Component 3 questions: ASD
‘Outline the characteristics of autistic spectrum behaviours.’ (10)(2018)
The characteristics of autism spectrum disorder (ASD) fall into impairments of two categories: social
communication/interaction and repetitive behaviour/restricted interests. For a diagnosis of ASD, the
individual must have impairments in both.
Social communication/interaction (SC/I) contains three elements: social-emotional reciprocity, non-
verbal communication, and developing and maintaining relationships. Those with ASD may struggle to
convey their interests and emotions; this can often result in an extreme reaction due to feeling
unheard. They can also find it difficult to initiate conversations, or alternatively, they can make
conversions one-sided about their own niche interests (e.g. dinosaurs, horses, monopoly, etc), or
respond to others inappropriately (licking, touching, etc). Non-verbal communication is when people
with ASD can rarely uses facial expressions or use them when they do not match the content of the
conversation. They can also have trouble interpreting the emotions of others by their non-verbal
communication (e.g. hand gestures, facial expressions). They can also sometimes sit too close or turn
their backs during a conversation with another person. Finally, they can struggle to see the world from
someone else’s perspective, being unaware of social norms, and finding it difficult to make
friends/build relationships with others compared to people without ASD.
Repetitive behaviour/restricted interests (RB/RI) contains 4 elements: repetitive behaviour patterns,
routines/rituals, and resistance to change, restricted/fixed interests, and usual reactions to sensory
input. Repetitive behaviour patterns includes doing one action again and again, for example, those
with ASD often displays echolalia, where they repeat what they hears from others (e.g. repeating a
quote from the TV). They can use extremely formal language (Little Professor Syndrome) or repetitive
hand gestures, like flapping. They often hold routines (e.g. lines dolls up in the same way every time),
with no variation, and overreactions to change in this routine. They often struggle to recognise
sarcasm and irony as they break the rules of ‘normal speech,’ for example, “its raining cats and dogs.”
Their restricted interests can create an intense preoccupation with a niche thing (e.g. dolls, cars), and
they often ignore others when they are occupied with them. Those with ASD are often either sensory
avoidant or sensory seeker. For example, sensory avoidant can be a resistance to touch (e.g. refusing
to brush their hair). Sensory seeker, for instance, can be where the individual can feel like they cannot
get enough of one stimulus (e.g. spinning around fast for extended periods of time).
For a diagnosis of ASD, symptoms are compared to a set criteria of the ASD manual, ICD-10 in the
UK and Europe, DSM-5 in the USA. The specialists evaluate their characteristics against the two
categories of SC/I and RB/RI, by ensuring that they have impairments in both categories for a
diagnosis. The diagnosis of ASD has 3 levels of severity in the DSM-5: high, medium, and low need
ASD. The ICD-10 still holds several types of ASD, childhood, atypical, low need, retts). If the individual
displays symptoms of ASD from both categories, they can be diagnosed with ASD.
Females being assessed for ASD can often face a hard, lengthy process of being diagnosed due to
their gender. This is due to the current diagnostic criteria for autism being developed using boys with
ASD. Girls’ neurodivergent brains are different to those of boys, so they are not always going to match
the criteria exactly. For instance, a girl’s restricted interest and obsession with dolls can be seen as
more of a ‘normal’ interest, as dolls are a common toy for female children; this could have slowed
down the diagnostic process due to this not being an abnormal issue. Girls are also more likely to be
misdiagnosed with obsessive compulsive disorder (OCD) prior to an ASD diagnosis, OCD, ADHD,
and anorexia instead of ASD, due to their cases being seen as less severe than boys’ as they do not
match the criteria precisely.
,“Deborah has recently been diagnosed with autistic spectrum behaviours.
Deborah's parents have noticed that her behaviour and linguistic patterns are different to other
children of her age.”
‘Describe how the characteristics of Deborah's behaviour would be different to other children.’
(15)(2021)
The characteristics of autism spectrum disorder (ASD) fall into impairments of two categories: social
communication/interaction and repetitive behaviour/restricted interests. Deborah’s diagnosis of ASD
was against a set criteria of these two categories, in the UK, it is called ICD-10.
Social communication/interaction (SC/I) contains three elements: social-emotional reciprocity, non-
verbal communication, and developing and maintaining relationships. Deborah struggles to convey
her interests and emotions; she can scream and cry when she feels unheard. She also finds it difficult
to initiate a conversation at school, or alternatively, she can make conversions one-sided about her
niche interests in dolls, or respond inappropriately (licking, touching, etc). Deborah’s parents have
noticed how her non-verbal communication is when Deborah rarely uses facial expressions or uses
them when they do not match the content of the conversation. Deborah also sometimes sits too close
or turns her back during a conversation with her teachers and parents. Finally, Deborah struggles to
see the world from someone else’s perspective, being unaware of social norms, and finding it difficult
to make friends at school compared to people without ASD.
