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Executive Dysfunction Theory Essay

Since the awareness of autism researchers have investigated two paradigms to explain autism; the cognitive and the psychodynamic. For the purpose of this essay I will be analysing the cognitive paradigm. The cognitive theories explains the unique elements of behaviour (Happi, Ronald & Plomin, 2006). The preponderate theories being the theory of mind, central coherence theory and executive dysfunction. These theories complement each other rather than compete and I will explore how they affect learning.

Theory of mind (ToM): In this model, autism is defined as a neurodevelopment dysfunction that causes empathy disorder which can also be called mind blindness (Baron-Cohen, 2011). People with this condition will find it difficult to put themselves into someone else’s shoes or think of other people’s feeling. (Frith & Harpe 1994). This model was tested using the Sally-Anne experiment which favoured the theory but other tests shows that there is a discrepancy the results. (Frederickson et al, 2000).

The theory was not specific as it can be found in other people e. . congenital blindness and deafness and conditions such as dementia. The universality was argued both ways as Baron-Cohen thinks all people with ASC lack ToM while some writers believe they are not (Happe, 1994). Although the Sally Anne test only looks at one aspect of ToM, it was said to be potentially testable. in scope it can account for difficulties in social interaction and communication. The link to repetitive behaviours and rigidity, however it’s more difficult to see. Whilst there was a lot of evidence to support ToM, it was superseded by newer theories.

Central coherence theory: this theory describes the concentration and how the individual understands information on face value rather than the message as a whole (Shah & Frith, 1993). This also looks at the anxiety and stress level of a person with ASC as they might not be able to cope with unpredicted scenarios(Happe & Frith , 2006) this theory was tested and the results were inconsistent (Volkmar et al, 2004) . Executive dysfunction: This has been explained as a blanket term as it encompasses the flexibility, working memory, impulse control and the monitoring of actions (Struss & Knight, 2013) which could cause learning challenges.

Researchers found that the results of executive function varied. Ozonoff, Pennington and Rogers (1991) found 90% of their participants with autism did worse than their controlled group whilst Pellican et al. (2006) found only 50 % showed executive difficulties. Due to the complex concept of the Executive function (EF), understanding how it may affect our practical lives might be difficult to explain especially when it is impaired which is expected to be the case with someone with ASC.

It was concluded the executive dysfunction is not unique to ASC, however it is part of the theories that explains the cognitive functioning in autism (Hill, 2004). These components of four cognitive parts; planning, mental flexibility, inhibition and generativity (Barnard L, et al , 2008, Gilotty L,et al 2002, Firestone P & Dozois JA , 2007 , Hill , 2004). a. Planning: this is the ability to organise ahead by being impartial with one approach to choices and the ability to implement and revise accordingly.

A typical task used to assess planning is the Tower of London, this requires the participants to move disks from a prearranged sequence to match the examiners goal. This task was done with very few moves and there was set rules. The participants were children with ASC whose IQ score were high and the other set were children who were neuro-typical with low IQ or intellectually impaired (Ozonoff et al, 1991). After the task it was reported that the children with ASC were significantly impaired on the task compared to the other group (Hughes et al. 1991).

However when the same task was performed in a computerised version, the report showed normal performance for children with ASC whose IQ were above 70 %. The report also showed that the neuro-typical older children (11-16 years old) children did better than the neuro-typical younger children (I8-10 years old) which suggested that planning ability might be more related to the level of IQ and maturity rather than autism (Mari, Castiello, Marks, Marraffa, and Prior (2003). Due to the way the task was carried out, the performance report was therefore imprecise (Happe et al. , 2006).

b. Mental flexibility: This is the ability to transition to another activity or task readily in response to situational changes. To assess this The Wisconsin Card Sorting Task (WCST) (Heaton, Chelune, Talley, Kay, & Curtis, 1993) was used. This requires participants to sort cards following a non-spoken rule, which could be colour, shape or number. The inability to shift to a new sorting strategy is mostly seen as the primary index of executive dysfunction (Hill, 2004). The report shows people with autism as children with autism have been reported to be very single minded on this task compared to neuro-typical children and children with other evelopmental disorders (Geurts et al. , 2004; Liss et al. , 2001; Ozonoff & Jensen, 1999; Ozonoff et al. , 1991; Rumsey, 1985).

