**3. Qualitative impairments in communication**

Qualitative impairments in communication form the second criterion that is defined in DSM-IV-TR, and this can refer to the use of language but also to problems in make belief or imitative play. When it comes to language one can find a lack of or delay in language, but also use of repetitive or idiosyncratic language. Autistic people may also find it troubling to initiate and maintain a conversation with others [2].

#### **3.1. Making conversation**

action) or what someone would want to eat (after showing them pictures of food they liked). It appeared that the deaf children and hearing children performed equally well on the inten‐ tion tasks, but the hearing children outperformed the deaf on false belief tasks and on the desire tasks [43].This study indicates that deaf children may possess some abilities related to a theory of mind. It should be noted, however, that this study only included children with a CI. These children thus had some hearing abilities, though different from hearing children. The study did not include a group that was completely deaf and so conclusions about com‐

When children are completely deaf there is, however, still the possibility that, as seen in the visually impaired group, testing methods are not adequate for them. Peterson and Siegal [40] tried to make their intentions more clear in their false belief questions. They reasoned that someone with limited experience in conversation might expect that the experimenter just wants them to tell the location of Sally's marble, when they ask "Where will Sally look for her marble?" For this reason they altered the question to "Where will Sally first look for her marble?" By adding the word "first" they more clearly imply that they are looking for what sally thinks instead of where the marble really is. This slight alteration improved the deaf children's performance slightly, but not enough to overcome differences in ToM devel‐ opment [40] as the different tasks in the study by Ketalaar et al. [43] did. Peterson and Siegal only investigated false belief, though, whereas Ketelaar et al. adressesd other aspects of ToM and tested children with a CI who do have some hearing abilities, instead of children who are completely unable to hear. The question still remains whether a more appropriate meth‐ odology for deaf children could increase their scores on conventional ToM tasks and more

Finally, people with intellectual disabilities often show ToM impairments as well. Typical developing children start to solve ToM tasks around the age of four to five years of age. A general characteristic of people with intellectual disabilities is that they have mental ages not corresponding to their chronological ages. If mental age is below five, which is the case in profoundly and severely intellectually disabled people, and sometimes also in moderately intellectually impaired people they will probably fail ToM tasks irrespective of their chrono‐ logical age [44]. Interpretations of ToM tasks should be done cautiously, when intellectually disabled people likely fail this task unrelated to the presence of ASD, to prevent unnecessa‐

Qualitative impairments in communication form the second criterion that is defined in DSM-IV-TR, and this can refer to the use of language but also to problems in make belief or imitative play. When it comes to language one can find a lack of or delay in language, but also use of repetitive or idiosyncratic language. Autistic people may also find it troubling to

pletely deaf children cannot be drawn.

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research has to be done in order to clarify this.

**3. Qualitative impairments in communication**

initiate and maintain a conversation with others [2].

ry suspicion of ASD.

Language is something people use for communication, and so the willingness to communi‐ cate is related to their use of language [19].Despite possible technical problems in language the low desire for communication is one of the aspects of ASD that is mentioned in the DSM-IV-TR, that is not only problems in initiating and maintaining a conversation with oth‐ ers but also a lack of an internal willingness or desire to communicate [2]. If people with ASD are simply uninterested in communication, they will not put effort in initiating a social conversation spontaneously. This lack in willingness to communicate also contributes to the language problems found in ASD.

Initiating and maintaining a conversation can be difficult for people with sensory and intel‐ lectual disabilities too. The presence of others may go unnoticed for people with visual im‐ pairments, and communicative signs may be missed because of blindness or deafness. It has been found that deaf children communicate less with their hearing parents because of their poor skills in spoken language and their parents poor sign language skills [41]. In people with intellectual disabilities conversational skills may be worse than expected based on their chronological age, moreover, their initiations to communicate may be different, inadequate or even awkward.

