The brain uses an internal model of the outer visible world to create such illusions. Frankfurt Scientists have now revealed the functionality of this “mind’s eye”. By using a new mathematical model they were able to describe the behavior of brain cells more accurately.
In everyday life, we often see objects occluding each other, such as a branch of a bush hiding another in this figure (red box). The image of the two objects is projected into the brain in which specialized nerve cells react to certain image traits with increased activity. To understand the image, the brain has to decompose it into its original components (here: the two branches). A new mathematical model of this decomposition now predicts that there must be many nerve cells responding to globular features in order to understand occlusions (here: new neural response). This type of cells has been observed for some time, but up to now has never been linked to visual occlusions. Figure: Jörg Lücke / Bornschein J. et al. (2013): Are V1 simple cells optimized for visual occlusions? A comparative study. PLoS Computational Biology 9(6): e1003062.
In contrast to previous models, this model takes into account occlusions between objects in the world. The researchers have thus shown that our brain activity is much more directly connected with the properties of the outside world than anticipated.
In 1981, the neuroscientists Hubel and Wiesel were awarded the Nobel Prize for the discovery of brain cells that react with high activity to the edges of objects in images. Their findings have shown that our brain activity is related to features such as edges of objects. Later on, mathematical models were able to explain why neurons respond to certain object features.
These models describe how the brain generates an internal image —yet, so far, they reflect rather insufficiently the actual structure of natural images. Occlusions between objects are ignored, for instance, although they are ubiquitous in the visible world. A certain type of nerve cell— only known for a few years—is difficult to be described with the current simplified models.
Researchers at the Bernstein Focus Neurotechnology Frankfurt, at the Goethe-University Frankfurt and at the Frankfurt Institute for Advanced Studies have now shown that the behavior of these new brain cells can be better characterized in computational models when further information is taken into account.In the study, the scientists compared conventional models with one taking occlusions between objects into account. The new descriptive model was better at predicting the functional traits of this special type of nerve cells. The result also provides hints at the function of these neurons: "There are other possible explanations why there are such cells in our brain," says Jörg Lücke, "but our results indicate the encoding of occlusions as the most plausible explanation at hand."
Weitere Informationen:http://fias.uni-frankfurt.de/de/cnml Lab’s website
Mareike Kardinal | idw
Scientists uncover the role of a protein in production & survival of myelin-forming cells
19.07.2018 | Advanced Science Research Center, GC/CUNY
NYSCF researchers develop novel bioengineering technique for personalized bone grafts
18.07.2018 | New York Stem Cell Foundation
A new manufacturing technique uses a process similar to newspaper printing to form smoother and more flexible metals for making ultrafast electronic devices.
The low-cost process, developed by Purdue University researchers, combines tools already used in industry for manufacturing metals on a large scale, but uses...
For the first time ever, scientists have determined the cosmic origin of highest-energy neutrinos. A research group led by IceCube scientist Elisa Resconi, spokesperson of the Collaborative Research Center SFB1258 at the Technical University of Munich (TUM), provides an important piece of evidence that the particles detected by the IceCube neutrino telescope at the South Pole originate from a galaxy four billion light-years away from Earth.
To rule out other origins with certainty, the team led by neutrino physicist Elisa Resconi from the Technical University of Munich and multi-wavelength...
For the first time a team of researchers have discovered two different phases of magnetic skyrmions in a single material. Physicists of the Technical Universities of Munich and Dresden and the University of Cologne can now better study and understand the properties of these magnetic structures, which are important for both basic research and applications.
Whirlpools are an everyday experience in a bath tub: When the water is drained a circular vortex is formed. Typically, such whirls are rather stable. Similar...
Physicists working with Roland Wester at the University of Innsbruck have investigated if and how chemical reactions can be influenced by targeted vibrational excitation of the reactants. They were able to demonstrate that excitation with a laser beam does not affect the efficiency of a chemical exchange reaction and that the excited molecular group acts only as a spectator in the reaction.
A frequently used reaction in organic chemistry is nucleophilic substitution. It plays, for example, an important role in in the synthesis of new chemical...
Optical spectroscopy allows investigating the energy structure and dynamic properties of complex quantum systems. Researchers from the University of Würzburg present two new approaches of coherent two-dimensional spectroscopy.
"Put an excitation into the system and observe how it evolves." According to physicist Professor Tobias Brixner, this is the credo of optical spectroscopy....
13.07.2018 | Event News
12.07.2018 | Event News
03.07.2018 | Event News
20.07.2018 | Power and Electrical Engineering
20.07.2018 | Information Technology
20.07.2018 | Materials Sciences