חוה מטיכן

תלמידת המחלקה לתואר שני תרצה בנושא:

A single additive mechanism predicts Lateral Facilitation effects- computational model

The goal of this study was to develop and suggest a computational model for well known visual effect termed lateral facilitation (Polat & Sagi, 1993).

Lateral facilitation is a visual effect in which a stimulus is perceived only when it is located between two collinear flankers who share similar orientation.

It was also reported that similarly oriented flankers, but with closer proximity, can lead to the opposite phenomenon, where super-threshold stimuli becomes unnoticeable, it has been termed lateral inhibition.

The mechanism underlying this lateral facilitation and inhibition phenomena is still an enigma. Over the years, some groups have tried to explain the phenomena and suggested models to predict either the psychophysics or the neurological results, but none of these models refer to the variety of the flankers' configurations.

We propose a simple but inclusive computational model which proves that a positive additive signal, generated by the flankers, can solely predict the LF effects. The model predicts the different and conflicting findings regarding the facilitation and "inhibition" aspects of the phenomenon. The model predicts both classical and recent results. We suggest that the lateral facilitation plays a role in creating an educated guess to form a continuation of gratings and textures based on the surrounding visual stimuli. We believe that understanding of the LF mechanism may shed light on additional higher cortical phenomena such as texture segmentation and contour integration.

העבודה נעשתה בהנחיית ד"ר חדוה שפיצר, הפקולטה להנדסה

ופרופ' שמואל עינב, המחלקה להנדסה ביו-רפואית, אוניברסיטת תל-אביב

ההרצאה תתקיים ביום ראשון 18.11.2012, בשעה 15:15,

בחדר 315, הבניין הרב תחומי, אוניברסיטת תל אביב