitry and mechanisms by which amygdala neurons influence learning and the many emotional processes related to the valence and intensity of reinforcing stimuli.


'/>"/>

Contact: Nancy Wampler
nwampler@cell.com
617-386-2121
Cell Press
Source:Eurekalert

Related biology news :

1. Controversial drug shown to act on brain protein to cut alcohol use
2. Drug That Tags Decision-making Areas Of The Brain May Aid
3. Mouse brain cells rapidly recover after Alzheimers plaques are cleared
4. NYU Study Reveals How Brains Immune System Fights Viral Encephalitis
5. Mouse brain tumors mimic those in human genetic disorder
6. New imaging method gives early indication if brain cancer therapy is effective, U-M study shows
7. First atlas of key brain genes could speed research on cancer, neurological diseases
8. Transport System Smuggles Medicines Into Brain
9. Bird Brains Show How Trial and Error May Contribute to Learning
10. VCU Researchers Identify Networks Of Genes Responding To Alcohol In The Brain
11. Wiley announces publication of Databasing the Brain
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:5/3/2016)... VILNIUS, Lithuania , May 3, 2016 /PRNewswire/ ... today released the MegaMatcher Automated Biometric Identification ... deployment of large-scale multi-biometric projects. MegaMatcher ABIS can ... and accuracy using any combination of fingerprint, face ... of MegaMatcher SDK and MegaMatcher ...
(Date:4/19/2016)... , UAE, April 20, 2016 ... be implemented as a compact web-based "all-in-one" system solution ... the biometric fingerprint reader or the door interface with ... of modern access control systems. The minimal dimensions of ... ID readers into the building installations offer considerable freedom ...
(Date:3/31/2016)... , March 31, 2016 ... ) ("LegacyXChange" or the "Company") LegacyXChange is ... users of its soon to be launched online site ... https://www.youtube.com/channel/UCyTLBzmZogV1y2D6bDkBX5g ) will also provide potential shareholders ... of DNA technology to an industry that is notorious ...
Breaking Biology News(10 mins):
(Date:6/27/2016)... ... 2016 , ... Newly created 4Sight Medical Solutions ... healthcare market. The company's primary focus is on new product introductions, to include ... are necessary to help companies efficiently bring their products to market. , The ...
(Date:6/24/2016)... TOKYO , June 24, 2016  Regular discussions on ... to take place between the two entities said Poloz. ... in Ottawa , he pointed to the ... and the federal government. ... Poloz said, "Both institutions have common economic goals, why not ...
(Date:6/23/2016)... ... June 23, 2016 , ... ... of its second eBook, “Clinical Trials Patient Recruitment and Retention Tips.” Partnering with ... in this eBook by providing practical tips, tools, and strategies for clinical researchers. ...
(Date:6/23/2016)... , June 23, 2016 A person commits a ... crime scene to track the criminal down. An ... Food and Drug Administration (FDA) uses DNA evidence to track ... Sound far-fetched? It,s not. The FDA has increasingly ... support investigations of foodborne illnesses. Put as simply as possible, ...
Breaking Biology Technology: