Contextual Stimuli Research Articles

Decoding contextual influences on auditory perception from primary auditory cortex

Perception can be highly dependent on stimulus context, but whether and how sensory areas encode the context remains uncertain. We used an ambiguous auditory stimulus – a tritone pair – to investigate the neural activity associated with a preceding contextual stimulus that strongly influenced the tritone pair’s perception: either as an ascending or a descending step in pitch. We recorded single-unit responses from a population of auditory cortical cells in awake ferrets listening to the tritone pairs preceded by the contextual stimulus. We find that the responses adapt locally to the contextual stimulus, consistent with human MEG recordings from the auditory cortex under the same conditions. Decoding the population responses demonstrates that cells responding to pitch-changes are able to predict well the context-sensitive percept of the tritone pairs. Conversely, decoding the individual pitch representations and taking their distance in the circular Shepard tone space predicts the opposite of the percept. The various percepts can be readily captured and explained by a neural model of cortical activity based on populations of adapting, pitch and pitch-direction cells, aligned with the neurophysiological responses. Together, these decoding and model results suggest that contextual influences on perception may well be already encoded at the level of the primary sensory cortices, reflecting basic neural response properties commonly found in these areas.

Decoding contextual influences on auditory perception from primary auditory cortex.

Perception can be highly dependent on stimulus context, but whether and how sensory areas encode the context remains uncertain. We used an ambiguous auditory stimulus - a tritone pair - to investigate the neural activity associated with a preceding contextual stimulus that strongly influenced the tritone pair's perception: either as an ascending or a descending step in pitch. We recorded single-unit responses from a population of auditory cortical cells in awake ferrets listening to the tritone pairs preceded by the contextual stimulus. We find that the responses adapt locally to the contextual stimulus, consistent with human MEG recordings from the auditory cortex under the same conditions. Decoding the population responses demonstrates that cells responding to pitch-changes are able to predict well the context-sensitive percept of the tritone pairs. Conversely, decoding the individual pitch representations and taking their distance in the circular Shepard tone space predicts the opposite of the percept. The various percepts can be readily captured and explained by a neural model of cortical activity based on populations of adapting, pitch and pitch-direction cells, aligned with the neurophysiological responses. Together, these decoding and model results suggest that contextual influences on perception may well be already encoded at the level of the primary sensory cortices, reflecting basic neural response properties commonly found in these areas.

Empirical Testing of a Middle-Range Theory for Ineffective Breathing Pattern in Children With Congenital Heart Disease.

To test a middle-range theory (MRT) for the nursing diagnosis of ineffective breathing pattern in children with congenital heart disease (CHD) based on analysis of two general propositions. This cross-sectional study is guided by STROBE. The propositions represent hypotheses about the relationships between the concepts of this MRT to be tested empirically, and thus, log-linear models were used to verify the structure of the proposition related to the stimuli. Diagnostic accuracy measures, univariate logistic regressions and the Mann-Whitney test were used to analyse the structure of the propositions related to behaviours. The analysis of the propositions related to the stimuli (eight concepts, four of which were classified as focal stimuli and four as contextual stimuli) suggested a reclassification of the stimulus "deformities in the thoracic wall" which became too focal. In the analysis of the propositions related to behaviours (17 concepts, five of which were classified as acute confirmatory, nine as acute clinical deterioration and three classified as chronic), guided changes in the operationalisation of concepts were suggested after comparing clinical findings; thus, acute confirmatory behaviours now have 10 concepts, while acute clinical deterioration behaviours and chronic behaviours continued with nine and three concepts, respectively, but with reclassifications between them. Changes in the operationalisation of the classification of the elements of the two propositions occurred after comparing the clinical findings with the theoretical model. By establishing precise causal relationships and describing how IBP manifests itself over time in children with CHD, empirical testing of this MRT helps nurses understand clinical reasoning based on temporal logic and spectral interaction between diagnostic components, which in turn will improve the use and accuracy of nursing diagnoses. Children and adolescents with CHD were recruited for this study sharing their clinical history and physical lung examination.

