Rapid Serial Visual Presentation Stream Research Articles

Attention and feature binding in the temporal domain.

Previous studies have shown that illusory conjunction can emerge for both spatially and temporally proximal objects. However, the mechanisms involved in binding in the temporal domain are not yet fully understood. In the current study, we investigated the role of attentional processes in correct and incorrect temporal binding, and specifically how feature binding is affected by the speed of attentional engagement. In two experiments, participants searched for a target in a rapid serial visual presentation stream and reported its colour and alphanumeric identity. Temporal binding errors were frequent. Critically, when participants reported the identity of a distractor instead of a target, they were also more likely to report the colour of this distractor. This association was observed both within and between individuals. These findings suggest that attentional engagement facilitates the binding of temporally co-occurring features. We discuss these results within a 'diachronic' framework of selective attention, and also consider other factors that contribute to temporal binding errors.

Expectation Modifies the Representational Fidelity of Complex Visual Objects

Abstract Prediction has been shown to play a fundamental role in facilitating efficient perception of simple visual features such as orientation and motion, but it remains unclear whether expectations modulate neural representations of more complex stimuli. Here, we addressed this issue by characterising patterns of brain activity evoked by two-dimensional images of familiar, real-world objects which were either expected or unexpected based on a preceding cue. Participants (n = 30) viewed stimuli in rapid serial visual presentation (RSVP) streams which contained both high-fidelity and degraded (diffeomorphically warped) object images. Multivariate pattern analyses of electroencephalography (EEG) data were used to quantify and compare the degree of information represented in neural activity when stimuli were random (unpredictable), expected, or unexpected. Degraded images elicited reduced representational fidelity relative to high-fidelity images. However, degraded images were represented with improved fidelity when they were presented in expected relative to random sequence positions; and stimuli in unexpected sequence positions yielded reduced representational fidelity relative to random presentations. Most notably, neural responses to unexpected stimuli contained information pertaining to the expected (but not presented) stimulus. Debriefing at the conclusion of the experiment revealed that participants were not aware of the relationship between cue and target stimuli within the RSVP streams, suggesting that the differences in stimulus decoding between conditions arose in the absence of explicit predictive knowledge. Our findings extend fundamental understanding of how the brain detects and employs predictive relationships to modulate high-level visual perception.

High target prevalence may reduce the spread of attention during search tasks.

Target prevalence influences many cognitive processes during visual search, including target detection, search efficiency, and item processing. The present research investigated whether target prevalence may also impact the spread of attention during search. Relative to low-prevalence searches, high-prevalence searches typically yield higher fixation counts, particularly during target-absent trials. This may emerge because the attention spread around each fixation may be smaller for high than low prevalence searches. To test this, observers searched for targets within object arrays in Experiments 1 (free-viewing) and 2 (gaze-contingent viewing). In Experiment 3, observers searched for targets in a Rapid Serial Visual Presentation (RSVP) stream at the center of the display while simultaneously processing occasional peripheral objects. Experiment 1 used fixation patterns to estimate attentional spread, and revealed that attention was narrowed during high, relative to low, prevalence searches. This effect was weakened during gaze-contingent search (Experiment 2) but emerged again when eye movements were unnecessary in RSVP search (Experiment 3). These results suggest that, although task demands impact how attention is allocated across displays, attention may also narrow when searching for frequent targets.

A key role of the hippocampal P3 in the attentional blink

The attentional blink (AB) refers to an impaired identification of target stimuli (T2), which are presented shortly after a prior target (T1) within a rapid serial visual presentation (RSVP) stream. It has been suggested that the AB is related to a failed transfer of T2 into working memory and that hippocampus (HC) and entorhinal cortex (EC) are regions crucial for this transfer. Since the event-related P3 component has been linked to inhibitory processes, we hypothesized that the hippocampal P3 elicited by T1 may impact on T2 processing within HC and EC. To test this hypothesis, we reanalyzed microwire data from 21 patients, who performed an RSVP task, during intracranial recordings for epilepsy surgery assessment (Reber et al., 2017). We identified T1-related hippocampal P3 components in the local field potentials (LFPs) and determined the temporal onset of T2 processing in HC/EC based on single-unit response onset activity. In accordance with our hypothesis, T1-related single-trial P3 amplitudes at the onset of T2 processing were clearly larger for unseen compared to seen T2-stimuli. Moreover, increased T1-related single-trial P3 peak latencies were found for T2[unseen] versus T2[seen] trials in case of lags 1 to 3, which was in line with our predictions. In conclusion, our findings support inhibition models of the AB and indicate that the hippocampal P3 elicited by T1 plays a central role in the AB.

