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Objectives: Speech intelligibility is supported by the sound of a talker's voice and visual cues related to articulatory movements. The relative contribution of auditory and visual cues to an integrated audiovisual percept varies depending on a listener's environment and sensory acuity. Cochlear implant users rely more on visual cues than those with acoustic hearing to help compensate for the fact that the auditory signal produced by their implant is poorly resolved relative to that of the typically developed cochlea. The relative weight placed on auditory and visual speech cues can be measured by presenting discordant cues across the two modalities and assessing the resulting percept (the McGurk effect). The current literature is mixed with regards to how cochlear implant users respond to McGurk stimuli; some studies suggest they report hearing syllables that represent a fusion of the auditory and visual cues more frequently than typical hearing controls while others report less frequent fusion. However, several of these studies compared implant users to younger control samples despite evidence that the likelihood and strength of audiovisual integration increase with age. Thus, the present study sought to clarify the impacts of hearing status and age on multisensory speech integration using a combination of behavioral analyses and response modeling., Design: Cochlear implant users (mean age = 58.9 years), age-matched controls (mean age = 61.5 years), and younger controls (mean age = 25.9 years) completed an online audiovisual speech task. Participants were shown and/or heard four different talkers producing syllables in auditory-alone, visual-alone, and incongruent audiovisual conditions. After each trial, participants reported the syllable they heard or saw from a list of four possible options., Results: The younger and older control groups performed similarly in both unisensory conditions. The cochlear implant users performed significantly better than either control group in the visual-alone condition. When responding to the incongruent audiovisual trials, cochlear implant users and age-matched controls experienced significantly more fusion than younger controls. When fusion was not experienced, younger controls were more likely to report the auditorily presented syllable than either implant users or age-matched controls. Conversely, implant users were more likely to report the visually presented syllable than either age-matched controls or younger controls. Modeling of the relationship between stimuli and behavioral responses revealed that younger controls had lower disparity thresholds (i.e., were less likely to experience a fused audiovisual percept) than either the implant users or older controls, while implant users had higher levels of sensory noise (i.e., more variability in the way a given stimulus pair is perceived across multiple presentations) than age-matched controls., Conclusions: Our findings suggest that age and cochlear implantation may have independent effects on McGurk effect perception. Noisy encoding of disparity modeling confirms that age is a strong predictor of an individual's prior likelihood of experiencing audiovisual integration but suggests that hearing status modulates this relationship due to differences in sensory noise during speech encoding. Together, these findings demonstrate that different groups of listeners can arrive at similar levels of performance in different ways, and highlight the need for careful consideration of stimulus- and group-related effects on multisensory speech perception., Competing Interests: The authors have no conflicts of interest to disclose., (Copyright © 2024 The American Auditory Society.)

Older adults experience a greater benefit from multisensory integration than their younger counterparts, but it is unclear why. One hypothesis is that age-related sensory decline weakens unisensory stimulus effectiveness, causing a boost in multisensory gain through inverse effectiveness. Many previous studies present stimuli at the same intensity for both younger and older adults (i.e., stimulus-matched), as opposed to accounting for each participant's unique perceptual ability (i.e., perception-matched). This makes it difficult to discern the source of age-related differences in multisensory gain. As such, we used two experiments to examine whether sensory decline is contributing to age-related differences in multisensory gain. In the first, we presented auditory (pure tones in noise), visual (Gabor patches in noise), and audiovisual stimuli and recorded response times from 31 younger (18-25) and 30 older (55-80) adults. Importantly, all participants were given identical stimuli, with the expectation that older adults would show worse unisensory performance, inducing inverse effectiveness. The second task was identical (younger N = 31, older N = 34), except stimuli were presented at each participant's 50% detection threshold, identified with an adaptive psychophysical staircase, controlling for any influence of inverse effectiveness. Older adults were found to exhibit greater multisensory gain (as measured by race model violations) on stimulus- but not perception-matched tasks, thus aligning with the principle of inverse effectiveness. That is, when accounting for potential age-related differences in perceptual abilities, older adults no longer experienced greater benefit from multisensory integration. These two experiments together suggest that the age-related increases in multisensory integration previously reported may be in part due to age-related declines in vision and audition. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

