The role of salience on crowding and visual search in the context of synaesthesia

Abstract

Visual crowding is a phenomenon in which the identification of visual stimuli is impaired by nearby directions. it occurs both for simple stimuli (oriented lines) and for more complex forms. The literature on crowding is reviewed, along with relevant literature on visual search and stimulus salience. Experiments are reported to test the idea that visually salient stimuli can escape, in part from crowding. The salience of stimuli was manipulated by varying their motion direction, colour, or temporal frequency relative to dis tractors. Salience was also measured independently of crowding using the pop out paradigm in visual search. Results showed that stimuli independently defined as salient did escape, in part, from crowding. A following experiment attempted to see whether the same would be true for the subjective colours experienced by synaesthetes