Space and time support visual working memory (VWM) by providing incidental reference frames for task-relevant information. While this has been studied with stationary items, natural scenes also contain moving objects, whose positions change over time, often in a predictable manner. We investigated if predictable item motion is leveraged to facilitate VWM for surface features. In a dynamic change-detection task, participants memorised the colours of three disks moving at constant speed in different directions before disappearing. After a retention interval, the disks reappeared (a) at the movement endpoint locations where they had disappeared (b) at positions spatiotemporally congruent with their previous motion (where they would have been had they continued their movement), (c) at positions with a temporal offset (consistent with a change in speed while out of view) or (d) at positions with a spatial offset (consistent with a change in movement direction). Performance decreased with increasing temporal or spatial offsets relative to congruent positions, indicating that the memorised items' positions were remapped to their anticipated future locations. This updating of positions in spatiotemporal reference frames, however, only occurs if motion extrapolation allows for reliable predictions of where occluded items will reappear. In a task context with unreliable motion patterns, the congruency effect diminished over time and performance instead increased at the movement endpoints. A second experiment confirmed this influence of motion reliability. Thus, predictable motion is extrapolated to update spatiotemporal reference frames in VWM, supporting memory for surface features and thereby contributing to visually guided behavior in dynamic environments.

Natural environments provide a rich spatiotemporal context that allows for visual objects to be differentiated based on different types of information: their absolute or relative spatial or temporal coordinates, or their ordinal positions in a spatial or temporal sequence. Here, we investigated which spatial and temporal properties are incidentally encoded along with to-be-remembered features to provide reference frames in visual working memory (VWM). We tested the different possibilities in a spatiotemporal color change-detection task by transforming spatial and/or temporal structures of item presentation at retrieval relative to encoding. More precisely, spatial and/or temporal coordinates were (a) switched, changing the order of items in a spatial or temporal sequence (ordinal transformation); (b) multiplied by different factors, changing interitem distances (relational transformation); or (c) multiplied by a constant factor, expanding or shrinking the entire configuration (global transformation). Such transformations of the external reference frame at retrieval should only interfere with VWM if the internal reference frame relies on the spatial or temporal properties affected by the respective transformation. We found that ordinal and relational transformations of either the spatial or temporal structure impaired performance, whereas global transformations did not. Thus, reference frames appear to be primarily defined by interitem relations-including relative distances between items as well as their order-rather than absolute positions in space or time. These results corroborate and extend previous findings for the spatial domain, and highlight functional similarities of the spatial and temporal dimensions in VWM by revealing the same metrical properties for temporal reference frames. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

Visual events are structured in space and time, yet models of visual working memory (VWM) have largely relied on tasks emphasizing spatial aspects. Here, we show that temporal properties of visual events are incidentally encoded along with spatial properties. In five experiments, participants performed change-detection tasks, in which items had unique spatial and temporal coordinates at encoding. Crucially, neither space nor time was task-relevant. The key manipulation concerned the retrieval context: The test array was identical to the memory array either in its entire spatiotemporal structure, or only its spatial or temporal structure. Removing spatial or temporal information at retrieval resulted in costs, indicating that memory relied on both spatial and temporal context in which items were initially perceived. Encoding of spatiotemporal structure occurred incidentally, not strategically, as it was robust even when the retrieval context was perfectly predictable. However, spatial and temporal inter-item spacings influenced the weighting of spatial and temporal information: It favoured the domain in which items were more widely spaced, facilitating their individuation and, likely, access to representations. Across individuals, the weighting of spatial and temporal information varied substantially, but it remained consistent across sessions, suggesting stable preferences for coding in the spatial or temporal domain. No comparable incidental encoding occurred for other task-irrelevant feature dimensions (size or colour). We propose that temporal structure serves as fundamental a function in VWM as spatial structure, scaffolding events that unfold over time.

