Visual Working Research Articles

Integrated encoding of relations and objects in visual working memory.

Comprehensive understanding of visual scenes necessitates grasping the relations among visual objects. Given the potentially pivotal role of visual working memory (VWM) in processing visual relations, it is important to investigate the representation of relations in VWM. In our previous study, we proposed the integrated storage hypothesis, postulating that relations and objects are stored together as an integrated structured representation in VWM. The present study aimed to test this hypothesis against the alternative separate encoding hypothesis by probing the irrelevant-distracting effect. Across three experiments, where participants memorized object shapes/colors while disregarding relations, an irrelevant-distracting effect was consistently observed across varying types of changes in relation and set sizes. Critically, recombining the probe with irrelevant relation from another memory item (Experiment 2) or reversing the relational roles of probed objects relative to the memory item (Experiment 3) were perceived as inconsistency with stored representations and impaired change detection. These findings supported the integrated storage hypothesis, indicating that the dynamic relations between the objects are automatically encoded alongside object identities to form an integrated structured representation. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

Modifiable dementia risk factors associated with objective and subjective cognition.

Early detection of both objective and subjective cognitive impairment is important. Subjective complaints in healthy individuals can precede objective deficits. However, the differential associations of objective and subjective cognition with modifiable dementia risk factors are unclear. We gathered a large cross-sectional sample (N=3327, age 18 to 84) via a smartphone app and quantified the associations of 13 risk factors with subjective memory problems and three objective measures of executive function (visual working memory, cognitive flexibility, model-based planning). Depression, socioeconomic status, hearing handicap, loneliness, education, smoking, tinnitus, little exercise, small social network, stroke, diabetes, and hypertension were all associated with impairments in at least one cognitive measure. Subjective memory had the strongest link to most factors; these associations persisted after controlling for depression. Age mostly did not moderate these associations. Subjective cognition was more sensitive to self-report risk factors than objective cognition. Smartphones could facilitate detecting the earliest cognitive impairments. Smartphone assessments of cognition were sensitive to dementia risk factors. Subjective cognition had stronger links to most factors than did objective cognition. These associations were not fully explained by depression. These associations were largely consistent across the lifespan.

Unravelling the object-based nature of visual working memory: insight from pointers.

Visual working memory (VWM) plays a crucial role in temporarily storing and processing visual information, but the nature of stored representations and their interaction with new inputs has long been unclear. The pointer system refers to how VWM links new sensory inputs to stored information using specific cues. This study aimed to investigate whether the pointer system is based on spatial, feature-based, or object-based cues by employing the repetition benefit effect, where memory performance improves with repeated memory items. Across three experiments, we manipulated spatial positions, shapes, and colors as pointer cues to determine how these features affect VWM consolidation and updating. The results showed that while spatial location serves as a strong pointer cue, shape and color features can also effectively reestablish object correspondence in VWM. These findings support the view that the pointer system in VWM is flexible and object-based, utilizing various feature cues to maintain memory continuity. This study provides new insights into how VWM connects new inputs with stored information through the pointer system.

7838 Improvement of Cognition and Memory Scores in Transgender Individuals Within One Year of Initiating Gender-Affirming Hormone Therapy

Abstract Disclosure: C.M. Godar: None. S.C. De La Torre: None. O. Bonsu: None. M.K. Shakir: None. T.D. Hoang: None. Introduction: The use of gender-affirming hormone therapy (GAHT) in transgender individuals is known to provide many beneficial health effects to reduce gender dysphoria, reduce depressive symptoms, and increase overall quality of life. Cognitive function and memory ability are known to be influenced by sex hormone levels in studies of hormone replacement therapy in post-menopausal women, but studies of GAHT’s effects on cognition and memory in transgender patients have been scarcely reported. We discuss a study of cognitive testing in transgender individuals before and after 12 months of gender-affirming feminizing or masculinizing hormone therapy using a validated cognitive assessment tool. Methods: A prospective study of 32 transgender patients aged 18-45 years was approved by IRB at an academic medical center. The Wechsler Memory Scale 4th edition (WMS®-IV, Pearson) was administered to 19 transgender females and 13 transgender males prior to initiation of GAHT and again after one year of GAHT use. Mean scores were analyzed and reported for five categories of cognitive and memory function: auditory memory (AMI), visual memory (VMI), visual working memory (VWMI), immediate memory (IMI), and delayed memory (DMI). Mean scores for baseline and 12-month data were analyzed for total population and male and female subgroups. Results: Baseline mean WMS-IV values for the total study population were: AMI 105 points, VMI 78 points, VWMI 107 points, IMI 88 points, DMI 91 points. Mean values after 12 months of GAHT were: AMI 120 points, VMI 81 points, VWMI 110 points, IMI 99 points, DMI 102 points. Mean percent change from baseline to 12 months was as follows: AMI 13.4%, VMI 8.9%, VWMI 2.6%, IMI 12.8%, DMI 13%. Similar patterns were noted for both gender subgroups. Discussion: It is well-known that transgender individuals are subject to higher rates of depression, anxiety, and suicidality compared to the general population. Decreased cognitive function and memory are known effects of untreated depression. Our study demonstrated that treatment of gender dysphoria with GAHT provided a tangible cognitive and memory benefit. The long-term impact of GAHT on cognition and memory is not known and deserves additional study. Limitations of this study included the absence of a cis-gender control group and inability to stratify data based on age, which may provide additional significance. Presentation: 6/2/2024

