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Issue 22, January 2012
bulletHow the Brain Processes Visual Information
bulletInterview: Dr. Udo Ernst on How We See the World
bulletVisual Illusions: How Our Brains Translate 3D Images
bulletNew Model Tests Visual Stability in Darkness
bulletInnovation: EBS NEXT WAVE Therapy to Treat Vision and Speech Impairment Caused by Stroke
bulletEvent Announcement: Which Way Did It Go?
article1How the Brain Processes Visual Information
Our eyes are our window to the world - and in order to see, we need light.
Light waves pass through the structures of the eye and are focused on the retina. The light-sensitive photoreceptors of the retina initiate a cascade of electro-chemical signals that are transmitted to the brain. The visual system structures of the brain decode these signals, resulting in what we call "visual information."
But we do not consciously perceive all the visual information that enters through our eyes. Much of that information is redundant or constant, thus our brain focuses on a few important things, such as changes in visual space, object movement or features requiring special attention. Visual perception is an ongoing process involving selecting, grouping, and interpreting visual information. In order to find out if perceptual changes serve as keys to our consciousness, scientists in Tübingen used image processing effects to decipher brain functions.
This issue of E-NNOVATION GERMANY introduces several approaches to how we see the world. Dr. Udo Ernst's research demonstrates that learned behaviors, such as context, knowledge, and intention, influence visual processing in the brain. Studies from the Max Planck Institute for Biological Cybernetics and the Chemnitz University of Technology describe how we perceive visual illusions of 3D images or darkness. If you are interested in learning more about research focusing on the vision-brain-relationship, join us on Twitter @gcri_ny

Dr. Udo Ernst
article2Interview: Dr. Udo Ernst on How We See the World
Udo Ernst is a theoretical physicist turned neuroscientist. His research focuses on how the brain processes visual information, for which he envisages possible applications in the visual typewriter or a novel cortical visual prosthesis. One type of visual typewriter is already used, for example, by paralyzed patients who can only communicate with their eyes. The typewriter allows them to form words by moving their eyes from letter to letter. Dr. Ernst's proposed model would instead be connected to a brain-computer interface (BCI), thereby significantly accelerating the process by reading the patient's brain signals. His research on a cortical visual prosthesis seeks to use signals from the visual system to interact with the environment, via e-mail, for example. In this GCRI Interview, Dr. Ernst, who received the 2010 Bernstein Award for Computational Neuroscience, explains how our brains analyze visual scenes to create representations of reality. He also discusses how factors, such as context, knowledge, and intention, influence our visual perception of reality and how we can learn to enhance this perceptual ability. To read the interview, click here.
Dr. Ernst currently works as a postdoctoral fellow and coordinator of the Bernstein Group for Computational Neuroscience Bremen at the University of Bremen, where he leads the "Feature Integration in Visual Cortex" project. For more information, or to contact him directly, please click here

Visual Illusion
article3Visual Illusions: How Our Brains Translate 3D Images
When we look at a flat television screen or photograph, our brains interpret the image, allowing us to create a three-dimensional image in our mind from the two-dimensional image impinging on our retina. Clues to the mystery of how the brain is able to make this transformation were recently obtained from a clever set of experiments conducted by Roland Fleming and an international team of scientists from Giessen University, Yale University and the Max Planck Institute for Biological Cybernetics in Tübingen. The team created pictures with special two-dimensional patterns that stimulate specific neurons in the visual cortex, so-called "edge detector" cells. Heinrich Buelthoff, Director at the MPI for Biological Cybernetics, explained that observers in the experiments were asked to adjust small probes on the pictures and to report what they saw. Using the probe settings, the researchers were able to reconstruct the perceived three- dimensional shapes. Thus, a new visual illusion has enabled this international team to identify the "edge detector" cells as important components in the mental transformation of two-dimensional retinal images into three-dimensional mental images. For more information, please click here.

