Unleashing gaze: Neuro-cognitive processes underlying gaze control and perception across free-viewing eye movements

Introduction

We constantly move our eyes to explore our surroundings. In between short periods of fixation, saccades cause drastic changes to the visual input – yet, we experience a continuous and stable world from the incessant flow of snapshots.

Perceptual Consequences

While the perceptual consequences of saccadic eye movements are manifold, experiments to study them are surprisingly similar, and lean towards a paradoxically passive investigation of active visual perception. Instead of isolated, stereotyped eye movements directed by artificial cues, everyday gaze is dynamically driven by scene statistics and internal goals.

Methodological Limitations

To genuinely understand active perception across eye movements, we need to study it under natural but still precisely controlled conditions – which so far has been hindered by methodological limitations. The transient nature of peri-saccadic phenomena requires real-time knowledge of the upcoming saccade to tailor the perceptual measurement to its predicted spatial and temporal dynamics.

Predicting Saccades

Fortunately, free-viewing saccades are not random, but guided by salient and relevant scene features. My team and I will introduce a methodology that evaluates these factors online, to predict saccades during free exploration on dynamic visual noise.

Integrating Techniques

To study active perception through gaze-contingent measures across unconstrained viewing, my approach integrates high-precision yet rigid techniques from classic vision science with more flexible but coarser methods of scene viewing research, where subtle peri-saccadic processes are traditionally not considered.

Project Goals

Combining state-of-the-art psychophysical, computational, and neuroscientific expertise, FREE-VIEW will:

1. Pioneer our understanding of actually active perception and gaze control.
2. Assess the validity of inferences drawn from atypical, instructed saccades.
3. Introduce a versatile tool for testing populations that may struggle to learn or adhere to stringent instructions, such as children, the elderly, patients, or non-human primates.