Towards a Theory of Visual Concealment

Abstract

The goal of this dissertation is to take initial steps towards understanding concealment behaviour and ultimately developing a theory of visual concealment. Since there are relatively few studies of concealment in the literature and given the natural relationship between search and concealment, five strategies used in the development of traditional visual search theory and scene-based search theory were applied to the study of concealment. These strategies are: 1) establish a methodology, 2) identify dimensions, 3) categorize dimensions, 4) prioritize dimensions, and 5) integrate results into a theoretical framework that may involve inferences about the mechanisms involved. In Chapter 2, participants placed target objects within luggage in locations that were easy or hard to find (i.e., the placement task). Participants’ subjective reports of their thought processes and strategies were analyzed to identify dimensions that are important during concealment in real-world settings. Once a list of dimensions was generated, the dimensions were then categorized into three categories: Stimulus Properties dimensions such as visual similarity, Embodiment dimensions such as confrontation, and Higher Order dimensions such as schema. In Chapter 3, the dimensions uncovered in Chapter 2 were used in a forced-choice task, and participants’ choices were evaluated to determine whether the dimensions affected hiding behaviour. To further develop the methodological techniques available to study concealment behaviour and to examine the generalizability of previous findings, in Chapter 4, the placement task was used in another context – an office environment – and the locations chosen by participants to make objects easy or hard to find were coded on relevant dimensions. In Chapter 5, an initial attempt was made to prioritize the dimensions. The forced-choice task was used in a new way to explore the relative importance of the dimensions by examining which dimensions participants chose to use over other dimensions. Finally in the General Discussion in Chapter 6, an attempt was made to integrate available results and previous theories and to make inferences about the mechanisms involved in visual concealment. Methodological considerations and future directions for the study of visual concealment are also discussed.