Going Beyond the Information Given: Seeing versus Seeing as

Variations in how we interpret ambiguous figures indicate that how a visual stimulus is perceived is determined by both its ‘objective’ visual pattern and the particular attitude we adopt towards it, ie what we see the stimulus as (Chambers and Reisberg, 1992 Cognitive Psychology 24 145 – 174). We report two experiments in which (i) ambiguous figures and (ii) natural scenes have been used to examine the relationship between how an image is perceived and what that image means to an observer.

In experiment 1 we used ‘invertible figures’ (images which when inverted portray different objects) to test two groups, (i) upright, and (ii) inverted orientation, on a recognition task involving distorted versions of the original stimulus. We found systematic differences between the two groups such that the meaning attributed to the original image determined how it was remembered. In experiment 2 we asked how prior experience affects perception. We measured rock-climbers' and non-rock-climbers' thresholds for detecting (i) non-meaningful visual pattern changes (surface changes), and (ii) meaningful changes in terms of climber affordances (deep changes). We found that climbers had lower thresholds for detecting deep changes and higher thresholds for detecting surface changes, compared with non-climbers. In contrast with the explanation based on the incomplete mental image (Chambers and Reisberg, loc. cit.), we propose that such differences are due to differences in attitude adopted towards the original stimulus, and these in turn determine what types of change can be discerned. In other words, what is important is not what is seen but how it is seen.