PRISM :: Browsing by Author "Graham, Susan A."

Browsing by Author "Graham, Susan A."

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Open Access
14- to 16-Month-Olds Attend to Distinct Labels in an Inductive Reasoning Task
(Frontiers Media S.A., 2017-01) Switzer, Jessica L.; Graham, Susan A.
We examined how naming objects with unique labels influenced infants' reasoning about the non-obvious properties of novel objects. Seventy 14- to 16-month-olds participated in an imitation-based inductive inference task during which they were presented with target objects possessing a non-obvious sound property, followed by test objects that varied in shape similarity in comparison to the target. Infants were assigned to one of two groups: a No Label group in which objects were introduced with a general attentional phrase (i.e., "Look at this one") and a Distinct Label group in which target and test objects were labeled with two distinct count nouns (i.e., fep vs. wug). Infants in the Distinct Label group performed significantly fewer target actions on the high-similarity objects than infants in the No Label group but did not differ in performance of actions on the low-similarity object. Within the Distinct Label group, performance on the inductive inference task was related to age, but not to working memory, inhibitory control, or vocabulary. Within the No Label condition, performance on the inductive inference task was related to a measure of inhibitory control. Our findings suggest that between 14- and 16-months, infants begin to use labels to carve out distinct categories, even when objects are highly perceptually similar.
Open Access
The AMBIANCE-brief: An observational assessment tool of disruptive caregiving for use in applied settings with families at high social risk
(2019-08-27) Cooke, Jessica Elizabeth; Madigan, Sheri L.; Graham, Susan A.; Noel, Melanie; Benzies, Karen Marie
Background: A community-identified need has emerged for a well-validated indicator of caregiving difficulties for use in practice settings. Thus, a brief form of the Atypical Maternal Behavior Instrument for Assessment and Classification System (AMBIANCE) was developed for use as a screening instrument. Prior to its dissemination in practice settings, further evidence of the feasibility and validity of the AMBIANCE-Brief must be established. Objectives: The current study aims to: assess feasibility of coding disrupted caregiving in real-time; establish the convergent validity of the AMBIANCE-Brief with the full AMBIANCE, as well as its postdictive validity in relation to maternal unresolved states of mind, and its concurrent validity with infant attachment disorganization; examine if the relation between maternal unresolved states of mind and infant attachment disorganization is mediated by maternal disrupted caregiving as assessed by the AMBIANCE-Brief. Method: Adolescent mothers and their infants (N = 69 dyads) participated when infants were 6 and 12 months of age. At 6 months of age, mothers completed the Adult Attachment Interview (AAI). Dyads completed the Strange Situation Procedure (SSP), as well as play sessions with toys and without toys when infants were 12 months of age. Maternal disrupted caregiving was coded from the play sessions using the full AMBIANCE and AMBIANCE-Brief. Results: The AMBIANCE-Brief demonstrated strong convergent validity with the full AMBIANCE, postdictive validity with maternal unresolved states of mind, and concurrent validity with infant attachment disorganization in both play sessions. However, maternal disrupted caregiving, as assessed by the AMBIANCE-Brief, did not significantly mediate the association between maternal unresolved states of mind and infant attachment disorganization. Conclusions: The current work represents an initial step in the development of shorter protocols which are more efficient for practitioners to use in practice settings. Future studies are needed to establish evidence of validity and feasibility of the AMBIANCE-Brief in community agencies.
Open Access
Audiovisual integration in 4-and 5-year-old children: Behavioural and neural responses
(2020-01) Beatch, Jacqueline Ann; Curtin, Suzanne; Protzner, Andrea; Graham, Susan A.; Bray, Signe L.; Yeung, H. Henny
Dynamic information in the environment often stems from multiple modalities, such as auditory and visual (audiovisual; AV). The ability to detect and integrate AV information draws attention to salient information, allows for efficient processing, and helps individuals learn sound-object associations, which can impact language development. In this dissertation, I explore stimulus characteristics that affect how AV information is integrated and processed in 4-and 5-year-olds and the relation to their receptive language (RL). In Chapter 2, I examine whether 4-and 5-year-old’s integrate AV stimuli resulting in faster and more accurately responses to matched AV compared to mismatched AV and unisensory stimuli. This was the case. I further hypothesized that responses to matching AV stimuli would predict children’s RL, which was not supported. Moreover, I hypothesized that children’s executive functioning would predict responses to mismatched stimuli, which was the case. Thus, children integrate AV information and their broader skills impact how quickly and effectively they respond to information in their environment. In Chapter 3, I use EEG to investigate 4-and 5-year-old’s processing of AV synchronous/ asynchronous human/ monkey videos. I found increased processing for mouth movements paired with vocalizations (i.e., synchronous), compared to mouth movements alone, and for auditory human, compared to monkey, vocalizations. Synchrony and species affected AV processing differently based on the modality (i.e., auditory or visual) being examined. In Chapter 4, I expand on the work in Chapter 3 to examine whether children’s neural responses are related to their RL. Here I found that 4-year-old’s processing of visual synchronous and 666ms asynchronous stimuli were related to their RL. However, no significant relation was found for the 5-year-olds. For both ages, reduced processing for auditory stimuli, iii regardless of synchrony and species, was related to higher RL. This may suggest that children who reduce processing to nonsense vocalization have more cognitive resources to process meaningful information and had higher RL. I conclude by discussing the importance of understanding the nuances of AV integration and processing in early childhood as these foundational skills are related to their development. This provides a base for future research to explore AV integration in atypical development.
Open Access
Children’s Attention to Emotional Prosody: Pragmatic Adjustment in Response to Speaker Conventionality
(2018-11-19) Thacker, Justine Marie; Graham, Susan A.; Chambers, Craig G.; Pexman, Penny M.; Sedivy, Julie
In this dissertation, I examined whether children will pragmatically adjust their expectations about a speaker’s referential intent, depending on whether the speaker provided conventional or unconventional descriptions. In Chapter 2, 4- and 5-year-old children were introduced to one of two possible speakers: (1) conventional speaker who demonstrated congruent use of linguistic and affective cues; or (2) unconventional speaker who demonstrated incongruent use of these cues and who was described as saying “things in a strange way”. Test trials consisted of displays containing pairs of objects that belonged to the same category, but that differed in terms of their likelihood of association with negative or positive emotional prosody (broken doll/intact doll), accompanied by referentially ambiguous instructions (“Look at the doll”) spoken in either a positive- or negative-sounding voice. Results indicated that children in the conventional speaker condition directed a greater proportion of looks to the negative object during negative emotional prosody trials, compared to positive emotional prosody trials. In contrast, there was no effect of emotional prosody in the unconventional speaker condition. In Chapter 3, I further examined the extent to which children will suspend their use of emotional prosody for an unconventional speaker. In Experiment 2, the experimenter's description of the speaker's trait was replaced with a neutral statement, but examples of the speaker’s incongruent use of linguistic and affective cues were retained. Again, children suspended their use of emotional prosody as a cue to referential intent. In Experiments 3 and 4, children were introduced to two different versions of an unconventional speaker that varied in terms of how related their unconventionality was to their use of emotional prosody. Results demonstrated that speaker unconventionality that was closely related to emotional expression had an effect on children’s use of emotional prosody. However, when speaker unconventionality was unrelated to emotional expression, 5-year-old, but not 4-year-old, children returned to their original pattern of looking whereby the used emotional prosody to resolve referential intent. This selectivity in response to different speakers provides compelling evidence that social-pragmatic reasoning underlies preschoolers’ interpretation of emotional prosody. Chapter 4 summarizes and explores the aforementioned findings in greater detail.
Open Access
Co-constructing the Past: Examining Mother- and Father-Child Narratives About Past Events Involving Pain versus Sadness
(2019-08-26) Pavlova, Maria; Noel, Melanie; Graham, Susan A.; Madigan, Sheri L.; McMorris, Carly A.
Background. Parent-child reminiscing about past events creates an influential sociolinguistic context within which children’s development occurs. Parents differ dramatically in their reminiscing styles, whereas some parents are highly elaborative (i.e., they use open-ended detailed questions) and focus on talking about emotions, other parents are repetitive and emphasize factual information. Elaborative reminiscing has been linked to more optimal developmental outcomes. No studies have examined how parent-children reminiscing about past pain compares to other stressful experiences (i.e., sadness, fear), and how parent-children reminiscing about past pain might be linked to children’s socio-emotional skills. This study was the first to examine the association between parent-child reminiscing about past pain and children’s prosocial acts to pain-related distress in others as well as overall children’s socio-emotional functioning. Methods. One hundred and sixteen 4-year old children (54% girls) and their parents (49% mothers) completed a structured narrative elicitation task wherein they reminisced about a unique past event involving pain, fear, and sadness. Children then witnessed a confederate pretending to be in pain (i.e., hurt fingers and a knee). Children’s prosocial responses and parent-child narratives about past pain were coded using established coding schemes based on the developmental psychology literature. Results. Parent-children narratives about pain were characterized by less emotion-laden and more coping and pain-related words as compared to sadness or fearful narratives. Parents, who used open-ended questions, provided new information, and talked about emotions and coping when talking about past events involving pain, had children who exhibited more prosocial acts and concern in response to other’s pain and had higher parent-reported levels of empathy. Discussion. Parent-children reminiscing about past pain differs from reminiscing about other types of distressing events (e.g., involving sadness or fear) and is linked to children’s socio-emotional skills. This highlights a possibility of differential socialization of pain. Parent-child reminiscing is amenable to intervention and offers a promising avenue for pediatric pain management interventions.
Open Access
Cohort Profile: The All Our Babies pregnancy cohort (AOB)
(Oxford University Press, 2017-01) Tough, Suzanne C.; McDonald, Sheila W.; Collisson, Beverly Anne; Graham, Susan A.; Kehler, Heather L.; Kingston, Dawn E.; Benzies, Karen Marie
Open Access
Deriving meaning from print: The role of sensorimotor information and context in semantic processing
(2019-01-07) Doyle, Alison Weyman; Pexman, Penny M.; Protzner, Andrea B.; Bodner, Glen E.; Graham, Susan A.; Taler, Vanessa; O'Brien, Mary Grantham
The process by which meaning is derived from words has been described by a number of different theories. Most recently, hybrid theories have claimed that both lexical and perceptual information are involved in deriving meaning from words, and that the relative contributions of each are dependent on context (Zwaan, 2014). In Chapter 2, predictions derived from these theories were tested by examining semantic richness effects in a semantic decision task (SDT) across two conditions. EEG was recorded while participants categorized words rated high or low for body-object interaction (BOI), a sensorimotor semantic richness dimension that measures ease of bodily interaction with the word’s referent (Siakaluk, et al., 2008a). In one condition participants decided whether each word was an entity or non-entity and in the other condition participants decided whether each word was an action or non-action. The behavioural results from Experiment 1 replicated previous findings (Tousignant & Pexman, 2012): a BOI effect (faster responses for high BOI words than for low BOI words) was observed in the entity/non-entity condition only. The results from Experiment 2 showed a significant difference in mean amplitude and rectified area of the P2 component between high and low BOI words in the entity condition only. These results indicate that sensorimotor information was recruited differently in each condition, suggesting that the recruitment of semantic information is a dynamic process, dependent on task demands. Although the BOI dimension has proven useful for investigating the role of sensorimotor information in lexical-semantic processing it is a fairly coarse measure of sensorimotor experience with words’ referents. The research reported in Chapter 4 addressed this issue by collecting ratings for 621 words on seven semantic dimensions in order to investigate which attributes are most strongly related to BOI ratings and to lexical–semantic processing. The results showed that the motor dimensions of graspability, ease of pantomime, and number of actions were all related to BOI, and that these dimensions together explained more variance in semantic processing than did the BOI ratings alone. These findings support hybrid theories of semantic processing, and provide additional insights about the nature of sensorimotor semantic processing.