The temporal dynamics of selective attention are reflected by distractor intrusions

When observers have to identify an object embedded in a rapid serial visual presentation (RSVP) stream, they often erroneously report the identity of a distractor instead of the target (distractor intrusion). In two experiments, we examined whether these intrusion errors are associated with the speed of attentional engagement. Participants reported the identity of target digits indicated by shape selection cues. To manipulate the speed of engagement, targets appeared either within a single RSVP stream or unpredictably in one of two streams. Objects that followed the selection cue were reported more frequently when engagement was delayed (two streams), whereas the probability of reporting objects preceding the cue was higher when engagement was faster (single stream). These results show that distractor intrusions are closely linked to the allocation of selective attention in time, making the intrusion paradigm a useful tool for research into the temporal dynamics of attention. They also provide new evidence for the idea that attentional selectivity operates within brief periods of perceptual enhancement (attentional episodes), facilitating the processing of all objects within this period, regardless of their status as targets or distractors.

Both target detection and response contribute to the attentional boost effect.

Detecting and responding to targets in an rapid serial visual presentation (RSVP) stream facilitates the processing of concurrently presented images. Theoretical accounts of this attentional boost effect (ABE) have emphasized the role of target detection, yet it is unclear whether the ABE originates from target detection or response. To examine this, we asked participants to search for the letter T among a rapid stream of other letters while encoding objects to memory. The nontarget letters, drawn randomly from the remaining letters of the Roman alphabet, comprised half of the trials. Across three experiments, participants responded only to the target letter T, to all letters but the target letter T, or to both T and not-T with two different keys. The large number of different nontargets ensured that participants preferred to search for the target letter T regardless of the response requirement. We found an ABE when participants responded to the target letter T, but not when they responded to the other nontarget letters, suggesting that response requirement modulated the ABE. Furthermore, making different responses to targets and nontargets led to a memory advantage for target-paired objects. Thus, target detection and response both contributed to the ABE. (PsycInfo Database Record (c) 2022 APA, all rights reserved).

The attentional boost effect facilitates visual category learning.

Increasing evidence has shown that summary visual statistics, such as the mean size or centroid of locations, can be perceived without focal attention. Here, we tested the role of attention in visual category learning - rapid learning of visual similarities among paintings of the same artist. Participants encoded paintings from two famous artists into memory while simultaneously monitoring a rapid serial visual presentation (RSVP) stream of colored squares, pressing the spacebar for target colors and making no response to distractor colors. Paintings encoded with the RSVP targets were better remembered than those encoded with the RSVP distractors, demonstrating an Attentional Boost Effect. Importantly, pairing one artist's paintings with the RSVP targets led to better visual category learning - participants were more accurate at recognizing novel paintings from this artist, relative to another artist whose paintings were presented with the RSVP distractors. Thus, visual category learning is subjected to the same constraint of attention as exemplar memory, demonstrating common mechanisms for exemplar and category learning.

Habituation to emotional distractors attenuates emotion-induced blindness.

Recent research has shown that emotion-induced blindness (EIB) can be attenuated by strengthening the attentional prioritization of perceptual targets in the rapid serial visual presentation stream and/or proactively inhibiting emotional distractors. However, whether EIB can be attenuated by reducing the attentional prioritization of emotional distractors through passive habituation remains unknown. To address this question, the present experiment utilized a novel three-session paradigm including a pre- and post-EIB measurement session and an intermediate multiblock free-view habituation session. In order to examine the effectivity and specificity of the habituation effect on EIB, four groups of participants underwent the same pre- and post-EIB measurement session but completed the habituation session with different kinds of pictures: (a) repeated negative pictures, which were seen in pre-EIB; (b) repeated neutral pictures, which were seen in pre-EIB; (c) novel negative pictures, which were never seen in pre-EIB; and (d) novel neutral pictures, which were never seen in pre-EIB. The results showed that the EIB effect was only significantly attenuated after habituation to repeated negative pictures. This finding indicates that emotional interference in EIB can be attenuated by reducing the attentional prioritization of emotional distractors through habituation. Furthermore, similar EIB attenuation after habituation to repeated neutral pictures suggests that the habituation-induced attenuation might be context specific. These results provide a potentially new and important approach to reduce EIB effects. (PsycInfo Database Record (c) 2022 APA, all rights reserved).