Even though all of these impaired groups may show impaired conversation making skills, there are differences between autistic and non-autistic people. An example derived from a deaf population shows that despite other problems in the field of communication, such as monitoring a conversation and pragmatic use of language, non-autistic deaf children are not different from their hearing peers in initiating and maintaining a conversation [22]. But even though deaf children without ASD don't seem to have problems in initiating and maintain‐ ing a conversation, they still differ from their hearing peers in pragmatics and monitoring, hampering their conversational skills nevertheless. On the contrary, the impaired conversa‐ tional skills in autistic people lie in the area of the initiation and maintenance of a conversa‐ tion [2]. It also appeared that one of the areas in which the autistic and non-autistic children with deafblindness and profound intellectual disability differed significantly from each oth‐ er was the openness and willingness to take initiatives for contact [7]. It is evident that con‐ versation looks different for people with sensory or intellectual impairments versus people without impairments, and conversation skills are hampered by their lack of sensory and in‐ tellectual abilities. The difference with autistic people shows itself in the interest for this con‐ tact. Non-autistic sensory and/or intellectually impaired people still look for opportunities to make this contact or respond to other people's efforts to make contact, while people with autism lack the interest for this contact.

#### **3.2. Language**

Besides a lower interest in communication than people without ASD, people with ASD show some technical language impairments as well. Some autistic people do not speak at all and in others the development of language can be seriously delayed or altered [19]. Further‐ more, it appears that joint attention and imitation behaviours, which are known to be im‐ paired in ASD, can predict language abilities [27], which raises the question whether language is directly or indirectly related to ASD. In addition, ToM can be involved as well, one needs to know that one can influence others with their language and how to do so. Typ‐ ical ASD language problems include direct or delayed echolalia, reversal of pronouns and lack of understanding of emotional meaning in language. People often describe it as 'robotlike' [45]. People with ASD often interpret the meaning of words literally. The literal mean‐ ing of a word does not change over contexts, but the figural meaning does. This is especially vivid in jokes, metaphors and irony. This may also be due to the previously mentioned problems in ToM. Being unable to understand what people mean, people with ASD inter‐ pret the words incorrectly [19]. A review about language and communication in ASD con‐ firmed this idea by concluding that the language and communication problems are caused by processing problems when interacting with other people [46].

old who often repeated her mother's words to learn the names of objects, but also to practice these words [50]. It can therefore be expected that a person with a mental age below two years of age to still show signs of echolalia. These examples consist of people with typically developing vision, but blind children use echolalia even more than typically developing children. In part echolalia serves as a means to stay in contact with people that cannot be seen, but it is also suggested that blind children practice their language by using echolalic speech. In this way they try to get a grip on the meaning of words in the absence of vision [30]. Extra practicing of words and phrases also results in more imitations and use of rou‐ tines in speech. In the blind, one will also find egocentric speech and reversal of personal pronouns(I, you, he etc.), and improper use of deictic terms (e.g. here, there) which could be mistaken for autistic language, because of its atypical nature. Reversal of personal pronouns, which is found in about a third of the speech of blind children and egocentric speech may be caused by a lack of ToM, resulting in these impairments [12]. However, a logical explanation can also be based on the visual impairment. The direction of speech and who is speaking to whom determines which personal pronoun is used. Absence of vision makes it difficult to understand that the "I" who is speaking about the self is suddenly referred to as "you" by a person who became the "I" instead. 'Here' and 'there' are relative terms depending on ones spatial position. Without sight it is hard to adopt an allocentric position, most blind people use an egocentric position in processing spatial information. For instance, in way finding one cannot use landmark information to guide people who are blind, because they cannot see these landmarks. Instead one has to give route information related to the blind person's

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Finally, imitative and make-belief play are impaired in people with ASD according to the DSM-IV-TR. People with intellectually disabilities normally show delays or absence of imitation too. In one study, the experimenters showed intellectually disabled partici‐ pants an action that could be done with an object, afterwards they asked the participants what could be done with the object. All participants with intellectual disabilities had trouble recalling what could be done with the object. Participants with intellectual disa‐

Symbolic play can be troubled in people with intellectual disabilities as well. Wing and col‐ leagues [52] showed that even though only two people of their sample of intellectually disa‐ bled people showed the full autistic syndrome, more than half of their participants showed problems in symbolic play. These problems were either characterized as stereotyped play that was a persevering repetitive copy of other's play or no symbolic play at all, but just re‐ petitive manipulations of a part of an object. Despite the fact that only two of their partici‐ pants had an ASD diagnosis, many showed autistic features. In the group that was able to show symbolic play (43 of 108 participants), only two participants had slight autistic fea‐ tures [52].This finding shows that many intellectual disabled people show impairments in symbolic or make-belief play, and this can therefore not be used as a differentiating charac‐

body position in space [30].

