Active Vision Through Invariant Representations And Saccade Movements

This collection of recent studies spans a range of computational intelligence applications, emphasizing their application to challenging real-world problems. Covers Intelligent agent-based algorithms, Hybrid intelligent systems, Machine learning and more.

Volumes consist of the proceedings of the International Conference on Applications and Science of Artificial Neural Networks.

Every time we move our eyes, a slightly different image is recorded at the back of our eye (i.e., the retina). However, we seldom perceive this change in the visual world due to frequent eye movements or saccades. How we maintain stable perception of the world is then a critical yet complex question to understand our visual system and cognitive processes. My dissertation aims at understanding more about visual stability from three example visual functions that interact with saccades. Chapter 1 (General Introduction) briefly summarizes the relevant literature on visual stability. Chapter 2 explores the brain representations of top-down spatial attention in retinotopic (eye-centered) and spatiotopic (world-centered) reference frames across saccades. By analyzing the patterns of brain activity from fMRI scans, I found that updating spatial attention across saccades might be coded with a combination of attention “shift” and “hold” signals across different brain regions/networks. Chapter 3 focuses on how saccades affect the perception and neural representations of 3D stimulus depth. Participants passively viewed stimuli at different 3D locations, and the brain representations of vertical and depth information were assessed and compared between no-saccade blocks and saccade blocks. The results showed that in saccade blocks, despite the retinal changes in horizontal position induced by the saccades, both vertical and depth information could still be decoded in visual areas, to a similar extent as in no-saccade blocks. In contrast, little vertical or depth information could be decoded across no-saccade blocks with different eye positions in any visual areas, indicating eye-position-dependency during stable fixation. Representations of spatial locations (2D and depth) may become more tolerant of eye positions during “dynamic” saccades, perhaps due to active remapping during saccades which may encourage more stable representations of the world. Chapter 4 presents a human behavioral study focused on target localization, where participants remembered and reported the location of the target on the screen after making a saccade, with task-irrelevant nontarget objects presented alongside. The results showed that the spatial relationship between the target and nontargets was utilized for target localization; however it also biased responses spatially. The final Chapter 5 (General Discussion) discusses how these three studies together help to further understand how visual information is integrated despite changeable inputs due to eye movements.

This volume contains selected and edited papers from the 7th European Conference on Eye Movements (ECEM 7) held in Durham, UK on August 31-September 3 1993. The volume is organized as follows:- Invited Lectures, Pursuit and Co-Ordination, Saccade and Fixation Control, Oculomotor Physiology, Clinical and Medical Aspects of Eye Movements, Eye Movements and Cognition, Eye Movements and Language and finally, Displays and Applications.

How does your mind work? How does your brain give rise to your mind? These are questions that all of us have wondered about at some point in our lives, if only because everything that we know is experienced in our minds. They are also very hard questions to answer. After all, how can a mind understand itself? How can you understand something as complex as the tool that is being used to understand it? This book provides an introductory and self-contained description of some of the exciting answers to these questions that modern theories of mind and brain have recently proposed. Stephen Grossberg is broadly acknowledged to be the most important pioneer and current research leader who has, for the past 50 years, modelled how brains give rise to minds, notably how neural circuits in multiple brain regions interact together to generate psychological functions. This research has led to a unified understanding of how, where, and why our brains can consciously see, hear, feel, and know about the world, and effectively plan and act within it. The work embodies revolutionary Principia of Mind that clarify how autonomous adaptive intelligence is achieved. It provides mechanistic explanations of multiple mental disorders, including symptoms of Alzheimer's disease, autism, amnesia, and sleep disorders; biological bases of morality and religion, including why our brains are biased towards the good so that values are not purely relative; perplexing aspects of the human condition, including why many decisions are irrational and self-defeating despite evolution's selection of adaptive behaviors; and solutions to large-scale problems in machine learning, technology, and Artificial Intelligence that provide a blueprint for autonomously intelligent algorithms and robots. Because brains embody a universal developmental code, unifying insights also emerge about shared laws that are found in all living cellular tissues, from the most primitive to the most advanced, notably how the laws governing networks of interacting cells support developmental and learning processes in all species. The fundamental brain design principles of complementarity, uncertainty, and resonance that Grossberg has discovered also reflect laws of the physical world with which our brains ceaselessly interact, and which enable our brains to incrementally learn to understand those laws, thereby enabling humans to understand the world scientifically. Accessibly written, and lavishly illustrated, Conscious Mind/Resonant Brain is the magnum opus of one of the most influential scientists of the past 50 years, and will appeal to a broad readership across the sciences and humanities.

Each time the eyes are spatially reoriented via a saccadic eye movement, the image falling on the retina changes. How visually specific are the representations that are functional across saccades during active scene perception? This question was investigated with a saccade-contingent display-change paradigm in which pictures of complex real-world scenes were globally changed in real time during eye movements. The global changes were effected by presenting each scene as an alternating set of scene strips and occluding gray bars, and by reversing the strips and bars during specific saccades. The results from two experiments demonstrated a global transsaccadic change-blindness effect, suggesting that point-by-point visual representations are not functional across saccades during complex scene perception. Ahstract.