Autism Spectrum Disorder. Aims for Session 3 03/04/2018. Neurodevelopmental Disorders Professor Pamela Heaton. Session 3

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1 Neurodevelopmental Disorders 2018 Autism Spectrum Disorder Professor Pamela Heaton Session 3 Autism Spectrum Disorder Aims for Session 3 Clinically evaluating Autism Spectrum Disorder Considering Autism traits in typical populations Aetiology of Autism Spectrum Disorder Early social/emotional development from Developmental Cognitive Neuroscience perspective Empirical studies into later developing social/emotional skills DSM-IV-TR (2000) DSM-5 (2013) Pervasive Developmental Autism Spectrum Disorders Disorder 1) Autistic Disorder 2) Asperger syndrome 3) Rett s Disorder 4) Childhood Disintegrative Disorder 5)Pervasive Developmental Disorder Not Otherwise Specified (PDD-NOS) DSM-IV-TR (2000) A. Social interaction B. Communication C. Imagination / Rigidity / Obsessions DSM-5 A. Social communication and interaction A B B. Imagination / Rigidity / Obsessions + unusual sensory responses DSM- 5 Criteria 1) Socio-communicative impairment across contexts as evidenced by all three of the following: Socio-emotional reciprocity Nonverbal behaviours used for social interaction Deficits in developing and maintaining relationships 1

2 2) Restricted and repetitive behaviour, interests and activities. At least two of the following: Stereotyped, repetitive speech, motor movements or use of objects Excessive adherence to routines, ritualised patterns of verbal/non-verbal behaviour or excessive resistance to change Highly restricted, fixated interests that are abnormal in intensity or focus Autism prevalence rates were estimated at 4 5 per 10,000 in the 1960 s The current prevalence for Autism is 1% in the general population ( e.g. Baxter et al., 2015). Diagnosing Autism Screening Instruments Childhood Autism Rating Scale (CARS) Brief assessment suitable for use with any child over 2 years of age. CARS assesses specific and relevant characteristics, abilities, and behaviours. Gilliam Autism Rating Scale (GARS) Assists teachers, parents, and clinicians in identifying and diagnosing autism in individuals ages 3 through 22. It also helps estimate the severity of the child s disorder. The Childhood Autism Spectrum Test or CAST (formerly the Childhood Asperger s Syndrome Test developed by Autism Research Centre in Cambridge) 39-item, yes or no evaluation aimed at parents for assessing the severity of autism spectrum symptoms in children. Sample questions from CAST 35. Does s/he care how s/he is perceived by the rest of the group? 36. Does s/he often turn conversations to his/her favourite subject rather than following what the other person wants to talk about? 37. Does s/he have odd or unusual phrases? Scores in the range indicate possible ASD or related social-communication difficulties. Autism Diagnostic Observation Schedule (ADOS) ADOS is considered to be a Gold Standard diagnostic tool. Individuals are evaluated using on of four available modules. Module 1 is used with children who do not consistently use phrase speech Module 2 is used with those who use phrase speech but are not verbally fluent Module 3 is used with fluent children Module 4 is used with fluent adults 2

3 Modules 1 and 2 require the test user and the child to move around the room Free Play Response to name Response to joint attention Bubble play Anticipation of a routine with objects Responsive social smile Functional and symbolic imitation Birthday party Response to Name - WellChildLens 2:38 9F5%... MODULE 3: for verbally fluent children Construction task Make-believe play Joint interactive play Demonstration task Description of a picture Telling a story from a book Cartoons Reporting a non-routine event/conversation Emotions Social difficulties/annoyance Break Friends/loneliness/marriage Creating a story MODULE 4: for fluent adults Construction task Telling a story from a book Description of a picture Demonstration task Cartoons Creating a story Conversation Current work/school Social difficulties/annoyance tch?v=ruu1fyc4xaq Break Emotions Daily living Friends/marriage Loneliness Plans and dreams Tasks within modules presents numerous opportunities for the individual being assessed to exhibit behaviours included in diagnostic criteria Presses for communication and social interaction Overall ratings are used to formulate a diagnosis through the use of a diagnostic algorithm which is provided for each module. Autism Diagnostic Interview Revised (ADI-R) Experienced clinical interviewer questions a parent or caregiver who is familiar with the developmental history and current behaviour of the individual being evaluated. It focused on three functional domains: Language and Communication Reciprocal Social Interactions Restricted, Repetitive and Stereotyped Behaviours and Interests Diagnostic Testing ADOS and ADI are rigorous tests used widely in research Diagnosis in clinical settings - reliance on expertise Implications for interpreting prevalence data 3

