Motivation and emotion/Book/2016/Restricted interests and anxiety in children with autistic spectrum disorders

Restricted interests and anxiety in children with autistic spectrum disorders:
What is the relationship between restricted interests and anxiety in children with ASD?

Multimedia presentation (3 min)

Overview

A core feature of autism spectrum disorders (ASD) is a preoccupation with restricted interests (RI). In children, RI may be expressed through mediums such as fact collection and play-based activities (Spiker, Lin, Van Dyke, & Wood, 2012). Kanner (1943) indicated that these RI and fixed behavioural patterns were driven by anxiety. Subsequent research on this topic also supported the notion that RI in children with ASD are related to anxiety (Lidstone et al., 2014; Rodgers, Glod, Connolly, & McConachie, 2012; Spiker et al., 2012; Stratis & Lecavalier, 2013). Consequently, RI are often considered maladaptive and detrimental to the emotional well being of children with ASD. However, there is debate over whether or not anxiety should be considered a consequence or cause of the insistence on sameness and obsessional routines that are closely associated with RI (Gillott, Furniss, & Walter, 2001; Gunn & Delafield-Butt, 2015). More specifically, do RI cause anxiety in children with ASD? Or do these RI provide a coping mechanism for children with ASD and comorbid anxiety? The high prevalence of comorbid anxiety in ASD supports the need for an examination of the relationship between RI and anxiety in children with ASD (Spiker et al., 2012). RI are also less understood than other defining symptoms of ASD (Turner-Brown, Lam, Holtzclaw, Dichter, & Bodfish, 2011). This chapter will therefore discuss the relationship between RI and anxiety in children with ASD. Support for the links between anxiety and RI will be discussed, along with an alternative perspective outlining some of the positive aspects of RI.

Autism spectrum disorders (ASD)

Figure 1. Autism spectrum infinity awareness symbol.

What are ASD?

ASD and Pervasive developmental disorders (PDD) are often used interchangeably and are a very common childhood disorder (Filipek et al.,1999). ASD are a lifelong group of developmentally impairing disorders that have a significant effect on social skills, communication (both verbal and nonverbal), and repetitive behaviours or interests (Cervantes, Matson, Tureck, & Adams, 2013; Spiker et al., 2012; Stratis & Lecavalier, 2013). ASD typically begins in infancy and the severity of the disorder often dictates the initial diagnosis. Communication deficits are often the first indicator of an ASD (Lord, Cook, Leventhal, & Amaral, 2000). Social deficits on the other hand, may not be immediately evident, and are often not obvious until the child begins primary school (Lord et al., 2000).

Low and high functioning presentations of the disorder exist, with varied complexity and severity. As a result, no two children with ASD will present with exactly the same symptoms (Gunn & Delafield-Butt, 2015). However, core symptoms are evident across the autistic spectrum and they have been demonstrated consistently and measured reliably (Lord et al., 2000). The Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5) includes two defining features for ASD and the spectrum view of autism has replaced the previous categorical views of individual disorders such as autism and Asperger syndrome (AS). The two defining features for ASD include impairments to social communication/interaction and restricted and repetitive behaviours (American Psychiatric Association [APA], 2013). The low and high functioning presentations of the disorder are outlined below.

Low functioning autism Children with low functioning autism (LFA) show large deficits in comprehension and language skills, and poor attention skills (such as maintaining eye contact and responding to facial gestures). Deficits in communication are also evident and may serve as a source of frustration for a child with LFA (Duqutte, Michaud, & Mercier, 2007). Low functioning autistic children often present with sensory interests that may be compared to a typically developing nine month old child and they show limited skills in pretend play when compared to typically developing children (Duqutte et al., 2007). Severe behavioural concerns and mental retardation are also often evident in LFA (Lord et al., 2000).