7838 Improvement of Cognition and Memory Scores in Transgender Individuals Within One Year of Initiating Gender-Affirming Hormone Therapy

Abstract Disclosure: C.M. Godar: None. S.C. De La Torre: None. O. Bonsu: None. M.K. Shakir: None. T.D. Hoang: None. Introduction: The use of gender-affirming hormone therapy (GAHT) in transgender individuals is known to provide many beneficial health effects to reduce gender dysphoria, reduce depressive symptoms, and increase overall quality of life. Cognitive function and memory ability are known to be influenced by sex hormone levels in studies of hormone replacement therapy in post-menopausal women, but studies of GAHT’s effects on cognition and memory in transgender patients have been scarcely reported. We discuss a study of cognitive testing in transgender individuals before and after 12 months of gender-affirming feminizing or masculinizing hormone therapy using a validated cognitive assessment tool. Methods: A prospective study of 32 transgender patients aged 18-45 years was approved by IRB at an academic medical center. The Wechsler Memory Scale 4th edition (WMS®-IV, Pearson) was administered to 19 transgender females and 13 transgender males prior to initiation of GAHT and again after one year of GAHT use. Mean scores were analyzed and reported for five categories of cognitive and memory function: auditory memory (AMI), visual memory (VMI), visual working memory (VWMI), immediate memory (IMI), and delayed memory (DMI). Mean scores for baseline and 12-month data were analyzed for total population and male and female subgroups. Results: Baseline mean WMS-IV values for the total study population were: AMI 105 points, VMI 78 points, VWMI 107 points, IMI 88 points, DMI 91 points. Mean values after 12 months of GAHT were: AMI 120 points, VMI 81 points, VWMI 110 points, IMI 99 points, DMI 102 points. Mean percent change from baseline to 12 months was as follows: AMI 13.4%, VMI 8.9%, VWMI 2.6%, IMI 12.8%, DMI 13%. Similar patterns were noted for both gender subgroups. Discussion: It is well-known that transgender individuals are subject to higher rates of depression, anxiety, and suicidality compared to the general population. Decreased cognitive function and memory are known effects of untreated depression. Our study demonstrated that treatment of gender dysphoria with GAHT provided a tangible cognitive and memory benefit. The long-term impact of GAHT on cognition and memory is not known and deserves additional study. Limitations of this study included the absence of a cis-gender control group and inability to stratify data based on age, which may provide additional significance. Presentation: 6/2/2024

Electrophysiological Correlates of Visual Memory Search.

In everyday life, we frequently engage in 'hybrid' visual and memory search, where we look for multiple items stored in memory (e.g., a mental shopping list) in our visual environment. Across three experiments, we used event-related potentials to better understand the contributions of visual working memory (VWM) and long-term memory (LTM) during the memory search component of hybrid search. Experiments 1 and 2 demonstrated that the FN400 - an index of LTM recognition - and the CDA -an index of VWM load - increased with memory set size (target load), suggesting that both VWM and LTM are involved in memory search, even when target load exceeds capacity limitations of VWM. In Experiment 3, we used these electrophysiological indices to test how categorical similarity of targets and distractors affects memory search. The CDA and FN400 were modulated by memory set size only if items resembled targets. This suggests that dissimilar distractor items can be rejected before eliciting a memory search. Together, our findings demonstrate the interplay of VWM and LTM processes during memory search for multiple targets.

Intrinsic functional networks for distinct sources of error in visual working memory.