Open Access
Early Language Abilities and the Underlying Neural Functional Reading Network in Preschoolers
(2018-06-25) Benischek, Alina Marie; Lebel, Catherine A.; Dewey, Deborah; Bray, Signe L.; Graham, Susan A.
Early childhood is a critical time for language development. Language impairments that go untreated in the early years can result in decreased academic achievement and future mental health concerns. Despite the importance of early language development, very little research has focused on the functional brain systems supporting language in typically developing young children. We investigated relationships between age, language abilities, and the brain’s functional connectivity (FC) patterns seeded from brain areas associated with reading. The study included 50 healthy children aged 2.9-5.6 years (3.8 ± 0.6 years, 21f/29m) who completed a language assessment (NEPSY-II Phonological Processing and Speeded Naming) and underwent functional MRI (magnetic resonance imaging) scanning while watching a movie. Phonological Processing scores positively correlated with FC between the left angular gyrus and contralateral sensorimotor cortices, as well as between the right angular gyrus and the left supramarginal gyrus. Speeded Naming scores positively correlated with FC between the left inferior frontal gyrus, pars triangularis and the left fusiform gyrus, extending to the posterior region of the middle/inferior temporal gyrus and negatively correlated with the precuneus of the default mode network. Despite these variations in the FC patterns associated with speeded naming and phonological processing, both language measures positively correlated with FC between the ROI and the angular gyrus, supramarginal gyrus, and precentral gyrus. Age positively correlated with FC between regions within the ventral language pathway, including the inferior frontal gyrus and middle/inferior temporal gyrus and negatively correlated with FC between ipsilateral language regions and contralateral visual areas within the occipital cortex. The results demonstrate that better language abilities in young children are associated with stronger functional connections between brain regions within the language network identified in older children and adults who can perform more complex language processes.
Open Access
Examining the Effect of Category-Training on 11-Month-Olds’ Property Generalizations
(2018-08-08) Zepeda, Michelle Stephanie; Graham, Susan A.; Noel, Melanie; Curtin, Suzanne; Drefs, Michelle A.
The ability to form category-property links allows infants to generalize a property from one category member to another. In the present studies, I examined whether orienting infants to the demands of the task, through categorization training, would facilitate 11-month-old infants’ property extensions when familiarized with a single exemplar of a novel animal category. In Experiment 1, 11-month-olds (N = 32) were trained with two familiar animal-sound pairings (i.e., dog-bark, cat-meow), and tested on their learning and generalization of novel animal-sound associations. Across two conditions, Experiment 2 familiarized 11-month-olds (N = 58) to one familiar (i.e., dog-bark) and one novel animal-sound pairing. Conditions differed in their presentation of familiarization trials (i.e., random or blocked). Infants were also tested on their learning and extension of the animal-sound associations. In both studies, infants did not demonstrate learning of the original animal sound pairing, nor generalization of the sound property to new members of the animal categories. These results indicate that categorization training did not facilitate 11-month-olds’ ability to learn or generalize a novel animal-sound association, when familiarized with a single exemplar.
Open Access
Exploring Trajectories of Language Development in Children with Autism Spectrum Disorder Across Multiple Measures
(2020-09-06) Hart, Chelsie Miko; Curtin, Suzanne; Graham, Susan A.; McMorris, Carly A.; McCrimmon, Adam W.
