Variation In Perception Research Articles

Letter-Like Shape Recognition in Preschool Children: Does Graphomotor Knowledge Contribute?

Based on evidence that learning new characters through handwriting leads to better recognition than learning through typing, some authors proposed that the graphic motor plans acquired through handwriting contribute to recognition. More recently two alternative explanations have been put forward. First, the advantage of handwriting could be due to the perceptual variability that it provides during learning. Second, a recent study suggests that detailed visual analysis might be the source of the advantage of handwriting over typing. Indeed, in that study, handwriting and composition –a method requiring a detailed visual analysis but no specific graphomotor activity– led to equivalent recognition accuracy, both higher than typing. The aim of the present study was to assess whether the contribution of detailed visual analysis is observed in preschool children and to test the variability hypothesis. To that purpose, three groups of preschool children learned new symbols either by handwriting, typing, or composition. After learning, children performed first a four-alternative recognition task and then a categorization task. The same pattern of results as the one observed in adults emerged in the four-alternative recognition task, confirming the importance of the detailed visual analysis in letter-like shape learning. In addition, results failed to reveal any difference across learning methods in the categorization task. The latter results provide no evidence for the variability hypothesis which would predict better categorization after handwriting than after typing or composition.

Neuroepigenetic impact on mentalizing in childhood

Mentalizing, or the ability to understand the mental states and intentions of others, is an essential social cognitive function that children learn and continue to cultivate into adolescence. While most typically developing children acquire sufficient mentalizing skills, individual differences in mentalizing persist throughout childhood and are likely influenced by a combination of cognitive functioning, the social environment, and biological factors. DNA methylation of the oxytocin receptor gene (OXTRm) impacts gene expression and is associated with increased brain activity in mentalizing regions during displays of animacy in healthy young adults. The establishment, fine-tuning, and implications of such associations in the context of broader social functioning remain unclear. Using a developmental neuroimaging epigenetic approach, we investigated the contributions of OXTRm to individual variability in brain function during animate motion perception in middle childhood. We find that higher levels of OXTRm are associated with increased neural responses in the left temporo-parietal junction and inferior frontal gyrus. We also find a positive association between neural activity in LTPJ and social skills. These findings provide evidence of epigenetic influence on the developing child brain and demonstrate that variability in neural social perception in childhood is multifaceted with contributions from individual social experience and the endogenous oxytocin system.

Arousal States as a Key Source of Variability in Speech Perception and Learning

The human brain exhibits the remarkable ability to categorize speech sounds into distinct, meaningful percepts, even in challenging tasks like learning non-native speech categories in adulthood and hearing speech in noisy listening conditions. In these scenarios, there is substantial variability in perception and behavior, both across individual listeners and individual trials. While there has been extensive work characterizing stimulus-related and contextual factors that contribute to variability, recent advances in neuroscience are beginning to shed light on another potential source of variability that has not been explored in speech processing. Specifically, there are task-independent, moment-to-moment variations in neural activity in broadly-distributed cortical and subcortical networks that affect how a stimulus is perceived on a trial-by-trial basis. In this review, we discuss factors that affect speech sound learning and moment-to-moment variability in perception, particularly arousal states—neurotransmitter-dependent modulations of cortical activity. We propose that a more complete model of speech perception and learning should incorporate subcortically-mediated arousal states that alter behavior in ways that are distinct from, yet complementary to, top-down cognitive modulations. Finally, we discuss a novel neuromodulation technique, transcutaneous auricular vagus nerve stimulation (taVNS), which is particularly well-suited to investigating causal relationships between arousal mechanisms and performance in a variety of perceptual tasks. Together, these approaches provide novel testable hypotheses for explaining variability in classically challenging tasks, including non-native speech sound learning.

