The Study Of Brain Mechanism On Motion-in-depth

Motion-in-depth (MID) is an important issue in study of visual motion perception. For animal, it is a critic problem to observer's survival and life in judging whether a looming object be dangerous and computing accurately when the looming object arrives, i.e. computing time-to-collision (TTC) exactly as soon as possible. Although there were many good works on animal electrophysiological studies, there was no reported mature brain mechanism model with significant physiological meanings and be consistent with the neurons characteristics. For human, to investigate how the brain processes the visual information of this motion and how it informs the motion system for escaping the impending danger object is also a meaningful project. Modern advanced neuroimaging techniques such as positron emission computerized topography (PET),functional magnetic resonance imaging (fMRI),electroencephalogram (EEG) and magnetoencephalography (MEG) provide some answers to questions in motion perception. But as a current important and hot issue, there are still many problems to be solved.This paper descibes deeply and detaily the novel studys on brain mechanism of MID course in many aspects in cognitive neural science, including mathematical model, event-related potential (ERP) spatio-temporal analysis and so on. Our main works and achievements are follows:1. The study on animal's brain mechanism on detecting collision courseIt expatiate the animal's (pigeon) brain mechanism on detecting collision course from model field simulated by neural network method with good results. The simple and convenient property of the model is consistent with animal's simple response principal. And the good representations of the model on physiology, robustness, extensibility and applicability manifest it might be a very potential and reliable brain mechanism on explaining the whole visual information process on pigeon brain from initial retinal imaging to obtaining final accurate TTC information.2. The study on human's brain mechanism on percepting MID courseThrough an experimental paradigm more close to human's visual experience, combined with human's ERP and fMRI data, we study the human's brain mechanism on MID course systematically. Multiple spatial and temporal analysis methods are adopted to analyse the ERP signals. The results indicate that the perception of MID and motion-in-plane (MIP) is different, and the MID ERPs are strongly affected by the motion direction, impending object's size and moving speed. The perception of MID activates three main brain areas and showes five main temporal components. This paper discusses the significances and roles of these spatio-temporal dynamic responses on the perception of MID in detail. Basing on these achievements, we propose a simple multi-areas synchronous integrated model on interpreting how the visual information processed in the perception of MID.3. The study on integration of brain informationFrom the viewpoint of integration of brain information, this paper explores the visual information process in MID course on animal and human by participating in the study of different animal's and human's brain mechanism to propose more rational brain mechanism solution. The proposed spatio-temporal integrated model on animal's detecting collision course and the multi-areas synchronous integrated model on human's percepting MID course have definite physiological meanings and might be very possible visual brain mechanisms on interpreting the visual information process in the perception of MID. And they might be expected to apply in visual system on artificial intelligent robotics to achieve the perception of MID and avoid collision by bionics manner.