Autism Spectrum Disorder (ASD) is a developmental disability that affects the cognitive development of up to 1 in 59 children globally, particularly in language abilities (Baio et al., 2018). With increasing prevalence and research showing the benefits of early intervention, there is value in diagnosing ASD as soon as possible. However, ASD is typically not diagnosed until after age two, when many developmental milestones should have passed and parental concerns may have already risen (Falck-Ytter, 2012; Landa et al., 2013). Research must include measures from earlier in childhood to improve diagnosis methods and capture a full picture of this disability. This study examined how different language measures capture the range of expressive and receptive language vocabulary in children from 6 to 36 months of age; longitudinally comparing children eventually diagnosed with ASD to typically developing peers. Children were assessed repeatedly using the Mullen Scales of Early Learning (MSEL; Mullen, 1995), MacArthur-Bates Communicative Development Inventory (CDI; Fenson et al., 2007), and One-Word Picture Vocabulary Tests (PVT; Martin & Brownell, 2011a; 2011b). Results from mixed regression analysis showed that most measures could distinguish children with ASD as a group by 24 months. However, the Expressive PVT did not distinguish the ASD group from typically developing groups, despite being correlated with all other measures. Further examination of individual trajectories for children with ASD showed high, but inconsistent heterogeneity from scale to scale. This combination of varying group and individual differences suggests that these common assessments may not capture children’s abilities in the same way or to the same extent. Thus, this study supports that, to accurately observe the wide range developmental trajectories seen in ASD, professionals must consider the characteristics of the tools being used. Capturing this developmental variability is vital for creating effective targeted early interventions.
Open Access
Five-Year-Olds' and Adults' Use of Paralinguistic Cues to Overcome Referential Uncertainty
(Frontiers Media S.A., 2018-01) Thacker, Justine Marie; Chambers, Craig G.; Graham, Susan A.
An eye-tracking methodology was used to explore adults' and children's use of two utterance-based cues to overcome referential uncertainty in real time. Participants were first introduced to two characters with distinct color preferences. These characters then produced fluent ("Look! Look at the blicket.") or disfluent ("Look! Look at thee, uh, blicket.") instructions referring to novel objects in a display containing both talker-preferred and talker-dispreferred colored items. Adults (Expt 1, n = 24) directed a greater proportion of looks to talker-preferred objects during the initial portion of the utterance ("Look! Look at…"), reflecting the use of indexical cues for talker identity. However, they immediately reduced consideration of an object bearing the talker's preferred color when the talker was disfluent, suggesting they infer disfluency would be more likely as a talker describes dispreferred objects. Like adults, 5-year-olds (Expt 2, n = 27) directed more attention to talker-preferred objects during the initial portion of the utterance. Children's initial predictions, however, were not modulated when disfluency was encountered. Together, these results demonstrate that adults, but not 5-year-olds, can act on information from two talker-produced cues within an utterance, talker preference, and speech disfluencies, to establish reference.
Open Access
How spatial is spatial language? Investigating the relationship between spatial cognition and abstract language processing
(2020-06-23) Hannah, Jaimy Anne; Iaria, Giuseppe; Pexman, Penny M.; Curtin, Suzanne; Graham, Susan A.
The present study aimed to explore the relationship between spatially grounded language and spatial cognition. According to embodied cognition, sensitivity to spatial grounding should be related to experience with spatial cognition. Participants completed three language tasks assessing their sensitivity to spatial grounding and three spatial tasks assessing different facets of spatial cognition. These language tasks were derived from previous studies that showed spatial grounding effects. Only of these effects was replicated; the presence of a mental number line. From each of the language tasks, a spatial grounding sensitivity score was calculated based on the difference in reaction times between incongruent and congruent trials. These sensitivity scores were then correlated to performance on the spatial tasks. The results showed almost no significant correlations between the language tasks and spatial tasks, even when looking at those individuals who were most highly sensitive to spatial grounding. Overall the results of this study do not support an embodied view of cognition.
Open Access
Infants' categorization of novel objects with more or less obvious features
(Elsevier, 2006-02) Welder, Andrea N.; Graham, Susan A.
