Set Of Stimuli Research Articles

The sound of silence: Reconsidering infants' object categorization in silence, with labels, and with nonlinguistic sounds

A large body of research based on a specific stimulus set (dinosaur/fish) has argued that auditory labels and novel communicative signals (such as beeps used in a communicative context) facilitate category formation in infants, that such effects can be attributed to the auditory signals' communicative nature, and that other auditory stimuli have no effect on categorization. A contrasting view, the auditory overshadowing hypothesis, maintains that auditory signals disrupt processing of visual information and, therefore, interfere with categorization, with more unfamiliar sounds having a more disruptive effect than familiar ones. Here, we used the dinosaur/fish stimulus set to test these contrasting theories in two experiments. In Experiment 1 (N = 17), we found that 6-month-old infants were able to form categories of these stimuli in silence, weakening the claim that labels facilitated their categorization in infants. These results imply that prior findings of no categorization of these stimuli in the presence of nonlinguistic sounds must be due to disruptive effects of such sounds. In Experiment 2 (N = 17), we showed that familiarity modulated the disruptive effect of nonlinguistic sounds on infants' categorization of these stimuli. Together, these results support the auditory overshadowing hypothesis and provide new insights into the interaction between visual and auditory information in infants' category formation.

Backward masking reveals coarse-to-fine dynamics in human V1

Natural images exhibit luminance variations aligned across a broad spectrum of spatial frequencies (SFs). It has been proposed that, at early stages of processing, the coarse signals carried by the low SF (LSF) of the visual input are sent rapidly from primary visual cortex (V1) to ventral, dorsal and frontal regions to form a coarse representation of the input, which is later sent back to V1 to guide the processing of fine-grained high SFs (i.e., HSF). We used functional resonance imaging (fMRI) to investigate the role of human V1 in the coarse-to-fine integration of visual input. We disrupted the processing of the coarse and fine content of full-spectrum human face stimuli via backward masking of selective SF ranges (LSFs: <1.75cpd and HSFs: >1.75cpd) at specific times (50, 83, 100 or 150 ms). In line with coarse-to-fine proposals, we found that (1) the selective masking of stimulus LSF disrupted V1 activity in the earliest time window, and progressively decreased in influence, while (2) an opposite trend was observed for the masking of stimulus’ HSF. This pattern of activity was found in V1, as well as in ventral (i.e. the Fusiform Face area, FFA), dorsal and orbitofrontal regions. We additionally presented subjects with contrast negated stimuli. While contrast negation significantly reduced response amplitudes in the FFA, as well as coupling between FFA and V1, coarse-to-fine dynamics were not affected by this manipulation. The fact that V1 response dynamics to strictly identical stimulus sets differed depending on the masked scale adds to growing evidence that V1 role goes beyond the early and quasi-passive transmission of visual information to the rest of the brain. It instead indicates that V1 may yield a ‘spatially registered common forum’ or ‘blackboard’ that integrates top-down inferences with incoming visual signals through its recurrent interaction with high-level regions located in the inferotemporal, dorsal and frontal regions.

The features underlying the memorability of objects.

What makes certain images more memorable than others? While much of memory research has focused on participant effects, recent studies using a stimulus-centric perspective have sparked debate on the determinants of memory, including the roles of semantic and visual features and whether the most prototypical or atypical items are best remembered. Prior studies have typically relied on constrained stimulus sets, limiting a generalized view of the features underlying what we remember. Here, we collected more than 1 million memory ratings for a naturalistic dataset of 26,107 object images designed to comprehensively sample concrete objects. We establish a model of object features that is predictive of image memorability and examined whether memorability could be accounted for by the typicality of the objects. We find that semantic features exert a stronger influence than perceptual features on what we remember and that the relationship between memorability and typicality is more complex than a simple positive or negative association alone.

A preliminary investigation to establish conceptual behavior in gray wolves (Canis lupus).

