Variation In Perception Research Articles

Attitudes toward mandatory vaccination and the COVID certificate as a function of vaccination status and risk perception: A vignette‐based study

AbstractIn January 2022, several vaccination policies were debated to address the Omicron outbreak in Belgium. Considering variability in risk perception and vaccine uptake, this study aimed to understand differences in support and expectations for four scenarios, ranging from relaxed to restrictive vaccination policies, to inform policymakers. Using an online survey, 12,670 participants (46% female; Mage = 45.9, SD = 13.38) reported their risk perception, number of vaccination doses (0/1, 2, 3 doses) as well as their support and several anticipated psychological outcomes for each scenario. Mixed model ANCOVA showed a pattern of preferential support for the relaxed scenario and more positive anticipated outcomes (general well‐being and government appraisals) compared to the restrictive policies, that were treated equivalently. An exception to this pattern was found when people were vaccinated with three doses and perceived high risk. Taken separately, risk perception and vaccination status were not sufficient to drive positive attitudes toward restrictive policies; only their interaction had an effect. Limitations include the self‐selected sample and the vignette methodology. The conjunct role of risk perception and vaccination status should be considered when discussing the introduction of restrictive vaccination policies. These findings inform vaccination strategies management during pandemics.

Sonic emotion: variability of perception based on context and state

The study explored the momentary emotional disposition of 71 subjects (average age 23.2 years) by exposing them to six songs from different eras. Participants were asked to describe the emotions or feelings evoked by each song immediately after listening. This process was repeated after a 4-month interval, using the same songs in the same order to assess changes in emotional perception. Results indicated that in more than half of the cases, subjects provided different responses in the two stages of the study. This phenomenon suggests that emotional reactions to the respective songs were significantly influenced by the subjects' mood at the time of listening.

Interference of mid-level sound statistics underlie human speech recognition sensitivity in natural noise.

Recognizing speech in noise, such as in a busy restaurant, is an essential cognitive skill where the task difficulty varies across environments and noise levels. Although there is growing evidence that the auditory system relies on statistical representations for perceiving 1-5 and coding4,6-9 natural sounds, it's less clear how statistical cues and neural representations contribute to segregating speech in natural auditory scenes. We demonstrate that human listeners rely on mid-level statistics to segregate and recognize speech in environmental noise. Using natural backgrounds and variants with perturbed spectro-temporal statistics, we show that speech recognition accuracy at a fixed noise level varies extensively across natural backgrounds (0% to 100%). Furthermore, for each background the unique interference created by summary statistics can mask or unmask speech, thus hindering or improving speech recognition. To identify the neural coding strategy and statistical cues that influence accuracy, we developed generalized perceptual regression, a framework that links summary statistics from a neural model to word recognition accuracy. Whereas a peripheral cochlear model accounts for only 60% of perceptual variance, summary statistics from a mid-level auditory midbrain model accurately predicts single trial sensory judgments, accounting for more than 90% of the perceptual variance. Furthermore, perceptual weights from the regression framework identify which statistics and tuned neural filters are influential and how they impact recognition. Thus, perception of speech in natural backgrounds relies on a mid-level auditory representation involving interference of multiple summary statistics that impact recognition beneficially or detrimentally across natural background sounds.

Aperiodic EEG Predicts Variability of Visual Temporal Processing.

The human brain exhibits both oscillatory and aperiodic, or 1/f, activity. Although a large body of research has focused on the relationship between brain rhythms and sensory processes, aperiodic activity has often been overlooked as functionally irrelevant. Prompted by recent findings linking aperiodic activity to the balance between neural excitation and inhibition, we investigated its effects on the temporal resolution of perception. We recorded electroencephalography (EEG) from participants (both sexes) during the resting state and a task in which they detected the presence of two flashes separated by variable interstimulus intervals. Two-flash discrimination accuracy typically follows a sigmoid function whose steepness reflects perceptual variability or inconsistent integration/segregation of the stimuli. We found that individual differences in the steepness of the psychometric function correlated with EEG aperiodic exponents over posterior scalp sites. In other words, participants with flatter EEG spectra (i.e., greater neural excitation) exhibited increased sensory noise, resulting in shallower psychometric curves. Our finding suggests that aperiodic EEG is linked to sensory integration processes usually attributed to the rhythmic inhibition of neural oscillations. Overall, this correspondence between aperiodic neural excitation and behavioral measures of sensory noise provides a more comprehensive explanation of the relationship between brain activity and sensory integration and represents an important extension to theories of how the brain samples sensory input over time.

Relationalism’s psychosemantic ills

Abstract Relationalism about colour (as described in Cohen’s 2004 article on colour properties and his 2009 book The Red and the Real) is motivated by the thought that by identifying colours with relations between objects, subjects and viewing circumstances we can provide the best realist, general, ecumenical accommodation of perceptual variation data. This ‘best’-claim is supported by the charge that one of the view’s ecumenical rivals does uniquely badly in respect of fit with mainstream psychosemantics. This case for relationalism is complicated by Cohen’s later acknowledgement that relationalism has psychosemantic ills of its own. In this paper I argue that Cohen’s proposed remedying of those ills fails.

Variability in odor hedonic perception: A challenge for neurosensory and behavioral research.

Odor hedonic perception (pleasant/unpleasant character) is considered to be the first and one of the most important dimensions in olfaction and is known to be highly variable and dependent on several factors related to the stimulus, individual characteristics, and context. Although numerous experimental studies have been published on this topic, there is no comprehensive general review on the variability in odor hedonic perception. Therefore, the aim of this article was to describe and detail all the factors involved in the variability in odor hedonic perception. Stimulus properties-related variability includes the concentration/intensity and the physicochemical properties. Individual-related variability includes sex, age, and physiological state characteristics, while context-related variability involves factors associated with the stimulation context, such as stimulation pathway, exposure frequency, verbal influences, cross-modal associations, hedonic contrast, and cultural background. Subsequently, a section is devoted to the brain processing of odor hedonicity, although its role in odor hedonic variability is largely unknown. Finally, the article discusses the relationship between the hedonic qualities of odors and the resulting behavioral responses in both animals and humans. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

Irregularity of visual motion perception and negative symptoms in schizophrenia.

Schizophrenia (SZ) is a severe psychiatric disorder characterized by perceptual, emotional, and behavioral abnormalities, with cognitive impairment being a prominent feature of the disorder. Recent studies demonstrate irregularity in SZ with increased variability on the neural level. Is there also irregularity on the psychophysics level like in visual perception? Here, we introduce a methodology to analyze the irregularity in a trial-by-trial way to compare the SZ and healthy control (HC) subjects. In addition, we use an unsupervised clustering algorithm K-means + + to identify SZ subgroups in the sample, followed by validation of the subgroups based on intraindividual visual perception variability and clinical symptomatology. The K-means + + method divided SZ patients into two subgroups by measuring durations across trials in the motion discrimination task, i.e., high, and low irregularity of SZ patients (HSZ, LSZ). We found that HSZ and LSZ subgroups are associated with more negative and positive symptoms respectively. Applying a mediation model in the HSZ subgroup, the enhanced irregularity mediates the relationship between visual perception and negative symptoms. Together, we demonstrate increased irregularity in visual perception of a HSZ subgroup, including its association with negative symptoms. This may serve as a promising marker for identifying and distinguishing SZ subgroups.

A Closer Look at Students' School Climate Perception: A Case Study of Urban and Rural Ukraine during COVID-19

Aim. This study analyses the impact of adaptive quarantine during the COVID-19 pandemic on the perception of school’s social climate by students in more or less urbanised areas. Methods. The data was collected in 2016 (before the pandemic, n=1801) and in 2020 (during the pandemic, n=2038) among randomly selected 9th-grade classes (mean age=14) in a large city (Lviv), a small town (Drohobych), and rural areas (Drohobych raion). Generalised linear regression mixed modelling was applied to assess the impact of gender, location, year of the survey, and for the 2020 - for the quality of coping with the pandemic situation – and the interactive effect of these factors on the variability of school climate perception. Results. Before the pandemic, the acceptability of school climate was the highest in rural areas and the lowest in the city. During the pandemic, it decreased among students from rural areas and increased in towns. Students who perceived COVID-19 pandemic restrictions as more burdensome evaluated their school climate more positively than students who coped well with the pandemic. Conclusion. The impact of the tense pandemic situation on the attitude of adolescents to school was complex and probably reflected the inequality in the education system in urban and rural areas.

Diverse Face Images (DFI): Validated for racial representation and eye gaze.

Face processing is a central component of human communication and social engagement. The present investigation introduces a set of racially and ethnically inclusive faces created for researchers interested in perceptual and socio-cognitive processes linked to human faces. The Diverse Face Images (DFI) stimulus set includes high-quality still images of female faces that are racially and ethnically representative, include multiple images of direct and indirect gaze for each model and control for low-level perceptual variance between images. The DFI stimuli will support researchers interested in studying face processing throughout the lifespan as well as other questions that require a diversity of faces or gazes. This report includes a detailed description of stimuli development and norming data for each model. Adults completed a questionnaire rating each image in the DFI stimuli set on three major qualities relevant to face processing: (1) strength of race/ethnicity group associations, (2) strength of eye gaze orientation, and (3) strength of emotion expression. These validation data highlight the presence of rater variability within and between individual model images as well as within and between race and ethnicity groups.

From color naming to color perception: Cross‐linguistic differences of the chromatic information processing in monolingual and bilingual speakers

AbstractThere has been long running debate about the interaction of language and perception. In this context, bilingual people have often shown benefits, due to their double‐active linguistic system, in cognitive functions, like inhibition, attention, and memory, which are central for visual perception. Color naming and categorization are domains for studying cross‐linguistic effects, which arise from conceptual and perceptual variations across speakers of different languages. In this study, we compared the ‘blue’ lexicon of highly proficient French‐Italian bilinguals to monolingual speakers of the corresponding languages. Prior studies have shown that Italian has two basic color terms for the blue area of color space: one denotes light blue hues (azzurro) and the other dark blue hues (blu), whilst French, with only one basic term bleu, lacks this distinction. We used a Stroop test to probe differences in perception and categorization of blue in bi‐ and monolingual speakers. We found that Italian monolinguals name the ink color more accurately and more rapidly when the word blu is rendered in dark blue ink (corresponding to the word blu) than when it is printed in light blue ink (corresponding to azzurro), since the latter represents an incongruent condition for them. This ‘category effect’ does not exist for French monolingual speakers. Our bilinguals' results demonstrate that, despite the emergence of a specific in‐between perceptual behavior, bilinguals generally performed like Italian monolinguals. These outcomes confirm the hypothesis that their second language categories (Italian) dominate their native language (French), attesting that lexical distinctions influence perceptual faculties in general. However, the ratio of the interference effect (longer reaction times for incongruent stimuli compared to control stimuli) and the facilitation effect (shorter reaction times for congruent stimuli compared to control stimuli) is not the same for bilinguals and monolinguals. The highest magnitude in the facilitation effect was revealed for bilinguals, whereas the highest magnitude in the interference effect was revealed for Italian monolingual speakers. This phenomenon adds evidence to the existence of enhanced bilingual cognitive control abilities.

Factors influencing vowel adaptation in English loanwords in Korean

Abstract This study explores the extent to which perceptual and other factors (i.e., orthography and standardization) affect vowel adaptation in English loanwords in Korean. It also examines whether perceptual variability gives rise to adaptation variability, and it further addresses whether the degree of perceptual influence in vowel adaptation is different from that in consonant adaptation. Data on Korean listeners’ perceptual mapping patterns for English vowels were collected in an English-to-Korean vowel category mapping experiment and compared to the patterns in a loanword database. The results indicate that perceptual factors have a great impact on the adaptation of English vowels into Korean, in line with de Jong and Cho’s (de Jong, Kenneth & Mi-Hui Cho. 2012. Loanword phonology and perceptual mapping: Comparing two corpora of Korean contact with English. Language 88. 341–368) findings for the adaptation of English consonants into Korean. Consequently, factors such as orthography and standardization are viewed as deviations from these perceptual influences. The impact of perceptual adaptation is, however, rather limited because the correlation between perceptual mappings and loanword mappings is less robust for English vowel adaptation than for English consonant adaptation possibly due to the less categorical nature of vowels relative to consonants. Additionally, the results show that increased strength of modal perceptual mappings is related to less loanword variability in vowel adaptation.

The Context Matters: Women's Experiences of Their Partner's Odor in Intimate and Sexual Encounters.

Research shows that male body odor plays an important role in women's mate choice and that olfactory abilities are associated with women's sexual functioning. What remains unclear is what types of partner's odor actually shape women's experience during intimate activities. This study therefore explored women's experience associated with the partner's various odors and investigated how they affect women's intimate and sexual encounters. We performed semi-structured individual interviews with 20 single women and 20 women in a long-term relationship. Thematic analysis revealed four key natural odor types of the partner: body odor, sweat, genital odor, and semen odor. Further, we have identified three main types of fragrance odor (cologne, shower gel, and laundry agents) and investigated their perception in both intimate (hugging, kissing, cuddling, lying side by side) and sexual (intercourse, oral sex, ejaculation) contexts. Both partner's natural odor and fragrance affected women's emotional state (ranging from pleasant to unpleasant) and behavioral response (ranging from approach to avoidance of partner). Women's odor perception was frequently context-dependent, so that even mostly negatively perceived odors (e.g., semen, genital odor) were often accepted as part of sexual encounter. Finally, women's perception was negatively modified by partner's specific sweat (after workday, workout, or when the partner is ill) during intimate encounters. Our results highlight the complexity and interindividual variability of partner's odor perception.

The interacting effects of talker, contrast, and listener variability in cross-language speech perception.

Building on previous observations of variability in speech research, we examine variability in speech perception study materials associated with the specific talker and contrast under examination. English-speaking listeners completed a web-based auditory AXB task involving Hindi dental-retroflex stop contrasts produced by four talkers. Main effects of talker and contrast, as well as the interaction of the two, were observed. Further, there was a great deal of individual listener variation. These findings complicate our ability to characterize the difficulty that Hindi dental-retroflex contrasts pose for English speakers, and lead to critical questions concerning the generalizability of speech perception study findings.

Odor, air quality, and well-being: understanding the urban smellscape using crowd-sourced science

Abstract Odors are a topic of emerging environmental health interest given their potential links to air quality, health, well-being, and quality of life. However, odors have traditionally been challenging to study given variability in individual sensitivity and perception, atmospheric physico-chemical processes, and emissions of mixtures of odorous contaminants. Here, we explore the potential utility of crowd-sourced odor report data in improving understanding of spatiotemporal patterns of odor experiences and their impacts. We conduct quantitative and qualitative analyses of a 12-month data set from a web application collecting crowd-sourced odor reports, including spatiotemporal information, odor and self-reported impacts description (OSAC: odors, symptoms, actions in response, and suspected causes), and demographics, in Vancouver, Canada. Users report diverse OSAC with strong seasonality and spatial variability. Reported symptoms, ranging from neurological to emotion- and mood-related, highlight the complexity of odor-related health and well-being impacts. Odors can trigger maladaptive actions, where individuals are exposed to other environmental stressors (e.g. heat stress) or curtail healthy behaviors (e.g. exercising outside) to cope with odor impacts. Clustering analysis of OSAC suggests that odor exposures may be linked to health, well-being, and quality of life impacts through complex mechanisms, related not only to the odor experienced but also perceived causes. Spatiotemporal patterns in reports highlight the potential influence of persistent sources (e.g. waste management) and transient events (e.g. accidents). Exploratory multiple linear regression models suggest that monitoring of air quality and meteorology may be insufficient to capture odor issues. Overall, these results suggest that crowd-sourced science incorporating self-reported health and well-being effects and behavioral responses can enrich understanding of the impacts of odorous emissions at large spatiotemporal scales and complement traditional air pollution monitoring.