Objectives: Attention-deficit/hyperactivity disorder (ADHD) is the most common neurodevelopmental condition and is characterized by inattention, hyperactivity, and impulsivity. Research suggests that some populations, such as females and individuals with high intelligence quotients may be a risk for late ADHD diagnosis and subsequent treatment. Our goal is to advance our understanding of ADHD diagnosis, by examining (1) how child sex and cognitive abilities together are related to the age of diagnosis and (2) whether symptom presentation, current internalizing and externalizing symptoms, and demographic factors are related to age of diagnosis., Methods: Our analyses contained children who completed the required tests (N = 568) from a pre-existing dataset of 1380 children with ADHD from the Province of Ontario Neurodevelopmental Disorders (POND) Network (pond-network.ca). First, we conducted a moderation analysis with sex as the predictor, cognitive abilities as the moderator, and age of diagnosis as the outcome. Second, we conducted correlation analyses examining how symptom presentation, current internalizing and externalizing symptoms, and demographic factors are related to age of diagnosis., Results: Higher IQ was related to a later age of diagnosis. Higher hyperactive-impulsive symptoms and externalizing symptoms were related to an earlier age of diagnosis. Internalizing symptoms were trend associated with a later age of diagnosis in girls. Higher socioeconomic status and non-White maternal ethnicity were related to later age of diagnosis., Conclusions: IQ, sex, ADHD symptomology, internalizing symptoms, externalizing symptoms, and socio-demographic factors affect the age of diagnosis., (© 2024 The Author(s). British Journal of Clinical Psychology published by John Wiley & Sons Ltd on behalf of British Psychological Society.)

Face-to-face speech communication is an audiovisual process during which the interlocuters use both the auditory speech signals as well as visual, oral articulations to understand the other. These sensory inputs are merged into a single, unified process known as multisensory integration. Audiovisual speech integration is known to be influenced by many factors, including listener experience. In this study, we investigated the roles of bilingualism and language experience on integration. We used a McGurk paradigm in which participants were presented with incongruent auditory and visual speech. This included an auditory utterance of 'ba' paired with visual articulations of 'ga' that often induce the perception of 'da' or 'tha', a fusion effect that is strong evidence of integration, as well as an auditory utterance of 'ga' paired with visual articulations of 'ba' that often induce the perception of 'bga', a combination effect that is weaker evidence of integration. We compared fusion and combination effects on three groups ( N = 20 each), English monolinguals, Spanish-English bilinguals, and Arabic-English bilinguals, with stimuli presented in all three languages. Monolinguals exhibited significantly stronger multisensory integration than bilinguals in fusion effects, regardless of the stimulus language. Bilinguals exhibited a nonsignificant trend by which greater experience led to increased integration as measured by fusion. These results held regardless of whether McGurk presentations were presented as stand-alone syllables or in the context of real words.