Conceptual behavior represents a type of complex stimulus control where an organism differentially responds to examples and nonexamples of instances within a stimulus class. Different species have demonstrated conceptual behavior both in their natural environments and through experimental investigations. The current paper investigates preliminary methods to teach conceptual behavior to gray wolves (Canis lupus). The researchers used a match-to-sample arrangement to teach three shapes: a triangle, square, and cross varying in size, color, and positions. Probe trials used a novel set of stimuli to test for the emergence of conceptual behavior. Although the wolves did not show an immediate transfer to novel stimuli following initial match-to-sample training, they did show improvement after explicit discrimination training. We discuss the implications of these results as well as future methods that may enhance experimental procedures investigating concept learning in canids.

Learning a Model of Shape Selectivity in V4 Cells Reveals Shape Encoding Mechanisms in the Brain.

The mechanisms involved in transforming early visual signals to curvature representations in V4 are unknown. We propose a hierarchical model that reveals V1/V2 encodings that are essential components for this transformation to the reported curvature representations in V4. Then, by relaxing the often-imposed prior of a single Gaussian, V4 shape selectivity is learned in the last layer of the hierarchy from Macaque V4 responses. We found that V4 cells integrate multiple shape parts from the full spatial extent of their receptive fields with similar excitatory and inhibitory contributions. Our results uncover new details in existing data about shape selectivity in V4 neurons that with additional experiments can enhance our understanding of processing in this area. Accordingly, we propose designs for a stimulus set that allow removing shape parts without disturbing the curvature signal to isolate part contributions to V4 responses.SIGNIFICANCE STATEMENT Selectivity to convex and concave shape parts in V4 neurons has been repeatedly reported. Nonetheless, the mechanisms that yield such selectivities in the ventral stream remain unknown. We propose a hierarchical computational model that incorporates findings of the various visual areas involved in shape processing and suggest mechanisms that transform the shape signal from low-level features to convex/concave part representations. Learning shape selectivity from Macaque V4 responses in the final processing stage in our model, we found that V4 neurons integrate shape parts from the full spatial extent of their receptive field with both facilitatory and inhibitory contributions. These results reveal hidden information in existing V4 data that with additional experiments can enhance our understanding of processing in V4.

A Comparison of Stimulus Set Sizes: Systematic Replication with Operant Analysis Acquisition Criteria.

We conducted a systematic replication of Kodak et al.'s Journal of Applied Behavior Analysis, 53(1), 265-283 (2020) and Vladescu et al.'s Behavior Analysis in Practice, 14(1), 193-197 (2021) experiments on the effects of stimulus set sizes on skill acquisition. The researchers manipulated the stimulus set sizes by teaching 3, 6, and 12 sight words simultaneously during learn unit instruction. Researchers taught participants until the participant's responding reached the acquisition criterion for 12 different sight words per set size condition. The acquisition criterion was set for an individual operant, whereby when accuracy met criterion for a single sight word, that sight word was replaced in the following session. The results showed that the set-size-3 was more efficient in producing criterion-level responding during acquisition than the set-size-6, and -12, which was consistent with Vladescu et al.'s findings. However, the set-size-12 reliably produced the highest maintenance levels for all participants. The definition of "effectiveness" based on acquisition or maintenance was discussed.

284. Development and Validation of American Indian Cultural Identity Stimulus Set: Implications for Future Research and Addressing Mental Health Disparities

284. Development and Validation of American Indian Cultural Identity Stimulus Set: Implications for Future Research and Addressing Mental Health Disparities

Beauty and the sharp fangs of the beast: degree of angularity predicts perceived preference and threat.

