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Motivation and emotion/Book/2019/Stimming motivation

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Stimming motivation:
What is stimming and what motivates people to do it?

Overview

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Stimming is any type of behaviour that involves repetitive physical movements, activities or verbal sounds

Remember the last time you had a job interview? Chances are, you felt a little nervous. Maybe you paced back and forth in the waiting room or sat quietly, tapping your leg up and down. Maybe you twirled a piece of your hair, fidgeted with your phone or even bit your fingernails! These behaviours are common and we use them every day to cope with the world around us.

Figure 1. Meticulous lining up objects is a form of stimming common in autism spectrum disorder.

The repetitive behaviours described above are form of "Stimming". The term stimming is most commonly used in autism spectrum disorder (ASD), as these behaviours are most prevalent in this group (see Figure 1 for an example) and form part of the diagnostic criteria for ASD (Lewis, Bodfish, Mcilvane, Bristol, & Alexander, 1998). The basic definition of stimming, however, suggests that stimming is not limited to ASD and it has been observed in various other groups such as schizophrenia patients (Lovaas, Newsom, & Hickman, 1987).

Research has been dominated by the psychological perspective of Behaviourism which asserts that stimming serves a functional purpose only; that is, to obtain or escape a stimulus (Lewis, Baumeister, & Mailman, 1987). Emerging research suggests otherwise and personal accounts from adults with ASD have illustrated that stimming is poorly understood by those not involved in the behaviour. Minimal social understanding and acceptance of stimming is linked to poor mental health in those with ASD; particularly depression and anxiety (Cage, Di Monaco, & Newell, 2018). These findings highlight the importance of investigation in this field and suggest that stimming may be motivated by underlying, internal mechanisms: emotion regulation, perceived control and the self.

Focus of this chapter
Explain Review Explore Discuss
What stimming is The limitations of historical and current approaches to stimming The three leading suggestions for stimming motivation (with emphasis on ASD) The everyday applications for stimming 

Case study: Part one

Meet Shane, a 35-year-old male diagnosed with ASD. Shane is non-verbal, which means that he cannot speak, so he uses small hand gestures to communicate with others. Shane attends a disability day-program on weekdays so that he can interact with others and be supported while engaging with the community. Shane’s favourite support worker is Imelda. She picks him up from his house each morning and drives him to the day-program where they spend time together participating in fun activities. Imelda has noticed that during their trips Shane often falls asleep. However, as they approach the centre, Shane wakes up and begins to flap his hands, rock back and forth in his seat and make a droning sound in his throat. Imelda has been advised that Shane does this stimming behaviour because he likes how it feels but Imelda is not so sure that this makes sense; there is a pattern to his behaviour, and she is curious to find out what is motivating Shane to do it.

See what is revealed in part two after reading the information in this chapter.   

What is stimming?

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The term "stimming" is a form of positive terminology embraced by the autism community (Kapp et al., 2019). This term encompasses a wide variety of repetitive motor and verbal behaviours (Joosten, Bundy, & Einfeld, 2012). Longitudinal research suggests that stimming can be emitted by neurotypical and clinical groups of people; "neurotypical" meaning the absence of developmental or psychological disorders (Leekam et al., 2007). Figure 2 provides a snapshot of the information in this section: what is stimming, who uses stimming, what stimming looks like and what brain mechanisms might be involved in stimming.

Figure 2. A summary: What is stimming?

Populations

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Stimming can be emitted by any individual, at any point across the lifespan; although it is most common in young children (Barrett et al., 2015). Populations that have received research attention in relation to stimming (or repetitive behaviour) include those with ASD, schizophrenia, obsessive-compulsive disorder, neurotypical children, neurotypical adults (particularly when under intense stress), individuals with blindness, and individuals with high levels of aggression (Joosten et al., 2012; Leekam et al., 2007; Lovaas et al., 1987).

Although evidence for stimming is largely found in relation to these populations, the general definition of stimming does not disqualify other populations from engaging in this behaviour.

Stimming is displayed in many varied forms, unique to the individual emitting the behaviour. In neurotypical individuals, stimming may take the form of fidgeting, running in circles, or nail biting (Barrett et al., 2015). In clinical populations stimming tends to present in more uncommon forms such as hand flapping, head banging or echolalia; see Table 1 for more examples (Lovaas et al., 1987).

