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References. 1. Premack D, Woodruff G (1978) Does the chimpanzee have a theory of ... Journal of Autism and Developmental Disorders 29(4): 333-341. 17. ... 18. Silva TP, Silva AF, Tamanaha AC, Perissinoto J (2010) Atribuição de falsas.
BAOJ Pathology Arvigo MC, BAOJ Pathol 2017, 1: 1 1: 005

Research

Do Individuals with Down Syndrome Understand False-Belief Tasks? *

Arvigo MC

Speech pathologist, Unifesp/EPM, Brazil

Abstract Flaws in the Theory of Mind are commonly associated to the Autism Spectrum Disorder, since autistic individuals are characterized by social deficits and pragmatic disabilities. However, pragmatic inadequacies may also appear in pathologies in which intellectual disability co-occurs. Objective To observe the performance of children and adolescents with Down Syndrome in a false-belief task. Method

ToM to an individual only if he or she had the capacity to perceive and understand that his or her belief may conflict with reality, in other words, to be able to understand false-belief. De Villiers (2007) [3] points out that ToM is not only limited to false-belief and that other types of conceptual understanding can emerge in the typical child before of the 4-year-old. The author cites researches as Woodward (1999), which provides evidence that babies can interpret actions performed with human hands, when they address a given object, such as pointing, for example, but do not present the same reaction when the same action is done with inanimate objects, like a piece of wood.

26 children and adolescents, aged 6 to 13-year-old, and 5 adults, all with Down Syndrome responded to a false-belief task. Their results were compared to children with typical development aged 4 to 6-year-old.

However, most researchers [4,5,6] assume that ToM emerges in the typical child around 4-year-old, based on the results of Wimmer & Perner (1983).

Results

One of the leading researchers on Mind Theory in children with atypical development is Baron-Cohen. In one of his researches, Baron-Cohen and his collaborators (1985) [7] adapted an experiment by Wimmer & Perner (1983), converting it into the well known Sally-Ann task and applied it to autistic children in order to verify their abilities to understand other’s thinking and beliefs.

Subjects with Down Syndrome responded positively to the test.

Introduction The Theory of Mind (ToM) represents an important aspect of cognitive development and has received several definitions since its first mention by Premack & Woodruff (1978) [1] in his article entitled Does the chimpanzee have a Theory of Mind? In general, ToM is defined as an ability to attribute mental states, such as beliefs, desires, knowledge and thinking to others, and to predict their behavior per these attributions [2,3]. According to de Villiers (2007) [3], ToM is understood as a folk psychology used to suppose beliefs, feelings, intentions and desires to others and also to explain the behavior of the other, based on our own internal functioning. The first research about how children understands the beliefs of the other was held by Wimmer & Perner (1983), which consisted in stories where the main character had a false-belief which should be perceived by the child. Wimmer & Perner (1983) believed that it was possible to attribute BAOJ Pathol, an open access journal

The Theory of Mind in Down Syndrome

The results of this research showed that children with Autism Spectrum Disorder (ASD) present difficulties in understanding the other’s thinking and in predicting their behavior. The authors compared the results of autistic children and individuals with *Corresponding author: Arvigo MC, Speech pathologist, Unifesp/EPM, Brazil, E-mail: [email protected] Sub Date: March 30, 2017, Acc Date: April 7, 2017, Pub Date: April 10, 2017. Citation: Arvigo MC (2017) Do Individuals with Down Syndrome Understand False-Belief Tasks?. BAOJ Pathol 1: 005. Copyright: © 2017 Arvigo MC. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. Volume 1; Issue 1; 005

Citation: Arvigo MC (2017) Do Individuals with Down Syndrome Understand False-Belief Tasks?. BAOJ Pathol 1: 005.

Down Syndrome (DS) and typical 4-year-old children, and found that 80% of children with ASD failed the task, while 85% of typical children and 86% of DS children had good results on the same task. Many researchers have emerged [8,9,10,11]. Thus, it is assumed that autistic individuals present a deviation in the development of the capacity of meta-representation, that is, a failure in ToM. Baron-Cohen (1995) [12] calls this impairment in ToM as mindblindness, stating that such failure leads to deficits in social behavior and language. Since then, most researchers have assumed that difficulties related to ToM are unique to ASD.

