Navigation Links
Where we change our mind

Whether finding your way through an unfamiliar neighborhood to a friend's house or deciding on a political candidate, your brain is adept at adapting. It can make decisions based on incomplete information and update those decisions based on new information.

The nature of such sophisticated decision making in the cerebral cortex, which is responsible for high-level processing, has been "poorly studied and little understood," according to Wako Yoshida and Shin Ishii of the Nara Institute of Science and Technology. Now, however, in an article in the June 1, 2006, Neuron, they describe experiments that enabled them to tease apart how different regions of the cerebral cortex process uncertain information and integrate it into decision making.

In particular, their aim was to analyze subjects' navigation through a virtual maze, to explore how different cortical regions function in solving "partially observable decision-making problems."

"In navigation tasks, such as that investigated here, an individual must constantly maintain an estimate as to his/her current location as a guide for deciding the next turn," they wrote, "but in the absence of incontrovertible a priori information, this estimate is best represented by the subject's belief. As information is acquired through observation, this belief may become increasingly convincing or alternatively may be discarded in favor of a new one. This is an intuitive way of making estimations that are appropriate for many real-world behaviors, adopted also by a wide variety of intelligent machines.?" they wrote.

In their experiments, the researchers first taught volunteer subjects the layout of a computer-generated 3D "wire-frame" maze. Then, while the subjects' brains were being scanned using functional magnetic resonance, the researchers "placed" the subjects in different parts of the maze and analyzed activation of cerebral cortical regions as the subjects made a series of decisions to navigate t heir way to a specified goal. Functional MRI involves using harmless magnetic fields and radio waves to image blood flow in brain regions, which reflects activity.

Importantly, Yoshida and Ishii used sophisticated statistical probabilistic analysis of the subjects' movements to overcome a major obstacle to such studies. That obstacle is that the beliefs of the subjects during the experiment could not be determined unequivocally; thus, those beliefs could not be correlated with brain function.

However, the researchers' statistical analysis of the subject's navigation decisions enabled them to infer which of two "cognitive states" the subject was in, to give the researchers insight into which cortical regions were active during the states. One such cognitive state was a belief about where the subject was in the maze, and the other was a set of "operant" states. These operant states were a "proceed or update mode" or a "reevaluate or back-track mode."

Analyzing the brain regions active during these states, Yoshidi and Ishii pinpointed which regions of the subjects' cerebral cortex were active during the different processes involved in "changing their minds." Specifically, the researchers found that "belief maintenance" processes are performed principally by a region called the anterior prefrontal cortex, and "belief back-track" processes occur in the medial prefrontal cortex.

"Our results provide evidence that activity in different regions of the prefrontal cortex reflect critical computational components involved in decision making in uncertain environments," concluded the researchers. "This fits well with the proposed role of these regions in decision making, which is likely to be crucial in complex real-world environments. We also illustrate the utility of statistical model-based inference and regression in delineating key task parameters that may be represented in spatially distinct brain regions," they concluded.


'"/>

Source:Cell Press


Related biology news :

1. Where bacteria get their genes
2. Where Bacteria Get Their Genes
3. Where jumping genes fear to tread
4. Where have all the butterflies gone?
5. Elusive HIV shape change revealed; Key clue to how virus infects cells
6. Researchers trace evolution to relatively simple genetic changes
7. Plants defy Mendels inheritance laws, may prompt textbook changes
8. Small species back-up giant marsupial climate change extinction claim
9. Africa to take it on chin again with climate change
10. Fox Chase study shows that weakened T-cell receptor signals change T-cell lineage
11. By creating molecular bridge, scientists change function of a protein
Post Your Comments:
*Name:
*Comment:
*Email:


(Date:6/2/2016)... NEW YORK , June 2, 2016   The ... (Weather), is announcing Watson Ads, an industry-first capability in which ... advertising, by being able to ask questions via voice or ... Marketers have long ... with the consumer, that can be personal, relevant and valuable; ...
(Date:5/20/2016)...  VoiceIt is excited to announce its new ... By working together, VoiceIt and VoicePass will offer ... take slightly different approaches to voice biometrics, collaboration ... usability. Both ... "This marketing and technology partnership allows ...
(Date:5/3/2016)...  Neurotechnology, a provider of high-precision biometric identification ... Identification System (ABIS) , a complete system for ... can process multiple complex biometric transactions with high ... face or iris biometrics. It leverages the core ... MegaMatcher Accelerator , which have been used in ...
Breaking Biology News(10 mins):
(Date:6/27/2016)... -- Global demand for enzymes is forecast to grow ... billion.  This market includes enzymes used in industrial ... animal feed, and other markets) and specialty applications ... beverages will remain the largest market for enzymes, ... containing enzymes in developing regions.  These and other ...
(Date:6/27/2016)... -- Sequenom, Inc. (NASDAQ: SQNM ), a life ... development of innovative products and services, announced today that ... denied its petition to review decisions by ... Patent No. 6,258,540 (",540 Patent") are not patent eligible ... Court,s Mayo Collaborative Services v. Prometheus Laboratories decision.  In ...
(Date:6/27/2016)... Diego, CA (PRWEB) , ... June 27, 2016 , ... ... solutions for clinical trials, announced today the Clinical Reach Virtual Patient Encounter ... their care circle with the physician and clinical trial team. , Using the CONSULT ...
(Date:6/27/2016)... ... June 27, 2016 , ... ... will join the faculty of the University of North Carolina Kenan-Flagler Business ... strategy and entrepreneurship at UNC Kenan-Flagler, with a focus on the school’s international ...
Breaking Biology Technology: