Anxiety Disorders and Sensory Over-Responsivity in Children with Autism Spectrum Disorders: Is There a Causal Relationship?

“The amygdala has been implicated in anxiety disorders, mainly due to its central role in fear conditioning (e.g., Davis 1992; Garakani et al. 2006; Rauch et al. 2003).”

“However, Mogg and Bradley (1998) describe anxiety as a preattentive bias towards threat, and theorize that the automatic encoding of threat without elaborative processing leads to anxiety.”

“Currently, SOR can be identified in infants later diagnosed with ASD (Zwaigenbaum et al. 2005), which is much earlier than anxiety is usually diagnosed.”

“There is evidence that children with ASD have increased amygdala volumes compared to typically developing children, and that amygdala size is positively correlated with anxiety and severity of social-communication symptoms in these children (Amaral et al. 2008; Juranek et al. 2006).”

“Anxiety disorders are very common in children with autism spectrum disorders (ASD), and can increase the functional impairment of these children (Lainhart 1999; White et al. 2009 ).”

“In particular, MacLeod et al. (2002) demonstrated that training individuals to have an attentional bias towards threat-relevant words subsequently increased their negative response to stress.”

“It is also important to ask whether, theoretically, a preverbal child with low cognitive ability can be anxious, as some theories of anxiety relate anxiety to conscious cognitive processing and anticipation of future events (e.g., Beck and Clark 1997 ).”

“The amount of enhancement in the sensory response is correlated with the amount of amygdala activation, which suggests that children with SOR may have over-active amygdalas (Zald 2003).”

“Reports of SOR rates of 56–70% in children with ASD (Baranek et al. 2006; Ben-Sasson et al. 2007b) indicate elevated levels of SOR relative to rates of 10–17% in the general population (Ben-Sasson et al. 2009; Ben-Sasson et al. 2007b).”

“This may be an indicator of poor modulation of vestibularproprioceptive input, which is often observed in children with SOR ( Miller et al. 2007 ).”

“…have found rates of anxiety disorders and symptoms to be higher in children with ASD than in typically developing (TD) children (Gadow et al. 2004; Kim et al. 2000; Muris et al. 1998; Sukhodolsky et al. 2008; Weisbrot et al. 2005) and children with intellectual disability (Brereton et al. 2006).”

“Animals who have experienced context conditioning become behaviorally avoidant (Bouton and King 1983), and likewise children with SOR often become avoidant of generalized locations such as restaurants, grocery stores, or parties in addition to specific objects (Schoen et al. 2008).”

“Recently, a few studies have shown Cognitive Behavioral Therapy (CBT) to be efficacious in treating anxiety in children with ASD (e.g., Chalfant et al. 2007; Reaven and Hepburn 2003; Sofronoff et al. 2005; Sze and Wood 2007; Wood et al. 2009 ).”

“Exposure therapy could be combined with sensory stimulation intervention, such as body pressure, which would help decrease arousal (Baranek 2002) and make exposure less”

“Physiological studies that include adequate sample sizes and control groups (as suggested by Rogers and Ozonoff 2005), use sensory stimuli that are aversive to children with ASD, and examine subgroups of children with ASD, particularly those with anxiety symptoms.”

“…have found rates of anxiety disorders and symptoms to be higher in children with ASD than in typically developing (TD) children (Gadow et al. 2004; Kim et al. 2000; Muris et al. 1998; Sukhodolsky et al. 2008; Weisbrot et al. 2005) and children with intellectual disability (Brereton et al. 2006).”

“…have found rates of anxiety disorders and symptoms to be higher in children with ASD than in typically developing (TD) children (Gadow et al. 2004; Kim et al. 2000; Muris et al. 1998; Sukhodolsky et al. 2008; Weisbrot et al. 2005) and children with intellectual disability (Brereton et al. 2006).”

“This pairing of a conditioned stimulus (the loud noise) with a physiological reaction (e.g., fight-or-flight response) is known as interoceptive conditioning and is present in many different anxiety disorders (Razran 1961).”

“Recently, a few studies have shown Cognitive Behavioral Therapy (CBT) to be efficacious in treating anxiety in children with ASD (e.g., Chalfant et al. 2007; Reaven and Hepburn 2003; Sofronoff et al. 2005; Sze and Wood 2007; Wood et al. 2009).”