Repetitive behaviour/restricted interests (RB/RI) contains 4 elements: repetitive behaviour patterns,
routines/rituals, and resistance to change, restricted/fixed interests, and usual reactions to sensory
input. Deborah often displays echolalia, when she repeats what she hears from the TV, or she can
use extremely formal language or repetitive hand gestures, like flapping. She lines her dolls up in the
same way every time, no variation to the way she plays with them, overreacting to change in this
routine. She struggles to recognise sarcasm and irony as they break the rules of ‘normal speech,’ for
example, “its raining cats and dogs.” Deborah has an intense preoccupation with a niche interest,
dolls, and she often ignores others when she is playing with them. Deborah is sensory avoidant to
touch; she often refuses to brush her hair as a result of this, sometimes having a panic attack.
However, she is a sensory seeker to movement, she can spend hours spinning really fast.
Deborah was diagnosed with ASD when her symptoms were compared to a set criteria of the ASD
manual, ICD-10, where she was diagnosed. The specialists evaluated her characteristics against the
two categories of SC/I and RB/RI, by ensuring that she had impairments in both categories for her
diagnosis. The diagnosis of ASD has 3 levels of severity in the ICD-10: high, medium, and low need
ASD. Deborah displays multiple symptoms of ASD, so she was diagnosed with high-need ASD. Her
“behaviour and linguistic patterns” are a main issue for Deborah, making SC/I the dominant
characteristics of her diagnosis, for example, non-verbal communication and social-emotional
reciprocity.
Deborah had a hard, lengthy process of being diagnosed due to her gender. This is due to the current
diagnostic criteria for autism being developed using boys with ASD. Girls’ neurodivergent brains are
different to those of boys, so they are not always going to match the criteria exactly. For instance,
Deborah’s obsession with dolls can be seen as more of a ‘normal’ interest, as dolls are a common toy
for female children; this could have slowed down her diagnostic process due to this not being an
abnormal issue. Deborah was misdiagnosed with obsessive compulsive disorder (OCD) prior to her
ASD diagnosis, due to her symptoms like routines/rituals and resistance to change. Girls are often
misdiagnosed with disorders like OCD, ADHD, and anorexia instead of ASD, due to their cases being
seen as less severe than boys’ as they do not match the criteria precisely.
‘Describe one biological explanation of autistic spectrum behaviours.’ (10)(2019)
One biological explanation for autism spectrum disorder (ASD) considers the role of the genetic
make-up of the individual in influencing their risk of developing an autistic spectrum disorder. This
explanation states that those with ASD have a genetic predisposition to the disorder and only 1% to
the general population. This would suggest that there is a genetic trend in the onset of ASD.
Family history studies are an efficient way of investigating genetic trends in ASD because they
evaluate the concordance rates between family members for ASD. For instance, evidence has shown
,a slight but significant trend for ASD to appear in siblings. Szatmari (1999) combined data from
several family studies to calculate the ‘sibling risk’. The risk was found to be 2.2%, which is significant
from the risk for someone with no siblings with ASD is 0.11%. This highlights that having a sibling with
ASD makes people 20x more likely to develop it themselves, demonstrating a genetic trend in ASD.
Therefore, family studies are valuable into investigating genetic trends in ASD as this study shows
that the likelihood of developing ASD is higher for people with a family history of it.
Similarly, twin studies are an effective way to investigate genetic trends in ASD as they analyse the
genes of identical (MZ) twins and non-identical (DZ) twins. For example, Ritvo et al (1985), found a
concordance rate of ASD of 96% in MZ twins and 23% in DZ twins. This shows genetic trends in ASD
as MZ twins share 100% of DNA, and DZ twins share 50%, and this is reflected in the concordance
rates, as for MZ twins, it is significantly higher. These rates are significant and is a good argument that
ASD is caused by genetics. It demonstrates that the closer individuals are genetically, the more likely
that they both will have ASD. However, due to the results not precisely matching their genetic
symmetry, we can not confidently conclude that ASD is purely caused by genetics, we must consider
other factors (for example, amygdala dysfunction, individual differences, etc).
Another way to examine the genetic trends in ASD is looking at simplex versus multiplex families.