The evaluation of angular vs. curved forms has a long history in psychology but few of the many studies conducted have examined actual degree of angularity. In two experiments, we present observers with randomly positioned and randomly oriented texture displays of angles viewed within a circular frame. The angle conditions varied from 0° to 180° in 20° increments, covering the entire spectrum of possibilities including acute, obtuse, right, and straight line angles. In Experiment 1, 25 undergraduates rated the perceived beauty of these displays. In Experiment 2, the same stimulus set and procedure were used with 27 participants instead judging perceived threat. Based on the findings in the literature, we predicted that sharper angles would be judged less beautiful and more threatening. The results were mostly confirmed. Acute angles are preferred less but there are also distinct preferences for right angles and straight lines, perhaps due to their greater familiarity in constructed environments. There was a consistent and anticipated finding for threat in the second study: the sharper an angle, the greater its perceived threat. Fear of sharp objects as assessed in a personality questionnaire was found to positively correlate with threat judgements. Future work should look more closely at degree of angularity in embedded object contours and at individual response differences.

Spatiotemporal consistency of neural responses to repeatedly presented video stimuli accounts for population preferences

Population preferences for video advertisements vary across short video clips. What underlies these differences? Repeatedly watching a video clip may produce a consistent spatiotemporal pattern of neural activity that is dependent on the individual and the stimulus. Moreover, such consistency may be associated with the degree of engagement and memory of individual viewers. Since the population preferences are associated with the engagement and memory of the individual viewers, the consistency observed in a smaller group of viewers can be a predictor of population preferences. To test the hypothesis, we measured the degree of inter-trial consistency in participants’ electroencephalographic (EEG) responses to repeatedly presented television commercials. We observed consistency in the neural activity patterns across repetitive views and found that the similarity in the spatiotemporal patterns of neural responses while viewing popular television commercials predicts population preferences obtained from a large audience. Moreover, a regression model that used two datasets, including two separate groups of participants viewing different stimulus sets, showed good predictive performance in a leave-one-out cross-validation. These findings suggest that universal spatiotemporal patterns in EEG responses can account for population-level human behaviours.

Egocentric anchoring-and-adjustment underlies social inferences about known others varying in similarity and familiarity.

How do people infer the content of another person's mind? One documented strategy-at least when inferring the minds of strangers-entails anchoring on the content of one's own mind and serially adjusting away from this egocentric anchor. Yet, many social inferences concern known others in existing social relationships. In eight experiments with four sets of stimuli, we tested whether an egocentric anchoring-and-adjustment mechanism underlies social inferences about known targets, and whether it varies based on the target's similarity and familiarity to oneself. In Experiments 1-7, participants (Ntotal = 4,790) rated themselves and a known target on various characteristics (e.g., preferences, habits, traits), and response times for the target ratings were recorded. An integrative data analysis revealed that, consistent with egocentric anchoring-and-adjustment, the more discrepant the target ratings were from participants' self ratings, the longer participants took to provide target ratings. Importantly, this pattern of anchoring-and-adjustment was stronger for similar (vs. dissimilar) and familiar (vs. unfamiliar) targets, but it emerged in all experimental conditions. Experiment 8 (N = 549) suggested that these results were unlikely to be explained solely by a memory search process. We discuss implications for anchoring-and-adjustment as a mechanism underlying social inferences. (PsycInfo Database Record (c) 2022 APA, all rights reserved).

Does a lack of perceptual expertise prevent participants from forming reliable first impressions of "other-race" faces?

Many studies investigating first impressions from faces employ stimulus sets that comprise only White faces. It is argued that participants lack the necessary perceptual expertise to provide reliable trait evaluations when viewing faces from ethnicities that differ from their own. In combination with a reliance on White and WEIRD participants, this concern has contributed to the widespread use of White face stimuli in this literature. The present study sought to determine whether concerns about the use of so-called other-race faces are justified by assessing the test-retest reliability of trait judgments made about same- and other-race faces. In two experiments conducted on 400 British participants, we find that White British participants made reliable trait judgments about Black faces, and Black British participants made reliable trait judgments about White faces. It is important that future work be conducted to determine how widely these results generalize. Considering our findings, however, we suggest (a) that the default assumption in future first impressions research should be that participants-particularly those recruited from diverse communities-are able to form reliable first impressions of other-race faces and (b) that faces of color be included in stimulus sets whenever possible. (PsycInfo Database Record (c) 2022 APA, all rights reserved).

