CHAPTER 6
Exploring the Relationship of Selective Mutism to Autism Spectrum Disorder
A child is seen standing alone in the playground looking worried and rather sad. S/he is said to be socially isolated, wary of changes or new things, rather a perfectionist and talking very little. School staff are concerned. Could s/he have an autism spectrum disorder, or Selective Mutism (SM), or both, or some other anxiety or communication disorder? In this chapter we will consider common misconceptions and misdiagnoses of SM, the similarities and differences between SM and autism spectrum disorders (ASD), and look at how common it is for these two to co-exist. We will discuss the issues that may arise in diagnosis of the two conditions, and guidelines and pitfalls of assessment. Suggestions will be made for management of SM if a child or young person has the dual diagnosis.
Common misconceptions and misdiagnoses
There is no doubt that people still do not fully understand SM, and they may either confuse it with or miss other diagnoses. Many people have never come across SM in spite of developments in the past ten to fifteen years, increased coverage in the media and in the literature of professionals, and the splendid work done in various countries by voluntary organizations such as SMIRA and the Selective Mutism Foundation in the USA. In some ways it is a hidden difficulty and usually temporary, and it may seem perplexing to some since the mutism does not occur in every setting with all people.
Diagnosis of childhood disorders is a complex and subtle business. Issues and misunderstandings may arise from inadequate experience or knowledge about the field of differential diagnosis, and this can apply to educational and medical professionals and therapists as well as the general public. Some people do not understand exactly what features are necessary for the diagnosis of a certain condition, or that many conditions have overlapping symptoms, or that a child or young person may have more than one diagnosis. Regrettably, when a child may possibly have more than one diagnosis, there can sometimes be a blinkered attitude to assessment, a failure to look broadly and deeply enough at all the symptoms or to see the child or young person as a whole.
So what are the most common misconceptions and misdiagnoses and the ensuing problems that can occur? Up to 20 years ago SM was called Elective Mutism and generally thought of as wilful and deliberate refusal to talk, leading to an assumption – if not a diagnosis – of a behaviour disorder. The child’s silence received a lot of attention, pressure was put on the child to talk, unrealistic rewards or bribes were offered and sometimes punishment or penalties might have been exacted if the child did not progress. Of course this can still happen. However, as a result of more accurate and widespread publicity and research, more people now understand that it is an anxiety disorder, and its new classification as such in the Diagnostic and Statistical Manual, 5th edition, DSM-5 (APA 2013) is a great help. However, some people may recognize it as an anxiety condition but continue to misunderstand the cause. Suspecting that the SM is a result of specific trauma or abuse or solely due to an attachment disorder, they may adopt a rather blaming attitude and may unhelpfully refer the child in the first instance for a form of psychotherapy.
Other difficulties may occur with possible speech, language and communication disorders or problems with dual language or ESOL (English for Speakers of Other Languages). Assumptions can be made that these are the reasons for the lack of talking. The SM is then overlooked, rather than advice sought from a speech and language therapist or an ESOL specialist as to the existence and relationship of SM with one of these problems.
Lastly there are misconceptions and misdiagnoses around SM and ASD. Most commonly questions are asked as to whether children (before or after a diagnosis of SM) who do not communicate or make eye-contact may have ASD; or whether older children whose SM has not resolved as expected may have ASD.
Features of ASD and SM
In considering the issues that arise around the diagnosis of both SM and ASD, and the reasons for possible confusions, it is necessary to be clear about the key features of the two conditions. We start by looking at summaries of the recently published DSM-5 and note the modifications of the classification of both from the previous edition. Many readers, and of course those carrying out assessment, are advised to look at the exact words that appear in DSM-5.
Autism Spectrum Disorder can be recognized by the early onset of features in two areas:
1.Persistent deficits in social communication and social interaction across multiple contexts, incorporating the two areas previously described in DSM-IV as social impairment/reciprocal interaction and communication impairment. These deficits are divided into three sub-groups. First, deficits in social-emotional reciprocity, which covers: abnormal social approach and failure of normal back-and-forth conversation; reduced sharing of interests, emotions or affect; and failure to initiate or respond to social interactions. The second sub-group is deficits in non-verbal communication, covering eye contact, body language, gestures and facial expressions. Third, we have deficits in developing, maintaining and understanding relationships, looking at difficulties adjusting behaviour to suit various social contexts, sharing imaginative play or making friends, and absence of interest in peers.
