Probing memory of a complex visual image within a few hundred milliseconds after its disappearance reveals significantly greater fidelity of recall than if the probe is delayed by as little as a ...second. Classically interpreted, the former taps into a detailed but rapidly decaying visual sensory or 'iconic' memory (IM), while the latter relies on capacity-limited but comparatively stable visual working memory (VWM). While iconic decay and VWM capacity have been extensively studied independently, currently no single framework quantitatively accounts for the dynamics of memory fidelity over these time scales. Here, we extend a stationary neural population model of VWM with a temporal dimension, incorporating rapid sensory-driven accumulation of activity encoding each visual feature in memory, and a slower accumulation of internal error that causes memorized features to randomly drift over time. Instead of facilitating read-out from an independent sensory store, an early cue benefits recall by lifting the effective limit on VWM signal strength imposed when multiple items compete for representation, allowing memory for the cued item to be supplemented with information from the decaying sensory trace. Empirical measurements of human recall dynamics validate these predictions while excluding alternative model architectures. A key conclusion is that differences in capacity classically thought to distinguish IM and VWM are in fact contingent upon a single resource-limited WM store.
Population coding models provide a quantitative account of visual working memory (VWM) retrieval errors with a plausible link to the response characteristics of sensory neurons. Recent work has ...provided an important new perspective linking population coding to variables of signal detection, including d-prime, and put forward a new hypothesis: that the distribution of recall errors on, for example, a color wheel, is a consequence of the psychological similarity between points in that stimulus space, such that the exponential-like psychophysical distance scaling function can fulfil the role of population tuning and obviate the need to fit a tuning width parameter to recall data. Using four different visual feature spaces, we measured psychophysical similarity and memory errors in the same participants. Our results revealed strong evidence for a common source of variability affecting similarity judgments and recall estimates but did not support any consistent relationship between psychophysical similarity functions and VWM errors. At the group level, the responsiveness functions obtained from the psychophysical similarity task diverged strongly from those that provided the best fit to working memory errors. At the individual level, we found convincing evidence against an association between observed and best-fitting similarity functions. Finally, our results show that the newly proposed exponential-like responsiveness function has in general no advantage over the canonical von Mises (circular normal) function assumed by previous population coding models.
Vidno radno pamćenje (VRP) skupni je naziv za procese kratkotrajnog zadržavanja vidnih informacija s ciljem trenutnog obavljanja zadatka. Posljednjih su desetak godina istraživanja u području ...rezultirala brojnim revolucionarnim, kako bihevioralnim, tako i neurološkim, nalazima koji su znatno promijenili načine na koje danas promatramo VRP. Ovim su pregledom obuhvaćene neke najvažnije teorijske ideje i nalazi koji su definirali istraživačke smjerove unutar područja. Rad započinjemo kratkim smještanjem VRP-a u kontekst srodnih kognitivnih procesa. Nakon prikaza najčešćih zadataka korištenih u istraživanjima VRP-a, središnji je dio rada posvećen prikazu dviju dominantnih teorija VRP-a i njihovoj usporedbi – modelima utora i modelima resursa. Nakon gotovo četrdeset godina empirijske podrške modelima utora, brojna istraživanja, objedinjena modelima resursa, revidiraju naša znanja o VRP-a. Kako bismo zaključili pitanje arhitekture reprezentacija VRP-a, dan je pregled istraživanja koja su pokušala odgovoriti na pitanje jesu li reprezentacije VRP-a sastavljene od pojedinačnih vidnih svojstava ili već integriranih objekata. Kako ni jedan od pristupa ne može u potpunosti objasniti rezultate istraživanja, najizgledniji se odgovor na pitanje o jedinicama kodiranja nalazi u hijerarhijskim modelima koji pretpostavljaju kako vidne informacije kodiramo i na razini svojstava, ali i na razini integriranih objekata. U drugom su dijelu rada opisane tri bitne komponente funkcioniranja VRP-a: usvajanje, dosjećanje i zaboravljanje informacija. Područja istraživanja ovih komponenata obilježena su provjerama relativno suprotstavljenih modela te metodološkim novinama uvedenima kako bi se na što obuhvatniji način ispitale postojeće hipoteze.
Visual working memory (VWM) is an umbrella term for processes of short-term retention and manipulation of visual information which support performance in an ongoing task. In the last decade studies in the field resulted in numerous revolutionary, both behavioural and neuropsychological, findings that have changed our understanding of VWM.
In this review, we discuss some of the most important theoretical ideas
and findings that have defined research orientations in the field. We begin this paper with placing VWM in the context of similar cognitive processes. After describing the most commonly used tasks in the studies of VWM, in the body of this paper we are reviewing two dominant theories
of VWM - slot models and resource models of VWM. After almost forty years of empirical support of slot models, recent studies conducted under resource models paradigm are reappraising our knowledge about VWM.