4 Autism Traits/Cognitive Style The Adult Autism Spectrum Quotient (AQ) Baron-Cohen, S. Wheelwright, R. Skinner, J. Martin and E. Clubley, (2001) Probes Social Skills, Attention Switching, Attention to Detail, Communication and Imagination. Aetiology Autism Spectrum Disorder Genetics Very high monozygotic twin concordance rates reported in some studies have been taken as evidence that ASD is highly heritable Research suggests that the genetic mechanisms involved are complex and include rare chromosomal anomalies, several individual genes of major effect and numerous common variants of small effect (Jeste & Geschwind, 2014) Jones, Gligaa, Bedford, Charman & Johnson (2013) Meta-analysis of prospective studies of infants (0 2/3years) with high familial risk for ASD (older sibling with a diagnosis) 20% of these high risk infants meet diagnosis by three years (Ozonoff et al., 2011) 10 20% develop sub-clinical ASD traits or other developmental difficulties (Messinger et al., 2013) Aetiology Autism Spectrum Disorder Environments Twin studies - Hallmayer et al., (2011) and Frazier et al.,(2014) reported significant influences of shared environments Lyall, Schmidt & Hart-Picciotto, (2014) - maternal prenatal vitamins (folate and fatty acid intake) & air pollution (e.g. heavy metals and particulate matter) But need rigorous large scale epidemiological studies Tick, Bolton, Happe, Rutter, & Rijsdijk (2015) Meta-analysis of twin studies Monozygote (MZ) Correlations were.98 Dizygotes Strict 67% Criteria 1% of population Loose Criterion 53% 5% Environmental/diagnostic effects change depending on diagnostic test used 4

5 Development from a Developmental Cognitive Neuroscience Perspective Johnson (2011) Symptoms of ASD is are likely to emerge from a complex interaction between pre-existing vulnerabilities, and the child s environment. Initial genetic and environmental risk factors interact to alter the development of brain structure and function, compromising the child s ability to learn from their environment Behaviours studied in at-risk infants Social/Communication TD individuals use mutual gaze, facial expression, posture and gesture to regulate social interactions Reduction or absence of these behaviours in early development in ASD? Responding to Social Interactions Typical infants show an early preference for faces over shapes, and for their own mothers face They become increasingly sensitive to changes in eye-gaze and gesture Move to preferential smiling Increasingly sensitive to other people s emotion cues Imitation (important for early social and cog dev) Jones & Klin (2013) carried out a longitudinal study of eye-gaze in 110 infants who were at high and low risk for ASD Eye-tracking used to measure visual scanning patterns in response to scenes of naturalistic caregiver interaction Data collected at 2, 3, 4, 5, 6, 9, 12, 15, 18 and 24 months Diagnostic status was ascertained at 36 months. For newborn children diagnosed with ASD, eye tracking was normal but showed a decline by 2 months. Ami Klin: A new way to diagnose autism TED Talk 19:44 /ami_klin_a_new_way_ to_diagnose_autism Ozonoff et al., (2010) reported a decline in social smiling and gaze to faces between 6 24 months Less shared positive affect at 14 months (Landa et al., 2007) Yoder et al., (2009) ability to combine gaze, gesture, and vocalisations between months predicted 36 month diagnosis and levels of social impairment 5

6 Superior Temporal Sulcus (STS) is sensitive to Biological motion Gaze Direction Facial Expression High risk infants show reduced STS response to social stimuli 5 mths (Lloyd-Fox et al., 2013) Infants who were diagnosed with ASD at 3 yrs showed atypical neural responses to gaze shifts at 6-9mths (Esabagh et al., (2012) Behavioural and neuroscientific evidence for early atypical social responses Implications/Downstream Effects of early abnormalities in social responding? Emotional Understanding Emotion Recognition in ASD Wide Range of paradigms used to test emotion recognition in children, adolescents and adults with ASD Social Development Emotion Recognition in ASD Meta-analysis carried out by Uljarevic & Hamilton (2012) on data from 48 studies (980 participants) revealed an emotion recognition impairment in ASD. Perception of fear more impaired than perception of happiness Teague et al., (2017) Review article of children with ASD showed that they can form selective, secure attachments. In seven samples using the Strange Situation procedure, 47% of children with ASD were classified as secure (n = 186). 6