A Systematic Review on Sex Differences in Prepulse Inhibition of Startle

Abstract: Prepulse inhibition of the startle response is defined as the inhibition of the startle reflex to an intense contextual stimulus (named pulse) when a weaker stimulus (named prepulse) precedes it and is considered a measure of sensorimotor gating. Consistent with recent research, it has been observed that this measure might exhibit sex differences in studies of both humans and rodents, although the results in the literature appear to be inconsistent. Therefore, this systematic review aims to analyze the sexual differences observed in human and nonhuman animal studies from a comparative perspective. A comprehensive search was conducted from the inception to the present in the Web of Science, PubMed, and PsycInfo databases. Following the search, 58 studies were included in the review. The average age in human studies ( n = 32) was 31.45 years (range = 4–69), while among nonhuman animal studies ( n = 26), the average age was 75.5 postnatal days (range = 7–360). The results indicated no clear sexual differences in the startle response magnitude. However, consistent sex differences in prepulse inhibition were found, revealing that males exhibited higher levels of sensorimotor gating compared to females in both humans (78.79% of the studies) and nonhuman animal studies (69.23% of the studies). Therefore, the findings corroborate the sex differences of prepulse inhibition and underscore the value of this paradigm in comparative science, emphasizing the importance of considering sex as an independent variable when studying this phenomenon.

Understanding responses of people with ASD in diverse reasoning tasks: A formal study.

Recent studies have shown that in some reasoning tasks people with Autism Spectrum Disorder perform better than typically developing people. This paper compares four such tasks, namely a syllogistic task, two decision-making tasks, and a task from the heuristics and biases literature, the aim being to identify common structure as well as differences. In the terminology of David Marr's three levels of cognitive systems, the tasks show commonalities on the computational level in terms of the effect of contextual stimuli, though an in-depth analysis of such contexts provides certain distinguishing features in the algorithmic level. We also make some general remarks on our approach, so as to set the stage for further studies in the area which could provide a better understanding of the reasoning process of ASD individuals.

Spatial context non-uniformly modulates inter-laminar information flow in the primary visual cortex.

Our visual experience is a result of the concerted activity of neuronal ensembles in the sensory hierarchy. Yet, how the spatial organization of objects influences this activity remains poorly understood. We investigate how inter-laminar information flow within the primary visual cortex (V1) is affected by visual stimuli in isolation or with flankers at spatial configurations that are known to cause non-uniform degradation of perception. By employing dimensionality reduction approaches to simultaneous, layer-specific population recordings, we establish that information propagation between cortical layers occurs along a structurally stable communication subspace. The spatial configuration of contextual stimuli differentially modulates inter-laminar communication efficacy, the balance of feedforward and effective feedback signaling, and contextual signaling in the superficial layers. Remarkably, these modulations mirror the spatially non-uniform aspects of perceptual degradation. Our results suggest a model of retinotopically non-uniform cortical connectivity in the output layers of V1 that influences information flow in the sensory hierarchy.

Contextuality of cognitive control deficits in alcohol dependence — pro et contra

Cognitive impairment, including cognitive control, mediates the negative social consequences of alcohol-related behavior, but few studies have examined these processes in the Russian speaking population using modern and standardized assessment methods. Thus, the aim of the study was to examine the features of cognitive control (inhibition of automatic response) and the general level of cognitive functioning in a Russianspeaking sample of alcohol-dependent individuals (AD) using quantitative assessment methods. Materials and Methods. 111 individuals diagnosed with alcohol dependence (F10.30) and 27 healthy participants were examined by using the Brief Assessment of Cognitive Functioning in Affective Disorders Battery (BAC-A) and additional tests of cognitive control (Stroop test with incongruent stimuli, Stroop test with alcohol-associated stimuli). The statistical methods were U-Mann-Whitney test, Spearman correlation coefficient, two-stage least squares regression. Results. In the AD group the indices of cognitive functioning were significantly lower in all parameters except for the subtests of verbal memory and digit sequence (p<0,05). The model of the relationship between the parameters of general cognitive functioning and cognitive control reveals that the index of incongruence to alcohol-related stimuli was a significant predictor of sampe affiliation. Discussion. The obtained results may indicate the presence of impairments of speed of mental processes, planning , verbal fluency and response inhibition function in the group of individuals with AD. In the studied group, the automatic response inhibition function mediates the general cognitive functioning only within the relevant contextual stimuli.

