Biomedical subjects

Andrew Hollingworth

Publications and source records attributed to Andrew Hollingworth.

10 recordsLinked to original sources

PubMed2006

Scene and position specificity in visual memory for objects.

This study investigated whether and how visual representations of individual objects are bound in memory to scene context. Participants viewed a series of naturalistic scenes, and memory for the visual form of a target object in each scene was examined in a 2-alternative forced-choice test, with the distractor object either a different object token or the target object rotated in depth. In Experiments 1 and 2, object memory performance was more accurate when the test object alternatives were displayed within the original scene than when they were displayed in isolation, demonstrating object-to-scene binding. Experiment 3 tested the hypothesis that episodic scene representations are formed through the binding of object representations to scene locations. Consistent with this hypothesis, memory performance was more accurate when the test alternatives were displayed within the scene at the same position originally occupied by the target than when they were displayed at a different position.

Attention↗

PubMed2005

The relationship between online visual representation of a scene and long-term scene memory.

In 3 experiments the author investigated the relationship between the online visual representation of natural scenes and long-term visual memory. In a change detection task, a target object either changed or remained the same from an initial image of a natural scene to a test image. Two types of changes were possible: rotation in depth, or replacement by another object from the same basic-level category. Change detection during online scene viewing was compared with change detection after delay of 1 trial (Experiments 2A and 2B) until the end of the study session (Experiment 1) or 24 hr (Experiment 3). There was little or no decline in change detection performance from online viewing to a delay of 1 trial or delay until the end of the session, and change detection remained well above chance after 24 hr. These results demonstrate that long-term memory for visual detail in a scene is robust.

Attention↗

PubMed2005

Do new objects capture attention?

The visual system relies on several heuristics to direct attention to important locations and objects. One of these mechanisms directs attention to sudden changes in the environment. Although a substantial body of research suggests that this capture of attention occurs only for the abrupt appearance of a new perceptual object, more recent evidence shows that some luminance-based transients (e.g., motion and looming) and some types of brightness change also capture attention. These findings show that new objects are not necessary for attention capture. The present study tested whether they are even sufficient. That is, does a new object attract attention because the visual system is sensitive to new objects or because it is sensitive to the transients that new objects create? In two experiments using a visual search task, new objects did not capture attention unless they created a strong local luminance transient.

Attention↗

PubMed2005

The role of visual short-term memory in empty cell localization.

Three experiments examined the visual memory representation supporting performance at long interstimulus intervals (ISIs) in an empty cell localization task. Two arrays of dots within a 4 x 4 grid were displayed briefly in succession. One grid cell did not contain a dot in either array, and the task was to localize the empty cell. In Experiment 1, we replicated previous findings of recovery to high levels of performance at long ISIs. In Experiment 2, we tested whether figural grouping in visual short-term memory (VSTM) supports long-ISI performance by manipulating the complexity of the array pattern. Pattern complexity had no effect on empty cell localization at 0-msec ISI, suggesting dependence on high-capacity visible persistence, but there was a large simple pattern advantage at long ISIs, suggesting dependence on figural grouping in VSTM. Experiment 3 demonstrated that participants typically remember the empty cells of the first array, and not the dots, for comparison with Array 2.

Humans↗

PubMed2004

Constructing visual representations of natural scenes: the roles of short- and long-term visual memory.

A "follow-the-dot" method was used to investigate the visual memory systems supporting accumulation of object information in natural scenes. Participants fixated a series of objects in each scene, following a dot cue from object to object. Memory for the visual form of a target object was then tested. Object memory was consistently superior for the two most recently fixated objects, a recency advantage indicating a visual short-term memory component to scene representation. In addition, objects examined earlier were remembered at rates well above chance, with no evidence of further forgetting when 10 objects intervened between target examination and test and only modest forgetting with 402 intervening objects. This robust prerecency performance indicates a visual long-term memory component to scene representation.

Cognition↗

PubMed2004

Sustained change blindness to incremental scene rotation: a dissociation between explicit change detection and visual memory.

