The Social Brain and Social Perception Neuroimaging Studies of - PDF document

The Social Brain and Social Perception Neuroimaging Studies of Autism: A Review of the Existing Literature and New Directions � The Social Brain : the complex network of Sarah Shultz, PhD areas that enable us to recognize other Assistant Professor Department of Pediatrics individuals and to Emory University School of Medicine evaluate their mental � Co-Director of the Pediatric Neuroimaging Core states (e.g. intentions, Marcus Autism Center Children’s Healthcare of Atlanta dispositions, desires, and beliefs) (Brothers, 1990) Figure from Allison, Puce, & McCarthy, 2000, TICS Marcus Autism Center 2 The Social Brain and Social Perception Social Brain Dysfunction in ASD Inferior Parietal Neural Mechanisms Associated with Face Processing in ASD: Inferior MPFC Lobule TPJ Frontal � Gyrus • The fusiform gyrus and the amygdala of individuals with ASD responds less to faces compared with typically- STS Temporal developing controls (e.g. Schultz et al., 2000) Poles Figure from Kennedy & Adolphs, 2012, TICS Schultz, 2005, Intl. J. Dev. Neuro. Marcus Autism Center Marcus Autism Center 3 4 Social Brain Dysfunction in ASD Social Brain Dysfunction in ASD Neural mechanisms associated with perception of biological Neural mechanisms associated with mentalizing in ASD motion in ASD: • Individuals with ASD show reduced STS activation when viewing biological motion (Herrington et al., 2007; Frietag et al., 2008) • The STS shows reduced sensitivity to the intentions underlying actions in ASD (Pelphrey et al., 2005) • Sibling studies reveal potential ‘compensatory mechanisms’ for processing biological motion (Kaiser et al., 2010) red: state activity blue: trait activity green: compensatory activity Mar Marcus Autism Center Marcus Autism Center 5 6

Social Brain Dysfunction in ASD Connectivity Neural mechanisms associated with mentalizing in ASD • Individuals with ASD show reduced activation in MPFC, STS and temporal poles when viewing animations that elicit mentalizing in typical viewers (Castelli et al., 2002) � • Theory of mind tasks yield abnormal patterns of activation in the MPFC (Happé et al., 1996) � • Activation of the mirror neuron system is decreased in ASD (Dapretto et al., 2006) Marcus Autism Center Marcus Autism Center 7 8 A Developmental Perspective on the Social Autism: A disorder of brain connectivity? Brain • ASD may be characterized How should we interpret findings of brain dysfunction in by high local connectivity ASD? and reduced long-range � connectivity (Just et al., • Does social brain dysfunction cause the symptoms characteristic 2004) of ASD? • Abnormal connectivity has � • Or, are the observed brain differences the result of having been reported between ASD? components of the social brain rather than everywhere in the brain Gotts et al., 2012, Brain (Gotts et al. 2012) Marcus Autism Center Marcus Autism Center 9 10 A Developmental Perspective on the Social Brain and behavior mutually shape and Brain constrain one another Increasingly Refined Dyadic Social Interaction Normative Neonate Interaction Social & Brain Development socialization Development in Autism Spectrum Disorders development Figure adapted from Jones & Klin (2009) Grelotti et al., 2005, Neuropsychologia Marcus Autism Center Marcus Autism Center 11 12

A Developmental Perspective on the Social Neuroimaging Studies of Infants at High and Brain Low-Risk for ASD Increasingly Refined Dyadic Social Interaction Normative Neonate Interaction Social & Brain Development socialization Development in Autism Spectrum Disorders development Figure adapted from Jones & Klin (2009) Marcus Autism Center Marcus Autism Center 13 14 Eye Fixation in Infants with ASD Relative to The Development of Smiling Typically-Developing Norms • Birth to ~2 months �� �� – newborns smile spontaneously in the absence of external percent fi xation on eyes � stimulation �� �� – occurs most often during sleep or during transitions to �� �� wakefulness (Emde, 1972) TD � �� �� ASD �� �� mean 95% CI �� �� �� �� • ~2 months � � � � � � � � � � � � � � �� �� �� �� �� �� �� �� – social smiling (smiling that is linked to the actions or age (months) vocalizations of a communicative partner) emerges (Emde, TD, N=25, male, 1637 trials Jones & Klin, 2013, Nature 1972) ASD, N=11, male, 747 trials Marcus Autism Center Marcus Autism Center 15 16 Social Smiling in 2- to 5-Month-Old Caregiver Behavior During Infant-Caregiver Infants Interactions Rachel Sandercock TD (n = 15 dyads, Percent of Interaction Time 25 sessions) ASD (n = 5 dyads, 9 sessions) ns ns ns ns Caregiver Behavior Infant Affect Infant Gaze • Neutral • Neutral • Towards • Talking • Fussy caregiver • Smiling • Smiling • Away from Neutral Talking Smiling Talking & • Smiling and talking caregiver Smiling Marcus Autism Center Marcus Autism Center 17 18

Infant Behavior During Infant-Caregiver Measuring contingency between infant Interactions smiling and caregiver actions TD (n = 15 dyads, 25 sessions) ASD (n = 5 dyads, 9 sessions) �� �� �� �� Infant Affect Infant Gaze % Change in Rate ns �� of Infant Smiling ns �� Interaction Time Percent of ����� ���� ���� ���� ���� ��� ��� ��� ��� ��� ns ��� ns ��� ns ��� ��� Neutral Fussy Smile Away Towards Caregiver From ���������������������� Time (in milliseconds) Caregiver Marcus Autism Center Marcus Autism Center 19 20 Measuring contingency between infant Measuring contingency between infant smiling and caregiver actions smiling and caregiver actions �� �� �� �� �� �� Increase in Infant �� �� % Change in Rate Smiling (p % Change in Rate �� �� of Infant Smiling of Infant Smiling < .05) �� �� ����� ���� ���� ���� ���� ��� ��� ��� ��� ��� ����� ���� ���� ���� ���� ��� ��� ��� ��� ��� ��� ��� ��� ��� Decrease in Infant ��� ��� Smiling (p ��� ��� < .05) Time (in milliseconds) Time (in milliseconds) Marcus Autism Center Marcus Autism Center 21 22 Measuring contingency between infant Contingency Between Typical Infant Smiling smiling and caregiver actions and Caregiver Behavior (n=15 dyads, 25 sessions) �� �� �� Infant Smiling Relative to Caregiver �� Infant Smiling Relative to Caregiver Smiling Talking & Smiling % Change in Rate Time, ms Time, ms �� of Infant Smiling % change in rate % change in rate of infant smiling of infant smiling �� No Change ����� ���� ���� ���� ���� ��� ��� ��� ��� ��� ��� ��� ��� ��� Time (in milliseconds) Marcus Autism Center Marcus Autism Center 23