Assessment of risk perception and risk communication regarding COVID-19 among healthcare providers: An explanatory sequential mixed-method study in Bangladesh

Background: Any public health emergency demands adequate risk communication with the vulnerable population along with their optimized perception about the impending risk to ensure proper risk management and crisis control. Hence, we conducted this study to explore healthcare providers' perceptions regarding risks of coronavirus disease 2019 (COVID-19), as well as how they are being communicated to about the risk, and how they practice risk reduction measures. Methods: We conducted a two-phased explanatory sequential mixed-method study among physicians and nurses from randomly selected tertiary healthcare facilities in Dhaka, the capital of Bangladesh. In the first phase, we assessed the general pattern and quantifiable measures of risk perception, risk communication, and infection prevention practices quantitatively. We performed multiple linear regression analyses to explore how much variability of risk perception was predicted by risk communication methods and contents. In the second phase, we collected qualitative data for in-depth understanding and exploration of participants' experiences and insights regarding COVID-19 risk through interviews and document reviews. We manually performed thematic content analysis of the qualitative data. Finally, we triangulated findings from both phases to illustrate the research objectives. Discussion: Based on the psychometric dimensions of risk perception and psycho-social theory of the health belief model, perceptions of COVID-19 risk among healthcare providers were evaluated in this study. The relationship between risk perception and infection prevention and control practices among healthcare providers were also investigated. The explanatory sequential design of this study is expected to generate hypotheses on how risk perception is being shaped in a time of uncertainty and, thus, will help to build a proper risk communication strategy for the healthcare providers.

Single-Channel Focused Thresholds Relate to Vowel Identification in Pediatric and Adult Cochlear Implant Listeners.

Speech recognition outcomes are highly variable among pediatric and adult cochlear implant (CI) listeners. Although there is some evidence that the quality of the electrode-neuron interface (ENI) contributes to this large variability in auditory perception, its relationship with speech outcomes is not well understood. Single-channel auditory detection thresholds measured in response to focused electrical fields (i.e., focused thresholds) are sensitive to properties of ENI quality, including electrode-neuron distance, intracochlear resistance, and neural health. In the present study, focused thresholds and speech perception abilities were assessed in 15 children and 21 adult CI listeners. Focused thresholds were measured for all active electrodes using a fast sweep procedure. Speech perception performance was evaluated by assessing listeners’ ability to identify vowels presented in /h-vowel-d/ context. Consistent with prior literature, focused thresholds were lower for children than for adults, but vowel identification did not differ significantly across age groups. Higher across-array average focused thresholds, which may indicate a relatively poor ENI quality, were associated with poorer vowel identification scores in both children and adults. Adult CI listeners with longer durations of deafness had higher focused thresholds. Findings from this study demonstrate that poor-quality ENIs may contribute to reduced speech outcomes for pediatric and adult CI listeners. Estimates of ENI quality (e.g., focused thresholds) may assist in developing customized programming interventions that serve to improve the transmission of spectral cues that are important in vowel identification.

Farmers’ Perception about Climate Change and Response Strategies

The crop production response strategies to climate change and variability vis-à-vis theirsocio-personal characteristics in North-Eastern Karnataka region were identified andanalysed. A multi-stage random sampling technique was employed to elicit informationfrom 120 respondents. Ex-post-facto research design was adopted as manifestation of eventwas already accrued. Data were collected through a pre-tested semi-structured questionnaireTotal 52 strategies were collected from different literature, website, thesis etc., and testedamong the respondents. The study revealed that there were eight commonly adopted cropproduction response strategies which were scrutinsed from the 30 selected strategies usingprincipal component analysis namely, soil-water retention and integrated farming, followedby, contingency crop planning, crop diversification and risk aversion strategies, seekingadvice from extension personnel and others, improving irrigation facilities, maintaininglivestock, crop insurance, and migration to cities. The farmers’ education, mass media useand source of weather information were significantly contributed in their perception aboutclimate change and variability at 5% level of probability.

Sexuality Discourses and LGBQ Students’ Interpretations of Campus Climate in the Contemporary US

ABSTRACT Recent US studies showed that perceptions of campus climate vary considerably across individual LGBQ students, with some students reporting friendly climates and others reporting persistent hostility. Although researchers have identified several factors that contribute to the perceptual variations, they have paid limited attention to the role of sexuality discourses. The present study sought to fill this gap in the literature by analyzing in-depth interviews. The analysis showed that LGBQ students drew on two major discourses to guide their interpretations of campus climate. A majority of students drew on post-closet discourse to celebrate their visibility on campus, LGBQ-friendly courses, and straight classmates’ positive reactions. A smaller number of students drew on queer discourse to question the meaning of LGBQ students’ visibility and criticize heterosexist biases in classrooms. Overall, these results highlighted the importance of the competing discourses, which set LGBQ students’ expectations and guided their interpretations of campus experiences.

