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Although autism spectrum disorders (ASD) are commonly characterized by diminished episodic memory, the literature in this area is mixed. We address these inconsistent findings by employing multilevel Bayesian meta-analysis to quantify episodic memory differences between individuals with ASD and typically developing (TD) controls. We used meta-regression to evaluate the effects of test modality (e.g., word list, story recall), delay interval (immediate vs. delayed), retrieval demands (recognition vs. recall), and sensory modality (auditory vs. visual) on episodic memory in ASD. A total of 338 effect sizes from 113 empirical articles, including 5,632 unique participants (ASD = 2,777, TD = 2,855), were included. Results show that the memory deficits associated with ASD were larger for recall (g = -0.52, se = 0.04, 95% CrI [-0.60, -0.43]) compared to recognition (g = -0.25, se = 0.05, 95% CrI [-0.35, -0.14]) and differed based on the testing modality. For example, effect sizes were smallest for words (g = -0.28, se = 0.05, 95% CrI [-0.38, -0.18]), pictures (g = -0.38, se = 0.07, 95% CrI [-0.52, -0.24]), and figure reproduction (g = -0.49, se = 0.11, 95% CrI [-0.70, -0.27]). However, effect sizes for sentences (g = -0.59, se = 0.20, 95% CrI [-1.00, -0.21]), stories (Hedges' g = -0.54, se = 0.08, 95% CrI [-0.69, -0.38]) and staged events (g = -0.75, se = 0.10, 95% CrI [-0.95, -0.55]) were much larger. These findings suggest that ASD is associated with a small to medium reduction in scores on episodic memory tests relative to TD controls.
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Transtorno do Espectro Autista , Memória Episódica , Transtorno do Espectro Autista/complicações , Teorema de Bayes , Humanos , Rememoração Mental , Reconhecimento PsicológicoRESUMO
As one of the oldest plants cultivated by humans, hemp used to be banned in the United States but returned as a legal crop in 2018. Since then, the United States has become the leading hemp producer in the world. Currently, hemp attracts increasing attention from consumers and scientists as hemp products provide a wide spectrum of potential functions. Particularly, bioactive peptides derived from hemp proteins have been proven to be strong antioxidants, which is an extremely hot research topic in recent years. However, some controversial disputes and unknown issues are still underway to be explored and verified in the aspects of technique, methodology, characteristic, mechanism, application, caution, etc. Therefore, this review focusing on the antioxidant properties of hemp proteins is necessary to discuss the multiple critical issues, including in vitro structure-modifying techniques and antioxidant assays, structure-activity relationships of antioxidant peptides, pre-clinical studies on hemp proteins and pathogenesis-related molecular mechanisms, usage and potential hazard, and novel advanced techniques involving bioinformatics methodology (QSAR, PPI, GO, KEGG), proteomic analysis, and genomics analysis, etc. Taken together, the antioxidant potential of hemp proteins may provide both functional food benefits and phytotherapy efficacy to human health.
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Cannabis , Humanos , Estados Unidos , Cannabis/química , Antioxidantes/farmacologia , Alimento Funcional , Proteômica , Peptídeos/farmacologia , FitoterapiaRESUMO
Face recognition is important for primate social cognition, enabling rapid discrimination between faces and objects. In humans, face recognition is characterized by certain cognitive specializations such as face-specific sensitivity to upright faces. The face inversion effect reflects the disproportionate inversion cost (i.e., poorer recognition of inverted compared to upright stimuli) for faces compared to non-face objects. Numerous studies have evaluated the face inversion effect in various nonhuman primates, but the findings are highly variable and mixed, especially in monkeys. To address this inconsistency, the current study employed a multilevel, phylogenetic meta-analysis on 52 effect sizes across 16 studies to quantify the magnitude of the face inversion effect in nonhuman primates. Overall, the difference in inversion costs for faces compared to nonface stimuli was small but not statistically significant (b = 0.31, se = 0.16, 95% CI [- 0.01, 0.62], p = 0.06). Additionally, this did not systematically vary between the family of species (chimpanzee or monkey) or type of face stimuli (conspecific or heterospecific). Ultimately, it cannot be concluded that the face inversion effect is a reliable phenomenon in either chimpanzees or monkeys, suggesting that nonhuman primates may not use similar face-specific processing strategies as humans.