Report found that children with ASC found it difficult to shift to another rule and stuck to their first way of sorting which was what happened to the other groups as well (Ozonoff & Jensen, 1999; Prior & Hoffmann, 1990). However, Nyden, Gillberg, Hjelmquist, & Heiman, 1999). Ozonoff and McEvoy (1994) followed up the participants and found individuals with ASC to be more single minded when compared to neuro-typical children and children with other developmental disorders (ref).

Furthermore the result was inconclusive because there was no constant measure for scoring and when compared to the computerised version, individuals with ASC were less single minded which was weighed as reduced demands in social and verbal tasks (ref), Ozonoff (1995) and suggested that this may be related to verbal ability, the task demands and general intellectual functioning. c. Inhibition: This is the ability to suppress inappropriate information or impulse. The Stroop task (Stroop, 1935) requires participants to name the colour that words are written in but ignore the word representing colour itself which could be yellow or green.

Report shows that there was not much difference between putting level of intellectual functioning, interference effects for children and adults with ASD when traditional card versions was used for this task (Hill & Bird, 2006; Ozonoff & Jensen, 1999; Russell et al. , 1999). However children with ADHD and Tourette syndrome showed more signs of impairment (Ozonoff & Jensen, 1999). After a long debate, inhibition was no longer general considered an executive function deficit in people with autism. (Barnard L et al, 2008, Hill, 2004).

The result from tests carried out did not indicate a general pattern in individuals with autism. (Hill, 2004). The way inhibition was measured could be questioned and the focus was on impaired performance instead of a core deficit. (Hill, 2004) as generally individual with autism do better on tasks without metallization (ward, 2006). The stroop (ref) was not investigated using a computerised version, however when the task was performed using two boxes, one with visible desired objects and the other empty.

The children were asked to point to the empty box and consistently, children with ASC had poor performance which was an indication of inhibition difficulty (Biro & Russell, 2001; Hughes & Russell, 1993; Russell, Hala, & Hill, 2003; Russell, Mauthner, Sharpe, & Tidswell, 1991). d. Generativity: this is the ability to spontaneously generate novel ideas and behaviours and it is thought to be a cause of the lack of spontaneity and initiative in autism, poverty of speech and action, and apparent failure to engage in pretence.

Turner (1997) reported a correlational link between a poor performance in fluency tasks and high levels of repetitive behaviour in daily life, suggesting that generativity deficits could hinder the ability of controlling, regulating, and modifying behaviours. Self-monitoring refers to the process that enables individuals to see themselves as the makers of the changes when facing perceptual inputs, actions, and mental episodes.

Studies have provided mixed evidence on a specific deficit in self-monitoring in ASD when compared with matched control groups, children with moderate learning disability and normally developing children. Monitoring one’s verbal output is required on tests of verbal fluency to prevent items repetition; only one study investigated the frequency of words repetition in fluency tasks, reporting more perseverative responses in ASD than in control children. Currently, there is debate among scholars regarding how to operationalize and measure executive functions.

These functions generally are referred to as “supervisory” cognitive processes because they involve higher level organization and execution of complex thoughts and behaviour (ref). Although conceptualizations vary regarding what mental processes actually constitute the “executive function” construct, there has been a historical linkage of these “higher-level” processes with the frontal lobes (ref). In fact, many investigators have used the term “frontal functions” synonymously with “executive functions” despite evidence that contradicts this synonymous usage.

The current review provides a critical analysis of lesion and neuroimaging studies using three popular executive function measures (Wisconsin Card Sorting Test, Phonemic Verbal Fluency, and Stroop Color Word Interference Test) in order to examine the validity of the executive function construct in terms of its relation to activation and damage to the frontal lobes. Empirical lesion data are examined via meta-analysis procedures along with formula derivatives. Results reveal mixed evidence that does not support a one-to-one relationship between executive functions and frontal lobe activity.

The paper concludes with a discussion of the implications of construing the validity of these neuropsychological tests in anatomical, rather than cognitive and behavioural terms. Successful attempts in fractionating the executive system will depend to a considerable extent on the ability to develop more specific models of executive functions (Fan, McCandliss, Sommer, Raz, & Posner, 2002; Posner & Raichle, 1994; Shallice, 1988; Shallice & Burgess, 1991). The understanding of how it affects children with ASC would be useful on impacting their education.

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