The impairments typically observed in children with autism
Autism is a pervasive developmental disorder characterised by a range of impairments which vary enormously. Autistic spectrum disorder is a commonly used term to reflect the complex combination of symptoms that often arise before the age of three and continue through life. However there are three core features of the autistic spectrum that are fundamental in the diagnosis of autism set out by the DSM-IV (American Psychiatric Association 1994).
The first of the features implicated is a deficit in reciprocal social interaction; at first glance the child may just seem aloof and uninterested in the social world, they may find it difficult to make eye contact and struggle to form relationships with their peers, which can make the life of an autistic child very lonely. This unsociability can be misinterpreted by others as wilful behaviour when in fact they have a neurological lack of ability in this area.
The second impairment is communication, children with autism often struggle with early speech; however this only touches on the deficit with communication a child may encounter. Communication involves recognising another’s intention to communicate and offering an appropriate response. Children on the autistic spectrum may have difficulty interpreting both nuances of verbal speech and non verbal expression which in turn makes conversing with others very distressing. In addition inhibiting behaviour at inappropriate times may be troublesome for a child with autism.
The third feature, dissimilar from reciprocal interaction and communication, involves repetitive activities and narrow interests. Children with autism value sameness and do not like change, repetitive behaviour can be quite unusual such as rocking, hand flapping and putting objects in order, these behaviours are often linked to a lack of imagination. In addition to impairments children often have fantastic ability in certain areas such as music and memory (Wallace, 2008).
The triad of impairments (Wing & Gould, 1979) encompass the typical deficits in autism, however every child is unique and their symptoms and behaviours are reflected in the myriad of strengths and weaknesses that are often present. There are many cognitive theories that aim to explain these typical features; this essay will compare three theories which have dominated psychological research in autism.
First is the Theory of Mind hypothesis (TOM) which tries to account for the deficit in social interaction (Baron-Cohen, Mindblindness: An Essay on Autism and Theory of Mind. 1995), second is Executive Function theory (EF) which seeks to explain the everyday coping problems such as attention, inhibition difficulties, and repetitive behaviour (Hill, 2004) and third is the Weak Central Coherence theory (WCC) which suggests a different style of information processing that aims to account for superior abilities and deficits in contextual processing (Frith, 1989). Arguably the most typical impairment is the lack of reciprocal social interaction ability.
The Theory of Mind hypothesis (Baron-Cohen, 1995) suggests that individuals with autism fail to attribute mental states to themselves and to others (Premack & Woodruff, 1978). Support for this can be seen in an extensively used theory of mind test called the false belief task. The task examines the acceptance that other individuals can have a different understanding about the same situation. First devised by Wimmer and Perner (1983) the task involves two dolls, Sally and Anne. Sally puts a marble in the basket and then leaves; whilst Sally is away Anne removes the marble and places it in the box.
On Sally’s return the participant has to say whether Sally will think the marble is in the basket or the box. Studies have found that 80% of children with autism fail to understand that Sally will think that the marble is still in the basket (Baron-Cohen, Leslie, & Frith, 1985). It is suggested that the child with autism has no concept of another’s mental state. There have been many variations of the false belief task such as the deceptive box task (Perner, Frith, & Leslie, 1989).
A disadvantage of these results is that they are variable, studies have shown that 20% of children with autism pass the false belief tasks, this led Baron – Cohen to revise the task and create the second order belief task (Baron- Cohen, 1989) where the task is to understand ‘what he thinks, she thinks’ therefore the task is more complex. He found that children with autism were significantly impaired and suggested a delay in the development of TOM rather than a deficit. Further to this a child may use different strategies in order to pass these tests.
TOM posits a domain specific deficit so does not account for non social impairments typically seen in children with autism. In comparison the Executive Function theory of autism proposes a domain general deficit therefore aims to account for both social and non social impairments. A need for sameness, difficulty switching concentration and a lack of impulse control are all impairments seen in people with autism and Dysexecutive syndrome. DS has been linked with frontal lobe damage (Baddeley & Wilson, 1988) and this led researchers to investigate executive function deficit in autism.