Consequences of eye movements for spatial selectivity

What determines spatial tuning in the visual system? Standard views rely on the assumption that spatial information is directly inherited from the relative position of photoreceptors and shaped by neuronal connectivity.1,2 However, human eyes are always in motion during fixation,3,4,5,6 so retinal neurons receive temporal modulations that depend on the interaction of the spatial structure of the stimulus with eye movements. It has long been hypothesized that these modulations might contribute to spatial encoding,7,8,9,10,11,12 a proposal supported by several recent observations.13,14,15,16 A fundamental, yet untested, consequence of this encoding strategy is that spatial tuning is not hard-wired in the visual system but critically depends on how the fixational motion of the eye shapes the temporal structure of the signals impinging onto the retina. Here we used high-resolution techniques for eye-tracking17 and gaze-contingent display control18 to quantitatively test this distinctive prediction. We examined how contrast sensitivity, a hallmark of spatial vision, is influenced by fixational motion, both during normal active fixation and when the spatiotemporal stimulus on the retina is altered to mimic changes in fixational control. We showed that visual sensitivity closely follows the strength of the luminance modulations delivered within a narrow temporal bandwidth, so changes in fixational motion have opposite visual effects at low and high spatial frequencies. By identifying a key role for oculomotor activity in spatial selectivity, these findings have important implications for the perceptual consequences of abnormal eye movements, the sources of perceptual variability, and the function of oculomotor control.

Coexistence of state, choice, and sensory integration coding in barrel cortex LII/III

During perceptually guided decisions, correlates of choice are found as upstream as in the primary sensory areas. However, how well these choice signals align with early sensory representations, a prerequisite for their interpretation as feedforward substrates of perception, remains an open question. We designed a two alternative forced choice task (2AFC) in which male mice compared stimulation frequencies applied to two adjacent vibrissae. The optogenetic silencing of individual columns in the primary somatosensory cortex (wS1) resulted in predicted shifts of psychometric functions, demonstrating that perception depends on focal, early sensory representations. Functional imaging of layer II/III single neurons revealed mixed coding of stimuli, choices and engagement in the task. Neurons with multi-whisker suppression display improved sensory discrimination and had their activity increased during engagement in the task, enhancing selectively representation of the signals relevant to solving the task. From trial to trial, representation of stimuli and choice varied substantially, but mostly orthogonally to each other, suggesting that perceptual variability does not originate from wS1 fluctuations but rather from downstream areas. Together, our results highlight the role of primary sensory areas in forming a reliable sensory substrate that could be used for flexible downstream decision processes.

Climate Change: An Obvious Phenomenon or Myth, in the African Context

Climate change is a global phenomenon of unprecedented consequence, engendering substantial scientific, political, and societal discourse. This literature review article offers an exploration of climate change perceptions and realities in the African context. It begins by establishing the unmistakable scientific consensus, with the Intergovernmental Panel on Climate Change (IPCC) serving as a primary authority. The review highlights robust evidence, including temperature trends, extreme weather events, and ecological impacts across the African continent, affirming climate change as an undeniable scientific phenomenon. However, the discourse surrounding climate change in Africa is not homogeneous. Dissenting arguments challenging climate change as a myth emphasize the variability in public perception, data limitations, and the complexities of attribution. These counterarguments reflect diverse perspectives, economic interests, and political inclinations, contributing to the multifaceted character of the climate change discussion. The implications of these findings are substantial, especially for a region highly susceptible to climate change impacts. Proactive measures for climate mitigation and adaptation are imperative to address the vulnerabilities experienced by communities, ecosystems, and economies. A multidisciplinary approach is underscored, recognizing climate change as an intricate challenge interwoven with economics, politics, and human behaviour. The diversity of voices in this discourse emphasizes the need for ongoing research, collaborative efforts, and an inclusive approach to policy formulation. In navigating the complex terrain of climate change, unwavering commitment to scientific rigor, transparency, and sustainable solutions is paramount. This literature review contributes to the ongoing dialogue, providing a basis for further inquiry and informed decision-making. It has the potential to guide future investigations, shape public policy, and elevate awareness regarding the critical significance of addressing climate change in the African context and, by extension, the entire world. The findings presented here are a testament to the indispensable role of rigorous scholarship in comprehending and confronting one of the most pressing challenges of our time