Visual working memory (VWM) is a core cognitive function wherein visual information is stored and manipulated over short periods. Response errors in VWM tasks arise from the imprecise memory of target items, swaps between targets and nontargets, and random guesses. However, it remains unclear whether these types of errors are underpinned by distinct neural networks. To answer this question, we recruited 80 healthy adults to perform delayed estimation tasks and acquired their resting-state functional magnetic resonance imaging scans. The tasks required participants to reproduce the memorized visual feature along continuous scales, which, combined with mixture distribution modeling, allowed us to estimate the measures of memory precision, swap errors, and random guesses. Intrinsic functional connectivity within and between different networks, identified using a hierarchical clustering approach, was estimated for each participant. Our analyses revealed that higher memory precision was associated with increased connectivity within a frontal-opercular network, as well as between the dorsal attention network and an angular-gyrus-cerebellar network. We also found that coupling between the frontoparietal control network and the cingulo-opercular network contributes to both memory precision and random guesses. Our findings demonstrate that distinct sources of variability in VWM performance are underpinned by different yet partially overlapping intrinsic functional networks.

"Visual verbs": Dynamic event types are extracted spontaneously during visual perception.

During visual processing, input that is continuous in space and time is segmented, resulting in the representation of discrete tokens-objects or events. And there has been a great deal of research about how object representations are generalized into types-as when we see an object as an instance of a broader category (e.g., an animal or plant). There has been much less attention, however, to the possibility that vision represents dynamic information in terms of a small number of primitive event types (such as twisting or bouncing). (In models that posit a "language of vision," these would be the foundational visual verbs.) Here we ask whether such event types are extracted spontaneously during visual perception, even when entirely task irrelevant during passive viewing. We exploited the phenomenon of categorical perception-wherein differences are more readily noticed when they are represented in terms of different underlying categories. Observers were better at detecting changes to images or short videos when the changes involved switches in the underlying event type-even when the changes that maintained the same event type were objectively larger (in terms of both brute image metrics and higher level feature change). We observed this categorical "cross-event-type" advantage for visual working memory for twisting versus rotating, scooping versus pouring, and rolling versus bouncing. Moreover, additional control experiments confirmed that such effects could not be explained by appeal to lower-level non-categorical stimulus differences. This spontaneous perception of "visual verbs" might promote both generalization and prediction about how events are likely to unfold. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

Action Planning Renders Objects in Working Memory More Attentionally Salient.

A rapidly growing body of work suggests that visual working memory (VWM) is fundamentally action oriented. Consistent with this, we recently showed that attention is more strongly biased by VWM representations of objects when we plan to act on those objects in the future. Using EEG and eye tracking, here, we investigated neurophysiological correlates of the interactions between VWM and action. Participants (n = 36) memorized a shape for a subsequent VWM test. At test, a probe was presented along with a secondary object. In the action condition, participants gripped the actual probe if it matched the memorized shape, whereas in the control condition, they gripped the secondary object. Crucially, during the VWM delay, participants engaged in a visual selection task, in which they located a target as fast as possible. The memorized shape could either encircle the target (congruent trials) or a distractor (incongruent trials). Replicating previous findings, we found that eye gaze was biased toward the VWM-matching shape and, importantly, more so when the shape was directly associated with an action plan. Moreover, the ERP results revealed that during the selection task, future action-relevant VWM-matching shapes elicited (1) a stronger Ppc (posterior positivity contralateral), signaling greater attentional saliency; (2) an earlier PD (distractor positivity) component, suggesting faster suppression; (3) a larger inverse (i.e., positive) sustained posterior contralateral negativity in incongruent trials, consistent with stronger suppression of action-associated distractors; and (4) an enhanced response-locked positivity over left motor regions, possibly indicating enhanced inhibition of the response associated with the memorized item during the interim task. Overall, these results suggest that action planning renders objects in VWM more attentionally salient, supporting the notion of selection-for-action in working memory.

Attentional templates for target features versus locations

Visual search is guided by visual working memory representations (i.e., attentional templates) that are activated prior to search and contain target-defining features (e.g., color). In the present study, we tested whether attentional templates can also contain spatial target properties (knowing where to look for) and whether attentional selection guided by such feature-specific templates is equally efficient than selection that is based on feature-specific templates (knowing what to look for). In every trial, search displays were either preceded by semantic color or location cues, indicating the upcoming target color or location, respectively. Qualitative differences between feature- and location-based template guidance were substantiated in terms of selection efficiency in low-load (one target color/location) versus high-load trials (two target colors/locations). Behavioral and electrophysiological (N2pc) measures of target selection speed and accuracy were combined for converging evidence. In line with previous studies, we found that color search was highly efficient, even under high-low conditions, when multiple attentional templates were activated to guide attentional selection in a spatially global fashion. Importantly, results in the location task almost perfectly mirrored the findings of the color task, suggesting that multiple templates for different target locations were activated concurrently when two possible target locations were task relevant. Our findings align with accounts that assume a common neuronal network during preparation for location and color search, but regard spatial and feature-based selection mechanisms as independent.