In order to conclude the section on VWM architecture, we review studies
that aimed to answer the question whether the VWM representations are comprised of specific visual features or already integrated objects. Since the two opposing approaches cannot completely explain existing findings, the most promising approach is the one which suggests a hierarchical model of encoding, both at the level of features and integrated objects. In the second part of the paper, we review three main tasks of VWM: encoding, retrieval, and forgetting of the information. Fields of studying these components are marked with verification of clearly opposing models, along with methodological innovations proposed in order to thoroughly examine those models. Here, we review them with an aim to elucidate the nature of core VWM components.
Memoria de trabajo visual (MTV) es el denominador común para todos los procesos de retención a corto plazo de informaciones visuales con el objetivo de realizar al instante una tarea. En los últimos diez años las investigaciones en este campo han dado como resultado muchos hallazgos revolucionarios, sea conductuales o neurológicos, que han cambiado significativamente los modos en los que hoy consideramos MTV. Esta revisión abarca algunas de las ideas teóricas y los hallazgos más importantes, que han definido direcciones de investigación dentro del campo. Empezamos el trabajo situando en breve MTV, mientras que la parte central está dedicada a presentar dos teorías dominantes de MTV y compararlas – el modelo de la muesca y el modelo de recursos. Después de casi cuarenta años de apoyar empíricamente los modelos de muesca, numerosas investigaciones, unidas en los modelos de recursos, hacen una revisión de nuestros conocimientos sobre MTV. Para concluir la cuestión de arquitectura de las representaciones de MTV, se ofrece la presentación de las investigaciones que han intentado responder a la pregunta si las representaciones de MTV constan de características visuales individuales u objetos ya integrados. Como ninguno de los enfoques no puede explicar completamente los resultados de las investigaciones, la respuesta más probable en cuanto a las unidades de codificación está en los modelos jerárquicos que presuponen que codificamos las informaciones visuales tanto en el nivel de características, como en el nivel de objetos integrados. En la segunda parte del trabajo se han descrito tres componentes importantes del funcionamiento de MTV: adoptar, recordar y olvidar informaciones. Los campos de investigación de estos componentes están marcados por las pruebas de modelos relativamente confrontados y por las novedades metodológicas introducidas con el fin de examinar las hipótesis existentes cuanto más exhaustivo.
Visual working memory (VWM) resources are limited, placing constraints on how much visual information can be simultaneously retained. During visually guided activity, stored information can quickly ...become outdated, so updating mechanisms are needed to ensure the contents of memory remain relevant to current task goals. In particular, successful deallocation of resources from items that become obsolete is likely to be critical for maintaining the precision of those representations still in memory. The experiments in this study involved presenting two memory arrays of coloured disks in sequence. The appearance of the second array was a cue to replace, rehearse, or add a new colour to the colours in memory. We predicted that successful resource reallocation should result in comparable recall precision when an item was replaced or rehearsed, owing to the removal of pre-replacement features. In contrast, a failure to update WM should lead to comparable precision with a condition in which a new colour was added to memory. We identified a very small proportion (∼5%) of trials in which participants incorrectly reported a feature from the first array in place of its replacement in the second, which we interpreted as a failure to incorporate the information from the second display into memory. Once these trials were discounted, precision estimates were consistent with complete redistribution of resources in the case of updating a single item. We conclude that working memory can be efficiently updated when previous information becomes obsolete, but that this is a demanding active process that occasionally fails.
Acute pain sensation is an inherently negative but adaptive experience; however, research on pain sensitivity shows that simple contextual cues can effectively attenuate the pain. In this study, we ...sought to investigate how dominance cues, manipulated as vertical spatial (i.e., height) distance between participants and experimenter, affect participants’ pain sensitivity. Positioning participants in a spatially higher position relative to the experimenter was aimed to induce a feeling of dominance in participants. Conversely, a feeling of submissiveness was induced by placing the experimenter in a spatially higher position. In addition, we examined the role of dominance cues with respect to participants’ and experimenters’ gender. Two separate studies were conducted—Study 1 with a male experimenter measuring pain threshold in female and male participants (N = 137), and Study 2 with a female experimenter conducting pain measurement in a new sample of female and male participants (N = 122). The results of both studies demonstrated that participants in a dominant position reported a higher pain threshold relative to participants in a submissive position. Male participants had a higher pain threshold in both studies; however, Study 1 revealed a significant interaction of dominance manipulation and participant’s gender, with the effect of dominance cues being larger in men.
The precision with which visual information can be recalled from working memory declines as the number of items in memory increases. This finding has been explained in terms of the distribution of a ...limited representational resource between items. Here we investigated how the sensory strength of memoranda affects resource allocation. We manipulated signal strength of an orientation stimulus in two ways: we varied the internal (sensory) noise by adjusting stimulus contrast, and varied the external (stimulus) noise by altering the within-stimulus variability. Both manipulations had similar effects on the precision with which the orientation could be recalled, but differed in their impact on memory for other stimuli. These results indicate that increasing internal noise released resources that could be used to store other stimuli more precisely; increasing external noise had no such effect. We show that these observations can be captured by a simple neural model of working memory encoding, in which spiking activity takes on the role of the limited resource.