The structure of event knowledge plays a critical role in prediction, reconstruction of memory for personal events, construction of possible future events, action, language usage, and social interactions. Despite numerous theoretical proposals such as scripts, schemas, and stories, the highly variable and rich nature of events and event knowledge have been formidable barriers to characterizing the structure of event knowledge in memory. We used network science to provide insights into the temporal structure of common events. Based on participants' production and ordering of the activities that make up events, we established empirical profiles for 80 common events to characterize the temporal structure of activities. We used the event networks to investigate multiple issues regarding the variability in the richness and complexity of people's knowledge of common events, including: the temporal structure of events; event prototypes that might emerge from learning across many experiential instances and be expressed by people; the degree to which scenes (communities) are present in various events; the degree to which people believe certain activities are central to an event; how centrality might be distributed across an event's activities; and similarities among events in terms of their content and their temporal structure. Thus, we provide novel insights into human event knowledge, and describe 18 predictions for future human studies., Competing Interests: Declaration of competing interest None. No AI and AI-assisted technologies were used in the writing process., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Youth diagnosed with Attention-Deficit/Hyperactivity Disorder (ADHD) often show deficits in various measures of higher-level cognition, such as, executive functioning. Poorer cognitive functioning in children with ADHD has been associated with differences in functional connectivity across the brain. However, little is known about the developmental changes to the brain's functional properties linked to different cognitive abilities in this cohort. To characterize these changes, we analyzed fMRI data (ADHD = 373, NT = 106) collected while youth between the ages of 6 and 16 watched a short movie-clip. We applied machine learning models to identify patterns of network connectivity in response to movie-watching that differentially predict cognitive abilities in our cohort. Using out-of-sample cross validation, our models successfully predicted IQ, visual spatial, verbal comprehension, and fluid reasoning in children (ages 6 - 11), but not in adolescents with ADHD (ages 12-16). Connections with the default mode, memory retrieval, and dorsal attention were driving prediction during early and middle childhood, but connections with the somatomotor, cingulo-opercular, and frontoparietal networks were more important in middle childhood. This work demonstrated that machine learning approaches can identify distinct functional connectivity profiles associated with cognitive abilities at different developmental stages in children and adolescents with ADHD., Competing Interests: Declaration of Competing Interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests Bobby Stojanoski reports financial support was provided by Natural Sciences and Engineering Research Council of Canada. If there are other authors, they declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Research has indicated that second-language learners have difficulty producing geminates accurately. Previous studies have also shown an effect of orthography on second-language speech production. We tested whether the existence of a contrast in the first language phonology for length aids the second-language production of the same contrast. Furthermore, we examined the effect of exposure to orthographic input on geminate consonant production in a cross-script context. We tested the production of Arabic geminate-singleton stop consonants [/bː/-/b/, /tː/-/t/, /dː/-/d/, and /kː/-/k/], a nasal stop consonant /mː/-/m/, and an emphatic stop consonant /tˤː/-/tˤ/, as well as the effect of the diacritic used in Arabic to mark gemination in a delayed imitation task and two reading tasks (ortho-with diacritics and ortho-without diacritics). A comparison of the productions of advanced Japanese-speaking learners, English-speaking learners, and an Arabic control group showed that both learner groups were able to produce Arabic geminate stops; however, the Japanese-speaking learners exhibited an advantage over the English-speaking learners in the auditory-only task and in the presence of diacritics, highlighting the fact that orthographic effects may occur in some cross-script contexts.

Background: Impairing repetitive behaviors are one of the core diagnostic symptoms in autism spectrum disorder and obsessive-compulsive disorder, but they also manifest in attention-deficit/hyperactivity disorder. Although the dorsal striatal circuit has been implicated in repetitive behaviors, extensive heterogeneity in and cross-diagnostic manifestations of these behaviors have suggested phenotypic and likely neurobiological heterogeneity across neurodevelopmental disorders (NDDs)., Methods: Intrinsic dorsal striatal functional connectivity was examined in 3 NDDs (autism spectrum disorder, obsessive-compulsive disorder, and attention-deficit/hyperactivity disorder) and typically developing control participants in a large single-cohort sample (N = 412). To learn how diagnostic labels and overlapping behaviors manifest in dorsal striatal functional connectivity measured with functional magnetic resonance imaging, the main and interaction effects of diagnosis and behavior were examined in 8 models (2 seed functional connectivity [caudate and putamen] × 4 sub-behavioral domains [sameness/ritualistic, self-injury, stereotypy, and compulsions])., Results: The obsessive-compulsive disorder group demonstrated distinctive patterns in visual and visuomotor coordination regions compared with the other diagnostic groups. Lower-order repetitive behaviors (self-injury and stereotypy) manifesting across all participants were implicated in regions involved in motor and cognitive control, although the findings did not survive effects of multiple comparisons, suggesting heterogeneity in these behavioral domains. An interaction between self-injurious behavior and an attention-deficit/hyperactivity disorder diagnosis were observed on caudate-cerebellum functional connectivity., Conclusions: These findings confirmed high heterogeneity and overlapping behavioral manifestations in NDDs and their complex underlying neural mechanisms. A call for diagnosis-free symptom measures that can capture not only observable symptoms and severity across NDDs but also the underlying functions and motivations of such behaviors across diagnoses is needed., (Copyright © 2024. Published by Elsevier Inc.)