Table 1.
A Description of Common Stimming Topographies Displayed in Autism Spectrum Disorder

Type Description
Hand flapping Repetitively shaking hands back and forth
Body rocking Rocking the body in a forward and backward motion
Echolalia Looped repetition of another's spoken word (e.g., "good boy, good boy, good boy")
Vocalisations Repetitive verbal behaviour (e.g., muttering, grunting, droning)
Lining up objects As seen in Figure 1, a compulsion to meticulously order or line up objects
Pacing Repeated steps in forward or backward motion
Head banging Repetitively connecting the head with another object or body part

Neurobiological mechanisms

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Scientific research has delivered few, and conflicting, studies regarding the neurobiological mechanisms of stimming. The main focus of research has emphasised stimming in ASD and has produced varied results. The inconsistency in research findings may be due to the wide variety of stimming topographies, ultimately any behaviour can become repetitive and as such, it is difficult to narrow down which brain structures are responsible. Table 2 summarises research findings that suggest various underlying neurobiological mechanisms that may be responsible for stimming.

Table 2.

Suggested Neurobiological Mechanisms Responsible for Stimming

Global braina

Behaviour is not linked to one particular area, rather there is difficulty in global brain integration due to enlargement of the brain.

Anterior cingulate cortexb

Dysfunction in this area is linked to impairments in judgement, prioritising attention, prediction, and response monitoring.

Parietal lobe & cerebellumc

Abnormality in these areas are linked to difficulties in sensory information processing and motor movement coordination.

Posterior parietal cortexd

Dysfunction in this area is linked impairment in planned movement, spatial reasoning, and attention.

Corticostriatal feedback circuitse

Dysfunction in these circuits impact the ability to select and control appropriate goal-directed behaviour; the circuits include the motor and pre-motor cortexes, the dorsolateral-prefrontal cortex, the orbitofrontal cortex, and the anterior cingulate cortex.

Note. a e Langen, Durston, Kas, van Engeland, & Staal, 2011; b Sinha et al., 2014; c Ravizza, Solomon, Ivry, & Carter, 2013; d Shafritz, Dichter, Baranek, & Belger, 2008

History

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Attitudes toward stimming have evolved over the decades since the 1970s, particularly in relation to treatment approaches. Despite this progression however, some historical beliefs are still widely accepted in the modern approach to understanding and treating stimming behaviour; namely, beliefs about the aetiology and function of stimming.

Historical approach

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Research investigations of stimming began in the 1970s to '80s and were dominated by the psychological Behaviourist approach; the focus was limited to only observable and measurable behaviour. The prominent theory of this era was the Perceptual Reinforcement Theory (Lovaas et al., 1987) which proposed that stimming occurred due to automatic reinforcement (i.e., it just felt good). This approach to stimming emphasised eliminating the behaviour due to reasons such as negative social judgement and physical harm. Original efforts to eliminate stimming were punishment-based, involving physical restraint and overcorrection (Lovaas et al., 1987).

Limitations

Critics of the Perceptual Reinforcement Theory have found that attempts to eliminate stimming are not effective; instead, the topography of the behaviour simply changes and stimming continues in a different form (Lewis et al., 1987). Additionally, there have been ethical concerns regarding the punishment-based intervention methods of this era (Cage et al., 2018).

Modern approach

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Fundamentally, modern approaches continue to characterise stimming as a learned behaviour that has reinforcing properties. Research has focussed on the functions of stimming and how these functions can result in certain reinforcing outcomes; for example, gaining attention from a caregiver (Lewis et al., 1987). As a result of these research findings, modern professionals attempt to replace stimming behaviour with functional alternatives, exercise, or modification of the environment; prioritising behaviour causing physical harm (Kapp et al., 2019; Petrus et al., 2008). Interventions aimed at replacing stimming behaviour have shown to be mildly successful, producing only short-term reductions in the behaviour (Petrus et al., 2008).

Limitations

While understanding the function of stimming has improved the management of this behaviour, research has begun to suggest that perhaps this is a reductionist view. Reinforcement is a source of external motivation, however, findings have shown that stimming may be the result of more complex and intrinsic emotional and cognitive motivations (Kapp et al., 2019).