Frequency‐ and phase‐dependent effects of auditory entrainment on attentional blink

Attentional blink (AB) is the impaired detection of a second target (T2) after a first target has been identified. In this paper, we investigated the functional roles of alpha and theta oscillations on AB by determining how much preceding rhythmic auditory stimulation affected the performance of AB. Healthy young adults participated in the experiment online. We found that when two targets were embedded in rapid serial visual presentation (RSVP) of distractors at 10Hz (i.e., alpha frequency), the magnitude of AB increased with auditory stimuli. The increase was limited to the case when the frequency and phase of auditory stimuli matched the following RSVP stream. On the contrary, when only two targets were presented without distractors, auditory stimuli at theta, not alpha, increased the AB magnitude. These results indicate that neural oscillations at two different frequencies, namely, alpha and theta, are involved in attentional blink.

Expectation-based blindness: Predictions about object categories gate awareness of focally attended objects.

Selective attention gates access to conscious awareness, resulting in surprising failures to notice clearly visible but unattended objects ('inattentional blindness'). Here, we demonstrate that expectations can have a similar effect, even for fully attended objects ('expectation-based blindness'). In three experiments, participants (N = 613) were presented with rapid serial visual presentation (RSVP) streams at fixation and had to identify a target object indicated by a cue. Target category was repeated for the first 19 trials but unexpectedly changed on trial 20. The probability of correct target reports on this surprise trial was substantially lower than on preceding and subsequent trials. This impairment was present for switches between target letters and digits, and also for changes between human and animal face images. In contrast, no drop in accuracy was observed for novel target objects from the same category as previous targets. These results demonstrate that predictions about object categories affect visual awareness. Objects that are task relevant and focally attended often fail to get noticed when their category changes unexpectedly.

The location independence of learned attentional flexibility.

Individuals can adjust their shift readiness, known as attentional flexibility, according to the statistical structure of the environment. However, the extent to which these modulations in attentional flexibility are associated with a global readiness to shift attention to any location versus an anticipated shift to a single location remains unknown. Across two experiments, participants shifted attention among three rapid serial visual presentation (RSVP) streams of alphanumeric characters in response to embedded visual cues and made button presses in response to targets at the cued location. We manipulated the likelihood that participants would receive a cue that signaled a shift between two of the streams across blocks of trials. The likelihood of a cued shift of attention to the third location was held constant across all blocks. Participants demonstrated smaller target detection shift costs (Experiments 1 and 2) and shorter saccade latencies (Experiment 1) when the overall likelihood of shifting was high than when the overall shift likelihood was low. Critically, we observed evidence of both global shift readiness and location-specific shift readiness in both experiments such that participants shifted attention to the most-likely-to-be cued location the fastest, but still demonstrated a difference in the time to shift attention to the unlikely location according to the overall shift likelihood. Our findings provide evidence that moment-by-moment changes in attentional flexibility are not limited to an expectation to shift to a single location, but rather reflect, in part, a location-independent state of control.

Effects of Temporal Characteristics on Pilots Perceiving Audiovisual Warning Signals Under Different Perceptual Loads.

Our research aimed to investigate the effectiveness of auditory, visual, and audiovisual warning signals for capturing the attention of the pilot, and how stimulus onset asynchronies (SOA) in audiovisual stimuli affect pilots perceiving the bimodal warning signals under different perceptual load conditions. In experiment 1 of the low perceptual load condition, participants discriminated the location (right vs. left) of visual targets preceded by five different types of warning signals. In experiment 2 of high perceptual load, participants completed the location task identical to a low load condition and a digit detection task in a rapid serial visual presentation (RSVP) stream. The main effect of warning signals in two experiments showed that visual and auditory cues presented simultaneously (AV) could effectively and efficiently arouse the attention of the pilots in high and low load conditions. Specifically, auditory (A), AV, and visual preceding auditory stimulus by 100 ms (VA100) increased the spatial orientation to a valid position in low load conditions. With the increase in visual perceptual load, auditory preceding the visual stimulus by 100 ms (AV100) and A warning signals had stronger spatial orientation. The results are expected to theoretically support the optimization design of the cockpit display interface, contributing to immediate flight crew awareness.