Why might animals remember? A functional framework for episodic memory research in comparative psychology.

One of Clayton's major contributions to our understanding of animal minds has been her work on episodic-like memory. A central reason for the success of this work was its focus on ecological validity: rather than looking for episodic memory for arbitrary stimuli in artificial contexts, focussing on contexts in which episodic memory would serve a biological function such as food caching. This review aims to deepen this insight by surveying the numerous functions that have been proposed for episodic memory, articulating a philosophically grounded framework for understanding what exactly functions are, and drawing on these to make suggestions for future directions in the comparative cognitive psychology of episodic memory. Our review suggests four key insights. First, episodic memory may have more than one function and may have different functions in different species. Second, cross-disciplinary work is key to developing a functional account of episodic memory. Third, there is scope for further theoretical elaboration of proposals relating episodic memory to food caching and, in particular, future-oriented cognition. Finally, learning-related functions suggested by AI (artificial intelligence)-based models are a fruitful avenue for future behavioural research.

The tilt illusion arises from an efficient reallocation of neural coding resources at the contextual boundary.

The tilt illusion - a bias in the perceived orientation of a center stimulus induced by an oriented surround - illustrates how context shapes visual perception. While the tilt illusion has been the subject of quantitative study for over 85 years, we still lack a comprehensive account of the phenomenon that connects its neural and behavioral characteristics. Here, we demonstrate that the tilt illusion originates from a dynamic change in neural coding precision induced by the surround context. We simultaneously obtained psychophysical and fMRI responses from human subjects while they viewed gratings in the absence and presence of an oriented surround, and extracted sensory encoding precision from their behavioral and neural data. Both measures show that in the absence of a surround, encoding reflects the natural scene statistics of orientation. However, in the presence of an oriented surround, encoding precision is significantly increased for stimuli similar to the surround orientation. This local change in encoding is sufficient to accurately predict the behavioral characteristics of the tilt illusion using a Bayesian observer model. The effect of surround modulation increases along the ventral stream, and is localized to the portion of the visual cortex with receptive fields at the center-surround boundary. The pattern of change in coding accuracy reflects the surround-conditioned orientation statistics in natural scenes, but cannot be explained by local stimulus configuration. Our results suggest that the tilt illusion naturally emerges from a dynamic coding strategy that efficiently reallocates neural coding resources based on the current stimulus context.

How emotions catalyse learning through study tours: Evidence from Panda Ambassador

Emotions are critical antecedents to learning in the academic education context. However, how emotions flow, and how emotions affect learning in study tours remains unclear. This case study focused on a UNESCO study tour program, the Panda ambassador 2023, to address the gap. A mixed-method approach was applied, collecting data through daily questionnaires, written diaries, and interviews. A wide spectrum of emotions was identified throughout the study tour. Both emotional valence and intensity affect learning outcomes. Motivations, embodiment, peer interactions, tutorial instructions, itineraries, and contextual stimuli affect how emotions stimulate learning outcomes. Theoretically, our work presents a framework explicating how emotions affect tourist learning. Practically, implications are made for destination managers and study tour practitioners on experience and product design.

Mapping functional traces of opioid memories in the rat brain.