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cognitive impairment could respond to the task and yet showed lower hit rates than typical children with the same mental age. The idea that individuals with DS have no problems with pragmatic skills, because they have behavior more sociable behavior than other developmental pathologies, apparently is not real. As we have seen, recent research has demonstrated that failures in ToM are not exclusive to individuals with ASD and that those with DS may present alterations in meta representation, albeit in a lighter gradation.

The Present Study

However, more recent studies [13,14,15] show that this deficit may not be unique to the autistic spectrum. Children with cognitive impairment, whether with syndromic origin, such as DS or Williams Syndrome, or with unidentified etiology, may present inadequacies in some aspects of ToM.

Apparently, failure in the ToM does not restrict to ASD, individuals with DS may also present difficulties in recognizing that beliefs and thoughts can be distinct from their own. These difficulties seem to be related to the cognitive relegation present in the syndrome and seem to interfere directly in the social relationships.

Yirmiya, Pilowsky, Solomonica-Levi & Shulman (1999) [16] performed a comparative study between 29 individuals with ASD, 19 with DS and 21 with cognitive impairment of unspecified origin, all aged between 10 and 21 years, grouped according to the mental age measured based on the WISC-III intelligence scale [17].

That said, the objective of this study was to verify the ability of children with DS to attribute false beliefs and to compare their results to those of typical children.

These results of [16] demonstrated that individuals with autism tend to fail more than other individuals in the recognition of the other’s thinking, however, individuals with DS also presented a slight alteration in this knowledge, when compared to the other individuals with cognitive relegation. In addition, DS individuals demonstrated to maintain focused attention for less time in the development of the experiment than the autistic individuals did, while the latter maintained eye contact for less time than the DS. Abbeduto, Pavetto, Kesin, Weisman et al. (2001) performed a comparative experiment with DS individuals and subjects with X-fragile syndrome. This syndrome, also has a genetic origin, is characterized by the presence of cognitive relegation, like DS, but it differs in relation to the behavioral profile; individuals with fragile X tend to present important behavioral issues such as psychopathology, hyperactivity, and even autistic behavior. These authors observed that individuals with DS presented more difficulty in the false-belief tasks, obtaining lower indexes in the abilities of recognition of the mental states of other people, whereas individuals with X-fragile presented correct thresholds of responses close to the children with typical development. Another research with DS was performed by [18], who applied a false-belief task quite similar to the Sally-Ann task with Brazilian children. The researchers observed that only children with mild BAOJ Pathol, an open access journal

Method All parents and / or guardians were aware of the study procedures and signed the Free and Informed Consent Form, as required by the Research Ethics Committee / Unicamp - research protocol number: CAAE 1378213.5.0000.5404, approved in Sept / 2013.

Subjects The present research had the participation of 26 children aged 6 to 13-year-old, and 5 adults, all diagnosed with DS and in therapeutic follow-up at the Support Service for School and Social Inclusion of the Association of Parents and Friends of the Exceptional (APAE) of São Paulo, Brazil. We used as criterion of selection only subjects with orality (speech production at sentence level) and cognitive relegation from mild to moderate. Assuming this criterion, the participants were chosen through the analysis of the chart and indication by the speech therapist responsible, as well as of the teachers and social workers who accompanied the subjects. The results presented by subjects with DS were compared with the results of a control group composed by 20 children with typical acquisition and development of language, aged 4 to 6-year-old.

Method For our analysis, we chose a simple false-belief task that does not involve complex non-linguistic mechanisms, both for its comprehension and to produce task responses. We adapted the Volume 1; Issue 1; 005

Citation: Arvigo MC (2017) Do Individuals with Down Syndrome Understand False-Belief Tasks?. BAOJ Pathol 1: 005.

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task developed by [19] based on the proposal of [20] in which the child takes a picture of a plush cat through a Polaroid camera.