7 Emotion Recognition in ASD Williams & Happe (2010) Tested 21 individuals with autism and 21 age- and IQ matched controls for their ability to (a) recognise, expressions of 'social' emotions (e.g., embarrassment) and 'non-social' emotions (e.g., happiness) in others (b) report their own previous experiences of each of these emotions. Both groups showed poorer recognition of social than non-social emotions. For both groups the ability to report personal social emotionexperience was significantly associated with the ability to recognise social emotions in others, independent of age and verbal ability Results reported no between-group differences in levels or patterns of performance on the experimental tasks How can we explain this? Implications/Downstream Effects of early abnormalities in social responding? Emotional Understanding Social Development DSM- 5 Criteria 1) Socio-communicative impairment across contexts as evidenced by all three of the following: Socio-emotional reciprocity Nonverbal behaviours used for social interaction Deficits in developing and maintaining relationships Experimental Studies of Social Cognition in ASD Classic example of false belief test Sally-Anne task (Baron-Cohen, Leslie & Frith, 1985) 7

8 The original study: Where will Sally look for her marble? Compare children with ASD, Down syndrome, and typical development 3-4 years TD: 85% pass DS: 86% pass ASD: 20% pass Q: Where will Sally look for her marble? A: Where she thinks it is. Baron-Cohen et al. (1985) First-order false belief tasks: actor has false belief about the world Second-order false belief tasks: actor has false belief about another person s belief about the world Mary doesn t know that the marble has been moved. Mary doesn t know that John knows that the marble has moved. ToM very widely investigated in Autism (Baron-Cohen review 2001) New strand of research in ASD Alexithymia Type 11. Characterised by difficulties in identifying and describing feelings, difficulties in distinguishing feelings from bodily sensations of emotional arousal, impaired symbolization and a tendency to focus on external events rather than on person experiences (Nehiam et al., 1976) Toronto Alexithymia Scale (TAS 20: Bagby, Parker & Taylor, 1994) Poses 20 questions including I am often confused about what emotion I am feeling It is difficult for me to find the right words for my feelings When I am upset, I don t know if I am sad, frightened, or angry am often puzzled by sensations in my body 8

9 Type 11 Alexithymia (Nehiam et al., 1976) (Hill et al., (2004), Berthoz & Hill, (2005) - severe or slight alexithymia in 85% of a sample of able adults with ASD Heaton et al., (2012) Strong association between Alexithymia test scores and the ability to categorise emotional vocalisations in HFA adults. Silani, et al., 2008 Adult participants with HFA and controls completed the Toronto Alexithymia Scale (TAS 20: Bagby, Parker & Taylor, 1994) Empathy was assessed using Davis Interpersonal Reactivity Index (IRI; Davis 1980) Participants were shown pictures from the International Affective Picture System (IAPS: Lang, Bagby & Cuthbert, 1999) Results 1) ASD participants had higher levels of Alexithymia than controls. Particular problems with describing feelings and insight 2) Significant correlation between measures of alexithymia and empathy (linking awareness of self and others) Internal task judge the level of emotion evoked by the picture External task judge the black/white colour balance (RT data) 3) RT data on internal and external tasks didn t distinguish groups (ASD participants were equally aroused) Alexithymia: fmri data In study by Silani et al., (2008) there was a Strong relationship between brain activity in the anterior Insula and the ability to assess ones own feelings in response to unpleasant pictures was observed. Theory of mind ability is associated with activation in: Medial prefrontal cortex Superior temporal sulcus Adjacent temporoparietal junction 9

10 Summary and Learning Outcomes Reviewed current screening instruments Key Readings Baron-Cohen, Leslie & Frith (1985) Considered early social/emotional development from Developmental Cognitive Neuroscience perspective Empirical studies into later developing social/emotional skills Silani et al., (2008) Williams & Happe (2010) Jones & Klin, (2013) 10