High functioning autism High functioning autism (HFA) is considered to be a less severe form of autism (Gunn & Delafield-Butt, 2015). In contrast to low functioning autism, a delay in language development is not evident and there is normal, and sometimes high, intellectual ability (Tanidir & Mukaddes, 2014). There was some debate in the research as to whether or not Asperger syndrome (AS) is different to HFA because of an overlap of similar symptoms (Tanidir & Mukaddes, 2014). As a result, AS was often referred to interchangeably with HFA. However, the DSM-5, has now placed AS on the high functioning end of the autistic spectrum (APA, 2013). According to Asperger (1991), talking precedes walking in children with AS, which demonstrates the appropriateness of its place at the high end of the autistic spectrum.

Prevalence of ASD

Since the 1980s, the rates of ASD have increased dramatically (Cervantes et al., 2013). Rieske, Matson, May, and Kowlowski (2011) reported that approximately one in 150 children have an ASD. A year later, Baio (2012) reported an increase in ASD to one in 88 children {{where]]. According to Filipek et al. (1999) these ratios also appear to vary with IQ levels, where the rates of severely dysfunctional ASD were reported to be to be twice as common than those with average IQ. In support of this, Woodbury-Smith and Volkmar (2009) estimated the rates of AS to be five times less than low functioning autism. The rising occurrence of ASD has resulted in a greater emphasis on early intervention and research into comorbid disorders (Cervantes et al., 2013).

Genetic differences in childhood ASD

Males are four times (4:1) more likely, than females to have an ASD (Filipek et al.,1999; Hattier, Matson, Tureck, & Horovitz, 2011). According to Hartley and Sikora (2009) girls displayed more communication difficulties, problems with sleep, and anxiety, when compared to boys. However, boys exhibited more repetitive behaviours and RI than girls. Filipek et al. (1999) also suggested that fewer girls with a normal IQ might be diagnosed, possibly because they are more socially aware than males at an early age.

What are Restricted Interests (RI)?

Figure 2. A typical restricted interest of a child with ASD.

RI are the interests or hobbies that children with ASD participate in with focus and intensity (Gunn & Delafield-Butt, 2015; Honey, Leekam, Turner, & McConachie, 2007), and they are often considered odd or inappropriate (Spiker et al., 2012; Zandt, Prior, & Kyrios, 2007). RI are often expressed as obsessions and/or insistence on sameness (APA, 2013; Chowdhury, Benson, & Hillier, 2010; Gunn & Delafield-Butt, 2015; Lidstone et al., 2014). The RI of children with ASD are behavioural manifestations of restricted repetitive behaviours which are differentiated by lower level behaviours, such as stereotyped motor movements, and higher-level behaviours, such as RI (Woodbury-Smith & Volkmar, 2009). RI usually involve accumulation of large amounts of information about one particular topic and they are time intensive. This unusual level of intensity usually differentiates RI from the interests of their peers (Woodbury-Smith & Volkmar, 2009). RI can occur in both high functioning and low functioning presentations of ASD but they are more common in individuals with high functioning autism (Stratis & Lecavalier, 2013; Turner-Brown et al., 2011).

Autistic children often focus on details, which is a cognitive style that has been associated with stereotyped behaviours and RI (Chen, Rodgers, & McConachie, 2009). This cognitive style was reported to be associated with an individual’s repetitiveness and account for the occurrence of routines and RI (Chen et al., 2009). Repetitive behaviours are not confined to ASD. However, the repetitive behaviours that occur in ASD typically occur over a longer duration and occur significantly more often. They are also sustained with increasing age (Honey et al., 2007).

RI are also included in one of two subclasses in the Autism Diagnostic Interview-Revised (ADI-R), this insistence on sameness subclass includes “narrow interests, rigid routines, and rituals” (Lidstone et al., 2014, p. 82). Approximately 90% of children with ASD engage in RI (Spiker et al., 2012). Gunn and Delafield-Butt (2015) supported this high percentage and reported that RI in children with ASD might be as high as 75% of preschool children and 88% of primary school children.

Figure 3. 18-month old autistic child obsessively stacking cans.

Other names for RI include:

• Intense interests, obsessions, special fascinations, fixations, circumscribed interests, circumscribed topics, repetitive and narrow interests (Winter-Messiers, 2007).
• RI are also referred to interchangeably with special interests (Porter, 2012).

