Autism Spectrum Disorders (ASDs) are characterised by impairments in social interaction and communication, and restricted interests or repetitive behaviours. Autism traits are theorised to lie on a continuum throughout the general population, with individuals with a clinical diagnosis at one extreme. Those with high levels of autism traits in the general population have been found to display similar characteristics to those with ASD, but to a lesser extent. Differences in visual attention to social and non-social information are thought to contribute to the characteristic behaviours in autism. Whilst social attention may be diminished in ASD, ASD may also be associated with an increase in attention towards objects that are of circumscribed interest. The present thesis investigated visual attention to social and non-social objects in participants with ASD and those from the general population with high and low autism traits, to investigate whether differences in social and non-social visual attention relate to the autism spectrum. Dot probe, peripheral cueing, and eye tracking tasks were used to explore different elements of visual attention, including orienting and disengaging. Overall, social objects captured attention more than non-social objects, revealing the high salience of social information. Participants with high levels of autism traits and a diagnosis of ASD showed reduced social attention in the dot probe and eye tracking tasks, but not the peripheral cueing experiment. Across all experiments, there was no evidence to suggest that the autism spectrum was related to attentional biases towards objects related to circumscribed interests. However, other non-social stimuli appeared to capture attention to a greater extent across the spectrum. The differences in social attention in those with higher autism traits and ASD appeared greater when more stimuli were competing for attention, suggesting reduced social attention may involve interference from non-social stimuli in the visual field. This may indicate that attention is guided more by visual properties of the stimuli than their semantic meaning in the autism spectrum.

The purpose of this study was to examine whether infants' social attention, as well as their joint attention behaviors uniquely predicted emerging language abilities. This longitudinal study examined attention regulation skills, joint attention behaviors, infants' expressive/receptive language (current), emerging communication abilities at 16- and 17-month-old (time 1); expressive/receptive language (subsequent) at 18- 19-month-old (time 2). Infants' sustained attention was measured by their attention control to a central stimulus in the presence of a distracter competing for their attention. Dynamic human face (upright, inverted) and abstract display with their matched voice tracks were used to separately measure infants' attention regulation to different types of events. Infants' sustained attention was estimated by their latencies away from central stimuli to distracters, as well as their fixation duration and gaze count on central events and distracters. It was found that infants' latency away from the abstract figure toward the distracter was the only variable that significantly negatively predicted current expressive vocabulary. Initiating joint attention was observed to significantly predict infants' abilities in current receptive vocabulary. The emerging language communication ability predicted expressive vocabulary at two times. In addition, infants' fixation and count to the upright speaker's face and eyes contributed significant amount of variance in initiating joint attestation. The fixation and gaze count on the distracter in the upright condition significantly predicted infants' emerging language skills. / Ph. D.

We have a strong intuition that people's eyes are unique, socially informative stimuli. As such, it is reasonable to propose that humans have developed a fundamental tendency to preferentially attend to eyes in the environment. The empirical evidence to support this intuition is, however, remarkably thin. Over the course of eight chapters, the present thesis considers the area of social attention, and what special role (if any) the selection of eyes has in it. Chapters 2 and 3 demonstrate that when observers are shown complex natural scenes, they look at the eyes more frequently than any other region. This selection preference is enhanced when the social content and activity in the scene is high, and when the task is to report on the attentional states in the scene. Chapters 4 and 5 establish that the bias to select eyes extends to a variety of tasks, suggesting that it may be fundamental to human social attention. In addition, Chapter 5 shows that observers who are told that they will have to remember the scenes look more often at the eyes than observers who are unaware of the forthcoming memory test; moreover this difference between groups persists to scene recognition. Chapter 6 examines whether the preference for eyes can be explained by visual saliency. It cannot. Chapter 7 compares the selection of eyes to another socially communicative cue, the arrow. The results shed light on a recent controversy in the social attention field, and indicate again that there is a fundamental bias to select the eyes. Collectively the data suggest that for typically developing adults, eyes are rich, socially communicative stimuli that are preferentially attended to relative to other stimuli in the environment.