Task demands determine whether shape or arousal of a stimulus modulates competition for visual working memory resources

It has been posited (Öhman, 1986) that the processing of threatening stimuli became prioritized during the course of mammalian evolution and that such objects may still enjoy an advantage in visual processing to this day. It has been well-documented that both mid-level visual features (i.e., conjunctions of low-level features) and the arousal level of threatening stimuli affect attentional allocation (Cisler & Koster, 2010; Wolfe & Horowitz, 2004). Despite this, few studies have investigated the effect these factors have on visual working memory resources. Here, we investigated these factors using a rapid serial visual presentation (RSVP) paradigm, and by manipulating mid-level features (specifically, shape: similar vs. dissimilar) and the arousal level (non-threatening vs threatening) of the stimuli. Participants watched an RSVP stream in preparation for an upcoming memory test. Then, they completed a two-alternative forced-choice recognition memory test (with semantically matched foils) wherein they had to identify which item they had seen in the RSVP stream. Our results showed that when shape was a sufficient feature to discriminate the target from the other items in the stream, there was no effect of arousal (i.e., threat level) on reaction time or accuracy during the memory test. However, when the shapes of all the stimuli in the visual stream were highly similar, an effect of arousal appeared: When the target had a different arousal level than the background items (i.e., non-targets), performance was improved. Together, the results suggest that both mid-level visual features and arousal level can modulate competition for visual working memory resources.

Human EEG recordings for 1,854 concepts presented in rapid serial visual presentation streams

The neural basis of object recognition and semantic knowledge has been extensively studied but the high dimensionality of object space makes it challenging to develop overarching theories on how the brain organises object knowledge. To help understand how the brain allows us to recognise, categorise, and represent objects and object categories, there is a growing interest in using large-scale image databases for neuroimaging experiments. In the current paper, we present THINGS-EEG, a dataset containing human electroencephalography responses from 50 subjects to 1,854 object concepts and 22,248 images in the THINGS stimulus set, a manually curated and high-quality image database that was specifically designed for studying human vision. The THINGS-EEG dataset provides neuroimaging recordings to a systematic collection of objects and concepts and can therefore support a wide array of research to understand visual object processing in the human brain.

Response, rather than target detection, triggers the attentional boost effect in visual search.

Detecting a target in a rapid serial visual presentation (RSVP) stream is more attentionally demanding than rejecting a distractor. However, background scenes coinciding with RSVP targets are better remembered than those coinciding with RSVP distractors, a paradoxical finding known as the attentional boost effect. But does the effect originate from the detection of the RSVP target or from the need to respond to it? To dissociate target detection from response, we investigated the attentional boost effect using a visual search task. Participants searched for a target among distractors while memorizing concurrently presented background objects. The search target could be present or absent. In different experiments, participants pressed a button on target-present trials only, target-absent trials only, or made a two-choice present/absent response. Results showed that objects paired with a Go response were better remembered than objects paired with a No-Go response, regardless of whether responses were associated with target-present or target-absent trials. This finding was replicated in experiments that required covert counting rather than an immediate button press response. These findings are the first to extend the attentional boost effect to visual search and demonstrate that the need to respond, not the detection of a search target, drives the effect for concurrently presented stimuli. (PsycInfo Database Record (c) 2022 APA, all rights reserved).

Attention to a Moment in Time Impairs Episodic Distinctiveness during Rapid Serial Visual Presentation

Human attention is limited in the ability to select and segregate relevant distinct events from the continuous flow of external information while concurrently encoding their temporal succession. While it is well-known that orienting attention to one external target stimulus impairs the encoding of ensuing relevant external events, it is still unknown whether orienting attention to internally generated events can interfere with concurrent processing of external input. We addressed this issue by asking participants to identify a single target embedded among distractors in a non-spatial rapid serial visual presentation (RSVP) stream and to indicate whether that target appeared before or after an internally estimated midpoint of the stream. The results indicate that (a) such an internally generated temporal benchmark does not interfere with the identification of a subsequent physical target stimulus but (b) the two events cannot be accurately segregated when the physical target immediately follows the internally generated temporal event. These findings indicate that the asymmetrical distribution around the midpoint of order reversals reflects an impaired temporal discrimination ability. Orienting attention to a moment in time reduces episodic distinctiveness as much as orienting attention to external events.

The effect of visual statistical learning in RSVP: Implicit learning or stream location artifact?