RI were first described by Kanner (1943), where a case study was described: “ He has gradually shown a marked tendency toward developing one special interest which will completely dominate his day’s activities. He talks of little else while the interest exists, he frets when he is not able to indulge in it (by seeing it, coming in contact with it, drawing pictures of it), and it is difficult to get his attention because of his preoccupation” (p. 233).

More recently, Winter-Messier (2007) defined RI as “passions that capture the mind, heart, time and attention of individuals with AS, providing the lens through which they view the world” (p. 142).

The Content and Expression of RI

The content, expression and intensity of RI are varied.  RI may be both typical and socially acceptable, or considered odd and sociably unacceptable (Spiker et al., 2012; Winter-Messiers, 2007). For example, one child may have a RI in trains (Porter, 2012), whereas another child might be focused lawn mowers (Attwood, 2007). RI may initially be age appropriate, such as a toddler’s interest in trains such as Thomas the Tank Engine. However, these obsessions are often not replaced with other interests as a child with ASD ages (Spiker et al., 2012). This may then result in the perception by society and the peers of a child, of abnormal behaviour.

Interestingly, a study on Turkish participants by Tanidir and Mukaddes (2014), indicated that the types of RI of participants were very similar to developed western countries, which may highlight that RI in children with ASD are universal in nature and not culture specific. Electronic devices, computers and technical interests were the most common RI. History, geography and science were also popular interests (Tanidir & Mukaddes, 2014). Lego, cartoon characters, aeroplanes and music were also reported as RI in this study. Turner-Brown et al. (2011) found that girls’ restricted interests were more social when compared to boys and the RI of girls mainly included activities such as music and movies. However, boys were more often preoccupied with objects and parts of objects.

Spiker et al. (2012) found that differences in expression of RI were also associated with anxiety. For example, RI expressed as attachment to objects was associated with obsessiveness and anxiety, whereas expression of RI through facts and memory was not related to symptoms of anxiety.

ASD and Comorbid Anxiety

Prevalence of ASD with comorbid anxiety   

Anxiety disorders are a common disorder in typically developing children with a prevalence rate of 5-10% (Rieske et al., 2011). However, anxiety occurs more frequently in children with ASD, when compared to children of typical development (Cervantes et al., 2013; Rieske et al., 2011; Settipani, Puleo, Conner, & Kendall, 2012). The prevalence rates of anxiety in children with ASD range from 11%-84%, with an average rate of 40%-50% (Stratis & Lecavalier
, 2013; van Steensel, Bögels, & Perrin, 2011; White, Oswald, Ollendick, & Scahill, 2009; Wigham, Rodgers, South, McConachie, & Freeston, 2015). According to van Steensel et al. (2011), anxiety is the second most common comorbid disorder in ASD (disruptive behaviour disorders are the most common). However, according to Tanidir and Mukaddes (2014), anxiety is the most common.

ASD and comorbid anxiety across the spectrum    

Anxiety disorders occur across the full autistic spectrum. However, White et al. (2009) and Settpani et al. (2012) suggested that anxiety disorders occur at higher rates in HFA, when compared to LFA. It was also argued that higher expressed anxiety is associated with HFA, whereas the level of experienced anxiety is the same across different levels of the autistic spectrum (Rieske et al., 2011). Anxiety can significantly interfere with an individual’s level of functioning. However, it can be more debilitating for children who have ASD because of the adverse effects on other symptoms of ASD (Reaven, 2009).

High levels of anxiety in children with ASD may be due to the difficulties with change and high levels of unpredictability encountered with ASD (Spiker et al., 2012). According to Settipani et al. (2012), children with ASD may also present with a pattern of anxiety disorders that differ to children without ASD. This includes a higher rate of specific phobias such as fears of physical injury. Zandt et al. (2007) also reported on the similarities between RI and OCD because both disorders result in repetitiveness. However, repetitive thoughts in OCD are usually unpleasant which is in contrast to the repetitiveness of RI. Not all children with ASD present with comorbid anxiety, which supports the notion that anxiety is not a core feature of ASD (Wood & Gadow, 2010).