Touch me or touch me not: Emotion regulation by affective touch in human adults.

In mammals, including humans, affective touch (AT) supports the establishment and maintenance of social connections and mitigates the effects of social conflict and ostracism. AT is used to describe slowly moving, low-forced mechanical stimulation that is frequently perceived as pleasant. In humans, AT has been addressed particularly for its role in promoting bonding and emotional regulation during early development; however, more recent studies have suggested that AT also preserves physical and emotional well-being in adulthood. Here, we investigated whether AT can buffer adults' experience of negative emotions as reflected in their behavioral and physiological responses to emotionally arousing stimuli. Participants were stimulated on their forearms using AT or tapping (T) while they viewed a series of emotionally arousing and neutral images, and we measured their skin conductance response and their explicit rating of the images' unpleasantness. We found that AT, but not T, reduced the arousal and perceived unpleasantness of the emotional stimuli but not the neutral ones, revealing the soothing role of AT in emotional contexts. The second aim of the study was to explore the possibility that AT might benefit some individuals more than others, according to their individual differences. To this aim, we assessed individuals' empathy and sensory processing sensitivity, as well as their perception of AT itself. Results revealed that while empathy did not predict changes in emotional processing irrespective of tactile stimulation, individuals with higher sensitivity reported AT as less pleasant. We discuss the possible factors mediating the observed interindividual variability in AT perception. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

Evaluation of pain level during microfocused ultrasound treatment in the lower eyelid and lateral eye region: an observational study

Microfocused ultrasound is a non-invasive technology widely used for its ability to stimulate collagen production, generate fat lipolysis and provide lifting. Despite its benefits, many patients avoid the procedure due to the associated pain and discomfort. The aim of this study was to quantitatively evaluate the pain perceived during the application of HIPRO microfocused ultrasound to the lower eyelids and sides of the eyes, using the numerical pain scale (NRS). The sample consisted of 10 individuals aged between 30 and 50. The methodology included the application of HIPRO at a frequency of 10Hz and a depth of 1.5mm, with 900 shots per treated area. Pain was measured after 450 and 900 shots. The results showed that the majority of patients rated their pain as mild or non-existent, with an average score of 1.175 out of 10 on the NRS. The variability in pain perception reinforces the importance of personalized approaches. Compared to other devices, HIPRO proved to be an effective and relatively comfortable alternative, especially for pain-sensitive patients. It is concluded that HIPRO microfocused ultrasound is a safe and effective option for facial rejuvenation, with a manageable discomfort profile and good clinical results.

Social Perception in the Infant Brain and Its Link to Social Behavior.

The current longitudinal study (n = 98) utilized a developmental cognitive neuroscience approach to examine whether and how variability in social perception is linked to social behavior in early human development. Cortical responses to processing dynamic faces were investigated using functional near-infrared spectroscopy at 7 months. Individual differences in sociability were measured using the Early Childhood Behavior Questionnaire at 18 months. Confirming previous work with infants and adults, functional near-infrared spectroscopy results show that viewing changing faces recruited superior temporal cortices in 7-month-old infants, adding to the view that this brain system is specialized in social perception from early in ontogeny. Our longitudinal results show that greater engagement of the right superior temporal cortex at 7 months predicts higher levels of sociability at 18 months. This suggests that early variability in social perception is linked to later differences in overtly displayed social behavior, providing novel longitudinal evidence for a social brain-behavior association.