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Pan troglodytes , Filogenia , Reconhecimento Psicológico , Animais , Face , Reconhecimento Facial , Feminino , Humanos , Masculino , Pan troglodytes/psicologia , Reconhecimento Visual de Modelos , Primatas , Projetos de PesquisaRESUMO
Adolescence is a critical developmental period that is marked by drastic changes in face recognition, which are reflected in patterns of bias (i.e., superior recognition for some individuals compared to others). Here, we evaluate how race is perceived during face recognition and whether adolescents exhibit an own-race bias (ORB). We conducted a Bayesian meta-analysis to estimate the summary effect size of the ORB across 16 unique studies (38 effect sizes) with 1,321 adolescent participants between the ages of â¼10-22 years of age. This meta-analytic approach allowed us to inform the analysis with prior findings from the adult literature and evaluate how well they fit the adolescent literature. We report a positive, small ORB (Hedges's g = 0.24) that was evident under increasing levels of uncertainty in the analysis. The magnitude of the ORB was not systematically impacted by participant age or race, which is inconsistent with predictions from perceptual expertise and social cognitive theories. Critically, our findings are limited in generalizability by the study samples, which largely include White adolescents in White-dominant countries. Future longitudinal studies that include racially diverse samples and measure social context, perceiver motivation, peer reorientation, social network composition, and ethnic-racial identity development are critical for understanding the presence, magnitude, and relative flexibility of the ORB in adolescence. (PsycInfo Database Record (c) 2024 APA, all rights reserved).
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Reconhecimento Facial , Grupos Raciais , Adolescente , Criança , Humanos , Adulto Jovem , Teorema de Bayes , Grupo Associado , Reconhecimento PsicológicoRESUMO
A core feature of autism involves difficulty perceiving and interpreting eye gaze shifts as nonverbal communicative signals. A hypothesis about the origins of this phenotype is that it emerges from developmentally different social visual attention (SVA). We developed Social Games for Autistic Adolescents (SAGA; Scherf et al. BMJ Open 8(9):e023682, 2018) as a serious game intervention for autistic individuals to discover the significance of eye gaze cues. Previously, we demonstrated the effectiveness of SAGA to improve the perception and understanding of eye gaze cues and social skills for autistic adolescents (Griffin et al. JCPP Adv 1(3):e12041, 2021). Here, we determine whether increases in social visual attention to faces and/or target gazed-at objects, as measured via eye tracking during the same Gaze Perception task in the same study sample, moderated this improvement. In contrast to predictions, SVA to faces did not differentially increase for the treatment group. Instead, both groups evinced a small increase in SVA to faces over time. Second, Prior to the SAGA intervention, attention to faces failed to predict performance in the Gaze Perception task for both the treatment and standard care control groups. However, at post-test, autistic adolescents in the treatment group were more likely to identify the object of directed gaze when they attended longer to faces and longer to target objects. Importantly, this is the first study to measure social visual attention via eye tracking as a treatment response in an RCT for autism. NCT02968225.
