Action similarity warps visual feature space in working memory.

Visual working memory (VWM) retains representations of past visual information for future action. Yet to date, most studies have approached VWM as just serving perception beyond the immediate. Whether and how prospective actions shape information in VWM remains largely unknown, in part because typical experimental setups limit behavior to simple button presses.

Decoding load or selection in visuospatial working memory?

Flexible updating of information in Visual Working Memory (VWM) is crucial to deal with its limited capacity. Previous research has shown that the removal of no longer relevant information takes some time to complete. Here, we sought to study the time course of such removal by tracking the accompanying drop in load through behavioral and neurophysiological measures.

Effects of Context Changes on Memory Reactivation.

While the influence of context on long-term memory (LTM) is well documented, its effects on the interaction between working memory (WM) and LTM remain less understood. In this study, we explored these interactions using a delayed match-to-sample task, where participants (6 males, 16 females) encountered the same target object across six consecutive trials, facilitating the transition from WM to LTM. During half of these target repetitions, the background color changed.

A certain future strengthens the past: Knowing ahead how to act on an object prioritizes its visual working memory representation.

Findings from recent studies indicate that planning an action toward an object strengthens its visual working memory (VWM) representation, emphasizing the importance of sensorimotor links in VWM. In the present study, we investigated to what extent such sensorimotor links are modulated by how well-defined an action plan is. In three eye-tracking experiments, we asked participants to memorize a visual stimulus for a subsequent memory test, whereby they performed a specific hand movement toward memory-matching probes.

Love and hate do not modulate the attentional blink but improve overall performance.

How may feelings of love and hate impact people's attention? We used a modified Attentional Blink (AB) task in which 300 participants were asked to categorise a name representing a person towards whom they felt either hate, love, or neutral (first target) plus identify a number word (second target), both embedded in a rapidly presented stream of other words. The lag to the second target was systematically varied. Contrary to our hypothesis, results revealed that both hated and loved names resulted in higher accuracy for the second target than neutral names, which was largely independent of lag.

Retinal eccentricity modulates saliency-driven but not relevance-driven visual selection.

Where we move our eyes during visual search is controlled by the relative saliency and relevance of stimuli in the visual field. However, the visual field is not homogeneous, as both sensory representations and attention change with eccentricity. Here we present an experiment investigating how eccentricity differences between competing stimuli affect saliency- and relevance-driven selection.

Does crowding predict conjunction search? An individual differences approach.

Searching for objects in the visual environment is an integral part of human behavior. Most of the information used during such visual search comes from the periphery of our vision, and understanding the basic mechanisms of search therefore requires taking into account the inherent limitations of peripheral vision. Our previous work using an individual differences approach has shown that one of the major factors limiting peripheral vision (crowding) is predictive of single feature search, as reflected in response time and eye movement measures.

A CODE model bridging crowding in sparse and dense displays.

Visual crowding is arguably the strongest limitation imposed on extrafoveal vision, and is a relatively well-understood phenomenon. However, most investigations and theories are based on sparse displays consisting of a target and at most a handful of flanker objects. Recent findings suggest that the laws thought to govern crowding may not hold for densely cluttered displays, and that grouping and nearest neighbour effects may be more important.

The effects of eccentricity on attentional capture.

Visual attention may be captured by an irrelevant yet salient distractor, thereby slowing search for a relevant target. This phenomenon has been widely studied using the additional singleton paradigm in which search items are typically all presented at one and the same eccentricity. Yet, differences in eccentricity may well bias the competition between target and distractor.

A matter of availability: sharper tuning for memorized than for perceived stimulus features.

Our visual environment is relatively stable over time. An optimized visual system could capitalize on this by devoting less representational resources to objects that are physically present. The vividness of subjective experience, however, suggests that externally available (perceived) information is more strongly represented in neural signals than memorized information.

How do people find pairs?

Humans continuously scan their visual environment for relevant information. Such visual search behavior has typically been studied with tasks in which the search goal is constant and well-defined, requiring relatively little interplay between memory and orienting. Here we studied a situation in which the target is not known in advance, and instead, memory needs to be dynamically updated during the actual search.

The eyes prefer targets nearby fixation: Quantifying eccentricity-dependent attentional biases in oculomotor selection.

An important function of peripheral vision is to provide the target of the next eye movement. Here we investigate the extent to which the eyes are biased to select a target closer to fixation over one further away. Participants were presented with displays containing two identical singleton targets and were asked to move their eyes to either one of them.

Multi-res: An interface for improving reading without central vision.

Loss of sharp foveal vision, as is inherent to Macular Degeneration (MD), severely impacts reading. One strategy for preserving patients' reading ability involves a one-by-one serial visual presentation (SVP) of words, whereby words are viewed extrafoveally. However, the method is limited as patients often retain the natural tendency to foveate words, thus bringing those words in the scotomal region.