2.Restricted, repetitive patterns of behaviour, interests or activities, previously known as restricted and repetitive activities and interests. There are four sub-groups of symptoms in this area. One relates to stereotyped or repetitive motor movements, use of objects or speech; another to insistence on sameness, routines, or ritualized patterns of verbal or non-verbal behaviour; another to abnormally intense and highly restricted, fixated interests; and the fourth to hyper- or hypo-reactivity to or unusual interest in sensory input.
All three social communication and social interaction deficits must be evident, whereas only two of the four restricted, repetitive patterns of behaviour, interests or activities need to be present. An interesting change to note since DSM-IV is that the presence of the symptoms is now evaluated by three specific severity levels based on the level of support required, with examples given as to what this means in practice.
ASD is now a single diagnostic category so, following research into the inconsistency of distinctions among the various ASD subtypes, Asperger Syndrome is not included in DSM-5, nor are the other two less well known sub-diagnoses Pervasive Developmental Disorder Not Otherwise Specified and Disintegrative Disorder.
Selective Mutism is for the first time classified in DSM-5 under Anxiety Disorders, which is a clear statement and should be a great help when parents and others are trying to explain about the fundamental nature of the disorder. The wording of the five diagnostic criteria has not changed in the new edition. The main feature remains the consistent failure to speak in specific social situations despite speaking in other situations; and the second notes the effect of this on educational or occupational achievement or with social communication. SM can be diagnosed after a month, provided this is not the first month of school. The last two features state that the lack of knowledge or comfort with the required spoken language, or a disorder of communication such as stammering or a condition such as ASD, are not the cause and do not explain the mutism. Put another way, SM is more than the silences that all children with speech and language impairment, stammering or ASD may exhibit at times, although it is important to remember that these other diagnoses may also be present, as is discussed further in the next section.
Co-existence of ASD with SM
Co-existence (or co-morbidity, which is the medical term) is common in the field of developmental disorders, so it is not surprising that some children and young people with SM have also been found to have additional difficulties and diagnoses. In The Selective Mutism Resource Manual (2001), Johnson and Wintgens attempted to break down the diagnostic categories of SM into four sub-groups. Box 6.1 shows the three categories they currently use based on more recent experience. Using this framework, children and young people with an additional diagnosis of ASD would come under the category of ‘Complex Selective Mutism’.
BOX 6.1 JOHNSON AND WINTGENS’ DIAGNOSTIC CATEGORIES OF SELECTIVE MUTISM
•Pure Selective Mutism, where children have no additional disorders. It may be termed ‘low or high profile’ depending on whether the presentation is obvious.
•Selective Mutism, plus speech or language impairment or ESOL (English as a Second or Other Language) problems.
•Complex Selective Mutism – SM plus other diagnoses such as ASD or SAD (Social Anxiety Disorder), or significant major concerns (medical, environmental or emotional).
One of the most comprehensive studies of co-morbidity that mentions ASD (in the form of Asperger Syndrome) is that of Kristensen (2000), who looked at 54 children and young people with SM matched by 54 controls. She found 69 per cent with one or more additional developmental disorders, whereas this occurred in only 13 per cent of the controls. Of the 69 per cent, 7 per cent were said to have Asperger Syndrome; and 74 per cent had additional anxiety disorders compared with 7 per cent in the control group. Most strikingly, 46 per cent of those in the SM group had both a developmental disorder and an anxiety disorder, which only applied to 1 per cent of the control group.
Could it be more than SM?
In the author’s experience, questions of possible dual diagnosis mostly arise about whether a child with SM may also have ASD or some other disorder rather than the reverse. This is probably because initial or superficial diagnosis of SM is not difficult and can generally be made early. Essentially, the child or young person will consistently speak freely to some people in some situations (usually to close family members at home) and not to others in less familiar situations. Many who work with and observe this in pre-school or school-age children will recognize it as SM. It may help at this stage to have the diagnosis confirmed by someone with more experience of SM, but it is not essential to have an ‘official’ diagnosis of SM before putting some strategies in place to help the child.
