Memory for relational information across eye movements

Abstract

Structural descriptions are hierarchical representations of a visual stimulus in terms of its parts and their relations, Previous research in which the retention of parts was examined has shown that structural descriptions can be used to represent information in transsaccadic memory, In three experiments, this idea was tested further by examining whether relational information is also maintained across saccades. Experiment 1, in which a same/different comparison task was used, showed that both part and relation information are retained across fixations in the same manner as within a fixation. Experiment 2 showed that such retention is impervious to instruction. Finally, Experiment 3, in which a new set of stimuli was used, demonstrated that both coordinate and categorical relations are maintained across saccades, The results indicate that structural descriptions can be used to represent information in transsaccadic memory in a manner similar to their use in visual short-term memory.The visual world extends before us in all directions, but our eyes only pick up information from a limited portion of this expanse at anyone time. To accommodate for this limitation, we make eye movements, in order to select particular objects or regions ofinterest. Periods oftime in which the eyes are in motion are called saccades, and the intake of visual information during saccades is actively suppressed by the visual system (see, e.g., Matin, 1974). This restricts visual information input to periods of time in which the eyes are relatively still, called fixations. Despite this discontinuous input, we perceive the world as familiar (e.g., not filled with novel to-be-identified objects with each fixation) and stable (e.g., objects do not appear to move, even though their retinal positions change). How this perception of a stable visual world is achieved is a classical question in visual perception.One approach to addressing this issue has been to examine the retention of information in transsaccadic memory (e.g., Irwin, 1991), a memory store that preserves information from one fixation for use during subsequent fixations. The general methodology used to examine transsaccadic memory employs the saccade-contingent display change technique, pioneered by McConkie and Rayner (1975), which isolates the presentation of a stimulus to a single fixation. For example, a figure is presented during a single eye fixation, and a saccade is elicited; upon the detection of the saccade onset, the first figure is erased, and a second figure is presented during the next eye fixation. The subject's task usually involves a comparative judgment about the two figures. This task requires transsaccadic memory, because the first figure is no longer present when the second figure appears (Irwin, 1992a).Using such a paradigm, research has demonstrated that visual information is retained in transsaccadic memory (see Irwin, 1992b;Pollatsek & Rayner, 1992, for reviews). For example, using a picture-naming paradigm, Pollatsek, Rayner, and Collins (1984) presented s...

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Transsaccadic representation of layout: What is the time course of boundary extension?

“…In general, results suggest that representations of structural descriptions of objects are retained (CarlsonRadvansky & Irwin, 1995;Carlson-Radvansky, 1999;Verfaillie & De Graef, 2000;Verfaillie, De Troy, & Van Rensbergen, 1994), but there is also evidence for retention of specific visual information (object orientation: Henderson & Siefert, 1999, 2001; but not detailed object contours: Henderson, 1997). …”

Transsaccadic memory of position and form

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