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Transtorno Autístico , Transtornos Globais do Desenvolvimento Infantil , Humanos , Adolescente , Criança , Transtorno Autístico/terapia , Sinais (Psicologia) , Tecnologia de Rastreamento Ocular , Fixação OcularRESUMO
PURPOSE: Social anhedonia is a transdiagnostic trait that reflects reduced pleasure from social interaction. It has historically been associated with autism, however, very few studies have directly examined behavioral symptoms of social anhedonia in autistic youth. We investigated rates of social anhedonia in autistic compared to non-autistic youth and the relative contributions of autism and social anhedonia symptoms to co-occurring mental health. METHODS: Participants were 290 youth (Mage=13.75, Nautistic=155) ranging in age from 8 to 18. Youth completed a cognitive assessment and a diagnostic interview. Their caregiver completed questionnaires regarding symptoms of autism and co-occurring psychiatric conditions. RESULTS: Autistic youth were more likely to meet criteria for social anhedonia than non-autistic youth. There was a significant positive relationship between age and social anhedonia symptom severity, but there was no association between sex and social anhedonia. Dominance analysis revealed that social anhedonia symptom severity had the strongest association with symptoms of depression and social anxiety, while symptoms of ADHD, generalized anxiety, and separation anxiety were most strongly associated with autism symptom severity. CONCLUSION: This was the first study to tease out the relative importance of social anhedonia and autism symptoms in understanding psychiatric symptoms in autistic youth. Findings revealed higher rates of social anhedonia in autistic youth. Our results indicate that social anhedonia is an important transdiagnostic trait that plays a unique role in understanding co-occurring depression and social anxiety in autistic youth. Future research should utilize longitudinal data to test the transactional relationships between social anhedonia and internalizing symptoms over time.
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PURPOSE: Visual face recognition-the ability to encode, discriminate, and recognize the faces of others-is fundamentally supported by eye movements and is a common source of difficulty for autistic individuals. We aimed to evaluate how visual processing strategies (i.e., eye movement patterns) directly support encoding and recognition of faces in autistic and neurotypical (NT) individuals. METHODS: We used a hidden Markov modeling approach to evaluate the spatiotemporal dynamics of eye movements in autistic (n = 15) and neurotypical (NT) adolescents (n = 17) during a face identity recognition task. RESULTS: We discovered distinct eye movement patterns among all participants, which included a focused and exploratory strategy. When evaluating change in visual processing strategy across encoding and recognition phases, autistic individuals did not shift their eye movement patterns like their NT peers, who shifted to a more exploratory visual processing strategy during recognition. CONCLUSION: These findings suggest that autistic individuals do not modulate their visual processing strategy across encoding and recognition of faces, which may be an indicator of less efficient face processing.
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Increasing evidence suggests that specific memory systems (e.g., semantic vs. episodic) may support specific creative thought processes. However, there are a number of inconsistencies in the literature regarding the strength, direction, and influence of different memory (semantic, episodic, working, and short-term) and creativity (divergent and convergent thinking) types, as well as the influence of external factors (age, stimuli modality) on this purported relationship. In this meta-analysis, we examined 525 correlations from 79 published studies and unpublished datasets, representing data from 12,846 individual participants. We found a small but significant (r = .19) correlation between memory and creative cognition. Among semantic, episodic, working, and short-term memory, all correlations were significant, but semantic memory - particularly verbal fluency, the ability to strategically retrieve information from long-term memory - was found to drive this relationship. Further, working memory capacity was found to be more strongly related to convergent than divergent creative thinking. We also found that within visual creativity, the relationship with visual memory was greater than that of verbal memory, but within verbal creativity, the relationship with verbal memory was greater than that of visual memory. Finally, the memory-creativity correlation was larger for children compared to young adults despite no impact of age on the overall effect size. These results yield three key conclusions: (1) semantic memory supports both verbal and nonverbal creative thinking, (2) working memory supports convergent creative thinking, and (3) the cognitive control of memory is central to performance on creative thinking tasks.
