Publications by authors named "Amanda E van Lamsweerde"

Over the last several years, the study of working memory (WM) for simple visual features (e.g., colors, orientations) has been dominated by perspectives that assume items in WM are stored independently of one another.

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Background: Although self-help strategies to improve sleep are widely accessible, little is known about the ways in which individuals interact with these resources and the extent to which people are successful at improving their own sleep based on sleep health recommendations. The present study developed a lab-based model of self-help behavior by observing the development of sleep health improvement plans (SHIPs) and examining factors that may influence SHIP development.

Method: Sixty healthy, young adults were identified as poor sleepers during one week of actigraphy baseline and recruited to develop and implement a SHIP.

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Face animacy perception is categorical: Gradual changes in the real/artificial appearance of a face lead to nonlinear behavioral responses. Neural markers of face processing are also sensitive to face animacy, further suggesting that these are meaningful perceptual categories. Artificial faces also appear to be an "out-group" relative to real faces such that behavioral markers of expert-level processing are less evident with artificial faces than real ones.

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Face processing mechanisms are tuned to specific low-level features including mid-range spatial frequencies and horizontal orientation energy. Behaviorally, adult observers are more effective at face recognition tasks when these information channels are available. Neural responses to face images also reflect these information biases: Face-sensitive ERP components respond preferentially to face images that contain horizontal orientation energy.

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Studies of change detection have shown that changing the task-irrelevant features of remembered objects impairs change detection for task-relevant features, a phenomenon known as the irrelevant change effect. Although this effect is pronounced at short study-test intervals, it is eliminated at longer delays. This has prompted the proposal that although all features of attended objects are initially stored together in visual working memory (VWM), top-down control can be used to suppress task-irrelevant features over time.

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Attention allocation determines the information that is encoded into memory. Can participants learn to optimally allocate attention based on what types of information are most likely to change? The current study examined whether participants could incidentally learn that changes to either high spatial frequency (HSF) or low spatial frequency (LSF) Gabor patches were more probable and to use this incidentally learned probability information to bias attention during encoding. Participants detected changes in orientation in arrays of 6 Gabor patches: 3 HSF and 3 LSF.

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Maintaining visual working memory (VWM) representations recruits a network of brain regions, including the frontal, posterior parietal, and occipital cortices; however, it is unclear to what extent the occipital cortex is engaged in VWM after sensory encoding is completed. Noninvasive brain stimulation data show that stimulation of this region can affect working memory (WM) during the early consolidation time period, but it remains unclear whether it does so by influencing the number of items that are stored or their precision. In this study, we investigated whether single-pulse transcranial magnetic stimulation (spTMS) to the occipital cortex during VWM consolidation affects the quantity or quality of VWM representations.

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There is considerable debate regarding the ability to trade mnemonic precision for capacity in working memory (WM), with some studies reporting evidence consistent with such a trade-off and others suggesting it may not be possible. The majority of studies addressing this question have utilized a standard approach to analyzing continuous recall data in which individual-subject data from each experimental condition is fitted with a probabilistic model of choice. Estimated parameter values related to different aspects of WM (e.

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The limited capacity of visual working memory (VWM) can be maximized by combining multiple features into a single representation through grouping principles such as connection, proximity, and similarity. In this study, we sought to understand how VWM organizes information by investigating how connection and similarity cues are used either alone or in the presence of another grouping cue. Furthermore, we examined whether the use of one cue over another is within volitional control.

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When briefly presented with global and local visual information, individuals report global information more quickly and more accurately than local information, a phenomenon known as the global precedence effect (GPE; Navon, 1977). We investigated whether a bias toward global information persists in visual working memory (VWM) and whether the VWM representations for global and local features include information bound to their hierarchical levels and to each other. Navon figures, in which a larger (global) letter is composed of smaller (local) letters, were presented, and participants performed a change detection task that required participants to remember features only (either a global or local letter changed to a new identity); features bound to their hierarchical levels (the global and local letters within an object swapped levels); or features bound to each other within an object (2 letters from the same level swapped between objects).

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In this study, we investigated whether the ability to learn probability information is affected by the type of representation held in visual working memory. Across 4 experiments, participants detected changes to displays of coloured shapes. While participants detected changes in 1 dimension (e.

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The ability to remember feature bindings is an important measure of the ability to maintain objects in working memory (WM). In this study, we investigated whether both object- and feature-based representations are maintained in WM. Specifically, we tested the hypotheses that retaining a greater number of feature representations (i.

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Responses are quicker to predictable stimuli than if the time and place of appearance is uncertain. Studies that manipulate target predictability often involve overt cues to speed up response times. However, less is known about whether individuals will exhibit faster response times when target predictability is embedded within the inter-trial relationships.

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Statistical properties in the visual environment can be used to improve performance on visual working memory (VWM) tasks. The current study examined the ability to incidentally learn that a change is more likely to occur to a particular feature dimension (shape, color, or location) and use this information to improve change detection performance for that dimension (the change probability effect). Participants completed a change detection task in which one change type was more probable than others.

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In visual change detection tasks, providing a cue to the change location concurrent with the test image (post-cue) can improve performance, suggesting that, without a cue, not all encoded representations are automatically accessed. Our studies examined the possibility that post-cues can encourage the retrieval of representations stored in long-term memory (LTM). Participants detected changes in images composed of familiar objects.

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