**3.3. Imitation and make-belief or symbolic play**

bility and ASD performed the worst [51].

teristic of ASD versus no ASD in this group.

People with intellectual disabilities show delays in language as well as atypical language skills that can easily be confused with ASD. A study about the language abilities of a group of autistic children showed that there was a relationship between language abilities and IQ [46]. This study was done on autistic people only, but it is a rather expectable finding, even within people without ASD. It makes sense that the language abilities of someone with an intellectual disability are delayed as compared to peers with the same chronological age. This may be confused with the language deficits found in ASD, when in fact they are due to their intellectual disability. For this reason, we should not immediately attribute language issues in people with intellectual disabilities to ASD.

Deaf and people with hearing disabilities often show delays in acquiring language, but can also show peculiar uses of words [4]. Even delays in developing sign language are found for this is often not fully learned until children go to a school for the deaf. Parents are not fluent signers and fail to teach children the full scope of signs they could learn from a signer that is fluent [41]. Atypical language development can also be found in the blind. Without seeing things to potentially talk about, language is centred around other experiences in the blind compared to sighted people [18]. Children with congenital visual impairment have been shown to have difficulties with the use of language for pragmatic and social purposes, while structural language (e.g. articulation, grammar, vocabulary) was good or even superior [47, 48]. This delay or odd language use can be confused with what is found in autistic individu‐ als. However, this language delay may be corrected if it is taught in the right way. It's im‐ portant to realise that when a child misses its vision, they need to get stimulation through the other senses which affects their understanding of the meaning of words [18].

Several language problems that are found in autistic individuals are also found in people with other impairments. A typical example is echolalia, which is also found in visually and intellectually impaired people [23]. Echolalia is the apparently useless repeating of words or phrases, either immediately after they were spoken or after some time. Even in typically de‐ veloping children, echolalia is sometimes used to learn language [20], so it's not surprising to find this in people with intellectual disabilities who may have a mental age comparable to when it is normal to use this type of speech. According to Schlesinger, it can be expected for a typically developing 20 month year old to repeat words to indicate more than one (e.g. "apple, apple" for "two apples") [49]. Another author described a child of 15 – 18 months old who often repeated her mother's words to learn the names of objects, but also to practice these words [50]. It can therefore be expected that a person with a mental age below two years of age to still show signs of echolalia. These examples consist of people with typically developing vision, but blind children use echolalia even more than typically developing children. In part echolalia serves as a means to stay in contact with people that cannot be seen, but it is also suggested that blind children practice their language by using echolalic speech. In this way they try to get a grip on the meaning of words in the absence of vision [30]. Extra practicing of words and phrases also results in more imitations and use of rou‐ tines in speech. In the blind, one will also find egocentric speech and reversal of personal pronouns(I, you, he etc.), and improper use of deictic terms (e.g. here, there) which could be mistaken for autistic language, because of its atypical nature. Reversal of personal pronouns, which is found in about a third of the speech of blind children and egocentric speech may be caused by a lack of ToM, resulting in these impairments [12]. However, a logical explanation can also be based on the visual impairment. The direction of speech and who is speaking to whom determines which personal pronoun is used. Absence of vision makes it difficult to understand that the "I" who is speaking about the self is suddenly referred to as "you" by a person who became the "I" instead. 'Here' and 'there' are relative terms depending on ones spatial position. Without sight it is hard to adopt an allocentric position, most blind people use an egocentric position in processing spatial information. For instance, in way finding one cannot use landmark information to guide people who are blind, because they cannot see these landmarks. Instead one has to give route information related to the blind person's body position in space [30].

