Executive Function Theory Essay

Abstract
Autism is a neurodevelopmental disorder that has been a significant topic of research over the last few decades. While there is no conclusive findings as to what causes Autism, there are many reasonable theories that help to explain how this particular disorder develops. The purpose of this review is to explore and discuss various theories presented in biopsychology as to what causes Autism. Through the examination of several articles and studies, several theories will be presented. Such theories will include the Executive Function Theory, the effect of thimersol and vaccines, the effect of SHANK3, environmental factors, and genetics, all of which will be discussed in further detail.
Key words: Autism, biopsychology, neurodevelopment

disorders, Executive Function Theory, SHANK3, thimersol, vaccines, environmental, genetics,

Biopsychology and Autism: A Literature Review
There are many different disorders that can result from even the slightest differences in neurodevelopment. These differences can interrupt consequent stages and have extensive and lasting symptoms that can affect an individual over the course of their life (Pinel, 2014). One such disorder that is gaining more momentum in research and awareness in society is autism (AU). Autism is a very “complex neurodevelopmental disorder” that has an extremely broad range of symptoms (Pinel, 2014, p. 227). These symptoms often mimic the characteristics of other disorders, which can obscure and even delay diagnosis. In fact, many of these disorders fit under an umbrella of Autism Spectrum Disorder (ASD) which can also further complicate diagnosis. A spectrum disorder is generally used when there are a group of associated disorders present (Pinel, 2014). There has not yet been a definitive cause that has been discovered for autism, however, there are many theories in biopsychology that seek to identify what may elicit this particular disorder, all of which will be discussed in further detail.
Definition, Diagnosis, and Characteristics
Autism is a heterogeneous disorder that is believed to be present in 1 out 110 children in the United States (Ratajczak, 2008). It is typically described in “terms of social communication impairment and restricted repetitive behaviors” (Williams, Woolfenden, Roberts, Rodgers, Bartak, & Prior, 2014, p. 336). Currently, autism is commonly diagnosed by using guidelines from the fifth edition of The Diagnostic and Statistical Manual of Mental Disorders (DSM-5) (Williams et al, 2014). Measures used in diagnosis include meeting “three social communication criteria and four restricted and repetitive types of behavior” (Williams et al, 2014). Once diagnosis is confirmed, different types of interventions and strategies can be better utilized.
While every person is unique, there are many who believe that individuals with autism may show distinct physical characteristics. These unique characteristics may include “dysplastic nails, large or prominent ears, long eyelashes, wide nasal bridge, bulbous nose and sacral dimple” (Bentacur & Buxbaum, 2013). Additionally, there are many behavioral characteristics that individuals with autism may also share. These particular traits may include (but are certainly not limited to) “) a reduced ability to interpret the emotions and intentions of others, a reduced capacity for social interaction and communication, and a preoccupation with a single subject or activity” (Pinel, 2014, p. 227). Additional characteristics may include and range from above average to superior performance in various areas (such as reading, math, or music), impaired language development, and/or self-injurious tendencies, to name a few. It is important to note that while these symptoms are common, they are not always present in every individual (Pinel, 2014).
Specific Theories of Autism
As mentioned, there has yet to be a specific cause for autism to be identified. However, there are many theories that seek to explain the etiology of autism and the behaviors that are often associated with this disorder. Many of these theories are of the same principle context that damage to the amygdala may have a significant impact in the cause of autism and its associated behaviors (Maino, Viola, & Donati, 2009). Such theories include the Theory of Mind and Executive Function Theory, which focus primarily on what impact neurophysiological pathways and neurodevelopmental discrepancies of the brain may have on autism.
Theory of Mind and the Executive Function Theory.