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Criatividade , Pensamento , Adulto Jovem , Criança , Humanos , Cognição , Memória de Curto Prazo , Memória de Longo PrazoRESUMO
The objective of this study was to determine if supplementation and delivery method of a "stress pack" composed of organic trace minerals and Saccharomyces cerevisiae yeast culture product influenced growth performance, feed efficiency, and hepatic trace mineral concentration in newly weaned steers. Crossbred steers (nâ =â 192; 256â ±â 14.0 kg) were used in a 49-day receiving phase experiment. Within 36 hours of weaning, steers were weighed, allotted to 24 pens (nâ =â 8 steers/pen; 8 pens/treatment), and randomly assigned to treatments: 1) a traditional receiving diet (CON), 2) a traditional receiving diet plus the "stress-pack" directly in the diet (FORCE), and 3) a traditional receiving diet plus a low-moisture, cooked molasses block fortified with the "stress-pack" (TUB). The "stress-pack" was offered the first 28 day of the 49-day receiving period. Due to adverse weather conditions forecasted on day 1, biopsy samples were collected from a subsample of steers (nâ =â 14 steers) on day 1 to establish hepatic trace mineral concentration baseline. Steers were selected based on the mean body weight (BW) from allotment (day -1) of the pen for collection of subsequent samples (nâ =â 1 steer/pen) on days 14, 28, and 49 for hepatic trace mineral concentration determination. Cumulative dry matter intake (DMI) (Pâ =â 0.01) was greater for FORCE compared to CON and TUB. Final BW and average daily gain (ADG) tended (Pâ ≤â 0.10) to be greater for FORCE compared to TUB and CON by 5.4% and 9.4%, respectively. Feed efficiency did not differ between treatments (Pâ =â 0.28). A treatmentâ ×â day interaction (Pâ ≤â 0.01) for hepatic Cu concentration was noted. The FORCE treatment had greater hepatic Cu compared to TUB and CON for the entire period. The steers that received TUB had greater hepatic Cu compared to CON on days 14 and 28, but similar to CON on day 49. The addition of a "stress-pack" to diets offered to newly weaned cattle enhanced hepatic trace mineral concentration, and delivery method influences DMI and daily gain.
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Importance: Face processing is foundational to human social cognition, is central to the hallmark features of autism spectrum disorder (ASD), and shapes neural systems and social behavior. Highly efficient and specialized, the face processing system is sensitive to inversion, demonstrated by reduced accuracy in recognition and altered neural response to inverted faces. Understanding at which mechanistic level the autistic face processing system may be particularly different, as measured by the face inversion effect, will improve overall understanding of brain functioning in autism. Objective: To synthesize data from the extant literature to determine differences of the face processing system in ASD, as measured by the face inversion effect, across multiple mechanistic levels. Data Sources: Systematic searches were conducted in the MEDLINE, Embase, Web of Science, and PubMed databases from inception to August 11, 2022. Study Selection: Original research that reported performance-based measures of face recognition to upright and inverted faces in ASD and neurotypical samples were included for quantitative synthesis. All studies were screened by at least 2 reviewers. Data Extraction and Synthesis: This systematic review and meta-analysis was conducted according to the 2020 Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) reporting guideline. Multiple effect sizes were extracted from studies to maximize information gain and statistical precision and used a random-effects, multilevel modeling framework to account for statistical dependencies within study samples. Main Outcomes and Measures: Effect sizes were calculated as a standardized mean change score between ASD and neurotypical samples (ie, Hedges g). The primary outcome measure was performance difference between upright and inverted faces during face recognition tasks. Measurement modality, psychological construct, recognition demand, sample age, sample sex distribution, and study quality assessment scores were assessed as moderators. Results: Of 1768 screened articles, 122 effect sizes from 38 empirical articles representing data from 1764 individual participants (899 ASD individuals and 865 neurotypical individuals) were included in the meta-analysis. Overall, face recognition performance differences between upright and inverted faces were reduced in autistic individuals compared with neurotypical individuals (g = -0.41; SE = 0.11; 95% credible interval [CrI], -0.63 to -0.18). However, there was considerable heterogeneity among effect sizes, which were explored with moderator analysis. The attenuated face inversion effect in autistic individuals was more prominent in emotion compared with identity recognition (b = 0.46; SE = 0.26; 95% CrI, -0.08 to 0.95) and in behavioral compared with electrophysiological measures (b = 0.23; SE = 0.24; 95% CrI, -0.25 to 0.70). Conclusions and Relevance: This study found that on average, face recognition in autism is less impacted by inversion. These findings suggest less specialization or expertise of the face processing system in autism, particularly in recognizing emotion from faces as measured in behavioral paradigms.