Background: Travellers' Diarrhoea (TD) continues to be the most common travel-related medical event in international travellers. Updated incidence and risk factor data will improve pre-travel medical advice for travellers from high-income countries (HIC), providing an opportunity for disease prevention, and appropriate disease management., Methods: A systematic search for cohort studies of TD incidence published between 1 January 1997 and 2 March 2023 was performed using Ovid Medline, SCOPUS, and Google Scholar databases. Study quality was assessed with a modified Newcastle-Ottawa scale (NOS). We extracted incidence data for adults travelling less than 100 days from HIC and available risk factor data. The overall random-effects pooled incidence and the corresponding 95% confidence intervals (95% CI) were estimated. Heterogeneity was assessed using the I2 statistic, tau and the 95% prediction intervals. Subgroup analyses were conducted to identify sources of heterogeneity. Risk factor studies were reviewed qualitatively and described., Results: Ten studies were included in the meta-analysis, containing 8478 participants. Two of the studies measured as high quality and eight as good quality as assessed by the modified NOS. The TD incidence was 36.1% (95% CI 24-41%; I2 94%), with a prediction interval ranging from 20.3% to 55.8%. The pooled incidence of mild, moderate, and severe TD was 23.6%, 8.1% and 2.9%, respectively. Subgroup analysis showed that the incidence increased with increasing average data collection period. Risk factors for TD in travellers from HIC identified include younger age, longer travel periods, low and middle-income destinations, travelling for tourism, backpacking travel styles and pre-travel health status., Conclusion: It is estimated that between 20 to 56% of international travellers can expect to develop TD in travel of under 100 days. While most cases are mild, approximately 3% of all travellers will experience a disease that prevents usual activities or requires medical attention., (© The Author(s) 2024. Published by Oxford University Press on behalf of International Societyof Travel Medicine.)

Sensory processing abilities are highly variable within and across people diagnosed with autism and attention-deficit/hyperactivity disorder (ADHD). This study examined the transdiagnostic nature of sensory processing abilities, and their association with features of autism and ADHD, in a large sample of autistic people (n = 495) and people with ADHD (n = 461). Five similar data-driven sensory phenotypes characterized sensory processing abilities, and showed similar patterns of association with features of autism and ADHD, across both diagnostic groups. These results demonstrate the transdiagnostic nature of sensory processing abilities, while contributing to a growing body of literature that suggests the autism and ADHD diagnostic labels have poor explanatory power., (© 2022. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

This review aimed to explore the current understanding of sensory gating in neurodevelopmental disorders as a possible transdiagnostic mechanism. We applied methods according to the Joanna Briggs Institute Manual for Evidence Synthesis, following the population, concept, and context scoping review eligibility criteria. Using a comprehensive search strategy in five relevant research databases (Medline, EMBASE, CINAHL, PsychInfo, and Scopus), we searched for relevant peer-reviewed, primary research articles and unpublished data. Two independent reviewers screened the titles and abstracts, full-texts, and completed data extraction. We identified a total of 81 relevant articles and used descriptive analyses to summarize the characteristics and outcomes of all identified studies. Literature regarding sensory gating was most common in autistic populations with relatively fewer studies examining attention-deficit/hyperactivity disorder, tic disorders, and childhood-onset fluency disorder (COFD). The methods to assess sensory gating varied widely both within and between groups and included measures such as habituation, prepulse inhibition, affect-modulated inhibition, medication and other intervention trials. Most consistently, when participants complete questionnaires about their sensory experiences, those who have neurodevelopmental disorders report differences in their sensory gating. Affect-modulated inhibition appears to be discrepant between samples with and without neurodevelopmental disorder diagnoses. Habituation was the most commonly reported phenomenon and many differences in habituation have been found in autistic individuals and individuals with tic disorders whereas concerns with inhibition seemed more common in COFD. Overall, the evidence is inconsistent within and between disorders suggesting there is still much to learn about sensory gating in neurodevelopmental disorders., (© 2023. Crown.)