Different visual attributes effectively guide attention to specific items in visual working memory (VWM), ensuring that particularly important memory contents are readily available. Predictable temporal structures contribute to this efficient use of VWM: items are prospectively prioritized when they are expected to be needed. Occasionally, however, visual events only gain relevance through their timing after they have passed. We investigated retrospective attentional orienting based on temporal position by directly comparing it with orienting to spatial locations, which is typically considered the most powerful selection mechanism. In a colour-change-detection task, in which items appeared sequentially at different locations, symbolic number cues validly indicated the temporal or spatial location of the upcoming probe item either before encoding (precues; Experiment 1) or during maintenance (retrocues; Experiments 1-3). Temporal and spatial cues were physically identical and only differed in their mapping onto either temporal or spatial positions. Predictive cues yielded cueing benefits (i.e., higher accuracy and shorter reaction times) as compared with neutral cues, with larger benefits for precues than for retrocues. Importantly, spatial and temporal cueing benefits did not differ. Equivalent retrocueing benefits were also observed across different cue-probe intervals and irrespective of whether spatial or temporal position was used as retrieval cue, indicating that items were directly bound to temporal position and not prioritized via a space-based mechanism. These findings show that spatial and temporal properties can be used equally well to flexibly prioritise representations held in VWM and they highlight the functional similarities of space and time in VWM.

Space and time structure our visual experience, yet little is known about the role of temporal aspects for visual working memory (VWM). We have recently shown that both spatial and temporal properties are incidentally encoded along with to-be-remembered information, providing reference frames for storage and retrieval. In our prior work, we used rich spatiotemporal contexts, as they might be encountered in natural environments: Memory contents could be differentiated based on (a) absolute spatial/temporal coordinates, (b) relative spatial/temporal coordinates, or (c) their position in a categorical spatial/temporal order. The drawback of this approach is that it leaves open the question of specifically which spatiotemporal properties are critical. In a series of experiments, we used a colour change-detection task to test each of these possibilities by transforming spatial and/or temporal structures of item presentation at retrieval relative to encoding. More specifically, spatial and/or temporal coordinates were (a) multiplied by a constant factor, expanding or shrinking the entire configuration (global change), (b) multiplied by different factors, changing relative inter-item distances (relational change), or (c) switched, changing the order of items in a spatial or temporal sequence (ordinal change). Such transformations of the external reference frame at retrieval should only affect performance if the metric of the internal reference frame in VWM is not invariant to this type of transformation. We found that ordinal and relational changes of either the spatial or temporal structure impaired performance, whereas global changes had no effect. Thus, reference frames appear to be established by inter-item relations – including relative distances between items as well as their order – rather than absolute positions in space or time. These results corroborate and extend previous findings for the spatial domain, and highlight functional similarities between the spatial and temporal dimensions by revealing the same metrical properties for temporal reference frames.

Background and aims: Attentional biases contribute to the maintenance of addictive behaviors. For the problematic use of online gaming-recognized as Internet Gaming Disorder (IGD)-first evidence points to a bias towards in-game stimuli. This study aimed to provide behavioral and electrophysiological evidence for a generalized bias towards computer-related stimuli, and to identify the specific attentional processes contributing to this bias: facilitated attention deployment, impaired disengagement or failed suppression. Method: Twenty participants with IGD and 23 casual gamers performed a visual search task with photographs of real-world objects. Either the target or a to-be-ignored distractor was addiction-relevant (computer-related), whereas all other items were addiction-irrelevant (related to cars or sport). Event-related potential components associated with facilitated attentional deployment to the target (NT), its post-selection processing (SPCN), and suppression of irrelevant information (PD) were analyzed. Results: Unlike casual gamers, gamers with IGD exhibited prolonged reaction times and increased SPCN amplitudes for computer-related stimuli, reflecting their continued attentional processing. At the individual level, larger SPCN amplitudes were associated with longer delays in reaction time. Discussion and Conclusions: This pattern of results indicates that the disengagement of attention from computer-related stimuli is impaired in IGD. More generally, our findings demonstrate that conditioning processes occur in IGD, and thus open up new avenues for treatment.

ABSTRACT Perception is shaped by actions, which determine the allocation of selective attention across the visual field. Here, we review evidence that maintenance in visual working memory is similarly influenced by actions (eye or hand movements), planned and executed well after encoding: Representations that are relevant for an upcoming action – because they spatially correspond to the action goal or because they are defined along action-related feature dimensions – are automatically prioritised over action-irrelevant representations and held in a stable state. We summarise what is known about specific characteristics and mechanisms of selection-for-action in working memory, such as its temporal dynamics and spatial specificity, and delineate open questions. This newly-burgeoning area of research promotes a more functional perspective on visual working memory that emphasizes its role in action control.