In five experiments, 14- to 15-month-old infants' categorization of objects on the basis of more or less obvious features was investigated. Using an object examining paradigm, a total of 200 infants were familiarized with novel objects that shared either more obvious features (i.e., easily visible) or less obvious features (i.e., accessible by lifting a flap), followed by an in-category object and an out-of-category object. When only perceptual information was available, infants formed a category on the basis of the more obvious features but not on the basis of the less obvious features (Experiments 1 and 3). When infants were provided with animacy cues and/or object names, they formed categories on the basis of either more or less obvious features (Experiments 2, 4, and 5). The results of these studies delineate the role of animacy cues and object names in establishing categories on the basis of less obvious features.
Open Access
Neuroplasticity in Visual Word Recognition: An Exploration of Learning-Related Behavioural and Neural Changes
(2020-06-17) Cnudde, Kelsey Dawn; Protzner, Andrea; Pexman, Penny M.; Bray, Signe L.; Graham, Susan A.; Wilcox, Gabrielle
Visual word recognition is a cognitive process that remains relatively stable throughout adulthood. Despite this stability, recent research suggests that the system involved is malleable, by showing evidence of behavioural change after lexical decision task (LDT) practice, and of neural differences between-subjects during LDT performance. However, these studies leave the question unanswered as to whether neural change can occur within the visual word recognition system, which would suggest plasticity. We therefore investigated whether neural change accompanies the behavioural change previously found with LDT practice. If found, these neural changes could be due to processes associated with learning, where performance that is initially unskilled and effortful becomes skilled and efficient, and supported by a more specific, honed, and optimized task network. We replicated the British Lexicon Project (BLP), in which participants completed several days of LDT learning. We additionally recorded EEG at three time points to track neural change during LDT learning, and assessed event-related potentials and brain signal complexity. We found response time decreased during LDT learning, replicating the BLP. We also found neural change occurred through N170, P200, N400, and LPC amplitude effects, suggesting alterations to both the general cognitive and specific lexical processes involved in LDT performance. There was also widespread complexity decreases alongside localized increases, suggesting that with learning, LDT processing became more automatic with specific increases in processing flexibility. These findings suggest that the visual word recognition system is dynamic, flexible, and capable of undergoing plastic changes to support more efficient and automatic task performance.
Open Access
A New Perspective on Children's Communicative Perspective Taking: When and How Do Children Use Perspective Inferences to Inform Their Comprehension of Spoken Language?
(Society for Research In Child Development, 2015-01) San Juan, Valerie; Khu, Melanie; Graham, Susan A.
Successful communication often requires a listener to reason about a speaker’s perspective to make inferences about communicative intent. Although children can use perspective reasoning to influence their interpretation of spoken utterances, when and how children integrate perspective reasoning with language comprehension remain unclear. These questions are central to theoretical debates in language processing and have led to competing accounts of communicative perspective taking: early versus late integration. In this article, we examine how developmental evidence addresses the predictions of each account. Specifically, we review evidence to determine whether children can rapidly integrate perspective inferences when processing spoken language while central abilities (i.e., executive function and theory of mind) are still emerging.
Open Access
One is Not Enough: Multiple Exemplars Facilitate Infants' Generalizations of Novel Properties
(Wiley-Blackwell, 2015-01) Vukatana, Ena; Graham, Susan A.; Curtin, Suzanne; Zepeda, Michelle S.
Across three experiments, we examined 9- and 11-month-olds’ mappings of novel sound properties to novel animal categories. Infants were familiarized with novel animal–novel sound pairings (e.g., Animal A [red]–Sound 1) and then tested on: (1) their acquisition of the original pairing and (2) their gen- eralization of the sound property to a new member of a familiarized cate- gory (e.g., Animal A [blue]–Sound 1). When familiarized with a single exemplar of a category, 11-month-olds showed no evidence of acquiring or generalizing the animal–sound pairings. In contrast, 11-month-olds learnt the original animal–sound mappings and generalized the sound property to a novel member of that category when familiarized with multiple exemplars of a category. Finally, when familiarized with multiple exemplars, 9-month- old infants learnt the original animal–sound pairing, but did not extend the novel sound property. The results of these experiments provide evidence for developmental differences in the facilitative role of multiple exemplars in promoting the learning and generalization of information.
