Do inferences drawn from object properties influence saccade planning and perceptual updating?

• Applicant: Emma Stewart, Ph.D.
• Subject Area: Biological Psychology and Cognitive Neuroscience
• Term: since 2021
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 460533638

Our visual world is composed of complex objects, with a near-infinite variety of shapes, surface features, and materials. Humans can make sophisticated inferences about objects’ physical properties based their visual features. The overarching goal of the research program is to determine how inferences about object properties guide behaviour and eye movements. When completing a specific task, some objects, or object features, will be more relevant or useful for the task than others. For example, if you want to find an object to weigh down a piece of paper on a windy day you will need infer the density or weight of potential objects rather than their gloss or colour, to determine which object is the most useful, or has the highest utility, for the task. The first goal of this proposal is to determine whether people can infer the utility of an object, based on its features. Due to the eye’s resolution limitations, when searching for an object, information must be sampled from the world using sequences of rapid eye-movements called saccades. Studies into saccade-planning strategies typically use low-level features (e.g., orientation, colour), or high-level object category labels (e.g., car, duck) as predictors for where people fixate. In daily life, however, it may be more common that people have to look for an object that is the most suitable for a task based on its material properties, for example, “I need to find something hard and pointy to get the sim card out of my smartphone.” In this case inferences about the utility of an object based on its material properties should guide visual search behaviour. The second goal of this proposal is to investigate how inferences about object utility influence saccade planning. The world, however, is not static: objects can move and transform, and these changes will often occur at non-fixated, peripheral locations. The limitations of peripheral awareness are a matter of debate, and it is unclear to what extent visual awareness may rely on the representation of an object at the time it was fixated and viewed with high-resolution foveal vision, compared to a more recent, but less reliable, peripherally-viewed representation of the object. The third goal of this proposal is to determine how peripherally-viewed object representations are updated, and the circumstances under which peripheral changes reach conscious awareness.

• DFG Programme: Research Grants
• International Connection: United Kingdom, USA
• Cooperation Partners: Casimir Ludwig, Ph.D.; Dr. Ruth Rosenholtz