Assessment of risk perception and risk communication regarding COVID-19 among healthcare providers: An explanatory sequential mixed-method study in Bangladesh

Background: Any public health emergency demands adequate risk communication with the vulnerable population along with their optimized perception about the impending risk to ensure proper risk management and crisis control. Hence, we conducted this study to explore healthcare providers’ perceptions regarding risks of coronavirus disease 2019 (COVID-19), as well as how they are being communicated to about the risk, and how they practice risk reduction measures. Methods: We conducted a two-phased explanatory sequential mixed-method study among physicians and nurses from randomly selected tertiary healthcare facilities in Dhaka, the capital of Bangladesh. In the first phase, we assessed the general pattern and quantifiable measures of risk perception, risk communication, and infection prevention practices quantitatively. We performed multiple linear regression analyses to explore how much variability of risk perception was predicted by risk communication methods and contents. In the second phase, we collected qualitative data for in-depth understanding and exploration of participants’ experiences and insights regarding COVID-19 risk through interviews and document reviews. We manually performed thematic content analysis of the qualitative data. Finally, we triangulated findings from both phases to illustrate the research objectives. Discussion: Based on the psychometric dimensions of risk perception and psycho-social theory of the health belief model, perceptions of COVID-19 risk among healthcare providers were evaluated in this study. The relationship between risk perception and infection prevention and control practices among healthcare providers were also investigated. The explanatory sequential design of this study is expected to generate hypotheses on how risk perception is being shaped in a time of uncertainty and, thus, will help to build a proper risk communication strategy for the healthcare providers

Sounds familiar(?): Expertise with specific musical genres modulates timing perception and micro-level synchronization to auditory stimuli

Musical expertise improves the precision of timing perception and performance – but is this expertise generic, or is it tied to the specific style(s) and genre(s) of one’s musical training? We asked expert musicians from three musical genres (folk, jazz, and EDM/hip-hop) to align click tracks and tap in synchrony with genre-specific and genre-neutral sound stimuli to determine the perceptual center (“P-center”) and variability (“beat bin”) for each group of experts. We had three stimulus categories – Organic, Electronic, and Neutral sounds – each of which had a 2 × 2 design of the acoustic factors Attack (fast/slow) and Duration (short/long). We found significant effects of Genre expertise, and a significant interaction for both P-center and P-center variability: folk and jazz musicians synchronize to sounds typical of folk and jazz in a different manner than the EDM/hip-hop producers. The results show that expertise in a specific musical genre affects our low-level perceptions of sounds as well as their affordance(s) for joint action/synchronization. The study provides new insights into the effects of active long-term musical enculturation and skill acquisition on basic sensorimotor synchronization and timing perception, shedding light on the important question of how nature and nurture intersect in the development of our perceptual systems.

Functional variability in movement coordination and perception

Functional variability in movement coordination and perception

Intrinsic network activity reflects the ongoing experience of chronic pain

Analyses of intrinsic network activity have been instrumental in revealing cortical processes that are altered in chronic pain patients. In a novel approach, we aimed to elucidate how intrinsic functional networks evolve in regard to the fluctuating intensity of the experience of chronic pain. In a longitudinal study with 156 fMRI sessions, 20 chronic back pain patients and 20 chronic migraine patients were asked to continuously rate the intensity of their endogenous pain. We investigated the relationship between the fluctuation of intrinsic network activity with the time course of subjective pain ratings. For chronic back pain, we found increased cortical network activity for the salience network and a local pontine network, as well as decreased network activity in the anterior and posterior default mode network for higher pain intensities. Higher pain intensities in chronic migraine were accompanied with lower activity in a prefrontal cortical network. By taking the perspective of the individual, we focused on the variability of the subjective perception of pain, which include phases of relatively low pain and phases of relatively high pain. The present design of the assessment of ongoing endogenous pain can be a powerful and promising tool to assess the signature of a patient’s endogenous pain encoding.