Photo: A new illusion in which random noise (left) is made to look like a 3D shape (right). R. Fleming/MPI for Biological Cybernetics

Brandenburger Tor
article4New Model Tests Visibility in Darkness
Our visual system allows us to sample the environment with very high resolution by shifting our gaze from one location to the next. If we scan the surface of a particular object, such as the Brandenburger Tor in Berlin (shown on the left), with rapid eye movements, called saccades, we can enjoy the richness of details in the structure of this object. While the object itself appears well localized in the outside world, our retina is faced with a sequence of snapshots intermitted by blur owing to the retinal slip. While the ultimate explanation of perceptual stability still seems out of reach, present neurocomputational research addresses several different phenomena that appear related to perceptual stability.
Arnold Ziesche and Fred H. Hamker from the Chemnitz University of Technology, Germany, propose a new model of perisaccadic mislocalization in complete darkness. Their work at the computer science department includes the development of brain function models by integrating findings from neuroscience, brain anatomy, and psychology. According to their model, the localization of a stimulus in total darkness requires information about gaze direction during fixation and knowledge about the intended eye movement. This anticipation of an eye movement updates an internal spatial reference system even before the eyes start to move. Future work will expand the model, applying it to real world scenes and ultimately as a device for cognitive robots. For more information, click here.

EBS Technology
article5Innovation: EBS NEXT WAVE Therapy to Treat Vision and Speech Impairment Caused by Stroke
Stroke is one of the most common causes of death in the U.S. and Europe. However, due to improved emergency and recovery strategies, an increasing number of stroke victims survive - albeit with serious long-term disabilities. Current treatments for stroke-related vision and speech impairment mainly involve long-term individual training, such as physical, speech, and ergotherapy. EBS Technologies GmbH, near Berlin, recently developed the EBS NEXT WAVE™ therapy, an approach that fills a great medical need as there are few therapeutic solutions for treating disabilities incurred after stroke and brain trauma.
The EBS NEXT WAVE™ therapy is a non-invasive electrical brain stimulation device that activates residual brain structures through the enhancement of synaptic transmission and brain synchronization. By using this innovative device, EBS aims to achieve neurological recovery that leads to a normalization of vision and speech deficits. The process includes measurements of each patient´s EEG patterns for individual frequency and current strength customization, and uses pulsed electrical stimulations of low currents, which are applied by electrodes. A prototype has been tested in clinical trials, with more than 1,000 patients in observational studies, for example, at the Charité University Hospital in Berlin. EBS NEXT WAVE™ is expected to launch in the German market in the first quarter of 2012, after receiving the European Commission's CE certification for meeting the EU safety, health, and environmental protection standards. For more information, visit www.ebstech.de.

Brain image
article6Event Announcement: Which Way Did It Go?
At the GCRI, on Tuesday, January 31, 2012, David Fitzpatrick (Max Planck Florida Institute) and Joshua Sanes (Harvard University) will discuss new insights into the organization and development of brain circuits that compute motion direction.
They have each pioneered new technologies to identify motion-sensitive neurons at multiple levels of the visual system. These technologies allow them to explain the interplay between nature (genetics) and nurture (experience) in the neurons' development. Joshua Sanes, whose research introduced new ways to image synapses as they form, finds that nature predominates in the retina. Analyzing the connections that transmit information between nerve cells, he recently extended his focus to the visual system and studies how retinal circuits assemble. At Harvard University, he is Professor of Molecular and Cellular Biology and the founding Director of the Center for Brain Science.
David Fitzpatrick, the Chief Executive Officer and Scientific Director of Max Planck Florida Institute, finds that nurture plays an important role in the cerebral cortex. Previously the James B. Duke Professor of Neurobiology at the Duke University School of Medicine, he is the founding Director of the Duke Institute for Brain Sciences. His research focuses on the functional organization and development of neural circuits in the cerebral cortex, the largest and most complex area of the brain. Visit www.germaninnovation.org for more information.