Part of the disruption in communication and social interaction that occurs with many individuals who have autism can be better explained by the Theory of Mind and Executive Function Theory. These two theories are very similar in nature in that they both place great emphasis on the executive function of the mind. Executive functions are “cognitive abilities that appear to depend on the prefrontal cortex” of the brain (Pinel, 2014, p. 349). Executive function also encompasses “innovative thinking, lateral thinking, insightful thinking, and assimilating new information to update plans and strategies” (Pinel, 2014, p. 349). This is significant because the executive function of the brain can impact one’s ability to empathize and relate to others, interpret and sustain social interactions, and process new information (Williams et al, 2014). Many times individuals with autism are unable to understand and process what others are feeling. For example, they can recognize sadness or when somebody is crying, but they do not associate with it. It’s not that they don’t feel these emotions themselves, they absolutely do. However, they may have trouble connecting and relating to those feelings when they see somebody else experiencing them. This can result in difficulty in making and sustaining relationships with

others.
The executive function theory hypothesizes that specific behaviors associated with autism are a form of “frontal lobe preservation” that is associated with the inability to “shift attention” (Baron-Cohen, 2004, p. 74). Such behaviors include the “need for routines and sameness” as well as repetitive behavior (Baron-Cohen, 2004, p. 74). Disruption in this area of the brain can lead to decreased impulse control as well as the inability to organize thoughts (Baron-Cohen, 2004). Individuals with autism may experience an overwhelming need for routines and may strongly resist disruption in these routines. Change in general can cause an outward expression of anger, frustration, and confusion and is amplified by the inability to process the new information that change is accompanied with. Because they may also experience poor impulse control, these outwards expressions may include yelling, crying, screaming, and even physical aggression towards others or themselves.
The theory of mind (also known as “mind-blindness”) compliments and helps to support the executive function theory and states that damage in neurological pathways can lead to “deficits in the normal process of thinking” (Baron-Cohen, 2014, p. 74). Additionally, this theory hypothesizes that because of disturbances in neurological pathways one’s ability to empathize with others as well as their executive functioning may be significantly compromised (Williams et al, 2014). Social brain pioneer Leslie Brothers conducted research that helped to further substantiate the latter two theories. Brothers believed that there is a neural basis for of social intelligence or empathy (Baron-Cohen, 2004). In her research, she discovered that lesions of primate amygdala affected the social behavior of primates. These primates displayed behaviors of social isolation, did not respond fittingly to social signals, and failed to initiate any type of social interactions (Baron-Cohen, 2004). The findings from this research further prove that disruptions in specific areas of the brain (such as the amygdala) can significantly affect an individual’s capacity for social interactions and empathy. Over all, both the executive function theory and the theory of mind are meaningful because they help to offer further insight in the social inabilities that individual’s with autism often suffer from.
Prenatal Development. Another theory gaining support is that of disorganized brain cells during prenatal development. During the second-third trimester of pregnancy, the cortex of the brain will develop into six different layers (Laidmen, 2014). However, it is believed that when something goes wrong during this process it can result in damage the areas of the brain that are responsible for language development and social relations (Laidmen, 2014). This is very significant because many (although not all) individuals with autism may be non-verbal or their primary interest and motivation in communication is to only express their wants and/or needs.
Eric Courchesne (the director of the Autism Center of Excellence) conducted a study in which he examined the brains of 22 children who died between the ages of 2 and 15 years of age (Laidmen, 2014). Half of the brains were from children with autism and the other half were from children who did not have the disorder and during the examination of the brains, Courchesne and his associates discovered the occurrence of the developmental error (Laidmen, 2014). Additionally, they uncovered that 10 out of the 11 brains associated with autism had “disorganized patches in which gene expression indicated cells were not where they were supposed to be” and all where fold of the prefrontal cortex (Laidmen, 2014). Interestingly, the prefrontal cortex is associated with higher-order communication and also has connections to the amygdala, the area that is believed to be associated with social interactions.
Genetics, Vaccines, and Environment