MicroRNA Profiling in the Perilymph of Cochlear Implant Patients: Identifying Markers that Correlate to Audiological Outcomes.

MicroRNA (miRNA) expression profiles from human perilymph correlate to post cochlear implantation (CI) hearing outcomes. The high inter-individual variability in speech perception among cochlear implant recipients is still poorly understood. MiRNA expression in perilymph can be used to characterize the molecular processes underlying inner ear disease and to predict performance with a cochlear implant. Perilymph collected during CI from 17 patients was analyzed using microarrays. MiRNAs were identified and multivariable analysis using consonant-nucleus-consonant testing at 6 and 18 months post implant activation was performed. Variables analyzed included age, gender, preoperative pure tone average (PTA), and preoperative speech discrimination (word recognition [WR]). Gene ontology analysis was performed to identify potential functional implications of changes in the identified miRNAs. Distinct miRNA profiles correlated to preoperative PTA and WR. Patients classified as poor performers showed downregulation of six miRNAs that potentially regulate pathways related to neuronal function and cell survival. Individual miRNA profiles can be identified in microvolumes of perilymph. Distinct non-coding RNA expression profiles correlate to preoperative hearing and postoperative cochlear implant outcomes.

Visual dysfunction is associated with cognitive impairment in Parkinson's disease

IntroductionVisual dysfunction and cognitive impairment are common in Parkinson's disease (PD) but the precise contribution of lower-level visual impairment to visual-input based cognitive performance has not been extensively characterized in PD. MethodsWe included 49 PD patients and 22 healthy controls (HC). Lower-level visual function tests [high and low contrast visual acuity (HCVA and LCVA) and contrast sensitivity (CS)] and a neuropsychological battery (involving visual cognition) were performed. Pairwise correlations between lower-level visual functions and visual cognition were computed and stepwise linear regressions were fitted introducing age, Geriatric Depression Scale, and lower-level visual functions in the model to calculate their predicted effect on visual cognition. ResultsCompared to controls, patients presented a significant impairment in all cognitive domains (visual attention, visual processing speed and visual perception, visuospatial abilities, visuoconstructive abilities, and visual memory), and lower-level visual functions. HCVA and LCVA were significantly associated with visual cognition in PD. HCVA explained up to 49.3% and 34.2% of the variability in visual perception and visuospatial abilities, respectively, whereas LCVA was mainly associated with short- and long-term visual memory and visuospatial abilities. ConclusionLower-level visual dysfunction is highly associated with cognitive performance in PD, when cognitive tests are based on visual input. Our results support that lower-level visual functions should be considered when assessing cognitive status of PD patients and might be useful for predicting cognitive deterioration.

Distal and proximal family contextual effects on adolescents' interparental conflict appraisals: A daily diary study.

Adolescent appraisals of interparental conflict (IPC)-perceiving IPC as threatening to their well-being or that of the family, and self-blaming attributions-are well-established processes through which IPC confers risk for developmental disruptions and psychopathology. Recent work documents intraindividual change in IPC and appraisals that occur on a daily timescale. However, considerably less is known about how the broader family context may temper appraisals of IPC. This study provides a novel examination of the implications of distal (global ratings of family relationships in general) and proximal (fluctuations in daily family relationships) family context (family cohesion, parent-adolescent closeness, and parent-adolescent conflict) for adolescents' propensity to form negative appraisals of daily IPC. This sample included 144 adolescents (63% female) in two-parent families, who participated in a 21-day daily diary study. Findings indicate that intraindividual variability in adolescents' perception of family cohesion, parent-adolescent closeness, and parent-adolescent conflict all correspond to adolescent appraisals of IPC through direct relations and moderating effects. Unique patterns emerged for boys and girls, suggesting gender differences in how adolescents incorporate the family context into their appraisals of IPC. This study expands our awareness of the importance of daily fluctuations in family relationships for adolescent risk during exposure to IPC. (PsycInfo Database Record (c) 2021 APA, all rights reserved).

Alpha Oscillations Shape Sensory Representation and Perceptual Sensitivity.