Analyzing facial expression decision times: Reaction time distribution matters.

People can decide whether a person appears either angry or happy in less than 1 second. Despite such speed, research shows that expression decisions are influenced by other facial attributes such as face sex. Nonetheless, specific patterns including participant sex differences remain unclear. Here, multiverse and distributional analyses clarify inconsistent results-participant sex differences for reaction time (RT) analyses were dependent on either an outlier removal method that effectively reduced the skew of the distribution or a specific distribution chosen to model the data. A further finding was that the patten of the Face Sex × Expression interaction effect for female participants differed markedly across the stimulus sets. The Diffusion Model, ex-Gaussian, ex-Wald, shifted Wald, and related distributions are recommended as replacements for analyses of mean RTs, rather than supplementary techniques. An extended analyses using the ex-Gaussian model is provided as an example. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

Correction to Tsantani et al. (2022).

Reports an error in "Does a lack of perceptual expertise prevent participants from forming reliable first impressions of "other-race" faces" by Maria Tsantani, Harriet Over and Richard Cook (Journal of Experimental Psychology: General, Advanced Online Publication, Nov 07, 2022, np). The original article is being made available open access under the CC-BY license following the University of Nottingham opt-in to the Jisc/APA Read and Publish agreement. The correct copyright is "© 2022 The Author(s)" and the CC-BY license disclaimer is below. All versions of this article have been corrected. "Open Access funding provided by Birkbeck, University of London: This work is licensed under a Creative Commons Attribution 4.0 International License (CC-BY). This license permits copying and redistributing the work in any medium or format, as well as adapting the material for any purpose, even commercially." (The following abstract of the original article appeared in record 2023-15561-001). Many studies investigating first impressions from faces employ stimulus sets that comprise only White faces. It is argued that participants lack the necessary perceptual expertise to provide reliable trait evaluations when viewing faces from ethnicities that differ from their own. In combination with a reliance on White and WEIRD participants, this concern has contributed to the widespread use of White face stimuli in this literature. The present study sought to determine whether concerns about the use of so-called other-race faces are justified by assessing the test-retest reliability of trait judgments made about same- and other-race faces. In two experiments conducted on 400 British participants, we find that White British participants made reliable trait judgments about Black faces, and Black British participants made reliable trait judgments about White faces. It is important that future work be conducted to determine how widely these results generalize. Considering our findings, however, we suggest (a) that the default assumption in future first impressions research should be that participants-particularly those recruited from diverse communities-are able to form reliable first impressions of other-race faces and (b) that faces of color be included in stimulus sets whenever possible. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

Evaluative context and conditioning effects among same and different objects.

We address an apparent discrepancy in the literature on how context stimuli influence evaluations of target stimuli. While a rich literature suggests that target evaluations are often contrasted away from the valence of context stimuli, reported effects of evaluative conditioning (EC) are almost exclusively assimilative. Specifically, when a neutral conditioned stimulus (CS) repeatedly co-occurs with a positive unconditioned stimulus (US), the CS is later evaluated more positively. Contrast effects from mere co-occurrences are absent in the EC literature. We hypothesized that this can be explained by the stimulus composition in EC tasks, which usually depict different objects as target (CS) and context (US). In 10 experiments, we confirmed that when target and context stimuli depict different objects, assimilation clearly dominates. Yet, when target and context depict stimuli from the same object class, contrast effects become dominant. These contrast effects are invisible in standard EC tasks because CSs are contrasted with all positive and negative USs of a given stimulus set. The present work thereby identifies a central determinant of the direction that evaluative context and conditioning effects take. While different-object contexts evoke assimilation, same-object contexts increase the likelihood of contrastive evaluations. We discuss the various theoretical and practical implications of our findings. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

Dissociating the Impact of Memorability on Electrophysiological Correlates of Memory Encoding Success.

