See What I’m Saying? Expertise and Verbalisation in Perception and Imagery of Complex Scenes

Abstract

How does describing a previously viewed picture affect our memory for it? Does verbalisation affect our eye movements even when the picture has disappeared? When viewing a photograph, the sequences of eye movements we make (‘scanpaths’) are influenced by both bottom-up visual saliency and top-down cognitive knowledge. Recognition memory is enhanced and the similarity of scanpaths at encoding and recognition is greater for domain-specific pictures. A similarity in scanpaths is also observed during imagery but to a greatly reduced degree. This study explored whether scanpath similarity could be improved by verbalising one’s memory of the picture and whether the previously observed domain-specific advantage was still present when no bottom-up information was available. Specialists and controls were shown a set of photographs, and after each one had to either visualise it or describe it from memory. The stimuli were complex scenes, half of which contained a domain-specific object. Recognition accuracy was increased by post-stimulus verbalisation, and specialists demonstrated an advantage for stimuli that contained domain-relevant information. Saliency influenced both verbal feedback and eye movements but was moderated by domain expertise. Scanpaths were more similar when pictures were described compared to when imagined, and specialists produced more similar scanpaths when describing domain-specific pictures, compared to control pictures and control participants.