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Behavioral and neuroscience research on boundary extension (false memory beyond the edges of a view of a scene) has provided new insights into the constructive nature of scene representation, and motivates questions about development. Early research with children (as young as 6-7 years) was consistent with boundary extension, but relied on an analysis of spatial errors in drawings which are open to alternative explanations (e.g. drawing ability). Experiment 1 replicated and extended prior drawing results with 4-5-year-olds and adults. In Experiment 2, a new, forced-choice immediate recognition memory test was implemented with the same children. On each trial, a card (photograph of a simple scene) was immediately replaced by a test card (identical view and either a closer or more wide-angle view) and participants indicated which one matched the original view. Error patterns supported boundary extension; identical photographs were more frequently rejected when the closer view was the original view, than vice versa. This asymmetry was not attributable to a selection bias (guessing tasks; Experiments 3-5). In Experiment 4, working memory load was increased by presenting more expansive views of more complex scenes. Again, children exhibited boundary extension, but now adults did not, unless stimulus duration was reduced to 5 s (limiting time to implement strategies; Experiment 5). We propose that like adults, children interpret photographs as views of places in the world; they extrapolate the anticipated continuation of the scene beyond the view and misattribute it to having been seen. Developmental differences in source attribution decision processes provide an explanation for the age-related differences observed.

How rapidly does boundary extension occur? Across experiments, trials included a 3-scene sequence (325 ms/picture), masked interval, and repetition of 1 scene. The repetition was the same view or differed (more close-up or wide angle). Observers rated the repetition as same as, closer than, or more wide angle than the original view on a 5-point scale. Masked intervals were 100, 250, 625, or 1,000 ms in Experiment 1 and 42, 100, or 250 ms in Experiments 2 and 3. Boundary extension occurred in all cases: Identical views were rated as too "close-up," and distractor views elicited the rating asymmetry typical of boundary extension (wider angle distractors were rated as being more similar to the original than were closer up distractors). Most important, boundary extension was evident when only a 42-ms mask separated the original and test views. Experiments 1 and 3 included conditions eliciting a gaze shift prior to the rating test; this did not eliminate boundary extension. Results show that boundary extension is available soon enough and is robust enough to play an on-line role in view integration, perhaps supporting incorporation of views within a larger spatial framework. (Contains 7 figures and 1 footnote.)

This investigation examined whether infants display "boundary extension"--a tendency to remember more of a visual scene than was presented. Three- to 7-month-olds were familiarized with a photograph of a visual scene, and tested with wide-angle versus close-up views of the scene. Infants preferred the close-up, indicating that they perceived the wide angle (the one consistent with boundary extension) as more familiar. Converging experiments showed that: (a) infants did not spontaneously prefer the close-up, (b) adults did not judge the wide angle to be more similar to the familiarization stimulus, and (c) infants spontaneously preferred the close-up when the photographs depicted outline objects without backgrounds. The findings suggest that infants anticipate information that lies beyond the borders of a scene view.

Viewers who study photographs of scenes tend to remember having seen beyond the boundaries of the view ["boundary extension"; J. Exp. Psychol. Learn. Mem. Cogn. 15 (1989) 179]. Is this a fundamental aspect of scene representation? Forty undergraduates explored bounded regions of six common (3D) scenes, visually or haptically (while blindfolded) and then the delimiting borders were removed. Minutes later they reconstructed boundary placement. Boundary extension occurred: mean areas were increased by 53% (vision) and by 17% (haptics). A deaf-and-blind woman (KC) haptically explored the same regions. Although a ''haptic expert'', she too remembered having explored beyond the boundaries, with performance similar to that of the blindfolded-sighted. Boundary extension appears to be a fundamental aspect of spatial cognition. Possibly constrained by the ''scope'' of the input modality (vision is greater than haptics), this anticipatory spatial representation may facilitate integration of successively perceived regions of the world irrespective of modality and the perceiver's sensory history.

How rapidly does boundary extension occur? Across experiments, trials included a 3-scene sequence (325 ms/picture), masked interval, and repetition of 1 scene. The repetition was the same view or differed (more close-up or wide angle). Observers rated the repetition as same as, closer than, or more wide angle than the original view on a 5-point scale. Masked intervals were 100, 250, 625, or 1,000 ms in Experiment 1 and 42, 100, or 250 ms in Experiments 2 and 3. Boundary extension occurred in all cases: Identical views were rated as too 'close-up,' and distractor views elicited the rating asymmetry typical of boundary extension (wider angle distractors were rated as being more similar to the original than were closer up distractors). Most important, boundary extension was evident when only a 42-ms mask separated the original and test views. Experiments 1 and 3 included conditions eliciting a gaze shift prior to the rating test; this did not eliminate boundary extension. Results show that boundary extension is available soon enough and is robust enough to play an on-line role in view integration, perhaps supporting incorporation of views within a larger spatial framework. Keywords: scene perception, transsaccadic memory, visuospatial memory, boundary extension, spatial cognition

What distinguishes scenes from nonscenes? Photographs of objects on both naturalistic and blank backgrounds yielded boundary extension (BE: memory for unseen spatial expanse outside the picture's boundaries). However, line-drawn objects on blank backgrounds did not (Experiment 1). Perhaps the blank background was construed as depicting a real-world surface in the photograph condition but was construed as depicting nothing in the line-drawn condition. To change background construal, the authors used objects cut out of photographs; these were placed on blank backgrounds while viewers watched (Experiments 2 and 3). BE was eliminated. The authors propose that amodal continuation is a fundamental aspect of scene perception. However, not all pictures are scenes--only pictures construed as depicting a truncated view of a continuous world.