Types of anxiety in ASD    

• Specific phobia 30%
• Obsessive compulsive disorder 17%
• Social anxiety and agoraphobia 17%
• Generalised anxiety disorder15%
• Separation anxiety disorder 9%
• Panic disorder 2%  (van Steensel et al., 2011)

Anxiety Model

Cognitive models of anxiety have been developed to help explain the associated variables of anxiety. Dugas, Gagnon, Ladouceur, and Freeston (1998) proposed a model of anxiety, with the identification of four cognitive variables. These are listed below:

1.  Intolerance of uncertainty (IU)
2.  Poor problem orientation
3.  Cognitive avoidance
4.  Positive beliefs about worry

Intolerance of uncertainty is an assumption that stress is associated with uncertainty, with unexpected events and change considered negative and as a result, to be avoided (Rodgers et al., 2012). The insistence on sameness seen in ASD is similar to the construct of intolerance of uncertainty, and anxiety is characterised by intolerance of uncertainty (Rodgers et al., 2012). Greenway and Howlin (2010) suggested that the daily difficulties and challenges for children with ASD might contribute to the development of RI and insistence on sameness. However, the insistence on sameness, in particular, RI may provide short-term relief from the anxiety caused by the unknown because they provide a restriction of the environment (Rodgers et al., 2012). Unfortunately, this may perpetuate a cycle of dependency whereby positive emotions and amelioration of anxiety through engaging in RI leads to long term use, resulting in dissociation with the social world, increased reliance on RI, and continuation of the anxiety cycle (Rodgers et al., 2012). 

The role of RI in anxiety in children with ASD

RI have been considered as a method of coping in an attempt to maintain homeostatic balance, with RI playing a role in increasing or decreasing sensory stimulation when an individual is under or over aroused (Lidstone et al., 2014). However, The relationships between RI and anxiety in children with ASD are not well understood. Some research, for example Spiker et al. (2012), suggested that RI serve as an avenue to decrease anxiety. Therefore, RI are consequential to anxiety because they act as a coping strategy, given the absence of other more effective coping strategies in children with ASD. Along these lines, Lidstone et al. (2014) reported that RI might act as a behavioural defence against anxiety in children with ASD. Therefore, RI may play a vital role in controlling and decreasing anxiety (Lidstone et al., 2014; Spiker et al., 2012). In contrast, the research also indicated that anxiety is a consequence of RI in children with ASD. The high intensity levels of RI may cause distress and therefore predispose children with ASD to increased levels of anxiety (Rodgers et al., 2012). Anxiety may also be induced when attempts are made to disrupt participation with a child’s RI (Gillott et al., 2001). Despite the varied opinions concerning the relationship between RI and anxiety in children with ASD, it is clear that increased levels of anxiety in ASD have been associated with RI (Gillott et al., 2001; Lidstone et al., 2014; Rodgers et al., 2012; Spiker et al., 2012). This strengthens the links between RI and anxiety in children with ASD. 

Are RI Harmful or Helpful?

RI are often considered abnormal, difficult to eliminate and/or socially unacceptable (Attwood, 2007). In this case, they are considered problematic. However, pursuing RI involves self-motivated learning about a particular topic, which may develop into expertise on the topic and vocational success, especially if the topic is considered socially acceptable (Attwood, 2007). Therefore, RI may be considered both harmful and helpful with regards to learning and social settings. Below is a list outlining the harmful and helpful aspects of RI.

Table 1. The harmful and helpful aspects of RI.