Alpha activity (8-14 Hz) is the dominant rhythm in the awake brain and is thought to play an important role in setting the internal state of the brain. Previous work has associated states of decreased alpha power with enhanced neural excitability. However, evidence is mixed on whether and how such excitability enhancement modulates sensory signals of interest versus noise differently, and what, if any, are the consequences for subsequent perception. Here, human subjects (male and female) performed a visual detection task in which we manipulated their decision criteria in a blockwise manner. Although our manipulation led to substantial criterion shifts, these shifts were not reflected in prestimulus alpha band changes. Rather, lower prestimulus alpha power in occipital-parietal areas improved perceptual sensitivity and enhanced information content decodable from neural activity patterns. Additionally, oscillatory alpha phase immediately before stimulus presentation modulated accuracy. Together, our results suggest that alpha band dynamics modulate sensory signals of interest more strongly than noise.SIGNIFICANCE STATEMENT The internal state of our brain fluctuates, giving rise to variability in perception and action. Neural oscillations, most prominently in the alpha band, have been suggested to play a role in setting this internal state. Here, we show that ongoing alpha band activity in occipital-parietal regions predicts the quality of visual information decodable in neural activity patterns and subsequently the human observer's sensitivity in a visual detection task. Our results provide comprehensive evidence that visual representation is modulated by ongoing alpha band activity and advance our understanding on how, when faced with unchanging external stimuli, internal neural fluctuations influence perception and behavior.

Unifying information theory and machine learning in a model of electrode discrimination in cochlear implants.

Despite the development and success of cochlear implants over several decades, wide inter-subject variability in speech perception is reported. This suggests that cochlear implant user-dependent factors limit speech perception at the individual level. Clinical studies have demonstrated the importance of the number, placement, and insertion depths of electrodes on speech recognition abilities. However, these do not account for all inter-subject variability and to what extent these factors affect speech recognition abilities has not been studied. In this paper, an information theoretic method and machine learning technique are unified in a model to investigate the extent to which key factors limit cochlear implant electrode discrimination. The framework uses a neural network classifier to predict which electrode is stimulated for a given simulated activation pattern of the auditory nerve, and mutual information is then estimated between the actual stimulated electrode and predicted ones. We also investigate how and to what extent the choices of parameters affect the performance of the model. The advantages of this framework include i) electrode discrimination ability is quantified using information theory, ii) it provides a flexible framework that may be used to investigate the key factors that limit the performance of cochlear implant users, and iii) it provides insights for future modeling studies of other types of neural prostheses.

Motor Circuit and Superior Temporal Sulcus Activities Linked to Individual Differences in Multisensory Speech Perception.

Integrating multimodal information into a unified perception is a fundamental human capacity. McGurk effect is a remarkable multisensory illusion that demonstrates a percept different from incongruent auditory and visual syllables. However, not all listeners perceive the McGurk illusion to the same degree. The neural basis for individual differences in modulation of multisensory integration and syllabic perception remains largely unclear. To probe the possible involvement of specific neural circuits in individual differences in multisensory speech perception, we first implemented a behavioral experiment to examine the McGurk susceptibility. Then, functional magnetic resonance imaging was performed in 63 participants to measure the brain activity in response to non-McGurk audiovisual syllables. We revealed significant individual variability in McGurk illusion perception. Moreover, we found significant differential activations of the auditory and visual regions and the left Superior temporal sulcus (STS), as well as multiple motor areas between strong and weak McGurk perceivers. Importantly, the individual engagement of the STS and motor areas could specifically predict the behavioral McGurk susceptibility, contrary to the sensory regions. These findings suggest that the distinct multimodal integration in STS as well as coordinated phonemic modulatory processes in motor circuits may serve as a neural substrate for interindividual differences in multisensory speech perception.