Effects of Locus Coeruleus Activation on n-Back Performance and Frontoparietal Activity.

Previous studies have linked working memory capacity to restricted hemodynamic responses within critical nodes of the frontoparietal network. Emerging evidence suggests a potential role of the locus coeruleus (LC) in modulating activation of key regions essential for working memory function. This study investigated this hypothesis by examining changes in BOLD signal within the LC and cortex during a parametrically designed verbal working memory task (n-back). fMRI revealed load-dependent task activation, with maximum activation of presumed LC neurons positively correlating with working memory capacity. Furthermore, increased hemodynamic responses in the superior parietal lobes and dorsolateral pFC corresponded with the magnitude of LC activation near working memory capacity limits. An exploratory functional connectivity analysis suggests improvements in working memory performance rely on negative functional connectivity between the LC and cortical regions not primarily involved in task completion. On the basis of previous evidence, this association may represent inhibitory input from cortical regions, enabling phasic bursts of activity from LC neurons, thereby facilitating enhanced cortical activation. This result may also indicate noradrenergic suppression of cortical regions that are not crucial for task completion, leading to enhanced network efficiency. These findings suggest a mechanism by which the LC may improve verbal working memory performance by facilitating enhanced activation in regions critical for visual working memory capacity and active maintenance, potentially enhancing network efficiency.

Potential Biomarkers of Dysmenorrhea Relief: A MEG Study of Hinoki Aromatherapy and Working Memory.

Background/Objectives: This study explored the potential of Hinoki aromatherapy to induce biomarkers of dysmenorrhea relief through working memory. Structural magnetic resonance imaging and magnetoencephalography (MEG) were used to examine their effects on neurophysiological responses to a visual working memory (VWM) test. Behavioral performance was measured to understand its effects on the overall working memory. Methods: Twenty-four healthy participants completed the VWM task during nonmenstruation and menstruation. Behavioral (accuracy and reaction time) and neurophysiological (event-related fields, source estimation, and permutation t-test on source data) measures were assessed without and with Hinoki aromatherapy. Results: A significant difference in the ratio of accuracy to reaction time was found without and with aromatherapy in participants with dysmenorrhea, suggesting that aromatherapy may improve working memory performance in this population. MEG analysis revealed high temporal resolution of evoked latency and intensity during the VWM task. Source localization of the activation aimed to identify brain areas involved in dysmenorrhea. Aromatherapy reduced signals in these areas, which may also contribute to reducing dysmenorrhea-related visual signals. Conclusions: Based on these findings, Hinoki aromatherapy may be a promising treatment option for alleviating dysmenorrhea and improving related symptoms by reducing activity in brain pain processing regions. These regions include the left entorhinal cortex, inferior temporal gyrus, primary visual cortex, retrosplenial cortex, and presubiculum. Furthermore, decreased activity in these areas with aromatherapy suggests that they could be used as biomarkers of dysmenorrhea relief.

Conceptual masking disrupts change-detection performance.

The present study investigated the effects of long-term knowledge on backward masking interference in visual working memory (VWM) by varying the similarity of mask stimuli along categorical dimensions. To-be-remembered items and masks were taken from categories controlled for perceptual distinctiveness and distinctiveness in kinds (e.g., there are many kinds of cars and few kinds of coffee mugs). Participants completed a change-detection task in which the memory array consisted of exemplars from either a similar or distinctive category, followed by a mask array of items from the same category (conceptually similar versus conceptually distinct categories), a different category, or no mask. The results over two experiments showed greater interference from conceptually similar masks as compared with the other conditions across stimulus onset asynchrony (SOA) conditions, suggesting masking with conceptually similar categories leads to more interference even when masks are shown well after the stimulus. These results have important implications for both the nature and time course of long-term conceptual knowledge influencing VWM, particularly when using complex real-world objects.