Addiction to psychoactive substances is a maladaptive learned behaviour. Contexts surrounding drug use integrate this aberrant mnemonic process and hold strong relapse-triggering ability. Here, we asked where context and salience might be concurrently represented in the brain during retrieval of drug-context paired associations. For this, we developed a morphine-conditioned place preference protocol that allows contextual stimuli presentation inside a magnetic resonance imaging scanner and investigated differences in activity and connectivity at context recall. We found context-specific responses to stimulus onset in multiple brain regions, namely, limbic, sensory and striatal. Differences in functional interconnectivity were found among amygdala, lateral habenula, and lateral septum. We also investigated alterations to resting-state functional connectivity and found increased centrality of the lateral septum in a proposed limbic network, as well as increased functional connectivity of the lateral habenula and hippocampal 'cornu ammonis' 1 region, after a protocol of associative drug-context. Finally, we found that pre- conditioned place preference resting-state connectivity of the lateral habenula and amygdala was predictive of inter-individual conditioned place preference score differences. Overall, our findings show that drug and saline-paired contexts establish distinct memory traces in overlapping functional brain microcircuits and that intrinsic connectivity of the habenula, septum, and amygdala likely underlies the individual maladaptive contextual learning to opioid exposure. We have identified functional maps of acquisition and retrieval of drug-related memory that may support the relapse-triggering ability of opioid-associated sensory and contextual cues. These findings may clarify the inter-individual sensitivity and vulnerability seen in addiction to opioids found in humans.

How to reward animals based on their subjective percepts: A Bayesian approach to online estimation of perceptual biases.

Elucidating the neural basis of perceptual biases, such as those produced by visual illusions, can provide powerful insights into the neural mechanisms of perceptual inference. However, studying the subjective percepts of animals poses a fundamental challenge: unlike human participants, animals cannot be verbally instructed to report what they see, hear, or feel. Instead, they must be trained to perform a task for reward, and researchers must infer from their responses what the animal perceived. However, animals' responses are shaped by reward feedback, thus raising the major concern that the reward regimen may alter the animal's decision strategy or even intrinsic perceptual biases. We developed a method that estimates perceptual bias during task performance and then computes the reward for each trial based on the evolving estimate of the animal's perceptual bias. Our approach makes use of multiple stimulus contexts to dissociate perceptual biases from decision-related biases. Starting with an informative prior, our Bayesian method updates a posterior over the perceptual bias after each trial. The prior can be specified based on data from past sessions, thus reducing the variability of the online estimates and allowing it to converge to a stable estimate over a small number of trials. After validating our method on synthetic data, we apply it to estimate perceptual biases of monkeys in a motion direction discrimination task in which varying background optic flow induces robust perceptual biases. This method overcomes an important challenge to understanding the neural basis of subjective percepts.

Decoding contextual influences on auditory perception from primary auditory cortex.

Perception can be highly dependent on stimulus context, but whether and how sensory areas encode the context remains uncertain. We used an ambiguous auditory stimulus - a tritone pair - to investigate the neural activity associated with a preceding contextual stimulus that strongly influenced the tritone pair's perception: either as an ascending or a descending step in pitch. We recorded single-unit responses from a population of auditory cortical cells in awake ferrets listening to the tritone pairs preceded by the contextual stimulus. We find that the responses adapt locally to the contextual stimulus, consistent with human MEG recordings from the auditory cortex under the same conditions. Decoding the population responses demonstrates that cells responding to pitch-class-changes are able to predict well the context-sensitive percept of the tritone pairs. Conversely, decoding the individual pitch-class representations and taking their distance in the circular Shepard tone space predicts the opposite of the percept. The various percepts can be readily captured and explained by a neural model of cortical activity based on populations of adapting, pitch-class and pitch-class-direction cells, aligned with the neurophysiological responses. Together, these decoding and model results suggest that contextual influences on perception may well be already encoded at the level of the primary sensory cortices, reflecting basic neural response properties commonly found in these areas.

Self-Regulation in Eating Behaviors: The Role of Executive Function in Response to Food Stimuli.