“The amygdala has been implicated in anxiety disorders, mainly due to its central role in fear conditioning (e.g., Davis 1992; Garakani et al. 2006; Rauch et al. 2003 ).”

“Because context conditioning is associated with unpredictability and hippocampus activation (Grillon 2008), it is more characteristic of anxiety than fear.”

“Children with SOR often react negatively to noisy or visually complex environments, are bothered by tags or seams on their clothing, or may dislike being touched unexpectedly (Liss et al. 2006).”

“Recently, a few studies have shown Cognitive Behavioral Therapy (CBT) to be efficacious in treating anxiety in children with ASD (e.g., Chalfant et al. 2007; Reaven and Hepburn 2003; Sofronoff et al. 2005; Sze and Wood 2007; Wood et al. 2009).”

“Reports of SOR rates of 56–70% in children with ASD (Baranek et al. 2006; Ben-Sasson et al. 2007b) indicate elevated levels of SOR relative to rates of 10–17% in the general population (Ben-Sasson et al. 2009; Ben-Sasson et al. 2007b).”

“Markram et al. (2008) examined the role of the amygdala in rats with ASD-like symptoms including repetitive behavior and reduced play and social behavior.”

“Specific phobia is one of the most common anxiety disorders seen in children with ASD (Gadow et al. 2004; Muris et al. 1998; Sukhodolsky et al. 2008), which is consistent with this fear and conditioning model, as it is easy to imagine how children with SOR might develop phobic responses to stimuli…”

“Some of these children also have a reduced range of facial affect and ability to express emotion appropriately (Yirmiya et al. 1989).”

“Specific phobia is one of the most common anxiety disorders seen in children with ASD (Gadow et al. 2004; Muris et al. 1998; Sukhodolsky et al. 2008), which is consistent with this fear and conditioning model, as it is easy to imagine how children with SOR might develop phobic responses to stimuli…”

“…have found rates of anxiety disorders and symptoms to be higher in children with ASD than in typically developing (TD) children (Gadow et al. 2004; Kim et al. 2000; Muris et al. 1998; Sukhodolsky et al. 2008; Weisbrot et al. 2005) and children with intellectual disability (Brereton et al. 2006).”

“Reports of SOR rates of 56–70% in children with ASD (Baranek et al. 2006; Ben-Sasson et al. 2007b) indicate elevated levels of SOR relative to rates of 10–17% in the general population (Ben-Sasson et al. 2009; Ben-Sasson et al. 2007b).”

“Very few toddlers (around 5–6%) with ASD are identified as having high rates of anxiety ( Ben-Sasson et al. 2008 ) but it is unclear whether that is due to actual low rates of anxiety or difficulty in identifying anxiety at this early age.”

“Keywords Autism spectrum disorders Anxiety Sensory over-responsivity Hyperarousal Sensory defensiveness Anxiety disorders are very common in children with autism spectrum disorders (ASD), and can increase the functional impairment of these children (Lainhart 1999; White et al. 2009).”

“Furthermore, children with anxiety disorders tend to regulate their negative affectivity through avoidance of stimuli that elicit fear (Craske 2003).”

“Sensory over-responsivity (SOR) is another common, and impairing feature found in more than half of children with ASD, and SOR has been linked to anxiety in children with ASD (Ben-Sasson et al. 2008; Liss et al. 2006; Pfeiffer et al. 2005).”

“It is still a controversial therapy, and while some studies show that it can improve children’s play and social-communication skills, there is little evidence that it specifically reduces SOR (Ayres and Tickle 1980; Case-Smith and Bryan 1999; Linderman and Stewart 1999).”

“The two conditions can be difficult to distinguish, as they both involve misperception of threat (e.g., Schoen et al. 2008) and overlap in their physiological (e.g., increased heart rate and skin conductance response) and behavioral (e.g., fight-or-flight response, emotional dysregulation,…”

“One way in which the two may be distinguished behaviorally is that SOR should be generalizable to multiple stimuli that elicit the unpleasant sensory response (e.g., several stimuli that create an aversive noise; see Miller et al. 2007) while specific phobia would be to one specific stimulus or situation (e.g. Ollendi…”

“It is still a controversial therapy, and while some studies show that it can improve children’s play and social-communication skills, there is little evidence that it specifically reduces SOR (Ayres and Tickle 1980; Case-Smith and Bryan 1999; Linderman and Stewart 1999).”