Simplex families are when only one member is diagnosed with ASD/shows symptoms of ASD; this is
due to a new genetic mutation occurs during fertilisation. This mutation affects multiple genes, which
are called copy number variations (CNVs). CNVs account for 10% of all diagnosed cases of ASD, and
it more likely to happen if the parents are older (e.g. mother is 35+ at fertilisation). This highlights that
ASD can be caused by something going wrongly during fertilisation. On the other hand, multiplex
families are when multiple members have a diagnosis of ASD/show autistic traits. Multiplex families
show that ASD is likely to be caused by inherited genetic variations, suggesting that genes play a key
role in ASD. Therefore, these arguments both support the theory that genetics play a part in
developing ASD.
Finally, we can use non-syndromes versus syndromic diagnoses to evaluate the genetic role in ASD.
Non-syndromic diagnoses include ASD being diagnosed on its own; this shows that it is unclear what
the underlying genetic cause is as we can not find the specific gene, if there is one, causing the onset
of ASD. Whereas syndromic diagnoses of ASD include it being accompanied by another condition. If
the other condition has a well-established genetic cause, known as a single gene, it can help us to
understand the genetic causes of ASD further. For example, Fragile X Syndrome (FXS) is caused by
a mutation in the FMR1 gene; 60% of these cases also meet the diagnostic criteria for ASD. This
could help us to understand the genes involved with ASD, as the FMR1 gene could potentially be
involved.
‘Describe biological explanations of autistic spectrum disorders.’ (10)(2024)
One biological explanation for autism spectrum disorder (ASD) considers the role of the genetic
make-up of the individual in influencing their risk of developing an autistic spectrum disorder. This
explanation states that those with ASD have a genetic predisposition to the disorder and only 1% for
the general population. This would suggest that there is a genetic trend in the onset of ASD.
Twin studies are an effective way to investigate genetic trends in ASD as they analyse the genes of
identical (MZ) twins and non-identical (DZ) twins. For example, Ritvo et al (1985), found a
concordance rate of ASD of 96% in MZ twins and 23% in DZ twins. This shows genetic trends in ASD
as MZ twins share 100% of DNA, and DZ twins share 50%, and this is reflected in the concordance
rates, as for MZ twins, it is significantly higher. These rates are significant and is a good argument that
ASD is caused by genetics. It demonstrates that the closer individuals are genetically, the more likely
that they both will have ASD. However, due to the results not precisely matching their genetic
symmetry, we can not confidently conclude that ASD is purely caused by genetics, we must consider
other factors (for example, amygdala dysfunction, individual differences, etc).
We can also use non-syndromes versus syndromic diagnoses to evaluate the genetic role in ASD.
Non-syndromic diagnoses include ASD being diagnosed on its own; this shows that it is unclear what
the underlying genetic cause is as we can not find the specific gene, if there is one, causing the onset
of ASD. Whereas syndromic diagnoses of ASD include it being accompanied by another condition. If
the other condition has a well-established genetic cause, known as a single gene, it can help us to
, understand the genetic causes of ASD further. For example, Fragile X Syndrome (FXS) is caused by
a mutation in the FMR1 gene; 60% of these cases also meet the diagnostic criteria for ASD. This
could help us to understand the genes involved with ASD, as the FMR1 gene could potentially be
involved.
Amygdala dysfunction is another biological explanation of ASD as researchers have looked to the
brain for abnormalities in structure and function that may characterise those diagnosed with ASD. The
amygdala in particular is seen as significant due to its central role in regulating the behaviours that are
impacted in ASD.
Amygdala development in ASD was found to be faster in children with ASD compared to neurotypical
children. Nordahl et al (2012) found that from 2 years old, there is a larger growth in the amygdala
volume in children with ASD by 6-9%. By late adolescence, there was no difference in the amygdala
volume between those with ASD and those without. The growth in the volume occurs earlier in
children with ASD, and this may result in abnormalities in the neural organisation of the amygdala and
damage its functioning. This could help us to better understand the biological causes of ASD as we
could start measuring the amygdala to find an exact pattern, establishing a causal relationship
between amygdala growth and ASD. However, this may be difficult due to the cost and the ethical
issues that could be raised (such as informed consent, right to withdraw, and protection from harm).