Motivation

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Alternative motivation for stimming constitutes a new and limited field of research, however, researchers in this preparadigmatic phase are steadily piecing together significant factors to form the underpinnings of contemporary stimming-motivation theory. Many areas have been explored in this domain, however in terms of support from prominent motivational theory, the most promising areas for consideration include emotion regulation, perceived control and the self.

Emotion regulation

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Figure 3. The optimal arousal level lies between under-stimulation and over-stimulation.

A growing number of studies have identified emotion regulation as the highest reported motivation for stimming among individuals with ASD (Kapp et al., 2019). In a survey of 100 individuals with ASD, Kapp et al. (2019) reports that 72% of participants utilised stimming for anxiety reduction. Emotion regulation strategies commonly include cognitive reappraisals, seeking social support and problem-solving (Samson, Hardan, Podell, Phillips, & Gross, 2015), however due to neurobiological differences (see neurobiological mechanisms), individuals with ASD are not capable of possessing the full range of typical emotion regulation strategies. As a result of these differences, stimming behaviour in ASD may have developed as a method of managing heightened emotion: an emotion regulation tool (Samson et al., 2015). In the same way that neurotypical individuals may cover their ears when a loud noise occurs, those with ASD also have physical responses to overwhelming situations. Environments that are loud, bright, confusing and unpredictable can be anxiety-provoking and increase physiological arousal (Sinha et al., 2014). The way that individuals manage the physiological effects of extreme environments will often manifest through stimming behaviours, for example body rocking when overwhelmed; hand flapping when anxious; or jumping up and down when excited (Mays, Beal-Alvarez, & Jolivette, 2011).

Stimming Info 1.png
Figure 4. Examples of the way stimming is used to regulate arousal.

Arousal Theory of Motivation (Berlyne, 1960) supports the notion that the performance of certain behaviours can work to regulate emotion. Arousal theory proposes that individuals possess an optimal level of physiological and cognitive arousal (see Figure 3); if one becomes under-or-over stimulated the individual will seek out behaviours to either increase or decrease their level of arousal (see Figure 4). It is suggested that stimming behaviour is used to maintain optimal arousal by seeking out physical sensations to increase arousal (e.g., rubbing hands through a furry rug), or limiting the intake of external input to decrease arousal (e.g., narrowing one's focus to the movement of their flapping hands) (Mays et al., 2011). Most common in ASD, is the need for down-regulation of arousal and research suggests that stimming provides a rhythm with which one can regulate (e.g., one may align their breathing with back and forth pacing); interestingly this concept overlaps with the popular relaxation methodology of Mindfulness. Optimal arousal is associated with increased performance, pleasure and concentration, therefore if stimming does lead to optimal arousal, it should be considered an adaptive form of emotion regulation (Langen et al., 2011).

Perceived control

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Feeling in control of one’s life is an essential component of psychological wellbeing (Declerck, Boone, & De Brabander, 2006). The ability to intentionally and effectively control one’s environment (also known as personal-agency) contributes to a healthy and positive life experience. Remarkably, simply possessing the perception of control provides the same wellbeing outcomes and impacts one’s ability to elicit emotion regulation strategies (Declerck et al., 2006).

Reactance Theory (Brehm & Brehm, 1981) extends beyond the concept of “control over the environment” to suggest that individuals are more broadly motivated by control over their own freedom. Reactance is essentially a reaction to being denied control over one’s freedom, which serves to initiate and direct subsequent behaviours in an attempt to regain perceived control and therefore freedom. Modern research has suggested that reactance can also be triggered by the anticipation of an upcoming, uncontrollable or ambiguous situation; referred to as priming reactance (Steindl, Jonas, Sittenthaler, Traut-Mattausch, & Greenberg, 2015).

The application of Reactance Theory to stimming behaviour, in ASD, is connected to the characteristic desire for “sameness” in the environment (Sinha et al., 2014). In ASD, perceived control is extremely sensitive to change and stimming is considered a form of reactance to changes that disturb the "sameness" of the environment. Stimming allows an individual to focus on a single behaviour that they have control over, while simultaneously blocking other parts of the environment over which they have no control (Kapp et al., 2019).