“As children with SOR by definition have an intense unconditional response to sensory stimuli, and as these stimuli are often elicited through factors completely outside the children’s control ( Reynolds and Lane 2008 ), one can see how these children are likely at high risk for fear conditioning.”

“The only ASD sensory intervention study that used anxiety as an outcome measure was conducted by Edelson et al. (1999).”

“Furthermore, if a child has a general anxiety disorder, by definition he or she should be generally anxious, not only to specific sensory stimuli (e.g., Masi et al. 2004 ).”

“Recently, a few studies have shown Cognitive Behavioral Therapy (CBT) to be efficacious in treating anxiety in children with ASD (e.g., Chalfant et al. 2007; Reaven and Hepburn 2003; Sofronoff et al. 2005; Sze and Wood 2007; Wood et al. 2009).”

“Recently, a few studies have shown Cognitive Behavioral Therapy (CBT) to be efficacious in treating anxiety in children with ASD (e.g., Chalfant et al. 2007; Reaven and Hepburn 2003; Sofronoff et al. 2005; Sze and Wood 2007; Wood et al. 2009).”

“There is evidence that children with ASD have increased amygdala volumes compared to typically developing children, and that amygdala size is positively correlated with anxiety and severity of social-communication symptoms in these children (Amaral et al. 2008; Juranek et al. 2006 ).”

“SSRIs used to treat anxiety in children may also reduce amygdala volume (Szeszko et al. 2004).”

“It is still a controversial therapy, and while some studies show that it can improve children’s play and social-communication skills, there is little evidence that it specifically reduces SOR (Ayres and Tickle 1980; Case-Smith and Bryan 1999; Linderman and Stewart 1999).”

“…with children, suggesting that relative to healthy controls, children with anxiety disorders show a stronger bias in selectively attending to threat-relevant stimuli, and difficulty disengaging from these stimuli even when they have been asked to attend to other information (Mobini and Grant 2007).”

“For example, weighted vests which provide continuous pressure (Ferterl-Daly et al. 2001) or touch therapy (e.g., massage; Baranek; Field et al. 1997; Silva et al. 2009) have been shown to improve young children with ASD’s responsiveness to sensory input, attention, stereotyped movements, and…”

“This is consistent with work outside the ASD literature showing a decrease in secondary anxiety symptoms in adults with SOR following a sensory-based intervention ( Pfeiffer and Kinnealey 2006 ).”

“Developing parent report and observation measures specific to ASD ( Davis et al. 2008 ) that make such distinctions is needed to analyze sources of stress in the frequent case that children are too young or lack the verbal skills to report their own symptoms.”

“Anxiety disorders are very common in children with autism spectrum disorders (ASD), and can increase the functional impairment of these children ( Lainhart 1999; White et al. 2009).”

“Although there are reports of the association of SOR and anxiety in individuals with other childhood and developmental disorders such as ADHD ( Reynolds et al. 2009 )w e chose to focus on ASD for the following reasons: (a) There are elevated rates of both conditions in individuals with ASD so determining causality bet…”

“For example, Plappert and Pilz (2002) found that mice that were genetically anxiety prone showed a stronger auditory startle reaction to sounds than non-anxious mice.”

“The discipline of the professional evaluating the child is not only likely to impact the child’s diagnosis but also the type of intervention the child is referred to. This problem was demonstrated by Ben-Sasson et al. (2007a) who found that occupational therapists were more likely to recommend a sensory-based interven…”

“Another factor which is thought to play an important role in anxiety in autism is sensory sensitivities (Green and Ben-Sasson 2010).”

“Although these areas of difficulty have been examined separately, studies have yet to examine the relations among these three conditions despite evidence suggesting that they may represent related and overlapping constructs (Campo et al. 2004; Green and Ben-Sasson 2010).”

“Green and Ben-Sasson (2010) proposed a model to explain how hyperreactivity in children with ASD can be characterized as hyper-attention to sensory stimuli and overreaction to those stimuli.”

“One explanation is that abnormal responses to high levels of sensory stimuli may be causative but this needs further exploration (Goldsmith et al. 2006; Green et al. 2010).”