The Amygdala Dysfunction Theory (Baron-Cohen (2000) argues that, as the amygdala has man
neural connections with the frontal cortex, abnormal development of the amygdala in childhood is a
major cause of the main social and behavioural deficits found in ASD. Those with ASD have
difficulties in understanding the expression of emotions in other people. Baron-Cohen investigated this
using the ‘eyes task.’ He used matched pairs to investigate the difference between brain activity in
people with ASD and people without. All participants were presented with photos showing the eyes of
people making facial expressions and asked each individual to identify the emotion; brain activity was
measured via MRI scans. He found that those with ASD performed worse than the control group. MRI
scans showed the left amygdala (involved when we infer emotional state from facial expressions) was
not activated in the participants with ASD but was strongly activated in the controls. This could help us
to better understand the biological causes of ASD as we can establish a pattern between those with
ASD and those without to find a common factor.
‘Briefly explain how biological explanations could be applied to modifying autistic spectrum
behaviours.’ (5)(2024)
Biological explanations could be applied to modifying autism spectrum disorder (ASD) behaviours
because if research suggests that amygdala dysfunction is a cause of ASD behaviours related to
social behaviours and emotional processing, then improving the function of the amygdala may help to
reduce these behaviours. For instance, intranasal oxytocin has been found to enter the brain
effectively and work to increase oxytocin levels in areas such as the limbic system, where the
amygdala is located. Some studies have shown that when people with ASD take intranasal oxytocin,
they show improved scores on tests of social behaviours. Therefore, the biological explanation of
amygdala dysfunction as a cause of ASD can be applied to modifying ASD behaviours.
‘Briefly evaluate one biological explanation of autistic spectrum behaviours.’ (5)(2021)
Firstly, one strength of the genetic explanation of autism spectrum disorder (ASD) is that it has
significant evidence that come with great findings that match the biological theory. For instance, Ritvo
et al (1985) found a concordance rate of 96% for identical (MZ) twins in ASD. MZ twins share 100% of
their genetics, showing that a 96% concordance rate is extremely high/similar. This is a strength of
this explanation of ASD as it highlights that those more genetically similar to others will have higher
chances of developing ASD if the other person also does. However, this study also suggests that we
cannot use genetics as the only explanation of ASD. If ASD was a genetic disorder, the concordance
rates for MZ twins must consistently be at 100%; Bailey et al (1995) also found a 92% concordance
rate. Therefore, we can use genetic explanations of ASD to develop our understanding of the potential
causes, but we cannot use it as the only explanation. We must acknowledge other explanations, for
example, individual differences.
‘Outline the characteristics of autistic spectrum behaviours.’ (10)(2018)
The characteristics of autism spectrum disorder (ASD) fall into impairments of two categories: social
communication/interaction and repetitive behaviour/restricted interests. For a diagnosis of ASD, the
individual must have impairments in both.
Social communication/interaction (SC/I) contains three elements: social-emotional reciprocity, non-
verbal communication, and developing and maintaining relationships. Those with ASD may struggle to
convey their interests and emotions; this can often result in an extreme reaction due to feeling
unheard. They can also find it difficult to initiate conversations, or alternatively, they can make
conversions one-sided about their own niche interests (e.g. dinosaurs, horses, monopoly, etc), or
respond to others inappropriately (licking, touching, etc). Non-verbal communication is when people
with ASD can rarely uses facial expressions or use them when they do not match the content of the
conversation. They can also have trouble interpreting the emotions of others by their non-verbal
communication (e.g. hand gestures, facial expressions). They can also sometimes sit too close or turn
their backs during a conversation with another person. Finally, they can struggle to see the world from
someone else’s perspective, being unaware of social norms, and finding it difficult to make
friends/build relationships with others compared to people without ASD.
Repetitive behaviour/restricted interests (RB/RI) contains 4 elements: repetitive behaviour patterns,
routines/rituals, and resistance to change, restricted/fixed interests, and usual reactions to sensory
input. Repetitive behaviour patterns includes doing one action again and again, for example, those
with ASD often displays echolalia, where they repeat what they hears from others (e.g. repeating a
quote from the TV). They can use extremely formal language (Little Professor Syndrome) or repetitive
hand gestures, like flapping. They often hold routines (e.g. lines dolls up in the same way every time),
with no variation, and overreactions to change in this routine. They often struggle to recognise
sarcasm and irony as they break the rules of ‘normal speech,’ for example, “its raining cats and dogs.”
Their restricted interests can create an intense preoccupation with a niche thing (e.g. dolls, cars), and
they often ignore others when they are occupied with them. Those with ASD are often either sensory
avoidant or sensory seeker. For example, sensory avoidant can be a resistance to touch (e.g. refusing
to brush their hair). Sensory seeker, for instance, can be where the individual can feel like they cannot
get enough of one stimulus (e.g. spinning around fast for extended periods of time).