#### **3.3. Imitation and make-belief or symbolic play**

language is directly or indirectly related to ASD. In addition, ToM can be involved as well, one needs to know that one can influence others with their language and how to do so. Typ‐ ical ASD language problems include direct or delayed echolalia, reversal of pronouns and lack of understanding of emotional meaning in language. People often describe it as 'robotlike' [45]. People with ASD often interpret the meaning of words literally. The literal mean‐ ing of a word does not change over contexts, but the figural meaning does. This is especially vivid in jokes, metaphors and irony. This may also be due to the previously mentioned problems in ToM. Being unable to understand what people mean, people with ASD inter‐ pret the words incorrectly [19]. A review about language and communication in ASD con‐ firmed this idea by concluding that the language and communication problems are caused

People with intellectual disabilities show delays in language as well as atypical language skills that can easily be confused with ASD. A study about the language abilities of a group of autistic children showed that there was a relationship between language abilities and IQ [46]. This study was done on autistic people only, but it is a rather expectable finding, even within people without ASD. It makes sense that the language abilities of someone with an intellectual disability are delayed as compared to peers with the same chronological age. This may be confused with the language deficits found in ASD, when in fact they are due to their intellectual disability. For this reason, we should not immediately attribute language

Deaf and people with hearing disabilities often show delays in acquiring language, but can also show peculiar uses of words [4]. Even delays in developing sign language are found for this is often not fully learned until children go to a school for the deaf. Parents are not fluent signers and fail to teach children the full scope of signs they could learn from a signer that is fluent [41]. Atypical language development can also be found in the blind. Without seeing things to potentially talk about, language is centred around other experiences in the blind compared to sighted people [18]. Children with congenital visual impairment have been shown to have difficulties with the use of language for pragmatic and social purposes, while structural language (e.g. articulation, grammar, vocabulary) was good or even superior [47, 48]. This delay or odd language use can be confused with what is found in autistic individu‐ als. However, this language delay may be corrected if it is taught in the right way. It's im‐ portant to realise that when a child misses its vision, they need to get stimulation through

the other senses which affects their understanding of the meaning of words [18].

Several language problems that are found in autistic individuals are also found in people with other impairments. A typical example is echolalia, which is also found in visually and intellectually impaired people [23]. Echolalia is the apparently useless repeating of words or phrases, either immediately after they were spoken or after some time. Even in typically de‐ veloping children, echolalia is sometimes used to learn language [20], so it's not surprising to find this in people with intellectual disabilities who may have a mental age comparable to when it is normal to use this type of speech. According to Schlesinger, it can be expected for a typically developing 20 month year old to repeat words to indicate more than one (e.g. "apple, apple" for "two apples") [49]. Another author described a child of 15 – 18 months

by processing problems when interacting with other people [46].

issues in people with intellectual disabilities to ASD.

488 Recent Advances in Autism Spectrum Disorders - Volume I

Finally, imitative and make-belief play are impaired in people with ASD according to the DSM-IV-TR. People with intellectually disabilities normally show delays or absence of imitation too. In one study, the experimenters showed intellectually disabled partici‐ pants an action that could be done with an object, afterwards they asked the participants what could be done with the object. All participants with intellectual disabilities had trouble recalling what could be done with the object. Participants with intellectual disa‐ bility and ASD performed the worst [51].

Symbolic play can be troubled in people with intellectual disabilities as well. Wing and col‐ leagues [52] showed that even though only two people of their sample of intellectually disa‐ bled people showed the full autistic syndrome, more than half of their participants showed problems in symbolic play. These problems were either characterized as stereotyped play that was a persevering repetitive copy of other's play or no symbolic play at all, but just re‐ petitive manipulations of a part of an object. Despite the fact that only two of their partici‐ pants had an ASD diagnosis, many showed autistic features. In the group that was able to show symbolic play (43 of 108 participants), only two participants had slight autistic fea‐ tures [52].This finding shows that many intellectual disabled people show impairments in symbolic or make-belief play, and this can therefore not be used as a differentiating charac‐ teristic of ASD versus no ASD in this group.