The frontal lobe is associated with areas such as working memory, inhibition, attention flexibility and monitoring action (Hill, 2004). The EF theory proposes deficits in these areas are dependent on executive functioning and that children with autism are impaired in some or all of these abilities. In contrast to TOM the EF theory suggests that to pass both first and second order false belief tasks, a child must retain the information of the marble’s location which involves working memory; in addition they must inhibit a prepotent response therefore not revealing where the marble is.
In atypical children developing EF has been linked with advancement in TOM. Russell,Mauthner, Sharpe, and Tidswell (1991) found that children of 3yrs and autistic participants (compared to 4yr olds and mentally handicapped children ) failed to inhibit knowledge about a location of an object even though it would be of benefit to them ( a test of executive function). In addition the 3ry olds and the autistic children failed to deceive which is measure of TOM (Perner, Frith, & Leslie, 1989). The results are significant because it illustrates that TOM and EF are linked in the acquisition of these abilities.
This provides evidence for the developmental nature of both abilities and possibly EF is a precursor for TOM understanding. Typical children seem to move through development on both TOM and EF ability in contrast children with autism do not make it through this transition easily, if at all. Rutherford and Rogers (2003) examined the association between TOM and EF with regard to spontaneous and prompted pretend play. Pretend play involves communication, representation, imagination, planning and language skills all of which involve either TOM or EF.
Children with autism often have a marked inability to engage in pretend play either alone or with others. The TOM theory would suggest that in order to pretend that a banana is a telephone; a child would have to separate the representation of the banana from the pretend representation, the telephone. It is argued that this would require an understanding that the pretend object is not true in the real world but the child is still required to respond correctly to the representation, similar to a false belief task (Leslie, 1987).
In contrast the EF theory would propose that the separation between reality and pretend, calls for an inhibitory response where the child would suppress their knowledge of the banana. Another feature of pretend play involves generativity, which refers to the creation of new ideas (Lewis & Boucher, 1995). Generativity involves generating different actions to explore or solve problems. Rutherford and Rogers (2003) found that children with autism were considerably delayed on the pretend play scores; in addition the researchers found significant deficits in the TOM measures but not the EF measures.
Interestingly the measure of generitivity did significantly predict how well the children did on the play scale which comes under the executive function umbrella. The significance of this study is that again there seems to be a link in the developmental nature of TOM and EF. EF underlies many of the impairment characterized in children with autism; however the difficulty with EF theory is that problems with executive function can be displayed in other disorders such as Attention Deficit Hyperactivity Disorder (ADHD) and Writing/Reading Disorder (Nyden, Gillberg, Hjelmquist, & Heiman, 1999)
Poor joint attention, poor understanding of non literal language such as sarcasm and joke telling (Tager- Flusberg 1993) and persistent difficulty in social interactions are all impairments that can be explained by the TOM deficit but TOM does not account for other social impairments such as lack of emotional control or lack of attention to voices or faces. In comparison EF theory can explain the inability to plan ahead, monitor behaviour and respond flexibly to changes. TOM and EF theories fail to explain the sometimes special talents often exhibited in children with autism.
Frith, (1989) put forward the idea that deficits and talents possibly originate from the same place; she coined the term central coherence to describe the way in which humans process information in its context. The Weak Central Coherence theory (CCT) proposes that instead of processing information as a whole and in context, children with autism may process information in a detailed fashion. CCT proposes an information processing style and aims to explain certain behaviours such as a high attention to detail, the need for sameness, sensitivity to stimuli, and fantastic abilities such as mathematics, music and memory.