Harmful
RI can be distressing to the individual and their family because of the intensity of engagement (Woodbury-Smith & Volkmar, 2009). RI can limit the ability of children to learn and fit in with their peers (Porter, 2012; Stratis & Lecavalier , 2013). They may also cause rejection from peers due to the sometimes socially unacceptable nature of these interests (Spiker et al., 2012). RI can interfere with an individual’s ability to function on a daily basis (Winter-Messiers, 2007). RI may be pursed at the exclusion of other activities such as physical fitness (Turner-Brown et al., 2011; Winter-Messiers, 2007). Restriction from RI may result in irritability or aggression (Turner-Brown et al., 2011). The rigid nature of RI and/or inflexibility may interfere with learning, communication and participation in social settings (Turner-Brown et al., 2011). A child may experience frustration as a result of being misunderstood with regards to their RI (Spiker et al., 2012). A child may have a negative self image when not involved with their RI (Spiker et al., 2012). The passion for RI can be detrimental when taken to extremes (Attwood, 2007).
Helpful
RI may be seen as a unique strength or cognitive skill (Turner-Brown et al., 2011). RI are a pleasurable experience and are considered to be intrinsically motivating (Spiker et al., 2012). The obsessional routines associated with RI have been associated with a sense of organisation (Zandt et al., 2007). Success and talents can be developed in the area of RI (Spiker et al., 2012). Children with ASD show increased vocabulary and syntax on the topic of their RI (Winter-Messiers, 2007). Children with ASD show increased enthusiasm and positive affect, such as pride and happiness, when asked about their RI (Spiker et al., 2012). Improved eye contact and expressive gestures have been associated with discussion about a child’s RI (Winter-Messiers, 2007). Children show decreased levels of distraction when focused on their RI (Winter-Messiers, 2007). RI may be used as a coping strategy to help self-regulation for stress, anxiety and negative emotions (Winter-Messiers, 2007). Children with ASD experienced increased motivation to learn and there have been positive gains for learning when RI are incorporated into classroom activities (Gunn & Delafield-Butt, 2015). RI can facilitate friendships with children who share the same interest (Gunn & Delafield-Butt, 2015).

RI and Self-Image

RI are also considered beneficial to children with ASD because a child with ASD will often define themselves by their RI. A child’s RI consumes them and therefore RI are very important to the well-being of children with ASD (Gunn & Delafield-Butt, 2015). These children do not want their RI to be considered lightly and if the importance of a child’s RI is denied, his or her identity may be threatened. This may result in decreased engagement in social settings and decreased self-confidence. Adverse effects on a child’s motivation to learn and the emotional well being of the child may also further increase the risk of anxiety (Gunn & Delafield-Butt, 2015; Winter-Messiers, 2007). The RIs of children can therefore be difficult to separate from a child’s self-image because they enable a child with ASD to interpret and make sense of their world (Winter-Messiers, 2007). As a result, children with ASD are often negative about themselves when they are not engaged in their RI (Gunn & Delafield-Butt, 2015).

Parental concerns

Some parents feel that the RI of their children interfere with learning and interactions with their peers (Gunn & Delafield-Butt, 2015; Woodbury-Smith & Volkmar, 2009). Stratis and Lecavalier
 (2013) reported that parents of children with ASD believe that RI can be one of the most frustrating symptoms of ASD to deal with because of the impact of RI on daily functioning. Tantrums are also a negative consequence of withdrawal from RI, due to the lack of flexibility associated with these interests (Duignan & Connell, 2015; Turner-Brown et al., 2011). Increased frequency of these occasions may also have adverse consequences for family well-being and therefore RI may be considered a significant challenge for parents.

Other primary concerns for parents of children with RI include:

•  Their child’s RI are not socially acceptable
•  The RI of their child is not age appropriate
•  RI may not lead to a successful career
•  RI cause a lack of interest in other family activities (Winter-Messiers, 2007).

Parents have also expressed a variety of emotions about their child’s RI. These include:

Table 2. The positive and negative feeling of parents regarding their child's RI.