Clearly, there are some children whose SM does not resolve as expected; they do not make much progress with talking fully and freely to more people or they appear to have reached a plateau. Rather than immediately looking for a possible second diagnosis, it is wise to consider a more in-depth assessment of the SM and to look thoroughly at why the SM interventions may not be working. The advanced training in SM at University College London addresses common practices that prevent or hinder progress, the first of which relates to inadequate assessment of the SM. Quite often it is found that unexplored factors at home or school are reinforcing the child’s mutism or raising her anxiety, or that cultural or personal inhibitions may be present. With some children there is not sufficient appropriate intervention, or it is not broken into small enough steps or carried out frequently enough. These issues all need to be addressed in the first instance. Of course, the child may indeed have additional problems such as ASD, an attachment disorder or other anxiety or communication disorder, and it would be prudent at this stage to consider all these options. The school psychologist or speech and language therapist should look at a broader and deeper assessment of the concerns, possibly using the Parental and School Interview Forms from The Selective Mutism Resource Manual (Johnson and Wintgens 2001). This may then indicate the need for further referral and which specialist or team might best be able to undertake appropriate assessment and diagnosis.
Possible similar symptoms in SM and ASD
There is no doubt that children and young people with SM appear to present with some similar symptoms to those with ASD, partly because some anxiety-based behaviours can look very much like autism. It may be that this can lead to misunderstandings or misdiagnoses. However, a more detailed look at the symptoms is likely to show that they occur for different reasons or they manifest in somewhat different ways. Let us look at the various features and consider why they may arise and whether they really are similar in the two conditions.
Reluctance to communicate
At first glance in a situation such as school, children with SM and those with ASD both seem reluctant to communicate. On closer inspection we see that children with SM have a specific pattern of non-communication which is person- or situation-related, but have normal reciprocal conversation with people in their comfort zone. In contrast, children with ASD often don’t talk much to close family either. They don’t do social chit-chat because they don’t see the point of it and need to be really interested in something before it stimulates their desire to talk. Their reluctance to communicate is topic-related rather than person-related.
Wariness of change or things that are new or different
Children with either of the two conditions do not cope well with the unexpected. For example, in school something like a change in the timetable or a different teacher may cause them to be upset as they prefer structure and certainty. For those with SM this is triggered by their anxiety: there may be new people who don’t understand about SM or they may be expected to speak more than they are able. Sufferers of ASD, however, prefer things to be the same because they are confused by change; new things don’t make sense to them and disrupt the safe routine that they need.
Social isolation
If observed in unfamiliar and group situations, someone with SM may appear socially isolated because of the fear of having to talk, but once the child is within her comfort zone she will not appear isolated. An example of this can be seen in the Silent Children DVD (2004, available from SMIRA) when Rachel is at home at a birthday party for her grandmother. In contrast, those with ASD will appear isolated or socially different to their peers even with familiar people in familiar settings, because of their social communication deficits.
Problems with social skills
There is no doubt that children with SM lack experience of developing social skills in the usual way. They cannot manage to use everyday greetings and terms of politeness with unfamiliar people. They cannot experience talking and then having to keep quiet at certain times in nursery or practise sharing or working in groups in school. For these reasons it is sometimes necessary, once their SM has resolved, for them to have some training in assertiveness or social skills, or informal help in this area from parents and school. In contrast, a child with ASD, despite social skills training through which he might learn new skills, is always likely to have difficulty in this area. This is part of the condition, the reason he has an ASD diagnosis.
Desire to get things right
Perfectionism is a trait that has been noted in children with either SM or ASD. The child with SM is cautious, restrained and tends not to take risks. This seems to arise out of self-consciousness, because of anxiety about drawing attention to themselves or being criticized. In contrast, the child with ASD is not self-conscious but his actions are governed by rigidity, concrete thinking and inappropriate attention to detail.
Differences in eye contact
The quality and quantity of appropriate eye contact is noticeable in children with either of these two conditions. Because of their anxiety and the wish to avoid talking, children with SM are often seen to be wary and watchful, they may appear to stare in rather a frozen way, or they may look down. In a child with ASD the quality of eye contact is unusual during communication: most often there is a lack of eye contact when speaking or listening, or the eyes are not used for referencing, that is, not directed towards what the child is talking about and back to check that the listener is following.
Differences in body posture
Again, the differences in body posture are displayed in different ways in the two conditions. The child with SM, when out of his/her comfort zone, will appear tense, frozen or stiff, like a rabbit trapped in the headlights. Tension may be manifest in raised shoulders or turning the whole of the upper body rather than just turning the head. Sometimes body posture is so extreme or bizarre that children have been referred to a physiotherapist. Body posture in someone with ASD looks different: it occurs in the form of mannerisms or stereotyped body movements. As with social isolation, children with SM have normal eye contact and body posture once they are in their comfort zone, in contrast to children with ASD.