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Transtorno do Espectro Autista , Transtorno Autístico , Reconhecimento Facial , Humanos , Reconhecimento Facial/fisiologia , Transtorno do Espectro Autista/psicologia , Teorema de Bayes , EncéfaloRESUMO
Face and body perception rely on specialized processing mechanisms to interpret social information efficiently. The body inversion effect (BIE), refers to an inversion effect for bodies, such that recognition of bodies is impaired by inversion. The BIE, like the face inversion effect (FIE), is particularly important because a disproportionate BIE relative to inversion effects for objects could be interpreted in much the same way as the disproportionate FIE has often been characterized; that is, as evidence of specialized, configural processing. However, research supporting the BIE is marked by methodological heterogeneity and mixed findings. Our multilevel Bayesian meta-analysis addresses inconsistencies in the literature by pooling data from numerous studies to estimate the magnitude of the BIE across various methodological and stimulus properties. We included 180 effect sizes from 41 empirical articles representing data from 2,274 participants. Overall, we found that the BIE was moderate-large in magnitude (Hedges' g = 0.75). Importantly, the inversion effect was larger for bodies than objects (b = 0.42); however, the inversion effect for faces was larger than for bodies (b = 0.34). We tested the role of discrimination dimension, stimulus type, face/head inclusion, stimulus sexualization, and sexualized stimulus sex as moderators of the BIE. We found that the BIE was moderated by discrimination dimension, stimulus type, stimulus sexualization, and sexualized stimulus sex. By synthesizing the existing literature, we provide a better theoretical understanding of how underlying visual processing mechanisms may differ for different types of social information (i.e., bodies vs. faces).
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Face , Reconhecimento Visual de Modelos , Teorema de Bayes , Humanos , Reconhecimento Psicológico , Percepção VisualRESUMO
Industrial hemp (IH) is defined as Cannabis sativa containing < 0.3% delta-9 tetrahydrocannabinol (THC) and was legalized in the 2018 Farm Bill. The impact of cannabinoids in IH fed to livestock, especially after repeat exposure, has not been thoroughly investigated. Sixteen male castrated Holstein cattle weighting (± SD) 447 ± 68 kg were enrolled onto the study. Cattle were allocated into two treatment groups either receiving IH (HEMP, n = 8) or a control (CNTL, n = 8). Cattle in the HEMP group were fed 25 g IH mixed in 200 g of grain once a day for 14 days to target a daily dose of 5.5 mg/kg of cannabidiolic acid (CBDA). Behavior was continuously monitored with accelerometers and blood samples were collected at predetermined time points for plasma cannabinoid, serum cortisol, serum haptoglobin, liver enzymes, serum amyloid A, and prostaglandin E2 concentrations. The HEMP group spent a mean 14.1 h/d (95% CI 13.6-14.6 h/d) lying compared to the 13.4 h/d (95% CI 12.9-13.8 h/d) for the CNTL cattle (P = 0.03). Cortisol concentrations in the HEMP group were lower than the CNTL group (P = 0.001). Cattle in the HEMP group demonstrated an 8.8% reduction in prostaglandin E2 concentrations from baseline compared to a 10.2% increase from baseline observed in the CNTL group. No differences for haptoglobin or serum amyloid A were observed. These results suggest that feeding IH with a high CBDA content for 14 days increases lying behavior and decreases biomarkers of stress and inflammation in cattle.