Reactance Theory goes on to explain that the source of the reactance can be motivated internally or externally. Internally motivated reactance is a form of problem-solving that attempts to personally change the environment to regain one’s freedom. The alternative is externally motivated reactance, which can unfortunately lay the foundations for the development of learned helplessness (Brehm & Brehm, 1981). Stimming would be considered an internally motivated form of reactance which, in this context, is an appropriate and adaptive reactance strategy. Neurotypical individuals (such as those experiencing high levels of aggression) would also use an internally motivated form of reactance to physically alter their environment, however, in this context the resulting behaviour may not be appropriate or adaptive (Steindl et al., 2015).

The self

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As outlined in the chapter titled Self Concept, the notion of “self” can be described as one's understanding of themselves as a distinct individual; this involves mental representations of who one is, who they wish to become and who they are in comparison to others around them. Current research conducted by Perrykkad & Hohwy (2020) suggests that individuals with ASD use stimming behaviour as a form of self-evidencing; which means, as a way to verify one’s self-concept. Self-evidencing confirms one’s existence in the world and this information is sought out through acts of self-verification. Self-verification is the intentional pursuit of information that is consistent with one’s self-concept and therefore verifies what one knows about themselves.

In general, individuals will seek to confirm and verify their existence by pursuing the affirmation of others, through direct comparison with others, or by involving themselves in events that are consistent with their view of the self (Perrykkad & Hohwy, 2020). Individuals with ASD experience difficulty in social interaction and cognitive processing abilities, as such, there is limited capability to perform the same general methods of self-verification (Samson et al., 2015).

In pursuit of self-verification, an individual with ASD will instead choose to engage with sensory stimuli (stimming) that is predictable and reliable (Perrykkad & Hohwy, 2019a). The overarching motivational drive is the attempt to minimise the difference between one’s self-concept and what is presented in reality; referred to as minimising prediction error (Perrykkad & Hohwy, 2020). Stims are actions that have been performed many times before with unchanging results, therefore they are an excellent and reliable source of self-verification. Stimming is a fast and effective method for reducing prediction errors; one small movement can serve to satisfy the need for self-verification.

As this is an extremely new avenue of research, there is limited specific evidence for the link between self-evidencing and stimming behaviour. Rather, this research provides suggestions based on related theoretical framework and has begun to generate specific and testable hypotheses. Some hypotheses propose that echolalia can be seen as mimicking another person’s self in the initial stages of developing one’s own self-concept (Perrykkad & Hohwy, 2019a); in another example, it is suggested that prediction error is be reduced by the repetitive clicking of one’s pen (Perrykkad & Hohwy, 2020). In this approach, the ultimate aim of stimming is to minimise prediction error, which is motivated by the need to provide evidence of one’s own existence. Verification of the self enhances one’s perception that the world is predictable and coherent, which allows for personal-agency and enables emotion regulation.

Case study: Part two

Imelda did some research and found that she was not alone in noticing that there were some specific motivations behind Shane’s behaviour. She found that the reason Shane starts to stim, as they approach the centre, may be because he suddenly feels anxious that he doesn’t know what to expect when he arrives; who is at the centre? what is going in there?

Maybe Shane stims to regulate his anxiety and reduce his arousal. Imelda also found that along with his anxiety and uncertainty, Shane must feel very out of control; he doesn’t have a choice about whether or not he will go to the day-program, so maybe his stimming is reactance to try and regain some of his freedom and sense of control. As she continued to research, Imelda considered that when Shane wakes up from sleeping in the car, he is confronted with a different environment than when he fell asleep. This sudden change in his surroundings may motivate a need to self-verify so he uses stimming to make sure that he, and the world around him, is the same as when he fell asleep.

Imelda didn’t know which of these motivations may be the one for Shane, but she was able to use this information to support him when he was stimming. Imelda made sure she had relaxing music and a calming scent in the car to help him regulate his emotions; she asked for Shane’s help when choosing the music or opening the car door to increase perceived control; and she routinely made the same comments when Shane woke up from his sleep (e.g., “there’s our favourite tree, looks like we’re nearly there”) so that she could help him to minimise prediction errors which would assist in his self-verification process.

After a few months, Imelda noticed that Shane’s stimming behaviours had become less frantic and he had more relaxed days at the day-program. Shane became very warm toward Imelda; their bond had strengthened through her pursuit of understanding and supporting Shane in ways that mattered to him.