Researcher: In the photo you took, where is Pablo sitting?

Initially, the plush cat was sitting in a certain position in the scenery set up in front of the child. Once the photo is taken and the child and the researcher observe the result, the researcher changes the place of the toy. Next, the researcher asks the child where the cat is in the picture (‘In the photograph, where is the cat?’). In response, the child is expected to state that the cat is in the initial position.

Procedure

Like Frith’s (2001) [20], the individuals with DS observed in our research were asked to take a picture of a plush toy (Pablo, a character from the children is drawing Backyardigans) who was sitting on a chair. As soon as the subject took the picture with a digital camera and watched the result, the researcher placed the toy on a table. Therefore, the researcher asked the subject to tell her where the plush toy was sitting on the photo taken. Here is an example of this dialogue between the researcher and a DS subject.

Unlike what we expected, there was a higher index of correct answers than errors to the task. Only the group of youngest SD children, aged 6 to 7-year-old, had more wrong answers than right. Among children with typical development, there were no differences between ages and there were 100% correct answers, as shown in Figure 1.

(1) Researcher: Look! Pablo is sitting in the chair. Let’s take a picture of him?

By separating children with DS by cognitive development, considering linguistic performance, rather than by age group, we have a new configuration, as shown in (Figure 2). The success rate among children with a better cognitive level is like the results of typical children.

[DS subject takes a photo with the digital camera offered by the researcher] Researcher: Let’s see the photo you took? [DS subject and researcher look at the photo taken. Then the researcher changes the position toy, while the DS subject observes]

Expected answer: In the chair. Each participant was evaluated individually in a place provided by the Institution or school. The evaluations were recorded and the results marked in a specific protocol for this research.

Results

Adults with DS had similar performance to typical children, presenting no difficulty in responding to the false belief task.

The results presented in (figure 2) suggest a possible correlation between linguistic-cognitive skills and the understanding of falsebelief.

Figure 1: Legend - DS1: Down Syndrome’s children age 6 to 7-year-old; DS2: Down Syndrome’s children age 8 to 10-year-old; DS3: Down Syndrome’s children age 11 to 13-year-old; DS T: total of children with DS; DS Ad: adults with DS; TD: typical development children.

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Citation: Arvigo MC (2017) Do Individuals with Down Syndrome Understand False-Belief Tasks?. BAOJ Pathol 1: 005.

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Figure 2: Legend - DS A: Down Syndrome’s children with better cognitive development; DS B: Down Syndrome’s children with poor cognitive development; TD: typical developmental children

Discussion Leslie & Thaiss (1992) [19] applied this task with 15 young people with ASD with an average age of 12-year-old, a minimum mental age of 4-year-old, and 20 typical children with an average age of 4-year-old and a mental age of 4.5-year-old. In addition to the photographic task, the adolescents also answered to another falsebelief task, such as the well-known Sally-Ann task. The intention here was to demonstrate a possible dissociation between the famous false-belief tasks and the false-photographic task. Their results showed that only 23% of the individuals ASD passed through the Sally-Ann false-belief task, while almost 100% of these subjects responded correctly to the task of the photograph. The authors became disappointed and concluded that falsephotographic tasks are not enough to understand the acquisition of false-belief. However, these false-belief tasks are quite controversial, since they cover different linguistic-cognitive abilities and can be solved in varied ways. Frith (2001) [20] states that the mind blindness hypothesis is often misinterpreted as indicative of the absence of explicit ToM in ASD subjects. However, this hypothesis is about a failure to recognize functions and states of mind, or mentalizing ability. Despite a flaw in this mechanism, there is an evidence that individuals with high functioning autism and, especially, individuals with Asperger’s Syndrome, may come to understand mental states through compensatory learning. However, these BAOJ Pathol, an open access journal