Visual working memory representations bias attention more when they are the target of an action plan.

Attention has frequently been regarded as an emergent property of linking sensory representations to action plans. It has recently been proposed that similar mechanisms may operate within visual working memory (VWM), such that linking an object in VWM to an action plan strengthens its sensory memory representation, which then expresses as an attentional bias. Here we directly tested this hypothesis by comparing attentional biases induced by VWM representations which were the target of a future action, to those induced by VWM representations that were equally task-relevant, but not the direct target of action.

Visual Working Memory Adapts to the Nature of Anticipated Interference.

Visual working memory has been proven to be relatively robust against interference. However, little is known on whether such robust coding is obligatory, or can be flexibly recruited depending on its expected usefulness. To address this, participants remembered both the color and orientation of a grating.

An attentional limbo: Saccades become momentarily non-selective in between saliency-driven and relevance-driven selection.

Human vision involves selectively directing the eyes to potential objects of interest. According to most prominent theories, selection is the quantal outcome of an ongoing competition between saliency-driven signals on the one hand, and relevance-driven signals on the other, with both types of signals continuously and concurrently projecting onto a common priority map. Here, we challenge this view.

Memory for Stimulus Duration Is Not Bound to Spatial Information.

Different theories have been proposed to explain how the human brain derives an accurate sense of time. One specific class of theories, intrinsic clock theories, postulate that temporal information of a stimulus is represented much like other features such as color and location, bound together to form a coherent percept. Here, we explored to what extent this holds for temporal information after it has been perceived and is held in working memory for subsequent comparison.

Neural Repetition Suppression Modulates Time Perception: Evidence From Electrophysiology and Pupillometry.

Human time perception is malleable and subject to many biases. For example, it has repeatedly been shown that stimuli that are physically intense or that are unexpected seem to last longer. Two competing hypotheses have been proposed to account for such biases: One states that these temporal illusions are the result of increased levels of arousal that speeds up neural clock dynamics, whereas the alternative "magnitude coding" account states that the magnitude of sensory responses causally modulates perceived durations.

Individual differences in crowding predict visual search performance.

Visual search is an integral part of human behavior and has proven important to understanding mechanisms of perception, attention, memory, and oculomotor control. Thus far, the dominant theoretical framework posits that search is mainly limited by covert attentional mechanisms, comprising a central bottleneck in visual processing. A different class of theories seeks the cause in the inherent limitations of peripheral vision, with search being constrained by what is known as the functional viewing field (FVF).

The dynamics of saliency-driven and goal-driven visual selection as a function of eccentricity.

Both saliency and goal information are important factors in driving visual selection. Saliency-driven selection occurs primarily in early responses, whereas goal-driven selection happens predominantly in later responses. Here, we investigated how eccentricity affects the time courses of saliency-driven and goal-driven visual selection.

High-pass filtering artifacts in multivariate classification of neural time series data.

Background: Traditionally, EEG/MEG data are high-pass filtered and baseline-corrected to remove slow drifts. Minor deleterious effects of high-pass filtering in traditional time-series analysis have been well-documented, including temporal displacements. However, its effects on time-resolved multivariate pattern classification analyses (MVPA) are largely unknown.

Content or status: Frontal and posterior cortical representations of object category and upcoming task goals in working memory.

To optimize task sequences, the brain must differentiate between current and prospective goals. We previously showed that currently and prospectively relevant object representations in working memory can be dissociated within object-selective cortex. Based on other recent studies indicating that a range of brain areas may be involved in distinguishing between currently relevant and prospectively relevant information in working memory, here we conducted multivoxel pattern analyses of fMRI activity in additional posterior areas (specifically early visual cortex and the intraparietal sulcus) as well as frontal areas (specifically the frontal eye fields and lateral prefrontal cortex).

Flexible Working Memory Through Selective Gating and Attentional Tagging.

Working memory is essential: it serves to guide intelligent behavior of humans and nonhuman primates when task-relevant stimuli are no longer present to the senses. Moreover, complex tasks often require that multiple working memory representations can be flexibly and independently maintained, prioritized, and updated according to changing task demands. Thus far, neural network models of working memory have been unable to offer an integrative account of how such control mechanisms can be acquired in a biologically plausible manner.

Attention for action in visual working memory.

From the conception of Baddeley's visuospatial sketchpad, visual working memory and visual attention have been closely linked concepts. An attractive model has advocated unity of the two cognitive functions, with attention serving the active maintenance of sensory representations. However, empirical evidence from various paradigms and dependent measures has now firmly established an at least partial dissociation between visual attention and visual working memory maintenance - thus leaving unclear what the relationship between the two concepts is.

Oscillatory Control over Representational States in Working Memory.

In the visual world, attention is guided by perceptual goals activated in visual working memory (VWM). However, planning multiple-task sequences also requires VWM to store representations for future goals. These future goals need to be prevented from interfering with the current perceptual task.