On the lasting impact of mild traumatic brain injury on working memory: Behavioural and electrophysiological evidence

Despite increasing recognition of the significance of mild traumatic brain injury (mTBI), the long-term cognitive consequences of the injury remain unclear. More sensitive measures that can detect subtle cognitive changes and consideration of individual variability are needed to properly characterise cognitive outcomes following mTBI. Here, we used complex behavioural tasks, individual differences approaches, and electrophysiology to investigate the long-term cognitive effects of a history of mTBI. In Experiment 1, participants with self-reported mTBI history (n=82) showed poorer verbal working memory performance on the operation span task compared to control participants (n=88), but there were no group differences in visual working memory, multitasking, cognitive flexibility, attentional control, visuospatial ability, or information processing speed. Individual differences analyses revealed that time since injury and presence of memory loss predicted visual working memory capacity and visuospatial ability, respectively, in those with mTBI history. In Experiment 2, participants with mTBI history (n=20) again demonstrated poorer verbal working memory on the operation span task compared to control participants (n=38), but no group differences were revealed on a visuospatial complex span task or simpler visual working memory measures. We also explored the electrophysiological indices of visual working memory using EEG during a change detection task. No differences were observed in early sensory event-related potentials (P1, N1) or the later negative slow wave associated with visual working memory capacity. Together, these findings suggest that mTBI history may be associated with a lasting, isolated disruption in the subsystem underlying verbal working memory storage. The results emphasise the importance of sensitive cognitive measures and accounting for individual variability in injury characteristics when assessing mTBI outcomes.

Learning changes in educational animation: visuospatial working memory is more predictive than subjective task load.

Current theories suggest that visual and spatial processes in working memory are crucial for learning from animation. However, despite over three decades of research on learning from animation, little is known about how visuospatial working memory relates to learning. Instead, animation research often relies on subjective task load to explain and predict learning performance. To better understand how visuospatial working memory and learning from animation are related, a within-subjects study was conducted. Eighty six students learned from two animations of different complexity. The students' performance on visual learning tasks, visual and spatial working memory capacity, and perceived task load were assessed. Hierarchical regression analyses show that visuospatial working memory capacity is more critical for learning from a complex animation than for learning from a less complex animation. Moreover, visuospatial working memory capacity predicts learning from a complex animation significantly better than subjective task load. The effect size is large. The results provide a coherent picture of the relationships between learning task demands, learners' visuospatial working memory, perceived task load and learning performance. They not only allow for a more accurate prediction of learning from animation but can also help to tailor the design and use of animations to the learners' cognitive resources.

Maintenance and transformation of representational formats during working memory prioritization

Visual working memory depends on both material-specific brain areas in the ventral visual stream (VVS) that support the maintenance of stimulus representations and on regions in the prefrontal cortex (PFC) that control these representations. How executive control prioritizes working memory contents and whether this affects their representational formats remains an open question, however. Here, we analyzed intracranial EEG (iEEG) recordings in epilepsy patients with electrodes in VVS and PFC who performed a multi-item working memory task involving a retro-cue. We employed Representational Similarity Analysis (RSA) with various Deep Neural Network (DNN) architectures to investigate the representational format of prioritized VWM content. While recurrent DNN representations matched PFC representations in the beta band (15–29 Hz) following the retro-cue, they corresponded to VVS representations in a lower frequency range (3–14 Hz) towards the end of the maintenance period. Our findings highlight the distinct coding schemes and representational formats of prioritized content in VVS and PFC.

Persistent resampling of external information despite 25 repetitions of the same visual search templates

We commonly load visual working memory minimally when to-be-remembered information remains available in the external world. In visual search, this is characterised by participants frequently resampling previously encoded templates, which helps minimize cognitive effort and improves task performance. If all search templates have been rehearsed many times, they should become strongly represented in memory, possibly eliminating the benefit of reinspections. To test whether repetition indeed leads to less resampling, participants searched for sets of 1, 2, and 4 continuously available search templates. Critically, each unique set of templates was repeated 25 trials consecutively. Although the number of inspections and inspection durations initially decreased strongly when a template set was repeated, behaviour largely stabilised between the tenth and last repetition: Participants kept resampling templates frequently. In Experiment 2, participants performed the same task, but templates became unavailable after 15 repetitions. Strikingly, accuracy remained high even when templates could not be inspected, suggesting that resampling was not strictly necessary in later repetitions. We further show that seemingly ’excessive’ resampling behaviour had no direct within-trial benefit to speed nor accuracy, and did not improve performance on long-term memory tests. Rather, we argue that resampling was partially used to boost metacognitive confidence regarding memory representations. As such, eliminating the benefit of minimizing working memory load does not eliminate the persistence with which we sample information from the external world – although the underlying reason for resampling behaviour may be different.

Comparing representational structures for simple and complex stimuli in visual working memory

Comparing representational structures for simple and complex stimuli in visual working memory

Exploring the relationship between fluid intelligence and visual working memory for simple features vs. real-world objects

Exploring the relationship between fluid intelligence and visual working memory for simple features vs. real-world objects

Implicit prioritization of information in visual working memory?

Implicit prioritization of information in visual working memory?