subjects are slower in their answers and prone to errors in more complex tests. According to the author, the failure of autistic children in tasks such as Sally-Ann is predictable because this type of task requires working memory and the ability to inhibit reality-based responses, such as pointing to the place where the object actually it is. For Frith (2001) [20], results such as Leslie & Thaiss (1992) [19] have much to say about the understanding of autistic subjects and are strong evidence that the recognition of mental functions is cognitive mechanism apart, or a modular mechanism. The results in our research resemble those obtained by [19,20], and indicate that subjects with DS, at least those observed in our research, can understand functions and mental states. This does not imply that these same subjects have a linguistic maturity to understand the possible differences in shared knowledge between speaker and listener. The establishment of common ground, or shared knowledge, plays an important role in the child’s ability to keep his or her listener’s perspective in mind. Stalnaker (1973, 1974, 1976, 1998, and 2002, among other works) [21,22,23,24,25] calls Common Ground as the presupposition of the speaker, assuming this common field as the central concept necessary to characterize the discourse. According to the author, each discourse or elocution occurs in a given context, which has a number of particular properties, such as being located at a particular time, in a specific place and / or Volume 1; Issue 1; 005

Citation: Arvigo MC (2017) Do Individuals with Down Syndrome Understand False-Belief Tasks?. BAOJ Pathol 1: 005.

in a possible world, and still involving a particular speaker and a particular listener; properties such as these make a discourse different from other possible discourses. A presupposition, Stalnaker continues (1974), is what the speaker assumes as common or mutual knowledge between himself and the other participants in the conversation, this presupposition being composed of a set of “possible worlds”, a set of possibilities compatible with all which the speaker assumes as true within context, what the author calls a “context set”. In addition, it is possible to note from the results obtained here that the knowledge of states and mental functions, consequently, the success in false-belief tasks have a relationship between the linguistic-cognitive levels. The children with DS and better linguistic performance had the same performance as the typical children, that is, they reached 100% of correct answers in the task. There is a growing interest in how typical and non-typical children develop the ability to understand mental states, and how these children use this information to explain or predict social behavior. Several researches discuss the type and degree of relationship between cognitive ability and ToM. False-belief ability emerges at about four or five year-old and can be considered as a fundamental point for the development of children’s language and social cognition itself. Recognition and an understanding of a given situation requires the child to construct a mental image by associating and relating the agent of action and the object relating to this action. The child creates this mental image through shared attention, a cognitive function. So the child must interpret the communicative behavior and the context, making links with his knowledge of the world. Silva e Silva et al. (2010) observed a relationship between the degree of cognitive relegation and the frequency of correct responses in the false-belief task. According to the authors, there was an association between the time of therapeutic intervention and the frequency of right answers, but it is important to note that only children with a degree of mild mental retardation were able to respond. These results make us consider the positive influence of the therapeutic intervention for the development of the language of children with DS, especially when the intellectual impairment is less pronounced. In summary, based on the results obtained in this research, considering the results of different researches that demonstrate that subjects with DS fail in false-belief tasks, we can assume that such subjects are able to understand states and mental functions,

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but not necessary have more complex semantic-pragmatic abilities. It is possible to suppose a close relation between the linguisticocognitive commitment and the capacity to recognize states and mental functions, as well. However, new research is needed for results that are more concrete.

Conclusion There is much to be observed regarding linguistic and semanticpragmatic abilities in DS. Our results indicate that individuals with DS may be able to understand states and mental functions, but we cannot predict their performance in more complex abilities related to ToM. The present study did not pretend to exhaust the topic of ToM in SD, but we hope open the door to important questions about this syndrome and the development of pragmatic abilities.

Acknowledgment Research grant number 18846-12-2 from the Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / CAPES supported the research reported on this paper. I am very grateful to all those who have contributed in some way to the development of this research, in special to my friend Olivier-Hugues Terreault. Many, many thanks to the children who participated in this study and their families.