(Based on real-life events – details have been changed to protect the privacy of those involved)

Research applications

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The focus of research in the area of stimming concentrates on the ASD population, and rightly so. However, when considering stimming from a motivational approach and the positive outcomes that are brought about by the behaviour, there is an opportunity to apply this knowledge to the general population. Firstly though, it is important to consider the connotations of the term “stimming” and how we might preserve the integrity of this positive terminology when applying it outside of ASD. Perhaps instead, for neurotypical groups, the act of repetitive behaviour could be otherwise referred to as “fidgeting”, as suggested by Perrykkad & Hohwy (2020).

Regardless of the terminology used, the motivational understanding of repetitive behaviours can be broadly applied across a variety of individuals and situations. Consider for example, university students tirelessly bouncing their leg up and down as they listen to a lecture; possibly as a method for ensuring an optimal level of arousal to increase concentration and performance or perhaps, it is a method for calming the stress and anxiety of impending assessment tasks (Barrett et al., 2015).

The current attitude toward stimming supports the reduction of this behaviour, however, in light of emerging research in this area there are some important ethical concerns related to this approach. If stimming is truly motivated by emotion regulation, the need for personal control or used to verify the self, the reduction of this behaviour may have negative implications for an individual’s ability to cope, interact with the world and potentially understand their own sense of identity.

DO YOU STIM?

Join the conversation to share stories about your own experience and what motivates you to use stimming. Click here to join

Conclusion

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Stimming is a general term used to describe repetitive motor or verbal behaviours and can be experienced by any individual. Attitudes toward stimming are gradually evolving to acknowledge the deeper motivational underpinnings of this behaviour, leading to greater social acceptance of stimming (see Sesame Street - Meet Julia). Historically, stimming has been associated with various developmental and psychological disorders and as such has been seen as a symptom requiring treatment. With research finding considerable associations between low acceptance of stimming and mental illness, one must consider how the reduction (versus encouragement) of stimming behaviour can significantly impact wellbeing.

It is evident that although emotion regulation, perceived control and the self provide independent explanations for stimming motivation, it is likely that they interact to create unique combinations for personal and individualised motivations. Additionally, what might motivate stimming in one context may change in another context; meaning, that at one time stimming may be used for emotion regulation but later the same stimming behaviour may be used for self-verification. The focus of future interventions should concentrate on ways in which we can support individuals, foster the use of stimming in adaptive ways, and in turn prevent unnecessary psychological distress and mental illness.

While the suggested stimming motivations presented in this chapter are yet to have comprehensive and specific empirical support, there is an ethical obligation for research to continue in this area. Based on sound theoretical framework and the critical application of these theories, researchers have presented strong arguments for the existence of intrinsic stimming motivations which may have significant implications for the current approaches to stimming behaviour management.

See also

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References

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Barrett, S., Uljarević, M., Baker, E., Richdale, A., Jones, C., & Leekam, S. (2015). The adult repetitive behaviours questionnaire-2 (RBQ-2A): A self-report measure of restricted and repetitive behaviours. Journal of Autism & Developmental Disorders, 45(11), 3680-3692. https://doi.org/10.1007/s10803-015-2514-6

Berlyne, D. (1960). Conflict, arousal, and curiosity. New York, NY: McGraw-Hill Book Company.

Brehm, S., & Brehm, J. (1981). Psychological reactance: A theory of freedom and control. New York, NY: Academic Press.

Cage, E., Di Monaco, J., & Newell, V. (2018). Experiences of autism acceptance and mental health in autistic adults. Journal of Autism & Developmental Disorders, 48(2), 473-484. https://doi.org/10.1007/s10803-017-3342-7

Declerck, C., Boone, C., & De Brabander, B. (2006). On feeling in control: A biological theory for individual differences in control perception. Brain and Cognition, 62(2), 143-176. https://doi.org/10.1016/j.bandc.2006.04.004

Joosten, A., Bundy, A., & Einfeld, S. (2012). Context influences the motivation for stereotypic and repetitive behaviour in children diagnosed with intellectual disability with and without autism. Journal of Applied Research in Intellectual Disabilities, 25(3), 262-271. https://doi.org/10.1111/j.1468-3148.2011.00663.x