Visual statistical learning (VSL) occurs when participants are exposed to spatially or temporally ordered stimuli, and become increasingly sensitive to them without explicitly realizing the hidden regularities. In the temporal domain of VSL, participants are usually exposed to shape-triplets, followed by the use of familiarity judgments and recognition tasks to directly probe VSL. Other methods, such as the rapid serial visual presentation (RSVP) task, indirectly probe the learning of temporal sequences, and provide evidence of learning within the triplets. Despite the RSVP's success, however, previous implementations of the RSVP task have only pseudorandomized the triplets to form the test sequence, such that the task permits only two stream locations for a given target shape (belonging to a certain within-triplet position), out of six available locations. These fixed locations may result in confounded response time (RT) findings and potentially lead to an overestimation of a weak (or nonexistent) VSL effect. In this study, we conduct 4 experiments and show that the previously reported VSL effect in RSVP is eliminated when the RSVP stream is fully counterbalanced (Experiment 1), and resurfaces again when the RSVP stream returns to its original pseudorandomized design (Experiment 2). Importantly, in both, we observe a "stream location effect," where RT gradually becomes faster to reflect the hazard rate of target appearance, which may have been the factor driving previously reported VSL effects. Follow-up experiments show that results from Experiment 1 are not due to the absence of implicit learning (Experiment 3), although the stream location effect can occur without any learning, suggesting that it is something inherent to the RSVP task (Experiment 4). Together, these results identify an influential effect, the stream location effect, inherently present in the RSVP task, and show how misinforming the RSVP task can be, when not used with properly controlled parameters, and demand a reexamination of the effects found in previous studies which could have been the effect of detection stream locations, misconstrued as VSL. (PsycInfo Database Record (c) 2021 APA, all rights reserved).

Emotional content overrides spatial attention.

Spatial attention is our capacity to attend to or ignore particular regions of our spatial environment. However, some classes of stimuli may be able to override our efforts to ignore them. Here we assessed the relationship between involuntary attentional capture with emotional images and spatial attention at early stages of perceptual processing. Multiple scenes of unpleasant and neutral content were displayed in rapid serial visual presentation (RSVP) streams that elicited the steady-state visual evoked potential (SSVEP), a neural marker of selective attention at early visual areas. In a spatial cueing task, participants were cued to covertly attend to RSVP streams presented at 4 and 6Hz presentation rates in the left and right visual hemifields. The task was to detect square targets occasionally displayed within the image streams, responding only to those appearing on the cued side. The RSVP streams were always neutral pictures in one visual hemifield but would unpredictably switch from neutral to aversive content in the other visual hemifield. We found that SSVEP amplitude was consistently modulated by a change in emotional valence of image streams, regardless of whether the change in content occurred in the attended or unattended spatial location, reflecting an automatic sensory amplification for affective stimuli. The present data provide further evidence in support that emotional images can attract visual processing resources independently of spatial attention allocation, and are consistent with sustained sensory facilitation of early visual areas through re-entrant feedback projections from higher-order cortical areas involved in the extraction of affective information.

Nontarget emotional stimuli must be highly conspicuous to modulate the attentional blink.

The attentional blink (AB) is often considered a top-down phenomenon because it is triggered by matching an initial target (T1) in a rapid serial visual presentation (RSVP) stream to a search template. However, the AB is modulated when targets are emotional, and is evoked when a task-irrelevant, emotional critical distractor (CDI) replaces T1. Neither manipulation fully captures the interplay between bottom-up and top-down attention in the AB: Valenced targets intrinsically conflate top-down and bottom-up attention. The CDI approach cannot manipulate second target (T2) valence, which is critical because valenced T2s can “break through” the AB (in the target-manipulation approach). The present research resolves this methodological challenge by indirectly measuring whether a purely bottom-up CDI can modulate report of a subsequent T2. This novel approach adds a valenced CDI to the “classic,” two-target AB. Participants viewed RSVP streams containing a T1–CDI pair preceding a variable lag to T2. If the CDI’s valence is sufficient to survive the AB, it should modulate T2 performance, indirectly signaling bottom-up capture by an emotional stimulus. Contrary to this prediction, CDI valence only affected the AB when CDIs were also extremely visually conspicuous. Thus, emotional valence alone is insufficient to modulate the AB.

Modeling the attentional blink: A simple logistic model with first-order difference system

The attentional blink (AB) basically refers to a deficit in the processing of the second stimulus, which is revealed when two target stimuli are presented in a rapid serial visual presentation (RSVP) stream. We propose a mathematical model of the AB based on a logistic model with first-order difference system, and give a maximum likelihood method for estimating the parameters of our model. Validity of the model is confirmed by using numerical examples and simulating some typical phenomena on the AB.