Perceiving the mean: A study investigating whether the low-level visual cue spatial frequency adds to the computation of higher-level ensemble coding.

Abstract

Ensemble coding enables humans to quickly assess mean properties of visual cues. Researchers discriminate between low-level ensemble coding, enabling humans to quickly assess motion, direction, speed, colour, hue, facial expression, orientation, family resemblance or size of objects in an ensemble, and higher-level ensemble coding which enables humans to quickly assess the mean emotional state or gaze of groups of people. The mystery whether higher-level ensemble coding has a computational basis in low-level visual cues remains. There seems to be ample evidence suggesting spatial frequency playing a role in decoding emotional states. In this thesis it was investigated whether the low-level cue spatial frequency added to the computation of higher-level ensembles. Analyses showed no evidence to this effect suggesting high-level ensemble coding is primarily a feature based on holistic face perception.