Despite its unlimited capacity, not all visual information we encounter is encoded into visual long-term memory. Traditionally, variability in encoding success has been ascribed to variability in the types and efficacy of an individual's cognitive processes during encoding. Accordingly, past studies have identified several neural correlates of variability in encoding success, namely, frontal positivity, occipital alpha amplitude, and frontal theta amplitude, by contrasting the electrophysiological signals recorded during successful and failed encoding processes (i.e., subsequent memory). However, recent research demonstrated individuals remember and forget consistent sets of stimuli, thereby elucidating stimulus-intrinsic factors (i.e., memorability) that determine the ease of memory encoding independent of individual-specific variability in encoding processes. The existence of memorability raises the possibility that canonical EEG correlates of subsequent memory may reflect variability in stimulus-intrinsic factors rather than individual-specific encoding processes. To test this, we recorded the EEG correlates of subsequent memory while participants encoded 600 images of real-world objects and assessed the unique contribution of individual-specific and stimulus-intrinsic factors on each EEG correlate. Here, we found that frontal theta amplitude and occipital alpha amplitude were only influenced by individual-specific encoding success, whereas frontal positivity was influenced by stimulus-intrinsic and individual-specific encoding success. Overall, our results offer novel interpretations of canonical EEG correlates of subsequent memory by demonstrating a dissociable impact of stimulus-intrinsic and individual-specific factors of memory encoding success.

Below zero? Universal distance effect and situated space and size associations in negative numbers

While some researchers place negative numbers on a so-called extended mental number line to the left of positive numbers, others claim that negative numbers do not have mental representations but are processed through positive numbers combined with transformation rules. We measured spatial associations of negative numbers with a modified implicit association task that avoids spatial confounds present in most previous studies. In two lab-based magnitude classification experiments (each including 24 participants) and two online replications (with 74 and 77 participants, respectively), positive and negative numbers were combined with two spatial contexts: either directional symbols (left- or right-pointing arrows) or rectangles of varying sizes. In all experiments, we found a robust distance effect for negative numbers. However, there were no consistent associations of negative numbers with directional or size contexts. In the context of directional symbols, holistic processing was prevalent only in the small negative number range (-9, -8, -7, -6) when ensured by the stimulus set, supporting an extended mental number line. In the context of rectangles, however, large negative numbers from -4 to -1 were perceived as small, thus supporting rule-based processing. For negative number processing in the context of size, we further suggest the Semantic-Perceptual Size Congruity Cuing model (SPeSiCC model). We show that associations of size with negative numbers underly more complex processing mechanisms than mere recruitment of a transformation rule. In general, we conclude that associations of negative numbers with space and size are situated in the context, as they depend on the presented number range and differ for spatial direction and size.

Emotionally Loaded Visual Stimuli to Alter Brain Arousal: A Flicker Fusion Study

Background: Human brain performance and arousal are still challenging and critical, especially in environments such as power plants. Since different emotions are common in daily work life and have inevitable effects on cognitive performance, it is important to evaluate whether emotional interventions can alter brain arousal. Poor cognitive performance in control room operators (CROs) can lead to mental fatigue and affect their cognitive emotion regulation. To address this issue, flicker fusion frequency (FFF) was employed as a simple and reproducible surrogate index for mental fatigue. Objectives: This study aimed to investigate whether emotionally loaded visual stimuli can alter brain arousal (brain fatigue) or is associated with cognitive emotion regulation (CER) ability. Methods: Flicker fusion frequency was assessed by RT-961, and the International Affective Picture System (IAPS) was adopted as the picture database of stimuli. Additionally, the Cognitive Emotion Regulation Questionnaire (CERQ) was used to determine the participants’ cognitive emotion CER ability. Twenty volunteer CROs from Fars Combined Cycle Power Plant participated in this study. After completing the CERQ, they were assessed at 2 different time points (ie, before and after presenting emotional stimuli). Flicker fusion frequency was assessed 20 times at each round, and the average frequency was recorded. Emotionally loaded images were considered as stimuli. The stimuli sets were classified based on their arousal levels and valences, yet they were presented in random order. Subjects were exposed to each image for 5 seconds (30 minutes in total). Results: The participants’ mean age was 39.55 ± 7.02 years. The first and second FFFs were 42.15 ± 3.90 and 41.96 ± 3.98 in the appropriate group and 42.82 ± 3.59 and 42.26 ± 4.07 in the inappropriate group. Based on the statistical tests, there were no significant relationships between the measurements (P &gt; 0.05). Conclusions: Control room operators may positively maintain their brain arousal during specific emotional stimuli when the intervention lasts less than 30 minutes. Considering the prolonged working hours in such industries (roughly over 8 hours a day) and the importance of cognitive aptitude in preventing work-related errors, we propose this line of research to gain momentum.