Data-Driven Clustering Approach to Derive Taste Perception Profiles from Sweet, Salt, Sour, Bitter, and Umami Perception Scores: An Illustration among Older Adults with Metabolic Syndrome

BackgroundCurrent approaches to studying relations between taste perception and diet quality typically consider each taste—sweet, salt, sour, bitter, umami—separately or aggregately, as total taste scores. Consistent with studying dietary patterns rather than single foods or total energy, an additional approach may be to study all 5 tastes collectively as “taste perception profiles.” ObjectiveWe developed a data-driven clustering approach to derive taste perception profiles from taste perception scores and examined whether profiles outperformed total taste scores for capturing individual variability in taste perception. MethodsThe cohort included 367 community-dwelling adults [55–75 y; 55% female; BMI (kg/m2): 32.2 ± 3.6] with metabolic syndrome from PREDIMED-Plus, Valencia. Cluster analysis identified subgroups of individuals with similar patterns in taste perception (taste perception profiles); quantitative criteria were used to select the cluster algorithm, determine the optimal number of clusters, and assess the profiles’ validity and stability. Goodness-of-fit parameters from adjusted linear regression evaluated the individual variability captured by each approach. ResultsA k-means algorithm with 6 clusters best fit the data and identified the following taste perception profiles: Low All, High Bitter, High Umami, Low Bitter & Umami, High All But Bitter and High All But Umami. All profiles were valid and stable. Compared with total taste scores, taste perception profiles explained more variability in bitter and umami perception (adjusted R2: 0.19 vs. 0.63, respectively; 0.40 vs. 0.65, respectively) and were comparable for sweet, salt, and sour. In addition, taste perception profiles captured differential perceptions of each taste within individuals, whereas these patterns were lost with total taste scores. ConclusionsAmong older adults with metabolic syndrome, taste perception profiles derived via data-driven clustering may provide a valuable approach to capture individual variability in perception of all 5 tastes and their collective influence on diet quality. This trial was registered at https://www.isrctn.com/ as ISRCTN89898870.

Early auditory cortical processing predicts auditory speech in noise identification and lipreading

Individuals typically exhibit better cross-sensory perception following unisensory loss, demonstrating improved perception of information available from the remaining senses and increased cross-sensory use of neural resources. Even individuals with no sensory loss will exhibit such changes in cross-sensory processing following temporary sensory deprivation, suggesting that the brain's capacity for recruiting cross-sensory sources to compensate for degraded unisensory input is a general characteristic of the perceptual process. Many studies have investigated how auditory and visual neural structures respond to within- and cross-sensory input. However, little attention has been given to how general auditory and visual neural processing relates to within and cross-sensory perception. The current investigation examines the extent to which individual differences in general auditory neural processing accounts for variability in auditory, visual, and audiovisual speech perception in a sample of young healthy adults. Auditory neural processing was assessed using a simple click stimulus. We found that individuals with a smaller P1 peak amplitude in their auditory-evoked potential (AEP) had more difficulty identifying speech sounds in difficult listening conditions, but were better lipreaders. The results suggest that individual differences in the auditory neural processing of healthy adults can account for variability in the perception of information available from the auditory and visual modalities, similar to the cross-sensory perceptual compensation observed in individuals with sensory loss.

Relationship between anxiety, depression and health perception in patients with multimorbidity versus patients without multimorbidity

Abstract Background Multimorbidity is a public health problem. It affects more than one third of Portuguese citizens and has a negative impact on health, both physical and psychological, and quality of life of patients. This study aims to understand the relationship between anxiety, depression and health perception in patients with multimorbidity versus patients without, and to understand the possible influence of sociodemographic factors on this relationship. Methods Cross-sectional study with a convenience sample of 176 patients interviewed by telephone using a survey that included sociodemographic variables, a list of 23 diseases to determine the presence of multimorbidity and the HADS and SF-12 scales. Subsequently, descriptive and inferential statistical analysis of the data was performed to perceive if socio-demographic factors influence multimorbidity. A value of P < 0.05 was determined as statistically significant. Results The sample (n = 176) had an average age of 51.33 years, 51.1% were multi-morbid. A statistically significant difference was found between the two groups only in the perception of physical health (P < 0.001). Age (P < 0.001) and multi-morbidity (P = 0.004) were identified as significant independent predictors of physical health perception, with the regression model explaining about 43% of the variability in physical health perception of study participants. Conclusions Although this study presented some disparities with other studies, it concluded that patients with multimorbidity have a worse perception of their physical health, independently from the sociodemographic variables that were studied, except for age. The absence of a consistent definition of multimorbidity was the main limitation of the study.