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Canabinoides , Cannabis , Animais , Biomarcadores , Bovinos , Haptoglobinas , Hidrocortisona , Inflamação , Masculino , Prostaglandinas , Proteína Amiloide A SéricaRESUMO
One of the most used methods to examine sources of heterogeneity in meta-analyses is the so-called 'subgroup analysis'. In a subgroup analysis, the included studies are divided into two or more subgroups, and it is tested whether the pooled effect sizes found in these subgroups differ significantly from each other. Subgroup analyses can be considered as a core component of most published meta-analyses. One important problem of subgroup analyses is the lack of statistical power to find significant differences between subgroups. In this paper, we explore the power problems of subgroup analyses in more detail, using 'metapower', a recently developed statistical package in R to examine power in meta-analyses, including subgroup analyses. We show that subgroup analyses require many more included studies in a meta-analysis than are needed for the main analyses. We work out an example of an 'average' meta-analysis, in which a subgroup analysis requires 3-4 times the number of studies that are needed for the main analysis to have sufficient power. This number of studies increases exponentially with decreasing effect sizes and when the studies are not evenly divided over the subgroups. Higher heterogeneity also requires increasing numbers of studies. We conclude that subgroup analyses remain an important method to examine potential sources of heterogeneity in meta-analyses, but that meta-analysts should keep in mind that power is very low for most subgroup analyses. As in any statistical evaluation, researchers should not rely on a test and p-value to interpret results, but should compare the confidence intervals and interpret results carefully.
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Metanálise como Assunto , Projetos de Pesquisa , HumanosRESUMO
The ability to recognize an individual face is essential to human social interaction. Even subtle errors in this process can have huge implications for the way we relate to social partners. Because autism spectrum disorder (ASD) is characterized by deficits in social interaction, researchers have theorized about the potential role of atypical face identity processing to the symptom profile of ASD for more than 40 years. We conducted an empirical meta-analysis of this large literature to determine whether and to what extent face identity processing is atypical in ASD compared to typically developing (TD) individuals. We also tested the hypotheses that the deficit is selective to face identity recognition, not perception, and that methodological variation across studies moderates the magnitude of the estimated deficit. We identified 112 studies (5,390 participants) that generated 172 effect sizes from both recognition (k = 119) and discrimination (k = 53) paradigms. We used state-of-the-art approaches for assessing the validity and robustness of the analyses. We found comparable and large deficits in ASD for both face identity recognition (Hedge's g = -0.86) and discrimination (Hedge's g = -0.82). This means that the score of an average ASD individual is nearly 1 SD below the average TD individual on tasks assessing both aspects of face identity processing. These deficits generalize across age groups, sex, IQ scores, and task paradigms. These findings suggest that deficits in face identity processing may represent a core deficit in ASD. (PsycInfo Database Record (c) 2021 APA, all rights reserved).
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Transtorno do Espectro Autista/psicologia , Discriminação Psicológica , Reconhecimento Facial , Reconhecimento Psicológico , Humanos , Projetos de PesquisaRESUMO
Human social interaction involves a complex, dynamic exchange of verbal and non-verbal information. Over the last decade, eye-tracking technology has afforded unique insight into the way eye gaze information, including both holding gaze and shifting gaze, organizes live human interactions. For example, while playing a social game together, speakers end their turn by directing gaze at the listener, who begins to speak with averted gaze (Ho et al., 2015). These findings reflect how eye gaze can be used to signal important turn-taking transitions in social interactions. Deficits in conversational turn-taking is a core feature of autism spectrum disorders. Individuals on the autism spectrum also have notable difficulties processing eye gaze information (Griffin & Scherf, 2020). A central hypothesis in the literature is that the difficulties in processing eye gaze information are foundational to the social communication deficits that make social interactions so challenging for individuals on the autism spectrum. Although eye-tracking technology has been used extensively to assess the way individuals on the spectrum attend to stimuli presented on computer screens (for review see Papagiannopoulou et al., 2014), it has rarely been used to evaluate the critical question regarding whether and how autistic individuals process non-verbal social cues from their partners during live social interactions. Here, we review this emerging literature with a focus on characterizing the experimental paradigms and eye-tracking procedures to understand the scope (and limitations) of research questions and findings. We discuss the theoretical implications of the findings from this review and provide recommendations for future work that will be essential to understand whether and how fundamental difficulties in perceiving and processing information about eye gaze cues interfere with social communication skills in autism.