A data-driven investigation of human action representations

Understanding actions performed by others requires us to integrate different types of information about people, scenes, objects, and their interactions. What organizing dimensions does the mind use to make sense of this complex action space? To address this question, we collected intuitive similarity judgments across two large-scale sets of naturalistic videos depicting everyday actions. We used cross-validated sparse non-negative matrix factorization to identify the structure underlying action similarity judgments. A low-dimensional representation, consisting of nine to ten dimensions, was sufficient to accurately reconstruct human similarity judgments. The dimensions were robust to stimulus set perturbations and reproducible in a separate odd-one-out experiment. Human labels mapped these dimensions onto semantic axes relating to food, work, and home life; social axes relating to people and emotions; and one visual axis related to scene setting. While highly interpretable, these dimensions did not share a clear one-to-one correspondence with prior hypotheses of action-relevant dimensions. Together, our results reveal a low-dimensional set of robust and interpretable dimensions that organize intuitive action similarity judgments and highlight the importance of data-driven investigations of behavioral representations.

The Establishment of Incidental Bidirectional Naming through Multiple Exemplar Instruction: a Systematic Replication.

Although many neurotypical children acquire untaught word-object relations incidentally from naturally occurring environmental experiences, many children with and without developmental disabilities require specific intervention. This study examined the effects of rotating listener (match and point) and speaker (tact and intraverbal-tact) responses with added echoics during multiple exemplar instruction (MEI) with training sets of stimuli on the acquisition of Incidental Bidirectional Naming (Inc-BiN). Listener-speaker MEI procedures reported in Hawkins et al.European Journal of Behavior Analysis, 10(2), 265-273, (2009) were replicated with procedural modification, new instructors, and new participants (four preschoolers with and without disabilities). The listener-speaker MEI with added echoics consisted of rotating across four response operants: match-with-echoics, point-with-echoics, tact, and intraverbal-tact responses. We measured the establishment of Inc-BiN through the number of the correct untaught listener (point) and untaught speaker (intraverbal-tact) responses for untaught stimuli during the listener-speaker MEI with added echoics. We found that listener-speaker MEI with added echoics was effective in establishing Inc-BiN for 3 of 4 participants.

Effects of a dynamically changing response set overlap on n − 2 repetition costs

N − 2 repetition costs are a marker for inhibition processes during task switching that are supposed to reduce interference from currently irrelevant information. The present study aimed at elucidating effects of response set overlap on n − 2 repetition costs while keeping stimulus set overlap constant. For this purpose, each task was associated with two different response sets. The relevant response set was visually cued in every trial. N − 2 repetition costs were present when the response set overlapped from trial n − 2 to trial n − 1. In contrast, they were abolished when the response set switched. This result is interpreted in terms of stronger interference for overlapping response sets that need to be inhibited to a high degree, resulting in large n − 2 repetition costs. Furthermore, the present results support the notion that two means for interference reduction, task inhibition and task shielding, are deployed in a flexible way depending on environmental demands.