Positive Feelings Pride, humor, fascination, pleasure, and enthusiasm. (Winter-Messiers, 2007)

Negative Feelings Boredom, frustration, and embarrassment. (Winter-Messiers, 2007)

Limitations

• The female samples were small in many of the studies and research with participants from diverse ethnic and socio-economic backgrounds was also limited. Although given the sex discrepancy with ASD, it is easy to see why much of the research has focussed on boys.
• Parental understanding of childhood anxiety may also be limited and be dependent upon parental interpretations of child behavioural problems and anxiety (Rodgers et al., 2012). However, most of the data collected on RI was based on parental reports and therefore it is possible that misinterpretations occurred because the behaviours of RI and anxiety are often difficult to differentiate (Spiker et al., 2012; Zandt et al., 2007).
• Unfortunately, problems also arise from self-reports of children with ASD because of the difficulties associated with introspection amongst ASD children (Gillott et al., 2001; Wood & Gadow, 2010). With this in mind, observational studies might be advantageous for further understanding on this topic.
• It was also difficult to understand the implications for RI and anxiety across the ASD population because the research focused on high functioning individuals on the ASD spectrum (Turner-Brown et al., 2011). This impacts on the ability to generalise the findings to children with ASD who are low functioning, and with learning disabilities.
• RI in ASD and compulsive behaviours in OCD can also be difficult to distinguish between, which may impact the results of anxiety research in children, especially given that both ASD and OCD have RI as a core feature (Rodgers et al., 2012; Spiker et al., 2012).
• There is also still uncertainty of the distinction between RI and interests of typically developing children. For example, a study by DeLoache, Simcock and Macari (2007) highlighted that RI occur in some children, especially boys, without ASD. However, the content of these interests are often different in children with ASD and RI are also associated with a greater degree of functional impairment  (Turner-Brown et al., 2007).

Conclusion

This chapter discussed the relationship between RI and anxiety in children with ASD. It was evident from the research that children with ASD, who participate in RI do show high levels of anxiety. This supported a link between comorbid anxiety and RI in children with ASD. The content and expression of RI also showed universality in the research. The harmful aspects of RI might suggest that RI need to be removed to facilitate learning and social acceptance. Yet, despite the reported negative consequences of RI, the research also suggested that there might be positive effects of RI on anxiety, in children with ASD. This alternative view outlined some of the helpful aspects of RI that may increase cognitive skills, positive affect and aid in beneficial self-regulation (Attwood, 2007). Therefore, engaging in RI might help children overcome anxiety and make sense of their world (Attwood, 2007).

Future research examining the nature of RI in ASD, when compared to other conditions such as OCD, and the understanding of RI across different age groups would be of benefit to clinical settings. Further research into the relationship between RI and ASD may also have implications for identifying the cause of RI and result in a greater understanding of the complexity of ASD (Stratis & Lecavalier, 2013). Finally, further investigations that examine the complexity of symptoms of RI in ASD and in particular, how the manifestation of RI in girls may differ to RI in boys may be advantageous (Chowdhury et al., 2010).

The RI of children with ASD need not be considered a barrier because there is an opportunity to acquire a talent. However, whether or not this is facilitated is dependent upon those who engage with these children. Teachers and parents therefore play a major role with regards to this (Rodgers et al., 2012).

See Also

• Motivation and emotion/Book/2015/Autism and emotional development
• Motivation and emotion/Book/2013/Intrinsic motivation
• File:Autism spectrum disorder video.webm

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Wigham, S., Rodgers, J., South, M., McConachie, H., & Freeston, M. (2015). The interplay between sensory processing abnormalities, intolerance of uncertainty, anxiety and restricted and repetitive behaviours in autism spectrum disorder. Journal of Autism and Developmental Disorders, 45(4), 943-952. doi:10.1007/s10803-014-2248-x

Winter-Messiers, M. A. (2007). From tarantulas to toilet brushes: Understanding the special interest areas of children and youth with asperger syndrome. Remedial and Special Education, 28(3), 140-152. doi:10.1177/07419325070280030301

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Zandt, F., Prior, M., & Kyrios, M. (2007). Repetitive behaviour in children with high functioning autism and obsessive compulsive disorder. Journal of Autism and Developmental Disorders, 37(2), 251-259. doi:10.1007/s10803-006-0158-2

External Links

autismspectrum.org.au

raisingchildren.net.au

positivepartners.com.au

autismspeaks.org

psychology_tools.com