Human nutrition is characterized by both automatic and self-regulated processes. One of the dimensions that may be employed in monitoring eating behaviors is the cognitive control played by the executive functions (EFs). The role of EFs in affecting eating behaviors has been assessed in empirical studies, but further analyses are needed in a current society characterized by a food-abundant environment. Accordingly, this study attempted to evaluate the association between weight status and executive functions in response to food-related stimuli. One hundred and forty-four young adults took part in the study (25.7% in overweight condition). The participants completed a set of computerized cognitive tasks to assess cognitive and motor inhibition and working memory in two different conditions: (i) classic versions of the tasks and (ii) modified versions with food cues. The results indicate that food stimuli may influence executive performance and that there is an association between food cue-related executive functioning, particularly in the domain of motor inhibition, and working memory. These results suggest that self-regulation in nutrition may involve executive control. Although further studies are needed, this work suggests the importance of a multidimensional perspective in the analysis of eating behaviors and the relevance of EFs in monitoring our approach to food stimuli in an environmental context.

Behavioral Activation and Brain Network Changes in Depression.

Behavioral activation (BA) is a well-established method of evidence-based treatment for depression. There are clear links between the neural mechanisms underlying reward processing and BA treatment for depressive symptoms, including anhedonia; however, integrated interpretations of these two domains are lacking. Here we examine brain imaging studies involving BA treatments to investigate how changes in brain networks, including the reward networks, mediate the therapeutic effects of BA, and whether brain circuits are predictors of BA treatment responses. Increased activation of the prefrontal and subcortical regions associated with reward processing has been reported after BA treatment. Activation of these regions improves anhedonia. Conversely, some studies have found decreased activation of prefrontal regions after BA treatment in response to cognitive control stimuli in sad contexts, which indicates that the therapeutic mechanism of BA may involve disengagement from negative or sad contexts. Furthermore, the decrease in resting-state functional connectivity of the default-mode network after BA treatment appears to facilitate the ability to counteract depressive rumination, thereby promoting enjoyable and valuable activities. Conflicting results suggest that an intact neural response to rewards or defective reward functioning is predictive of the efficacy of BA treatments. Increasing the benefits of BA treatments requires identification of the unique individual characteristics determining which of these conflicting findings are relevant for the personalized treatment of each individual with depression.

One-Trial Appetitive Learning Tasks for Drug Targeting.

One-trial appetitive learning developed from one-trial passive avoidance learning as a standard test of retrograde amnesia. It consists of one learning trial followed by a retention test, in which physiological manipulations are presented. As in passive avoidance learning, food- or waterdeprived rats or mice finding food or water inside an enclosure are vulnerable to the retrograde amnesia produced by electroconvulsive shock treatment or the injection of various drugs. In one-trial taste or odor learning conducted in rats, birds, snails, bees, and fruit flies, there is an association between a food item or odorant and contextual stimuli or the unconditioned stimulus of Pavlovian conditioning. The odor-related task in bees was sensitive to protein synthesis inhibition as well as cholinergic receptor blockade, both analogous to results found on the passive avoidance response in rodents, while the task in fruit flies was sensitive to genetic modifications and aging, as seen in the passive avoidance response of genetically modified and aged rodents. These results provide converging evidence of interspecies similarities underlying the neurochemical basis of learning.

Evidence for proactive and retroactive temporal pattern analysis in simultaneous maskinga).

Amplitude modulation (AM) of a masker reduces its masking on a simultaneously presented unmodulated pure-tone target, which likely involves dip listening. This study tested the idea that dip-listening efficiency may depend on stimulus context, i.e., the match in AM peakedness (AMP) between the masker and a precursor or postcursor stimulus, assuming a form of temporal pattern analysis process. Masked thresholds were measured in normal-hearing listeners using Schroeder-phase harmonic complexes as maskers and precursors or postcursors. Experiment 1 showed threshold elevation (i.e., interference) when a flat cursor preceded or followed a peaked masker, suggesting proactive and retroactive temporal pattern analysis. Threshold decline (facilitation) was observed when the masker AMP was matched to the precursor, irrespective of stimulus AMP, suggesting only proactive processing. Subsequent experiments showed that both interference and facilitation (1) remained robust when a temporal gap was inserted between masker and cursor, (2) disappeared when an F0-difference was introduced between masker and precursor, and (3) decreased when the presentation level was reduced. These results suggest an important role of envelope regularity in dip listening, especially when masker and cursor are F0-matched and, therefore, form one perceptual stream. The reported effects seem to represent a time-domain variant of comodulation masking release.