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Background: Perceiving and interpreting eye gaze cues is foundational for social cognition and social interactions because it involves the ability to use eye gaze direction to predict the actions and intentions of others. Autism is a disability that impacts social interactions. A diagnostic symptom of autism is difficulty understanding eye gaze cues as social signals. This deficit has long-term consequences for understanding goal-directed behavior, language learning, and social communication. We hypothesize that targeted intervention methods designed to improve sensitivity to eye gaze cues may begin to treat core symptoms of autism and potentially alter multiple aspects of social functioning. Social Games for Autistic Adolescents (SAGA) is a serious computer game intervention designed to improve sensitivity to eye gaze cues. Serious games improve targeted skills with the goal of enhancing real life outcomes. In SAGA, participants progress through a narrative storyline and interact with animated characters. In so doing, they implicitly discover that eye gaze cues are useful for guiding their own goal-directed behavior to solve problems in the game. Methods: We evaluated the feasibility and effectiveness of SAGA in a hybrid phase 1/2, randomized controlled trial. Forty adolescents on the autism spectrum were randomized to either the treatment or standard care control group. Adolescents in the treatment group were asked to play SAGA for 30-minute sessions at home 3 times a week over 10 weeks. Results: A group × time interaction revealed that the treatment group developed increasing sensitivity to human eye gaze cues, whereas the standard care group did not. Participants who experienced a sufficient dose of gameplay showed larger treatment-related improvements. Critically, increases in sensitivity to human eye gaze cues were associated with improvements in social skills. Conclusions: This accessible, scalable, and affordable intervention shows promise as an effective tool for improving the ability to interpret and understand eye gaze cues and social skills in adolescents on the autism spectrum.
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BACKGROUND: Shifts in eye gaze communicate social information that allows people to respond to another's behavior, interpret motivations driving behavior, and anticipate subsequent behavior. Understanding the social communicative nature of gaze shifts requires the ability to link eye movements and mental state information about objects in the world. Autism spectrum disorder (ASD) is characterized by atypical sensitivity to eye gaze cues, which impacts social communication and relationships. We evaluated whether reduced visual attention to faces explains this difficulty in ASD. METHODS: We employed eye-tracking technology to measure visual attention to faces and gazed-at objects in a 4-alternative forced choice paradigm in adolescents with ASD and typically developing (TD) adolescents. Participants determined the target object that an actor was looking at in ecologically rich scenes. We controlled for group differences in task engagement and data quality. RESULTS: In the Gaze Following task, adolescents with ASD were relatively impaired (Cohen's d = 0.63) in the ability to identify the target object. In contrast to predictions, both groups exhibited comparable fixation durations to faces and target objects. Among both groups, individuals who looked longer at the target objects, but not faces, performed better in the task. Finally, among the ASD group, parent SSIS-Social Skills ratings were positively associated with performance on the Gaze Following task. In the Gaze Perception task, there was a similar pattern of results, which provides internal replication of the findings that visual attention to faces is not related to difficulty interpreting eye gaze cues. Together, these findings indicate that adolescents with ASD are capable of following gaze, but have difficulty linking gaze shifts with mental state information. LIMITATIONS: Additional work is necessary to determine whether these findings generalize to individuals across the full autism spectrum. New paradigms that manipulate component processes of eye gaze processing need to be tested to confirm these interpretations. CONCLUSIONS: Reduced visual attention to faces does not appear to contribute to atypical processing of eye gaze cues among adolescents with ASD. Instead, the difficulty for individuals with ASD is related to understanding the social communicative aspects of eye gaze information, which may not be extracted from visual cues alone.