In a change detection paradigm, the global orientation of a natural scene was incrementally changed in 1 degree intervals. In Experiments 1 and 2, participants demonstrated sustained change blindness to incremental rotation, often coming to consider a significantly different scene viewpoint as an unchanged continuation of the original view. Experiment 3 showed that participants who failed to detect the incremental rotation nevertheless reliably detected a single-step rotation back to the initial view. Together, these results demonstrate an important dissociation between explicit change detection and visual memory. Following a change, visual memory is updated to reflect the changed state of the environment, even if the change was not detected.

Humans↗

PubMed2003

Failures of retrieval and comparison constrain change detection in natural scenes.

In a change detection paradigm, a target object in a natural scene either rotated in depth, was replaced by another object token, or remained the same. Change detection performance was reliably higher when a target postcue allowed participants to restrict retrieval and comparison processes to the target object (Experiment 1). Change detection performance remained excellent when the target object was not attended at change (Experiment 2) and when a concurrent verbal working memory load minimized the possibility of verbal encoding (Experiment 3). Together, these data demonstrate that visual representations accumulate in memory from attended objects as the eyes and attention are oriented within a scene and that change blindness derives, at least in part, from retrieval and comparison failure.

Adult↗

PubMed2003

Global transsaccadic change blindness during scene perception.

Each time the eyes are spatially reoriented via a saccadic eye movement, the image falling on the retina changes. How visually specific are the representations that are functional across saccades during active scene perception? This question was investigated with a saccade-contingent display-change paradigm in which pictures of complex real-world scenes were globally changed in real time during eye movements. The global changes were effected by presenting each scene as an alternating set of scene strips and occluding gray bars, and by reversing the strips and bars during specific saccades. The results from two experiments demonstrated a global transsaccadic change-blindness effect, suggesting that point-by-point visual representations are not functional across saccades during complex scene perception.

Adult↗

PubMed2003

Eye movements and visual memory: detecting changes to saccade targets in scenes.

Saccade-contingent change detection provides a powerful tool for investigating scene representation and scene memory. In the present study, critical objects presented within color images of naturalistic scenes were changed during a saccade toward or away from the target. During the saccade,the critical object was changed to another object type, to a visually different token of the same object type, or was deleted from the scene. There were three main results. First, the deletion of a saccade target was special: Detection performance for saccade target deletions was very good, and this level of performance did not decline with the amplitude of the saccade. In contrast, detection of type and token changes at the saccade target, and of all changes including deletions at a location that had just been fixated but was not the saccade target, decreased as the amplitude of the saccade increased. Second, detection performance for type and token changes, both when the changing object was the target of the saccade and when the object had just been fixated but was not the saccade target, was well above chance. Third, mean gaze durations were reliably elevated for those trials in which the change was not overtly detected. The results suggest that the presence of the saccade target plays a special role in trassaccadic integration, and together with other recent findings, suggest more generally that a relatively rich scene representation is retained across saccades and stored in visual memory.

Fixation, Ocular↗

PubMed2003

Testing a conceptual locus for the inconsistent object change detection advantage in real-world scenes.

Changes to objects that are inconsistent with the scene in which they appear are detected more accurately than changes to consistent objects. In three experiments, we tested whether this inconsistent object advantage derives from the differential retention of conceptual codes generated from a brief view of a real-world scene in accordance with a conceptual short-term memory (CSTM) hypothesis. A scene was presented for 250 msec, followed by a brief mask and a test scene in which a target object was either changed or not changed. In Experiment 1, changes that altered conceptual content (object deletion) were contrasted with visual changes (left-right orientation changes). In Experiment 2, the duration of the mask was manipulated to vary the amount of time available for conceptual consolidation of the initial scene. In Experiment 3, the type of mask was manipulated: Either a meaningless pattern mask or a meaningful, and thus conceptually disruptive, scene was shown. The inconsistent object advantage was obtained in each experiment, yet in none was it modulated in the direction predicted by the CSTM hypothesis. Instead, the inconsistent object advantage is likely to be caused by contextual influence on memory for visual object representations.

Discrimination, Psychological↗