Kapp, S. Steward, R., Crane, L., Elliott, D., Elphick, C., Pellicano, E., & Russell, G. (2019). ‘People should be allowed to do what they like’: Autistic adults’ views and experiences of stimming. Autism, 23(7), 1782-1792. https://doi.org/10.1177/1362361319829628

Langen, M., Durston, S., Kas, M., van Engeland, H., & Staal, W. (2011). The neurobiology of repetitive behavior: …and men. Neuroscience & Biobehavioral Reviews, 35(3), 356-365. https://doi.org/10.1016/j.neubiorev.2010.02.005

Leekam, S., Tandos, J., McConachie, H., Meins, E., Parkinson, K., Wright, C., . . . Couteur, A. (2007). Repetitive behaviours in typically developing 2-year-olds. Journal of Child Psychology & Psychiatry, 48(11), 1131-1138. https://doi.org/10.1111/j.1469-7610.2007.01778.x

Lewis, M., Baumeister, A., & Mailman, R. (1987). A neurobiological alternative to the perceptual reinforcement hypothesis of stereotyped behavior: A commentary on “self-stimulatory behavior and perceptual reinforcement”. Journal of Applied Behavior Analysis, 20(3), 253-258. https://doi.org/10.1901/jaba.1987.20-253

Lewis, M., Bodfish, J. Mcilvane, W., Bristol, M., & Alexander, D. (1998). Repetitive behavior disorders in autism. Mental Retardation and Developmental Disabilities Research Reviews, 4(2), 80-89. https://doi.org/10.1002/(sici)1098-2779(1998)4:2

Lovaas, I., Newsom, C., & Hickman, C. (1987). Self-stimulatory behavior and perceptual reinforcement. Journal of Applied Behavior Analysis, 20(1), 45-68. https://doi.org/10.1901/jaba.1987.20-45

Mays, N., Beal-Alvarez, J., & Jolivette, K. (2011). Using movement-based sensory interventions to address self-stimulatory behaviors in students with autism. Teaching Exceptional Children, 43(6), 46-52. https://doi.org/10.1177/004005991104300605

Perrykkad, K., & Hohwy, J. (in press-a). Modelling me, modelling you: The autistic self. Review Journal of Autism and Developmental Disorders, 1–31. https://doi.org/10.1007/s40489-019-00173-y

Perrykkad, K., & Hohwy, J. (2020). Fidgeting as self-evidencing: A predictive processing account of non-goal-directed action. New Ideas in Psychology, 56. Advance online publication. https://doi.org/10.1016/j.newideapsych.2019.100750

Petrus, C., Adamson, S., Block, L., Einarson, S., Sharifnejad, M., & Harris, S. (2008). Effects of exercise interventions on stereotypic behaviours in children with autism spectrum disorder. Physiotherapy Canada. Physiotherapie Canada, 60(2), 134-145. https://doi.org/10.3138/physio.60.2.134

Ravizza, S., Solomon, M., Ivry, R., & Carter, C. (2013). Restricted and repetitive behaviors in autism spectrum disorders: the relationship of attention and motor deficits. Development and psychopathology, 25(3), 773-784. https://doi.org/10.1017/S0954579413000163

Samson, A., Hardan, A., Podell, R., Phillips, J., & Gross, J. (2015). Emotion regulation in children and adolescents with autism spectrum disorder. Autism Research, 8(1), 9-18. https://doi.org/10.1002/aur.1387

Shafritz, K., Dichter, G., Baranek, G., & Belger, A. (2008). The neural circuitry mediating shifts in behavioral response and cognitive set in autism. Biological Psychiatry, 63(10), 974-980. https://doi.org/10.1016/j.biopsych.2007.06.028

Sinha, P., Kjelgaard, M., Gandhi, T., Tsourides, K., Cardinaux, A., Pantazis, D., . . . Held, R. (2014). Autism as a disorder of prediction. Proceedings of the National Academy of Sciences, 111(42), 15220-15225. https://doi.org/10.1073/pnas.1416797111

Steindl, C., Jonas, E., Sittenthaler, S., Traut-Mattausch, E., & Greenberg, J. (2015). Understanding psychological reactance: New developments and findings. Zeitschrift fur Psychologie, 223(4), 205-214. https://doi.org/10.1027/2151-2604/a000222

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