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Atenção/fisiologia , Transtorno do Espectro Autista/fisiopatologia , Sinais (Psicologia) , Fixação Ocular/fisiologia , Percepção Visual/fisiologia , Adolescente , Comportamento , Face , Feminino , Humanos , Masculino , Estimulação LuminosaRESUMO
In this work, four varieties of hemp biomasses (Helena, SS Beta, Tygra, and Elleta Campana) pretreated with liquid hot water (LHW), H2SO4, and NaOH were investigated for ethanol production. Physicochemical and morphological properties of the pretreated hemp biomass were characterized. LHW achieved high glucan (85-98%) and xylan (67-71%) recoveries. H2SO4 induced significant glucan decomposition (5.9-10.6 g/L) and inhibitor formation (4.5-7.4 g/L of HMF and 2.8-4.5 g/L of furfural) in resulting slurries. Both LHW and H2SO4 pretreatments resulted in low glucose and ethanol yields due to recondensed lignin units. NaOH pretreatment achieved high glucose and ethanol yields due to efficient lignin removal (58.6-75.3%). There was no significant variation in ethanol yield among the four hemp varieties pretreated by NaOH. H2SO4 and NaOH pretreated biomasses showed apparent terraced-field structures and microporous protuberances. Changes in crystallinity indexes and intensities of FTIR peaks were consistent with enhanced cellulose and decreased amorphous hemicellulose.
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Álcalis , Cannabis , Biomassa , Hidrólise , Lignina , ÁguaRESUMO
In this study, the relationships between ethanol yield/concentration and solid loading (6-21%) were investigated to enhance ethanol titer and avoid a random choice of solid loading for simultaneous saccharification and fermentation (SSF). Alkali-pretreated hemp biomass was used for SSF in four scenarios including Case I: 30 filter paper unit (FPU)-cellulase and 140 fungal xylanase unit (FXU)-hemicellulase/g-solid; Case II: 40 FPU-cellulase and 140 FXU-hemicellulase/g-solid; Case III: 30 FPU-cellulase and 140 FXU-hemicellulase/g-solid with 1% Tween80; and Case IV: 30 FPU-cellulase and 140 FXU-hemicellulase/g-solid with particle size reduction (<0.2 mm). Results showed that bioethanol yield and concentration had a negative linear (R 2 = 0.76-0.93) and quadratic (R 2 = 0.96-0.99) correlation with solid loading (6-21%), respectively. As compared to Case I and previous studies, an enhancement in ethanol yield and concentration through increasing cellulase dose (Case II) and adding Tween 80 (Case III) was overestimated, whereas particle size reduction (Case IV) extended the "solid effect", evidenced by the highest ethanol concentration (77 g/L) achieved from SSF at the focus point of a quadratic model. An interpretation of the relationship between ethanol yield/concentration and solid loading not only avoids a blind selection of solid loading for SSF but also reduces extra enzymes and water consumption.
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OBJECTIVES: The ability to process information about eye gaze and its use for nonverbal communication is foundational to human social interactions. We developed and validated a database of stimuli that are optimized to investigate the perception and referential understanding of shifts in eye gaze. METHODS: The 245 Gaze Perception stimuli are digital photographs that test the ability to estimate and interpret eye gaze trajectory. The 82 Gaze Following stimuli are digital videos that measure the ability to follow and interpret eye gaze shifts online. Both stimuli were designed for a 4-alternative forced choice paradigm (4AFC) in which the participant identifies the gazed-at object. RESULTS: Each stimulus was validated by independent raters and only included if the endorsement of the correct item was ≥75%. Finally, we provided timestamps for 19 40-second video segments from adolescent-oriented entertainment movies that are matched on several factors. These segments involve social interactions with eye gaze shifts and can be used to measure visual social attention. CONCLUSIONS: This database will be an excellent resource for researchers interested in studying the developmental, behavioral, and/or neural mechanisms supporting the perception and interpretation of eye gaze cues.