Frith, (1989) suggested that children with autism process information in a piece by piece way rather than seeing and understanding the stimuli in context. Evidence for this can be seen in many empirical studies conducted over the last twenty years. Shah and Frith, 1993 found that children with autism had an enhanced performance on a block design test where children had to recreate a nonsense shape, the authors concluded that the participants were exhibiting local processing ability at the expense of seeing the object as a whole.
Children with autism have also shown a local processing approach in the Embedded figures section of the Wechsler intelligence test where the child has to find a shape embedded in a much more complicated pattern (Joliffe & Baron – Cohen, 1997). These studies suggest that the child is more dependent on perception therefore has to take up a more local approach. This attention to detail of stimuli in the environment could possibly explain restricted behaviour as the child can only focus on specific details at a time at the expense of global understanding.
These perceptions can be described as positive or negative, for example a positive symptom could be the ability to understand music (Mottron, Peretz, & Menard, 2000) and a negative sympton could be lack of eye contact in social interaction (Pelphrey, Sasson, Reznick, Goldman, & Piven, 2002). It is proposed that the positive symptoms could explain heightened ability and negative symptoms could explain the unusual local processing style. In a study conducted by Teunisse, Cools, Van Spaendonck, Aerts and Berger (2001), the authors tested the prevelence of WCC and EF.
The authors tested EF with a battery of card sorting tests whereby the participants had to discover and shift attention to several sorting priciples. An example of this would be the Wisconsin card sorting test (Berg, 1948), which measures the ability to shift attention by asking the participant to sort the cards into colour, form, and number. The amount of trials were counted and the highest number of trials needed to sort the cards depicted poor attention shifting.
CC, measured by the Embedded figure test. Teunisse, et, al. 2001), found that CC and poor attention shifting were found not to be related to the severity of the symptoms in autistic spectrum disorder however weak CC and poor attention shifting were found to be significantly more widespread in the autistic group than found in the general population. The relavence of this is that although WCC and executive dysfunction were both present in the autistic group these cognitive styles were not universal to autism. It is argued that EF is necessary for information processing in a global context therefore executive dysfunction possibly underpins the WCC account.
Detail processing has been found across the autistic spectrum (Happe,1997) however this type of processing has been found to occur regardless of the childs ability to use TOM. This would suggest that TOM and WCC are two distinct explanations for the deficits in social intraction and possible superiorty in detailed focussing. The relationship between TOM and WCC was investigated by Happe (1994). She found that TOM was not related to the performance on the Block design subtest of the Wechsler scales which is a measure of CC but TOM was related to the Comprehension subtest which requires pragmatics and social skill.
WCC theory could possibly explain how a child processes language and TOM may explain how a child comprehends language. Usually to understand jokes a person needs to put it in context (TOM), a child on the autistic spectrum may not grasp the global meaning (WCC) and focus on the joke in a literal way. This would no doubt cause difficulty and confusion in the lives of children with ASD. TOM and EF theory do not encompass the whole spectum impairments of ASD, particularly the theory posited by WCC that the autistic child’s enhanced abilities is at the expense of global understanding.
TOM seeks to explain the mentalizing deficits found in ASD but does not explain the all social impairments such as emotional control or lack of attention to faces. Furthermore there is quite a lot of variation in the results of TOM tests. Possibly the tests need to be revised to tap into the true nature of social interaction. EF theory explains the lack of inhibition as displayed in the deception task and the lack of imagination as displayed in the pretend play study but as impairments such as infexibility can be seen in children with ADHD and reading/writing disorders this theory lacks definition.
Nevertheless each theory as well as standing alone enhances or expands on the others. There seems to be an association between TOM and EF in that certain executive functions need to be in place for full understanding of another’s mental state. Just as there are multiple impairments found in Autistic Spectrum Disorders so there will be the need for numbers of theories exploring and attempting to explain its complexities. Researchers may never find a single causal factor to explain autism but cognitive theories will develop and expand and hopefully help the lives that are affected by this puzzling disorder.