Quantifying variation in the temporal resolution of the visual system

Abstract

Temporal processing, the regular updating of visual information over time, is an integral part of visual perception. It contributes to motion perception, allows for the perception of environmental changes and, depending on the situation, may determine whether one can see anything at all. A higher temporal resolution means that the visual system processes information on a smaller timescale, and thus provides access to potentially more visual information per timeframe. High visual processing rates may have considerable advantages in many situations, but fast sensory processing is metabolically costly. Additionally, physical constraints give rise to a trade-off between high temporal- and high spatial processing. Within the bounds set by these limitations, visual temporal resolution is found to vary greatly in the animal kingdom. This variation is likely driven by specific visual requirements for different species depending on their ecological niche. For temporal resolution to be influenced by different selection pressures, a certain amount of variation must exist not only among species, but also among individuals within a species. How large this variation may be, and which processes may dictate different rates of temporal resolution within an individual are currently unclear. Moreover, the possible selective pressures acting on this trait are relatively unexplored, and it is not clear how different ecological settings may influence temporal resolution. In this thesis, I use ecological principles, psychophysical experiments, neuroscience and sports science to investigate variability in visual temporal resolution on multiple levels. I assess variation in visual processing rates both among and within species, and among and within individuals, and explore how this variation may be linked with specific ecological settings.