Difficulty with open questions
A child with SM is anxious about talking with unfamiliar people and has to gradually build up competence and confidence in small steps. It is easier if this is practised in tasks where there is a low communication load – where speech is automatic or rote-learnt, simple and concrete or a short answer to a closed question, as opposed to tasks with a high communication load where the child has to express personal, uncertain or controversial opinions. In contrast, the child with ASD has intrinsic problems with abstract language, and is rigid and concrete in his thinking; these are the reasons why he/she copes better with closed questions or when given limited choices.
Guidelines and pitfalls in the assessment of ASD in a child with SM
An assessment for the right reasons
An assessment of possible ASD is important and helpful for several reasons. If confirmed, it may help people understand the pattern of behaviours the child is presenting; it may explain the additional concerns parents have sometimes had for a long while, and the ‘label’ may point the family and school towards more appropriate strategies than have been offered so far. Sometimes it may affect the level of support the child receives or even his/her educational placement. The reverse is also true. If a diagnosis of ASD is not confirmed, this can also put an end to the mis-labelling of the child. However some may be disappointed that there is no label, no fresh start and possibly no increased help. Indeed, regrettably, it has been known for people to recommend or seek an ASD diagnosis thinking that they can access more help for the child than they have been offered with ‘only a diagnosis of SM’.
General guidelines and comments
Let us assume that a decision has been made, for the right reasons, to consider whether the child or young person may have ASD. The suggestions below apply equally to children being assessed for ASD as a first diagnosis when in fact they may well have SM but this hasn’t been identified or a second diagnosis to see whether the child or young person with SM may also have ASD. Where and how this is done will obviously depend on local services, but below we will consider guidelines of what makes for a thorough assessment. Questions need to be asked about the contents of the assessment, the assessors’ experience and understanding of SM, and the modifications that will need to be made when assessing ASD in a child with possible or identified SM. This is important since SM is rarely seen in specialist paediatric or mental health clinics. In addition, the ASD may not be very obvious or it would have been picked up earlier.
Involvement of several professionals
It is good practice when assessing a child with a possible ASD for more than one professional to be involved. The professionals need experience and expertise in developmental, behavioural and communication disorders, so most usually it will be a paediatrician or child psychiatrist, plus psychologist and/or speech and language therapist. The assessment may be done by a team in a Children’s Centre, Developmental Paediatric or Child and Adolescent Mental Health setting, and they may hold a special clinic for the purpose.
A typical assessment
In order to decide whether a child may have ASD, the assessor needs to get a detailed history of the child’s development, behaviour and experiences, as well as a picture of the child’s current presentation. This is achieved in two ways: it is based on information from those who know him well, and also from meeting, observing and communicating with the child himself. An interview with the parents or carers may be the sole method of gathering the information, but questionnaires may also be used, and there may be reports from others who know the child well, such as school staff.
Specific assessment measures
The Autism Diagnostic Interview – Revised (ADI-R) (Rutter et al. 2003) is a tool that is commonly used to gather information from parents or carers about children over the age of two years. The ADI-R is a standardized semi-structured interview that is scored. When used to assess whether a child who is mute with strangers may have ASD, it has the advantage that the parent or carer can comment on the child’s behaviour with familiar people in a familiar, comfortable setting. Allowances should be made for the limited social experiences of the child with SM, which will restrict responses and therefore the score of certain items (e.g. response to the approaches of other children; appropriateness of social responses).
The most popular tool for the direct assessment of the child is the Autism Diagnostic Observation Schedule (ADOS) (Lord et al. 2000). Standardized activities and situations are presented to elicit communication, social interaction and imaginative play. The assessor looks out for any social communication deficits, fixated interests and repetitive behaviours which, if sufficiently severe when scored, would indicate a diagnosis of ASD. There are obvious drawbacks should the ADOS be used for a child already diagnosed or with a possible diagnosis of SM. Unable to communicate freely with an unfamiliar adult in an unfamiliar setting, the child would be likely to achieve a poor score and a possible misdiagnosis. It would be important to establish whether the parent felt the child’s performance accurately portrayed his/her general interaction style, or if it was only typical of how he/she behaves with strangers.