Embargo
Preschoolers' Attention to Emotional Prosody as a Function of Speaker Conventionality
(2020-08-24) Wieczorek, Karolina Marta; Graham, Susan A.; Curtin, Suzanne; Noel, Melanie; Skordos, Dimitrios
Emotional prosody is a paralinguistic cue that can provide information about a speaker’s emotional state. The current study examined preschoolers’ pragmatic adaptation in the use of emotional prosody. Specifically, the aims were: 1) to examine 4- and 5-year-olds’ use of emotional prosody to resolve ambiguity as a function of speaker conventionality and 2) to assess whether individual differences in cognitive and social skills contribute to this ability. Using an eye-tracking paradigm, children were presented with a speaker who used emotional prosody in both a conventional and unconventional manner within the same interaction. Following the speaker’s demonstration of conventionality, children’s use of emotional prosody in resolving ambiguity was examined using eye-gaze (i.e., implicit) and pointing (i.e., explicit) measures. Children also completed executive functioning measures (i.e., the NIH Toolbox Early Childhood Cognition Battery) and parents completed a social skills questionnaire (i.e., the Social Skills Improvement System). The findings indicated that children’s implicit processing of emotional prosody was influenced by negative emotional prosody, while children’s explicit processing of emotional prosody was influenced by the speaker’s initial conventionality. Children were flexible in response to the speaker’s initial conventionality but did not adapt their inferences when the speaker changed. This work adds to the literature supporting the use of socio-cognitive learning mechanisms and aids in clarifying the pragmatic thresholds that 4- and 5-year-olds apply in their in-the-moment reasoning about a speaker’s communicative intent.
Embargo
Preschoolers’ Attention to Social Allegiances When Identifying Social Category Membership
(2019-02-04) Switzer, Jessica L.; Graham, Susan A.; Curtin, Suzanne; Madigan, Sheri L.
One way that children organize social categories is through an understanding that social categories mark individuals who are socially obligated to one another (Rhodes, 2012a). In this dissertation, I investigated: (1) whether 4- and 5-year-old children infer the social category membership of an individual based on observed relational interactions; (2) whether children use these social categories to guide inductive inferences about related category properties; and (3) whether children require rich linguistic cues to establish meaningful categories from which to make categorical inferences. In Chapter 2, I investigated children’s ability to categorize an individual on the basis of helpful and harmful behaviour directed from a novel social category member to an ambiguous individual whose category membership was not identified. I then asked whether children would generalize a category property to the newly identified member of the category. In Experiment 1, children identified the ambiguous character as belonging to the same category as the individual who helped them, but as belonging to a different social category as the individual who harmed them. Children did not extend the category property to the new member of the category. In Experiment 2, when the category properties were framed as mutually exclusive social conventions, children extended the property to newly identified members of the category. In Experiment 3, I sought to elucidate whether preschoolers require rich linguistic input to form meaningful social categories from which to make categorical inferences. Categories were described without category labels and marked only by spatial segregation and shared properties. Here, children did not identify social category membership on the basis or helpful or harmful behaviour, nor did they generalize category properties. In Chapter 3, I examined whether children infer social category membership on the basis of observed social interactions when categories were labeled with a familiar count-noun. Here, children categorized an ambiguous individual based on harmful, but not helpful, behaviour. The results highlight: (1) children’s ability to infer social category membership on the basis of social interactions; and (2) that children require category information made available via robust linguistic cues to prompt them to attend to social interactions.