When these people with intellectual disabilities have an additional sensory impairment, problems in symbolic play and imitation can become more evident. It is reasonable to think that people with impaired vision or hearing have more difficulties in imitating because they are less able to perceive actions of others, than people without these impairments. Similarly, symbolic play can be affected. People have less modalities to perceive a toy with, and there‐ fore also see less ways in which they may use it. Combined with an intellectual impairment they can also have troubles in understanding the function the object is intended to have.

Repetitive and stereotyped use of objects is not only seen in autistic people but also in peo‐ ple with intellectual disabilities. In a study where 108 children with severe and profound mental disabilities were included less than two percent suffered from ASD. However, repet‐ itive routines and stereotyped play were found in 60 percent of this group with a mental age below 20 months [52]. Also in children who are blind strong interest in parts of objects and repetitive use of objects can be seen. Mainly this is the result of the blindness-specific con‐ straints on the use of play material that require visual-manual skills. Blind children, when playing alone, prefer toys and materials that produce distinctive tactile or auditory effects [53]. Toys are often articles of daily living and objects in their surroundings such as spoons, walls and furniture. Activities are often aimed at making noise [53, 54].This behaviour is thought to be a way of getting hold on the function of an object and in contrast to children

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Finally, autistic people show stereotyped movements with their own bodies or parts of their body. These are often thought to be self-stimulatory. Stereotyped movements can be per‐ formed with every body part but often involve the hands or walking [55, 56] and sometimes become self-injurious [57, 58]. These movements occur in other developmental disorders as well [55, 56], but are especially common in ASD. According to Kraijer self-stimulatory be‐ haviours are often caused by lack of stimulation from the environment [44]. In these situa‐ tions people use their own bodies to provide themselves with the stimulation they need at that moment. He adds to this that the amount of self-stimulatory behaviour and also intensi‐ ty and severity, that is whether it is self-injurious, is related to the level of functioning. The lower the functional level of the person, the more the self-stimulatory behaviour increases in

Stereotyped behaviours occur in people with visual impairments as well. Typical stereotyped behaviours in people who are blind are body rocking, head shaking, eye poking and hand flap‐ ping Because these behaviours often occur in the blind, they are sometimes referred to as blind‐ isms, [18, 20]. Actually this term is not entirely correct, because these stereotyped behaviours are not unique for people who are blind; mannerisms would be a better term. Body rocking and head movements, for instance, are typical examples of behaviours that can be seen in people with visual impairment, intellectual disabilities and ASD [18, 20, 24]. Stereotyped behaviours were seen in nearly all [59] and in all [60] blind children, but in children with visual impairment the prevalence is still 10-45% [59]. There also seems to be an age dependency in stereotyped be‐ haviours in blind children. In the first two years stereotyped behaviours increase in frequency to decline thereafter [61]. Stereotyped movements are also found in people with multiple disa‐ bilities. Heather Murdoch [62] suggests that stereotyped behaviours may be a part of normal motor development but that in people with multiple disabilities, these behaviours do not de‐ velop further. In a typically developing child, repetitive behaviours appear as well but develop into conscious movements later on, whereas in people with multiple disabilities they may re‐ main repetitive movements. Trying to stop these behaviours may hamper the development of

with ASD this behaviour can be relatively easily stopped or interrupted.

**4.2. Self Stimulation**

amount and severity [44].

other motor activities or communicative signs [62].

Lack of symbolic play was demonstrated to be related to abnormalities in language develop‐ ment that are typical of ASD, such as repetitive speech [52]. Similar to many of the impair‐ ments in ASD that were discussed, this too can be attributed to a lack of ToM. According to Brown et al. [12] ASD is characterized by problems in ToM, symbolic play, and context de‐ pendent language. Shared features of these three skills in childhood are: 1) there has to be a communication pattern between parent and child regarding feelings and thoughts; 2) one has to see and understand the direction of someone else's attitudes towards a shared world; and 3) feel inclined to identify oneself with this shared world. People with ASD have prob‐ lems with all three features. Children who are deaf encounter problems with the first fea‐ ture. They are offered less ToM related language. Children who are blind have trouble with the second feature and subsequently children who are deafblind have trouble with the first and second feature.