All natural visual events exhibit a spatiotemporal structure, but our understanding of how temporal aspects are represented lags far behind our understanding of the role of space. Here, we present data indicating that a combination of both the spatial and the temporal structure of visual events provides frames of reference for storage in working memory. In a series of experiments, participants performed a change detection task, for which they memorized colours presented sequentially at different locations and with different stimulus onset asynchronies. Each item could be uniquely identified by its spatial or temporal coordinates, but neither spatial nor temporal information was task-relevant. The key manipulation was that of retrieval context: The test array was identical to the memory array in terms of either its entire spatiotemporal structure, or only its spatial or temporal components. Removing either spatial or temporal information at retrieval impaired performance, indicating that memory relied, at least to some degree, on the spatiotemporal structure in which items were initially perceived. Overall, more weight appeared to be assigned to the spatial structure, but there were pronounced individual differences in the relative weighting of spatial and temporal information, which were fairly consistent throughout and across sessions. Conceivably, these are indicative of stable individual preferences for coding in the spatial or temporal domain. We observed no substantial differences between a randomly interleaved and a blocked variation of retrieval context, suggesting that encoding in a spatiotemporal frame of reference was not strategically adjusted to task demands. However, the inter-item spacing of spatial and temporal structures influenced the relative weighting of spatial and temporal information. Favouring the frame of reference that is more widely spaced presumably facilitates item individuation and thereby access to representations. We propose that time may serve a similar function as space in the architecture of visual working memory.

It is well known that processing at upcoming target locations can be facilitated, but mixed results have been obtained regarding the inhibition of irrelevant locations when advance information about distractors is available on a trial-to-trial basis. Here, we provide electrophysiological evidence that distractor locations can be anticipatorily suppressed. In an additional singleton search task, distractor cues were presented before the search display, which were either fully predictive or non-predictive of the location of the upcoming salient colour distractor. The PD component of the event-related potential, a marker of active suppression, was elicited by lateral singletons and smaller following predictive than non-predictive cues, indicating that less suppression was required upon presentation of the distractor when its location was known in advance. Presumably, excitability of regions processing the predictively cued locations was anticipatorily reduced to prevent distraction. This idea was further supported by the finding that larger individual cueing benefits in reaction time were associated with stronger reductions of the PD. There was no behavioural benefit at the group level, however, and implications for the role of individual differences and for the measurement of inhibition in distractor cueing tasks are discussed. The enhancement of target locations, reflected by the NT component, was not modulated by the predictiveness of the cues. Overall, our findings add to a growing literature highlighting the importance of inhibitory mechanisms for the guidance of spatial attention by showing that irrelevant locations can be anticipatorily suppressed in a top-down fashion, reducing the impact of even salient stimuli.

When making decisions, humans can maximize the positive outcome of their actions by choosing the option associated with the highest reward. We have recently shown that choices modulate effects of reward via a bias in spatial attention: Locations associated with a lower reward are anticipatorily suppressed, as indicated by delayed responses to low-reward targets and increased parieto-occipital alpha power. Here, we investigated whether this inhibition also occurs when reward is not coupled to location but to a nonspatial feature (color). We analyzed reaction times to single targets associated with a low or high reward as a function of whether a second trial type, choice-trials, were interleaved. In choice-trials, participants could choose either one of two targets to obtain the associated reward. Indeed, responses to low-reward targets were slower when choice-trials were present, magnifying the influence of reward, and this delay was more pronounced in trials immediately following a choice. No corresponding changes in parieto-occipital alpha power were observed, but the behavioral findings suggest that choices modulate a reward-related bias in feature-based attention in a similar manner as for spatial attention, and support the idea that reward primarily affects behaviour when it is of immediate relevance.

Visual working memory contents can be selectively weighted according to differences in their task-relevance. In the present study, we examined the influence of two more indirect selection biases established by a concurrent task or learned reward associations: action relevance and motivational value. In three experiments, memory performance was assessed with the same color change detection task. Potential action relevance and motivational value were each determined by a specific feature of the memory items (location or shape, respectively) and manipulated orthogonally. Investigated separately (Experiments 1A and 1B), both selection biases modulated visual working memory. In combination (Experiment 2), action relevance and motivational value still each exerted an influence, but not in a fully independent and additive manner. While action relevance impacted performance irrespective of the reward associated with the items, an effect of motivational value was only observed for action-relevant items. These results support the notion that visual working memory is automatically biased as an inherent part of action planning. More generally, these findings highlight the versatile nature of visual working memory: Contents can be flexibly weighted to reflect differences in their importance, taking into account several sources of information.

When humans have to choose between different options, they can maximize their payoff by choosing the option that yields the highest reward. Information about reward is not only used to optimize decisions but also for movement preparation to minimize reaction times to rewarded targets. Here, we show that this is especially true in contexts in which participants additionally have to choose between different options. We probed eye movement preparation by measuring saccade latencies to differently rewarded single targets (single-trial) appearing left or right from fixation. In choice-trials, both targets were displayed and participants were free to decide for one target to receive the corresponding reward. In blocks without choice-trials, single-trial latencies were not or only weakly affected by reward. With choice-trials present, the influence of reward increased with the proportion and difficulty of choices and decreased when a cue indicated that no choice will be necessary. Choices caused a delay in subsequent single-trial responses to the non-chosen option. Taken together, our results suggest that reward affects saccade preparation mainly when the outcome is uncertain and depends on the participants' behavior, for instance when they have to choose between targets differing in reward.

Positive outcome of actions can be maximized by choosing the option with the highest reward. For saccades, it has recently been suggested that the necessity to choose is, in fact, an important factor mediating reward effects: latencies to single low-reward targets increased with an increasing proportion of interleaved choice-trials, in which participants were free to choose between two targets to obtain either a high or low reward. Here, we replicate this finding for manual responses, demonstrating that this effect of choice is a more general, effector-independent phenomenon. Oscillatory activity in the alpha and beta band in the preparatory period preceding target onset was analysed for a parieto-occipital and a centrolateral region of interest to identify an anticipatory neural biasing mechanism related to visuospatial attention or motor preparation. When the proportion of interleaved choices was high, an increase in lateralized posterior alpha power indicated that the hemifield associated with a low reward was suppressed in preparation for reward-maximizing target selection. The larger the individual increase in lateralized alpha power, the slower the reaction times to low-reward targets. At a broader level, these findings support the notion that reward only affects responses when behaviour can be optimized to maximize positive outcome.

Information maintained in visual working memory (VWM) can be strategically weighted according to its task-relevance. This is typically studied by presenting cues during the maintenance interval, but under natural conditions, the importance of certain aspects of our visual environment is mostly determined by intended actions. We investigated whether representations in VWM are also weighted with respect to their potential action relevance. In a combined memory and movement task, participants memorized a number of items and performed a pointing movement during the maintenance interval. The test item in the memory task was subsequently presented either at the movement goal or at another location. We found that performance was better for test items presented at a location that corresponded to the movement goal than for test items presented at action-irrelevant locations. This effect was sensitive to the number of maintained items, suggesting that preferential maintenance of action relevant information becomes particularly important when the demand on VWM is high. We argue that weighting according to action relevance is mediated by the deployment of spatial attention to action goals, with representations spatially corresponding to the action goal benefitting from this attentional engagement. Performance was also better at locations next to the action goal than at locations farther away, indicating an attentional gradient spreading out from the action goal. We conclude that our actions continue to influence visual processing at the mnemonic level, ensuring preferential maintenance of information that is relevant for current behavioral goals.