Use of the overexpectation effect to reduce conditioned seeking behavior controlled by nicotine.

Nicotine produces robust stimulus effects that can be conditioned to form associations with reinforcing nondrug stimuli. We examine how established associations to the nicotine stimulus may be weakened via the overexpectation effect. In two experiments, we separately conditioned sucrose associations to the interoceptive nicotine stimulus (0.4 mg/kg, SC) and to a "noisy" exteroceptive contextual stimulus (oscillating houselight and white noise) via the discriminated goal-tracking task. Thereafter, we presented additional sucrose pairings with the nicotine and noisy stimuli, now in compound. Testing of the conditioned goal-tracking evoked by the nicotine and noisy stimuli in isolation-before versus after compound conditioning (Experiment 1) or between treatment and control groups (Experiment 2)-demonstrated an attenuation of conditioned responding via the overexpectation effect. We suggest that applications of the overexpectation effect may provide some promise for treatments seeking to attenuate drug-evoked conditioned responses in situations where extinction-based interventions are not suitable.

Transfer of cognitive control adjustments within and between speakers.

Congruency effects in conflict tasks are typically larger after congruent compared to incongruent trials. This congruency sequence effect (CSE) indicates that top-down adjustments of cognitive control transfer between processing episodes, at least when controlling for bottom-up memory processes by alternating between stimulus-response (S-R) sets in confound-minimised designs. According to the control-retrieval account, cognitive control is bound to task-irrelevant context features (e.g., stimulus position or modality) and retrieved upon subsequent context feature repetitions. A confound-minimised CSE should therefore be larger when context features repeat rather than change between two trials. This study tested this prediction for a more abstract contextual stimulus feature, speaker gender. In two preregistered auditory prime-probe task experiments, participants classified colour words spoken by a female or male voice. Across both experiments, we found confound-minimised CSEs that were not reliably affected by whether the speaker gender repeated or changed. This indicates that speaker transitions have virtually no influence on the transfer of control adjustments in the absence of S-R repetitions. By contrast, when allowing for bottom-up memory processes by repeating the S-R set, CSEs were consistently larger when the speaker gender repeated compared to changed. This suggests that speaker transitions can in principle influence transfer between processing episodes. The discrepancy also held true when considering learning and test episodes separated by an intervening episode. Thus, the present findings call for a refinement of the control-retrieval account to accommodate the role of more abstract contextual stimulus features for the maintenance of memory traces in auditory conflict processing.

Attentional Differences Between Males and Females for Emojis During the Emotional Stroop Task.

Introduction Cognitive load can be intensified by emotional components such as emotive words or facial expressions. Sexdifferences influence both emotional and cognitive functions for emotional facial expressions. Emojis, in contrast to human faces, serve as digital cues conveying emotional nuances in communication. The present study aimed to compare attentional differences prompted by emojis. Methods This study aimed to compare attentional differences in males and females elicited by emojis in 100 healthy adults (50 males and 50 females) within the age group of 18 to 40 years (mean ± SD: 27.87 ± 5.37 years) while performing the emotional Stroop task (EST). The EST comprised emojis depicting four emotions (happy, fear, sad, and angry) and emotionally charged words conveying similar emotions. An independent sample t-test was used to compare the reaction times among males and females. Results Results showed males had significantly longer reaction times than females across all task conditions. Both genders exhibited significant differences in reaction times across task conditions, except inhibition. Overall, reaction times increased notably from neutral to incongruent conditions for both genders. This suggests that response times increased significantly from neutral to incongruent conditions. Conclusion Emojis introduced in the EST revealed gender-related differences in attentional processing. This study showed the greater proficiency of females in emotional processing during EST compared to males. These findings contribute to our understanding of how gender is associated with cognitive responses to emotional stimuli in digital communication contexts.