Alternative or additional assessment tools
Given the difficulties of direct assessment of the child who is mute with strangers, the assessor would need to look for different ways to glean relevant information. If the child felt comfortable enough in a clinic room with close family members, observation might be possible through a one-way viewing mirror. Equally, a DVD of the child at home could be immensely helpful. In either case more weight might need to be given to the detailed parental interview, and to ensure that this information is supplemented by additional questionnaires or reports from any with whom the child communicates freely.
Probably the most important factor that needs accurate assessment when considering a possible ASD diagnosis is the question as to whether the child has empathy. Known previously as theory of mind, Simon Baron-Cohen (2003) describes it as ‘the drive to identify another person’s emotions and thoughts, and to respond to them with an appropriate emotion…in order to connect or resonate with them emotionally.’ Baron-Cohen states that ‘ASD is primarily an empathy disorder’. So any measures or information about the presence or absence of empathy in a child, when with familiar people to whom she speaks comfortably, would be valuable.
Management of a child with SM and ASD (SM+ASD)
Keen et al. (2008) discovered that early identification and intervention are universally acknowledged as crucial for good management of SM. It follows that if any child has SM, regardless of any other diagnosis, it is still always important to address the SM as soon as possible. Yet sometimes people seem distracted by an additional diagnosis. For example, they might hasten to focus on teaching language skills to a child with additional language impairment, or social skills to a child who also has ASD, putting aside and sometimes contradicting intervention for SM. Consequently, the SM becomes more entrenched.
So, even if the child has SM+ASD, the SM must be addressed using methods that are known to be effective. The key ones are set out in Box 6.2 (see following page) and discussed with relevance to the dual diagnosis.
BOX 6.2 EFFECTIVE MANAGEMENT OF SELECTIVE MUTISM
1.Early identification and intervention.
2.Education of all involved with the child about the nature of SM to ensure thorough understanding of the condition and united home/school team work.
3.Identification and adaptations of any factors that maintain the problem in order to create the right environment at home and school.
4.Acknowledgement and discussion of the difficulty with the child.
5.Introduction of informal small-step targets.
6.For older children, a specific coordinated behavioural programme of desensitization and graded exposure, such as stimulus fading (the ‘sliding-in’ technique).
7.Additional interventions, such as social skills, Cognitive Behaviour Therapy (CBT), or occasionally medication for older children and young people who present a more complex picture with co-morbid diagnoses.
In many ways the SM intervention need not be very different with the child with SM+ASD, provided that those involved have some understanding of ASD and knowledge of strategies that are helpful for the management of ASD. Nothing needs to change with regard to the first three items: early identification and intervention; education of all involved; and identification and adaptations of maintaining factors. When working directly with the child (items 4–6 in Box 6.2: acknowledgement and discussion of the difficulty; introducing informal small-step targets; and explaining a specific programme), additional visual support will be necessary to compensate for difficulties with abstract language and emotions. The small guide Can I tell you about Selective Mutism? (Johnson and Wintgens 2012), with its clear and simple information and line drawings, may be useful, and there is another in the series that describes ASD (Welton 2004). Stick men and simple line drawings or cartoons are helpful, as are facial expressions (graded smiling to sad faces) for a self-rated anxiety scale.
There are some other important considerations. Careful attention should be paid to finding suitable motivators for the SM+ASD child given their tendency not to be interested in more usual social rewards or reinforcers. Parents should have realistic expectations about the goals of SM therapy. With ASD there is a general reluctance to communicate, and the child is still likely to be non-communicative at times because they don’t appreciate the need to be polite, or have natural curiosity in other people’s affairs. In addition, all those involved with the child with SM+ASD will particularly need to be consistent and prepared for a long-term commitment to intervention.
Some autistic characteristics may impede progress with a specific SM programme, particularly sensory issues such as intolerance of noise or physical approaches. Likewise, the inability to use language outside the ‘here-and-now’ can make it hard to offer reassurance and hope when the child fails to progress or has a setback. However, it is possible to find ways round these factors, and once a specific co-ordinated behavioural programme of desensitization and graded exposure (such as stimulus fading, the ‘sliding-in’ technique) has been started, it is not uncommon to find that the rule-bound nature of a child with ASD is an advantage. The structure that the programme provides and the concrete rewards for each small step while progress is achieved give a feeling of safety and confidence. Soon, clear signs of an increased ability to speak out with more people in more situations can be observed.