Planning an action primes feature dimensions that are relevant for that particular action, increasing the impact of these dimensions on perceptual processing. Here, we investigated whether action planning also affects the short-term maintenance of visual information. In a combined memory and movement task, participants were to memorize items defined by size or color while preparing either a grasping or a pointing movement. Whereas size is a relevant feature dimension for grasping, color can be used to localize the goal object and guide a pointing movement. The results showed that memory for items defined by size was better during the preparation of a grasping movement than during the preparation of a pointing movement. Conversely, memory for color tended to be better when a pointing movement rather than a grasping movement was being planned. This pattern was not only observed when the memory task was embedded within the preparation period of the movement, but also when the movement to be performed was only indicated during the retention interval of the memory task. These findings reveal that a weighting of information in visual working memory according to action relevance can even be implemented at the representational level during maintenance, demonstrating that our actions continue to influence visual processing beyond the perceptual stage.

Visual working memory can be modulated according to changes in the cued task relevance of maintained items. Here, we investigated the mechanisms underlying this modulation. In particular, we studied the consequences of attentional selection for selected and unselected items, and the role of individual differences in the efficiency with which attention is deployed. To this end, performance in a visual working memory task as well as the CDA/SPCN and the N2pc, ERP components associated with visual working memory and attentional processes, were analysed. Selection during the maintenance stage was manipulated by means of two successively presented retrocues providing spatial information as to which items were most likely to be tested. Results show that attentional selection serves to robustly protect relevant representations in the focus of attention while unselected representations which may become relevant again still remain available. Individuals with larger retrocueing benefits showed higher efficiency of attentional selection, as indicated by the N2pc, and showed stronger maintenance-associated activity (CDA/SPCN). The findings add to converging evidence that focused representations are protected, and highlight the flexibility of visual working memory, in which information can be weighted according its relevance.

Attention can be deployed to representations in visual working memory (VWM), ensuring that only the most relevant information is maintained. We investigated whether the attentional selection of VWM representations can operate on features just as well as on spatial information, and we used transcranial magnetic stimulation (TMS) to test whether these attentional mechanisms can be dissociated based on the site of cortical stimulation. During the retention interval of a VWM task, a so-called retrocue was presented, which was either uninformative or indicated the item that would be tested at the end of the trial. The test item was cued by its location (spatial attention) or by its shape (feature-based attention). During cue presentation, TMS was applied to the supramarginal gyrus (SMG), which has been implicated in spatial attention, or to the lateral occipital cortex (LO), which is involved in representing object shape. We observed improved memory for objects cued by location and shape, confirming that both spatial as well as featural information can be used for selecting representations in VWM. Importantly, stimulation of SMG selectively facilitated spatial attention and stimulation of LO selectively facilitated feature-based attention. These results show that spatial and feature-based attentional mechanisms in VWM recruit distinct cortical regions. The same regions have been shown to be involved in attention to external events, indicating that attention in the mnemonic and in the perceptual domain are similarly implemented at the neural level. In general, these findings extend our understanding of how attentional mechanisms operating on different types of information optimize the use of the highly limited VWM system, allowing for an efficient and flexible updating of its contents. Meeting abstract presented at VSS 2016

The contents of visual working memory (VWM) can be modulated by spatial cues presented during the maintenance interval (“retrocues”). Here, we examined whether attentional selection of representations in VWM can also be based on features. In addition, we investigated whether the mechanisms of feature-based and spatial attention in VWM differ with respect to parallel access to noncontiguous locations. In two experiments, we tested the efficacy of valid retrocues relying on different kinds of information. Specifically, participants were presented with a typical spatial retrocue pointing to two locations, a symbolic spatial retrocue (numbers mapping onto two locations), and two feature-based retrocues: a color retrocue (a blob of the same color as two of the items) and a shape retrocue (an outline of the shape of two of the items). The two cued items were presented at either contiguous or noncontiguous locations. Overall retrocueing benefits, as compared to a neutral condition, were observed for all retrocue types. Whereas feature-based retrocues yielded benefits for cued items presented at both contiguous and noncontiguous locations, spatial retrocues were only effective when the cued items had been presented at contiguous locations. These findings demonstrate that attentional selection and updating in VWM can operate on different kinds of information, allowing for a flexible and efficient use of this limited system. The observation that the representations of items presented at noncontiguous locations could only be reliably selected with feature-based retrocues suggests that feature-based and spatial attentional selection in VWM rely on different mechanisms, as has been shown for attentional orienting in the external world.