There are many theories that suggest genetics, vaccines, and the environment play a pivotal role in the cause of autism. While nothing has been proven conclusively, there is evidence to support each theory and further indicates that there is a combination of elements that may be responsible for the development of this disorder. Examples for each will be discussed in greater detail.
Genetics. Research has proven that “genetic factors influence the development of autism” and that siblings of a child with autism have a 5% chance of also being diagnosed with AU. (Pinel, 2014, p. 228). Interestingly, if one monozygotic twin is born with autism, then there is a 60% chance that the other twin will be diagnosed with the disorder (Pinel, 2014). Currently, there has not been a single particular gene that has been isolated to be the sole cause of this disorder, however, it is believed that “several genes interacting with the environment” may trigger autism (Pinel, 2014, p. 228). In fact, modern research indicates that there are over 1,000 different genes that may contribute to causing individuals to be genetically at risk for AU (Bentacur & Buxbaum, 2013).Yet still, there is growing belief that a gene called SHANK3 may have a significant impact in the development of autism. SHANK3 codes a scaffolding protein that is critical for communication between neurons (Bentacur & Buxbaum, 2013). One study in particular sought to identify a correlation between a mutation of SHANK3 and ASD disorders. This sample of this study was 32 individuals with SHANK3 haploinsufficiency who were all evaluated for autism using the standard diagnostic criteria (Bentacur & Buxbaum, 2013). The findings of the study indicated that “84% (27/32) met criteria for ASD, including 75% (24/32) meeting criteria for autism” (Bentacur & Buxbaum, 2013). These findings implicate that when there is a mutation or damage present in the SHANK3 gene, the result can lead to autism.
Vaccines. Over the last few years, there has been a lot of heated debate over the relation to vaccines and autism. Many believe that the two are directly connected in that vaccines cause autism while others believe the correlation is coincidental given the incidence of vaccines administered to children versus the incidence of autism in children. This topic has been especially fueled by parents who have noted normal development in their child until they are administered certain vaccinations around 18 months of age (Ratajczak, 2008). In order to better understand the controversy, it is important to examine its basis in further detail.
Our immune systems are comprised of both the innate immune system and the adaptive immune system which contain lymphocytes known as B-cells and T-cells (Pinel, 2014). These systems are functioning in newborns, however, “the polymorphonuclear cells are less in number than the lymphocytes in the peripheral blood” at around 2 months old, which makes the immune system particularly sensitive this age (Ratajczak, 2008). Additionally, the phagocytic cells are at a reduced functioning level at this time and by typical medical standards, infants should receive at least six vaccinations to prevent disease by 2 months of age (Ratajczak, 2008). Since vaccines involve administering small doses of a live (sometimes inactive) virus, many believe that giving vaccinations while an infant’s immune system is still developing can be harmful and result in the onset of AU (Ratajczak, 2008).
Another concern in vaccinations in relation to autism stemmed from use of the disinfectant thimersol previously used in many vaccinations. Thimersol contains mercury and mercury exposure has been a correlated element in many symptoms that are also present in autism (Hyman, 2008). These symptoms include “psychiatric disturbances (e.g., impairments in sociality, stereotypic behaviors, depression, anxiety disorder, and neuroses)” and increased physical ailments such as asthma and allergies, and amplified incidences of “IgG autoantibodies against brain and myelin basic proteins, reductions in natural killer cell function” (Ratajczak, 2008). Additionally, brains from autistic individuals have shown neurotransmitter irregularities that are consistent with mercury exposure (Ratajczak, 2008). This is very significant because individuals with AU often have decreased levels of glutathione, a compound in the body that promotes detoxification (Hyman, 2008). Because these individuals have great difficulty in breaking down heavy metals such as mercury, the element will stay and gradually build up in the body resulting in overexposure and causing irreparable damage. Although thimersol has been proven to be harmful and has since been removed from vaccinations it still remains present in most influenza vaccines, which is still strongly recommended for children and pregnant women (Ratajczak, 2008). Despite the mounting evidence against mercury in vaccinations and it’s relation to autism, research has proven that the incidence of autism has not decreased since the removal of thimersol in vaccinations (Deisher & Doan, 2015). While it is said that research has largely proven that vaccines do not cause autism, studies have also indicated that vaccines can trigger an onset of the disorder in genetically at-risk children for ASD.
Environment.