We have a strong intuition that people's eyes are unique, socially informative stimuli. As such, it is reasonable to propose that humans have developed a fundamental tendency to preferentially attend to eyes in the environment. The empirical evidence to support this intuition is, however, remarkably thin. Over the course of eight chapters, the present thesis considers the area of social attention, and what special role (if any) the selection of eyes has in it. Chapters 2 and 3 demonstrate that when observers are shown complex natural scenes, they look at the eyes more frequently than any other region. This selection preference is enhanced when the social content and activity in the scene is high, and when the task is to report on the attentional states in the scene. Chapters 4 and 5 establish that the bias to select eyes extends to a variety of tasks, suggesting that it may be fundamental to human social attention. In addition, Chapter 5 shows that observers who are told that they will have to remember the scenes look more often at the eyes than observers who are unaware of the forthcoming memory test; moreover this difference between groups persists to scene recognition. Chapter 6 examines whether the preference for eyes can be explained by visual saliency. It cannot. Chapter 7 compares the selection of eyes to another socially communicative cue, the arrow. The results shed light on a recent controversy in the social attention field, and indicate again that there is a fundamental bias to select the eyes. Collectively the data suggest that for typically developing adults, eyes are rich, socially communicative stimuli that are preferentially attended to relative to other stimuli in the environment.

We have a strong intuition that people's eyes are unique, socially informative stimuli. As such, it is reasonable to propose that humans have developed a fundamental tendency to preferentially attend to eyes in the environment. The empirical evidence to support this intuition is, however, remarkably thin. Over the course of eight chapters, the present thesis considers the area of social attention, and what special role (if any) the selection of eyes has in it. Chapters 2 and 3 demonstrate that when observers are shown complex natural scenes, they look at the eyes more frequently than any other region. This selection preference is enhanced when the social content and activity in the scene is high, and when the task is to report on the attentional states in the scene. Chapters 4 and 5 establish that the bias to select eyes extends to a variety of tasks, suggesting that it may be fundamental to human social attention. In addition, Chapter 5 shows that observers who are told that they will have to remember the scenes look more often at the eyes than observers who are unaware of the forthcoming memory test; moreover this difference between groups persists to scene recognition. Chapter 6 examines whether the preference for eyes can be explained by visual saliency. It cannot. Chapter 7 compares the selection of eyes to another socially communicative cue, the arrow. The results shed light on a recent controversy in the social attention field, and indicate again that there is a fundamental bias to select the eyes. Collectively the data suggest that for typically developing adults, eyes are rich, socially communicative stimuli that are preferentially attended to relative to other stimuli in the environment. / Arts, Faculty of / Psychology, Department of / Graduate

It is well established in developmental science that 14-month-old infants have significant difficulty associating pairs of objects with pairs of words that differ by a single phoneme (i.e., minimal pairs). This study used a traditional switch procedure in two experimental conditions (i.e., no face versus face with shifting gaze) to habituate infants with objects and minimal pair labels. Additionally, infants participated in a joint attention task and parents completed questionnaires related to family demographics and infant health and development, to compare to switch task performance. It was expected that infants' difficulty with minimal pair associative learning would be replicated in the no face condition. It was also predicted that the addition of a female face and the cues it could provide would abate the challenge that this task typically presents. As a group, infants' performances in the two conditions were not significantly different from each other and were not significantly different from chance. Analyses explored the relations between switch performance, joint attention task performance and questionnaire data, resulting in a significant correlation between performance in the face condition of the switch task and number of ear infections (r = .62, p < .05). Taken together, the addition of a female face with shifting gaze to a challenging word learning task does not sufficiently attenuate the cognitive load created by the task. The implications of these results are discussed further. / Master of Science

Social engagement has been clearly associated with socio-developmental outcomes in clinical and at-risk populations of infants, who show deficits in gaze following, face processing, and joint attention. Importantly, these are all skills related to language learning. This is most prominently illustrated by individuals with autism, for whom social engagement and language are markedly dysfunctional. In contrast, for typically developing infants the parameters of social engagement and language learning have only been generally defined. The present study was designed to relate infants' social attention to later language outcomes. In this longitudinal study, 11-month-old infants participated in social attention tasks (distracter, gaze following and face scanning tasks); at 14 months, infants returned to participate in language (word/object association) and joint attention (Early Social Communication Scales) tasks; at 18-20 months, caregivers reported on language (vocabulary size) and autistic symptomatology (developmental screening measures). Overall, the results indicated that measures of social attention predict later language outcomes. In particular, joint attention accounted for 13% of the variance in infants' word/object association performance at 14-months. More frequent response to the joint attention bids of an adult female tester (e.g., looking in the direction of her pointing) was associated with better word/object association learning. With regard to vocabulary size, two tasks emerged as significant predictors, the distracter and joint attention tasks, which together accounted for 38% of the variance in language at 18-months. Specifically, longer latencies (i.e., less distractibility) to look away from the face when an adult female was speaking (distracter task) and more frequently responding to the attention bids of the tester were associated with a larger productive vocabulary size. / Ph. D.