References 1. Premack D, Woodruff G (1978) Does the chimpanzee have a theory of mind?. Behavioral and Brain Sciences 1(4): 515-526. 2. Baron-Cohen S (2001) Theory of mind and autism: a review. International Review of Research in Mental Retardation 23: 169-184. 3. De Villiers J (2007) The interface of language and Theory of Mind. Lingua 117(11): 1858-1878. 4. Astington JW, Gopnik A (1991) Theoretical explanations of children’s understanding of mind. British Journal of Developmental Psychology 9(1): 7-31. 5. Aichhorn M, Perner J, Kronbichler M, Staffen W, Ladurner G (2006) Do visual perspective tasks need theory of mind? NeuroImage 30(3): 1059-1068. 6. De Cat C (2013) Egocentric definiteness errors and perspective evaluation in preschool children evaluation. Journal of pragmatics 56: 5869. 7. Baron-Cohen S, Leslie AM, Frith U (1985) Does the autistic child have a theory of mind?. Cognition 21(1): 37-46. 8. Ozonoff S, Pennington B, Rogers S (1991) Executive functions in highfunctioning autistic children: relationship to Theory of Mind. Journal of Child Psychology and Psychiatry 32(7): 1081-1106. 9. Prior MR, Dahlstrom B, Squires TL (1990) Autistic children‟s knowledge of thinking and feeling states in other people. Journal of Child Psychology & Psychiatry 31(4): 587-601. Volume 1; Issue 1; 005

Citation: Arvigo MC (2017) Do Individuals with Down Syndrome Understand False-Belief Tasks?. BAOJ Pathol 1: 005.

10. Happé F, Frith U (1996) The neuropsychology of autism. Brain 119: 1377-1400. 11. Hill EL, Firth U (2003) Understanding autism: insights from mind and brain. The Royal Society Publishing 358(1403): 281-289. 12. Baron-Cohen S (1995) The autism as symbolic play. British Journal of Developmental Psychology 5: 135-148. 13. Pilowsky T, Yirmiya N, Arbelle S, Mozes T (2000) Theory of mind abilities of children with schizophrenia, children with autism, and normally developing children. Schizophrenia Research 42(2): 145-155. 14. Shaked M, Yirmiya N (2004) Matching procedures in autism research: Evidence from meta-analytic studies. Journal of Autism and Developmental Disorders 34(1): 35-40. 15. Cobos FJM, Castro MCA (2010) Theory of mind in young people with Down’s Syndrome. International Journal of Psychology and Psychological Therapy 10(3): 363-385.

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19. Leslie AM, Thaiss L (1992) Domain specificity in conceptual development: neuropsychological evidence from autism. Cognition 43(3): 225-251. 20. Frith U (2001) Mind Blindness Review and the Brain in Autism. Neuron 32(6): 969-979. 21. Stalnaker R (1973) Presuppositions. Journal of Philosophical Logic 2(4): 447-457. 22. Stalnaker RC (1974) Pragmatic Presuppositions. In: Munitzne, Under P(eds.) Semantic and Philosophy. New York University Press : 197213. 23. Stalnaker RC (1976) Possible words. Symposium to be read at the meeting of the western division of American Philosophical Association in New Orleans, Louisiana 10(1): 65-75. 24. Stalnaker R (1998) On the Representation of Context. Journal of Logic, Language, and Information 7(1): 3-19.

16. Yirmiya N, Pilowsky T, Solomonica-Levi D, Shulman C (1999) Brief report: Gaze behavior and theory of mind abilities in individuals with autism, down syndrome, and mental retardation unknown etiology. Journal of Autism and Developmental Disorders 29(4): 333-341.

25. Stalnaker RC (2002) Common Ground. Linguistics and Philosophy 25: 701-721.

17. Wechsler D (1991) Wechsler Intelligence Scale for Children. (3rd ed.) The Psychological Corporation, Harcourt Brace Jovanovich.

27. Yirmiya N, Arbelle S, Mozes T (2000) Theory of mind abilities of children with schizophrenia. Schizoph Rev 42(2): 145-155.

18. Silva TP, Silva AF, Tamanaha AC, Perissinoto J (2010) Atribuição de falsas crenças no desenvolvimento de linguagem de crianças com síndrome de Down. Revista da Sociedade Brasileira de Fonoaudiologia 15(2): 213-218.

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26. Stalnaker R (1972) Pragmatics. In: Davidson D, Harman G (eds.) Semantics of Natural Language, Dordrecht Reidel : 380-397.

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