Open Access
Reward Neurocircuitry in Autism Spectrum Disorder
(2018-09-14) Schuetze, Manuela; Bray, Signe L.; Kennedy, Dan; Graham, Susan A.; Borgland, Stephanie Laureen; Goodyear, Bradley G.; Dewey, Deborah
Autism spectrum disorder (ASD) is a common neurodevelopmental disorder with social impairments and restricted interests. Early behavioural interventions often focus on reinforcing desired behaviours (e.g., eye contact) and reducing atypical behaviours (e.g., echoing others' phrases). A recent framework suggests reward system dysfunction to be at the core of ASD symptoms. However, if the reward system is impaired in ASD, it is paradoxical that reward-based strategies are commonly used during interventions. The goal of this thesis was to investigate the reward neurocircuitry to explore whether reward system dysfunction contributes to the ASD phenotype. We conducted a literature review on physiological, behavioural, and neural responses to reinforcers to look for common atypical patterns across all domains. We then investigated structural changes in basal ganglia and the thalamus using advanced surface-based methodology. For this, we modelled effects of diagnosis, age, and their interaction on volume, shape, and surface area on T1-weighted anatomical images of 373 male participants with ASD and 384 typically developing (TD). Finally, we investigated neural responses in the context of learning using rewards that were tailored to participants’ unique interests. 27 adolescents with ASD and 31 TD adolescents performed a reinforcement learning task while we collected fMRI data. Participants had to learn which of two doors showed images of their personal interests. The literature review revealed no consistent pattern of atypical reward responses in ASD. Further, we found that subcortical regions did not differ in volume between individuals with and without ASD. However, we found localized structural changes in shape and surface area of the putamen, globus pallidus and thalamus. Some changes were modulated by age, IQ and symptom severity. Interestingly, when using personal interests as reinforcers during a learning task, we found intact learning performance and similar neural responses in the reward system between ASD and TD groups. Taken together, mixed findings from the literature review and subtle structural changes in subcortical regions of the reward system suggest a role of this neurocircuitry in the ASD phenotype. However, intact learning and typical neural responses towards individual interests suggest that the reward system is not generally impaired in ASD.
Open Access
The Role of Attentional Biases for Conspecific Vocalizations
(2018-04-30) Ference, Jennifer Diana; Curtin, Suzanne; Vouloumanos, Athena; Graham, Susan A.
A bias for speech over non-speech emerges at birth in typically developing (TD) infants and a preference for vocalizations generated from one’s own species (conspecific) emerges by 3 months. These biases and preferences may direct infants to relevant communicative information in their language learning environments, possibly predicting positive linguistic and social development. The first series of studies explored whether a bias for speech (over non-speech) at 6 and 9 months was predictive of language and social behaviors at 12 months. Whether a preference for conspecific vocalizations (over monkey calls) at 9 months was predictive of these same outcomes was also examined. Infants were biased toward speech over non-speech at 6 and 9 months, but preferred monkey calls over speech at 9 months. However, these listening patterns did not predict language or social developmental outcomes. Understanding these patterns of attention and how experimental procedures may influence preferences is important for advancing our understanding of the relationship between attention to speech and early development. The second series of studies reports findings from high-risk (HR) infant siblings of children diagnosed with Autism Spectrum Disorder (ASD), who participated in these same experiments. HR infants are known to have heterogeneous outcomes by age 3, with about half developing typically, while others present with atypical outcomes, including ASD. Given the hypothesized importance of attention to speech on later development, we explored whether HR infants as a group selectively attended to speech and whether such attention was predictive of early language and social behaviors. HR infants were biased toward speech at 6 months; however, by 9 months, they did not differentially attend to speech over non-speech or monkey calls overall. Despite this, increased attention to speech at 9 months predicted better language and fewer autism-like behaviors at 12 months. Therefore, increased attention to conspecifics may indicate typical outcomes for HR infants. Future directions include following both groups of infants to 3 years of age to explore whether selective attention to speech during the first year is predictive of much later developmental outcomes and/or diagnostic status.