Autism Spectrum Disorders (ASD) are an urgent health concern as new reports indicate approximately 1 in 110 children are affected by ASD (Centers for Disease Control and Prevention, 2009). Although children with ASD struggle with social interactions, quantitative meta-analyses have revealed that traditional social skill interventions only produce minimal effects (Bellini, Peters, Benner, & Hopf, 2007). Due to these minimal effects, this study diverged from the common understanding of social skill deficits and introduced an autonomic nervous system circuit as one root of social behavior problems. Children with ASD show a "fight-flight" (i.e., sympathetic) state at baseline and to unfamiliar individuals (e.g., Bal et al., 2010). Research indicates, however, that music has the ability to calm cardiovascular functioning (Iwanaga, Kobayashi, & Kawasaki, 2005) and improve social behaviors in children with ASD (Whipple, 2004). This study recruited participants (N = 23) between 4-7 years old with a previously diagnosed ASD. Each participant was assigned to a Music group, n = 11, or an Audiobook group, n = 12. The 90-minute experimental session consisted of a receptive vocabulary assessment and psychophysiological monitoring during a baseline video, social engagement task, listening period, and a recovery video. A soothed autonomic state was measured by increased high frequency heart rate variability and decreased heart rate. Results indicated a significant soothing effect for the Music group. Moreover, the Music group evidenced a significant increase in social attention (e.g., joint attention and sharing emotions) relative to the Audiobook group. Mediation analyses may reveal partial mediation for the soothed autonomic state on the relationship between group and social attention improvements. Thus, these results suggest that social skill interventions may not be targeting a core element of social deficits (i.e., over-aroused autonomic state). / Master of Science

During collaboration, people communicate using verbal and non-verbal cues, including gaze cues. Spoken language is usually the primary medium of communication in these interactions, yet despite this co-occurrence of speech and gaze cueing, most experiments have used paradigms without language. Furthermore, previous research has shown that myriad social factors influence behaviour during interactions, yet most studies investigating responses to gaze have been conducted in a lab, far removed from any natural interaction. It was the aim of this thesis to investigate the relationship between language and gaze cue utilisation in natural collaborations. For this reason, the initial study was largely observational, allowing for spontaneous natural language and gaze. Participants were found to rarely look at their partners, but to do so strategically, with listeners looking more at speakers when the latter were of higher social status. Eye movement behaviour also varied with the type of language used in instructions, so in a second study, a more controlled (but still real-world) paradigm was used to investigate the effect of language type on gaze utilisation. Participants used gaze cues flexibly, by seeking and following gaze more when the cues were accompanied by distinct featural verbal information compared to overlapping spatial verbal information. The remaining three studies built on these findings to investigate the relationship between language and gaze using a much more controlled paradigm. Gaze and language cues were reduced to equivalent artificial stimuli and the reliability of each cue was manipulated. Even in this artificial paradigm, language was preferred when cues were equally reliable, supporting the idea that gaze cues are supportive to language. Typical gaze cueing effects were still found, however the size of these effects was modulated by gaze cue reliability. Combined, the studies in this thesis show that although gaze cues may automatically and quickly affect attention, their use in natural communication is mediated by the form and content of concurrent spoken language.

Emerging research suggests that many adults with Autism Spectrum Disorder (ASD) experience impairing Social Anxiety Disorder (SAD) or social anxiety symptoms (e.g., Joshi et al., 2013; Kleinhans et al., 2010), yet there is little guidance or agreement about how to best assess social anxiety in this population. Direct examination of overt eye gaze patterns may help determine if the attentional biases often reported in people with SAD also operate in those with ASD and co-occurring social anxiety. This study sought to assess the influence of social anxiety on gaze patterns in adults with ASD. An exploratory aim was to better understand the phenomenology of SAD within ASD. Three groups of participants were included: adults with ASD (n = 25), adults with SAD (n = 25), and adults without ASD or SAD (n = 25). As hypothesized, a large subset (n = 11; 44%) of the participants with ASD met diagnostic criteria for SAD. Contrary to study hypotheses related to gaze patterns, however, there was no evidence for gaze vigilance followed by avoidance for socially threatening stimuli in either the ASD or SAD groups, and there was no relationship between fear of negative evaluation and gaze duration toward socially threatening stimuli within the ASD group. Possible reasons for these null findings are considered. Clinical implications and suggestions for future research are also discussed. / Ph. D.