Jedan je od glavnih zadataka vidnoga radnog pamćenja (VRP) zaštita pohranjenih sadržaja od nevažnih vidnih podražaja u okolini, tj. od distraktirajućih informacija. Iako velik broj istraživanja ...pokazuje negativan utjecaj distraktora na sadržaje u VRP-u, nejasno je utječu li distraktori jednako na VRP u različitim fazama obrade, tj. tijekom kodiranja, zadržavanja i dosjećanja. U provedenome su istraživanju sudionici (N = 12) u zadatku VRP-a pamtili obojene podražaje te su im prikazivani perceptivni distraktori u različitim fazama obrade podražaja. Rezultati su pokazali da prikazivanje distraktora neposredno nakon nestanka podražaja za pamćenje (tj. u fazi kodiranja), ali ne i tijekom faze zadržavanja ili dosjećanja, dovodi do porasta pogreške dosjećanja. Ključno, utjecaj distraktora nije ovisio o njihovoj snazi manipuliranoj kao trajanje prikaza distraktora. Da bismo pobliže istražili vrstu pogreške do koje dolazi uslijed prikaza distraktora, podaci su procijenjeni probabilističkim modelom mješovitih distribucija. Rezultati su pokazali da se porast pogreške dosjećanja dominantno može pripisati porastu pogrešaka zamjena i pogreškama intruzije, dok pogreške slučajnoga pogađanja te preciznost točnih dosjećanja nisu pokazali sustavno variranje s prikazom distraktora. Naši rezultati pokazuju da je proces obrane od distraktora u VRP-u pretežno uspješan, s povremenim neuspjesima koji rezultiraju jasnim obrascima pogrešaka. Konačno, ti rezultati govore u prilog distribuiranoj pohrani sadržaja VRP-a i suprotni su pretpostavkama hipoteze senzornoga kodiranja.
One of the main tasks of visual working memory (VWM) is to protect stored contents from irrelevant visual stimuli in the environment, i.e., distracting information. Although a large number of studies demonstrates a detrimental effect of distractors on VWM content, it is less clear whether distractors affect VWM equally at different processing phases, e.g., during encoding, maintenance, and retrieval. In this study, observers (N = 12) memorized coloured stimuli in a VWM task, and were subsequently presented with perceptual distractors in different phases of stimuli processing. The results have shown that presenting distractors immediately after the disappearance of a memory array (i.e., during the encoding), but not during the maintenance or retrieval phase, increases recall error. Critically, this did not depend on distractors’ strength manipulated as their presentation time. To further investigate the type of error that occurs following distractor presentation, we fit a probabilistic mixture model to the data. The results have shown that the observed increase in recall error can be predominantly attributed to the increase in swap and intrusion errors, while guesses and the precision of correct recalls were not affected by distractor presentation. Our results demonstrate that VWM can successfully protect its content from distractors, however, with occasional failures resulting in clear error patterns. Finally, these results provide evidence for a distributed storage of VWM, in contrast to the sensory recruitment hypothesis.
The use of sexually explicit material (SEM) has become a part of adolescent sexual socialization, at least in the Western world. Adolescent and young people’s SEM use has been associated with risky ...sexual behaviors, which has recently resulted in policy debates about restricting access to SEM. Such development seems to suggest a crisis of the preventive role of parental oversight. Based on the Differential Susceptibility to Media Effects Model, this study assessed the role of parental monitoring in the context of adolescent vulnerability to SEM-associated risky or potentially adverse outcomes (sexual activity, sexual aggressiveness, and sexting). Using an online sample of Croatian 16-year-olds (
N
= 1265) and structural equation modeling approach, parental monitoring was found consistently and negatively related to the problematic behavioral outcomes, regardless of participants’ gender. While SEM use was related to sexual experience and sexting, higher levels of parental monitoring were associated with less frequent SEM use and lower acceptance of sexual permissiveness. Despite parents’ fears about losing the ability to monitor their adolescent children’s lives in the Internet era, there is evidence that parental engagement remains an important protective factor.
In cue-based recall from working memory, incorrectly reporting features of an uncued item may be referred to as a “swap” error. One account of these errors ascribes them to variability in memory for ...the cue features leading to erroneous selection of a non-target item, especially if it is similar to the target in the cue-feature dimension. However, alternative accounts of swap errors include cue-independent misbinding, and strategic guessing when the cued item is not in memory. Here we investigated the cause of swap errors by manipulating the variability with which either cue or report features (orientations in Exp 1; motion directions in Exp 2) were encoded. We found that swap errors increased with increasing variability in memory for the cue features, and their changing frequency could be quantitatively predicted based on recall variability when the same feature was used for report. These results are inconsistent with the hypothesis that swaps are a strategic response to forgotten items, and suggest that swap errors could be wholly accounted for by confusions due to cue-dimension variability. In a third experiment we examined whether spatial configuration of memory arrays in tasks with spatial cueing has an influence on swap error frequency. We observed a specific tendency to make swap errors to non-targets located precisely opposite to the cued location, suggesting that stimulus positions are partially encoded in a non-metric format.
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