Holly Lockhart

Brock University · Department of Psychology

Although recent evidence suggests that visual short-term memory (VSTM) is a continuous resource, little is known about how flexibly this resource can be allocated. Previous studies using probabilistic cues to indicate two different levels of probe probability have found that response precision can be predicted according to a continuous allocation o...

Visual working memory (VWM) resources have been shown to be flexibly distributed according to item priority. This flexible allocation of resources may depend on attentional control, an executive function known to decline with age. In this study, we sought to determine how age differences in attentional control affect VWM performance when attention...

Visual working memory is a brief, capacity-limited store of visual information that is involved in a large number of cognitive functions. To guide one’s behavior effectively, one must efficiently allocate these limited memory resources across memory items. Previous research has suggested that items are either stored in memory or completely blocked...

Attention regulates visual working memory (VWM) performance by determining how its resources are distributed among encoded information. During encoding, this process is both flexible and strategic: Resources are unequally allocated to items based on the probability that each will be probed for memory recall. Here we assessed whether VWM resources c...

There is a limit to how much information can be stored in visual working memory (VWM). Previous models of this limitation have focused on the effects of VWM load, finding that behavioral recall of memory items becomes worse as load increases. Similarly, ERP studies examining the neural markers of VWM have focused primarily on load effects, explorin...

Efficiently allocating capacity-limited cognitive resources is critical to guiding behavior effectively. Although previous research has suggested that distractors are blocked from memory access, recent work proposes a more flexible attentional filter that acts based on item priority. Here, we investigated the electrophysiological correlates of flex...

There is a limit to how much information can be stored in visual working memory (VWM). Previous models of this limitation have focused on the effects of VWM load, finding that behavioral recall of memory items becomes worse as load increases. Similarly, ERP studies examining the neural markers of VWM have focused primarily on load effects, explorin...

Although recent evidence suggests that visual short-term memory is a continuous resource, little is known about how flexibly this resource can be allocated. The current study used a continuous report procedure and attentional prioritization via probabilistic spatial cues to address three unknown properties of a flexible continuous resource. The fir...

Working memory (WM) is impaired following sleep loss and may be improved after a nap. The goal of the current study was to better understand sleep-related WM enhancement by: 1) employing a WM task that assesses the ability to hold and report visual representations as well as the fidelity of the reports on a fine scale, 2) investigating neurophysiol...

Working memory (WM) is impaired following sleep loss and may be improved after a nap. The goal of the current study was to better understand sleep-related WM enhancement by: (1) employing a WM task that assesses the ability to hold and report visual representations as well as the fidelity of the reports on a fine scale, (2) investigating neurophysi...

Participants reported the feature of two objects from a set of six coloured squares when either both were high priority objects, both were low-priority objects or one was high and one was low priority. -abstract published in the Journal of Vision September issue.

Though it is clear that it is impossible to store an unlimited amount of information in visual working memory (VWM), the limiting mechanisms remain elusive. While several models of VWM limitations exist, these typically characterize changes in performance as a function of the number of to-be-remembered items. Here, we examine whether changes in spa...

Our limited capacity for processing and filtering relevant information often results in binding errors when a target is presented in a crowded display. It was recently suggested that substitution of features between target and distractors might be the consequence of a failure to individuate the target during processing and that the N2pc event-relat...

Visual working memory (VWM) is a limited resource, which may be distributed discretely or continuously, as predicted by opposing theoretical models. When presented with distracting information, it is most efficient to ignore or minimally process it. However, in many situations some items are more relevant than others and the target/distractor disti...

Findings from a recent EEG study by Anderson et al. (2014) support the idea that crowded visual displays prevent individuation of a target and results in the substitution of features from the distractors during target processing. An alternative explanation for this phenomenon, also known as binding errors, suggests that this misattribution may be t...

There is a great deal of debate over the number and quality of items that can be represented in visual working memory (VWM). One theoretical model of VWM predicts that working memory has a discrete capacity limit of three to four items; while other models predict that VWM is a limited pool of resources that can be distributed fluidly. However, the...