Two experiments tested the predictions of an integrative buffer model of visual processing, regarding the illusory conjunction of components of rapidly presented displays. Color pictures of objects were presented at a rate of 9/s, in the same spatial location. Experiment 1 used a modified report procedure to test the hypothesis that Stroop-like response competition, during naming, not a perceptual error, resulted in the high confidence "illusory conjunctions" reported in previous research. Subjects were provided with the naem of a picture in advance and reported "yes" or"no" to indicate if that picture was the one in the frame. Contrary to the response competition hypothesis, high confidence errors occured frequently under these conditions. Experiment 2 tested the hypothesis that the direction of migration (preceding or following picture) is the result of a difference in the sequential allocation of attention to the frame first or to its "host" picture first on different trials. As predicted by the integrative buffer model, subjects were faster in detecting the frame when they confidently reported it around the preceding picture than around the followuing picture in the sequence, and reaction times associated with correct reports fell between the two.

Viewers remember seeing more of a scene than was actually depicted in a photograph, a phenomenon called boundary extension (H. Intraub & M. Richardson, 1989). We tested whether prior warning would eliminate this distortion, by having 81 Ss view 12 photographs of simple scenes for 15 s each after receiving 1 of 3 encoding instructions. All subjects were told to remember each picture in detail. Control Ss received no additional information. Test-informed Ss received prior warning about the type of tests. Demo Ss experienced a demonstration of the phenomenon and were instructed to guard against it. After presentation, a drawing task and a boundary recognition test were administered. Prior warning sometimes reduced, but never eliminated, boundary extension. We suggest the phenomenon reflects activation of scene expectations during perception.

Ss tend to remember close-up photographs as having had extended boundaries (Intraub & Richardson, 1989). Three alternate explanations were tested: object completion, distortion toward a perceptual schema, and normalization toward a prototypic view. In three experiments, 55-130 undergraduates viewed 16 close-up, prototypic or wide-angle views of objects for 15 s each. Immediately or 48 hr later, they rated test pictures on a 5-point scale as 'same,' 'closer up,' or 'father away.' Results ruled out object completion because boundary extension occurred when the picture contained no incomplete objects. Immediate tests supported the perceptual schema hypothesis because all unidirectional distortions involved boundary extension. Delayed tests were more suggestive of a memory schema effect because wide-angle pictures restriction. A two-component model of picture processing is proposed.

Behavioral and neuroscience research on boundary extension (false memory beyond the edges of a view of a scene) has provided new insights into the constructive nature of scene representation, and motivates questions about development. Early research with children (as young as 6-7 years) was consistent with boundary extension, but relied on an analysis of spatial errors in drawings which are open to alternative explanations (e.g. drawing ability). Experiment 1 replicated and extended prior drawing results with 4-5-year-olds and adults. In Experiment 2, a new, forced-choice immediate recognition memory test was implemented with the same children. On each trial, a card (photograph of a simple scene) was immediately replaced by a test card (identical view and either a closer or more wide-angle view) and participants indicated which one matched the original view. Error patterns supported boundary extension; identical photographs were more frequently rejected when the closer view was the original view, than vice versa. This asymmetry was not attributable to a selection bias (guessing tasks; Experiments 3-5). In Experiment 4, working memory load was increased by presenting more expansive views of more complex scenes. Again, children exhibited boundary extension, but now adults did not, unless stimulus duration was reduced to 5 s (limiting time to implement strategies; Experiment 5). We propose that like adults, children interpret photographs as views of places in the world; they extrapolate the anticipated continuation of the scene beyond the view and misattribute it to having been seen. Developmental differences in source attribution decision processes provide an explanation for the age-related differences observed. [ABSTRACT FROM AUTHOR]

Shepard's (1994) choice of kinematic geometry to support his theory is questioned by Todorovic, Schwartz, and Hecht. His theoretical framework, however, can be applied to another domain that may be less susceptible to some of their concerns. The domain is the representation of spatial layout. [HECHT; SCHWARTZ; SHEPARD; TODOROVIC]

'Temporal migration' describes a situation in which subjects viewing rapidly presented stimuli (e.g., 9-20 items/s) confidently report a target element as having been presented in the same display as a previous or following stimulus in the sequence. Four experiments tested a short-term buffer model of this phenomenon. Experiments 1 and 4 tested the hypothesis that subjects' errors are due to the demands of the verbal report procedure rather than to perceptual integration. In Experiment 1, 12 color objects were presented at a rate of 9/s. Prior to each sequence, an object was named and subjects responded 'yes' or 'no' to indicate whether the target element (a black frame) occurred with that object. Consistent with the perceptual hypothesis, the yes/no procedure yielded the same results as the verbal report procedure. Experiment 2 tested the hypothesis that the direction of migration depends on 'frame' detection time. Results showed that reaction time to frame detection was significantly faster in trials in which subjects reported the frame on a preceding rather than a following picture. Experiments 3 and 4 used the standard naming procedure and the yes/no procedure to test temporal migration using more complex, interrelated stimuli (objects and scenes). Implications for the use of the temporal migration effect to study visual integration within eye fixations are discussed.

We report a picture-memory phenomenon in which subjects' recall and recognition of photographed scenes reveal a pronounced extension of the pictures' boundaries. After viewing 20 pictures for 15 each, 37 undergraduates exhibited this striking distortion; 95% of their drawings included information that had not been physically present but that would have been likely to have existed just outside the camera's field of view (Experiment 1). To determine if boundary extension is limited to recall and drawing ability, Experiment 2 tested recognition memory for boundaries. Eighty-five undergraduates rated targets and distractors on a boundary-placement scale. Subjects rated target pictures as being closer up than before and frequently mistook extended-boundary distractors as targets. Results are discussed in terms of picture comprehension and memory. In addition to its theoretical value, discovery of the phenomenon demonstrates the importance of more widespread use of open-ended tests in picture-memory methodology.