The reduction in spectral resolution by cochlear implants oftentimes requires complementary visual speech cues to facilitate understanding. Despite substantial clinical characterization of auditory-only speech measures, relatively little is known about the audiovisual (AV) integrative abilities that most cochlear implant (CI) users rely on for daily speech comprehension. In this study, we tested AV integration in 63 CI users and 69 normal-hearing (NH) controls using the McGurk and sound-induced flash illusions. To our knowledge, this study is the largest to-date measuring the McGurk effect in this population and the first that tests the sound-induced flash illusion (SIFI). When presented with conflicting AV speech stimuli (i.e., the phoneme "ba" dubbed onto the viseme "ga"), we found that 55 CI users (87%) reported a fused percept of "da" or "tha" on at least one trial. After applying an error correction based on unisensory responses, we found that among those susceptible to the illusion, CI users experienced lower fusion than controls-a result that was concordant with results from the SIFI where the pairing of a single circle flashing on the screen with multiple beeps resulted in fewer illusory flashes for CI users. While illusion perception in these two tasks appears to be uncorrelated among CI users, we identified a negative correlation in the NH group. Because neither illusion appears to provide further explanation of variability in CI outcome measures, further research is needed to determine how these findings relate to CI users' speech understanding, particularly in ecological listening conditions that are naturally multisensory.

Event knowledge, a person's understanding of patterns of activities in the world, is crucial for everyday social interactions. Social communication differences are prominent in autism, which may be related to atypical event knowledge, such as atypical knowledge of the sequences of activities that comprise the temporal structure of events. Previous research has found that autistic individuals have atypical event knowledge, but research in this area is minimal, particularly regarding autistic individuals' knowledge of the temporal structure of events. Furthermore, no studies have investigated the link between event knowledge and autistic traits in a non-clinical sample. We investigated relationships between event knowledge and autistic traits in individuals from the general population with varying degrees of autistic traits. We predicted that atypical ordering of event activities is related to autistic traits, particularly social communication abilities, but not other clinical traits. In Study 1, atypical ordering of event activities correlated with social ability, but not with most measures of repetitive behaviours and restricted interests. In Study 2, the typicality of activity ordering varied by participants' social ability and the social nature of the events. Relationships were not found between event activity ordering and other clinical traits. These findings suggest a relationship between autistic traits, specifically social abilities, and knowledge of the temporal structure of events in a general population sample., Competing Interests: Declaration of competing interest All authors declare no conflicts of interest., (Copyright © 2022 The Authors. Published by Elsevier B.V. All rights reserved.)

Integrating sensory information from multiple modalities leads to more precise and efficient perception and behaviour. The process of determining which sensory information should be perceptually bound is reliant on both low-level stimulus features, as well as multisensory associations learned throughout development based on the statistics of our environment. Here, we explored the relationship between multisensory associative learning and multisensory integration using encephalography (EEG) and behavioural measures. Sixty-one participants completed a three-phase study. First, participants were exposed to novel audiovisual shape-tone pairings with frequent and infrequent stimulus pairings and completed a target detection task. EEG recordings of the mismatch negativity (MMN) and P3 were calculated as neural indices of multisensory associative learning. Next, the same learned stimulus pairs were presented in audiovisual as well as unisensory auditory and visual modalities while both early (<100 ms) and late neural indices of multisensory integration were recorded. Finally, participants completed an analogous behavioural speeded-response task, with behavioural indices of multisensory gain calculated using the Race Model. Significant relationships were found in fronto-central and occipital areas between neural measures of associative learning and both early and late indices of multisensory integration in frontal and centro-parietal areas, respectively. Participants who showed stronger indices of associative learning also exhibited stronger indices of multisensory integration of the stimuli they learned to associate. Furthermore, a significant relationship was found between neural index of early multisensory integration and behavioural indices of multisensory gain. These results provide insight into the neural underpinnings of how higher-order processes such as associative learning guide multisensory integration., (Crown Copyright © 2022. Published by Elsevier Ltd. All rights reserved.)

Sensory issues are highly prevalent in autism and previous findings support a relationship between questionnaires of sensitivity and autistic symptoms and traits, whereas studies that examine this relationship through behavioural assessments of sensitivity are less consistent. The current study explores these differences and suggests that behavioural thresholds for sensitivity and subjective sensitivity are distinct constructs. One hundred and eighteen adults completed a visual and auditory detection task and questionnaires on sensory processing and autistic traits. Visual thresholds and subjective visual sensitivity were not correlated, but both were related to autistic traits. Auditory thresholds and subjective auditory sensitivity were also unrelated. Overall, sensitivity is highly associated with autistic traits, however, behavioural and questionnaire assessments lack convergent validity and therefore, likely assess distinct constructs., (© 2021. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)