For a diagnosis of ASD, symptoms are compared to a set criteria of the ASD manual, ICD-10 in the
UK and Europe, DSM-5 in the USA. The specialists evaluate their characteristics against the two
categories of SC/I and RB/RI, by ensuring that they have impairments in both categories for a
diagnosis. The diagnosis of ASD has 3 levels of severity in the DSM-5: high, medium, and low need
ASD. The ICD-10 still holds several types of ASD, childhood, atypical, low need, retts). If the individual
displays symptoms of ASD from both categories, they can be diagnosed with ASD.
Females being assessed for ASD can often face a hard, lengthy process of being diagnosed due to
their gender. This is due to the current diagnostic criteria for autism being developed using boys with
ASD. Girls’ neurodivergent brains are different to those of boys, so they are not always going to match
the criteria exactly. For instance, a girl’s restricted interest and obsession with dolls can be seen as
more of a ‘normal’ interest, as dolls are a common toy for female children; this could have slowed
down the diagnostic process due to this not being an abnormal issue. Girls are also more likely to be
misdiagnosed with obsessive compulsive disorder (OCD) prior to an ASD diagnosis, OCD, ADHD,
and anorexia instead of ASD, due to their cases being seen as less severe than boys’ as they do not
match the criteria precisely.
,“Deborah has recently been diagnosed with autistic spectrum behaviours.
Deborah's parents have noticed that her behaviour and linguistic patterns are different to other
children of her age.”
‘Describe how the characteristics of Deborah's behaviour would be different to other children.’
(15)(2021)
The characteristics of autism spectrum disorder (ASD) fall into impairments of two categories: social
communication/interaction and repetitive behaviour/restricted interests. Deborah’s diagnosis of ASD
was against a set criteria of these two categories, in the UK, it is called ICD-10.
Social communication/interaction (SC/I) contains three elements: social-emotional reciprocity, non-
verbal communication, and developing and maintaining relationships. Deborah struggles to convey
her interests and emotions; she can scream and cry when she feels unheard. She also finds it difficult
to initiate a conversation at school, or alternatively, she can make conversions one-sided about her
niche interests in dolls, or respond inappropriately (licking, touching, etc). Deborah’s parents have
noticed how her non-verbal communication is when Deborah rarely uses facial expressions or uses
them when they do not match the content of the conversation. Deborah also sometimes sits too close
or turns her back during a conversation with her teachers and parents. Finally, Deborah struggles to
see the world from someone else’s perspective, being unaware of social norms, and finding it difficult
to make friends at school compared to people without ASD.
Repetitive behaviour/restricted interests (RB/RI) contains 4 elements: repetitive behaviour patterns,
routines/rituals, and resistance to change, restricted/fixed interests, and usual reactions to sensory
input. Deborah often displays echolalia, when she repeats what she hears from the TV, or she can
use extremely formal language or repetitive hand gestures, like flapping. She lines her dolls up in the
same way every time, no variation to the way she plays with them, overreacting to change in this
routine. She struggles to recognise sarcasm and irony as they break the rules of ‘normal speech,’ for
example, “its raining cats and dogs.” Deborah has an intense preoccupation with a niche interest,
dolls, and she often ignores others when she is playing with them. Deborah is sensory avoidant to
touch; she often refuses to brush her hair as a result of this, sometimes having a panic attack.
However, she is a sensory seeker to movement, she can spend hours spinning really fast.
Deborah was diagnosed with ASD when her symptoms were compared to a set criteria of the ASD
manual, ICD-10, where she was diagnosed. The specialists evaluated her characteristics against the
two categories of SC/I and RB/RI, by ensuring that she had impairments in both categories for her
diagnosis. The diagnosis of ASD has 3 levels of severity in the ICD-10: high, medium, and low need
ASD. Deborah displays multiple symptoms of ASD, so she was diagnosed with high-need ASD. Her
“behaviour and linguistic patterns” are a main issue for Deborah, making SC/I the dominant
characteristics of her diagnosis, for example, non-verbal communication and social-emotional
reciprocity.
Deborah had a hard, lengthy process of being diagnosed due to her gender. This is due to the current
diagnostic criteria for autism being developed using boys with ASD. Girls’ neurodivergent brains are
different to those of boys, so they are not always going to match the criteria exactly. For instance,
Deborah’s obsession with dolls can be seen as more of a ‘normal’ interest, as dolls are a common toy
for female children; this could have slowed down her diagnostic process due to this not being an
abnormal issue. Deborah was misdiagnosed with obsessive compulsive disorder (OCD) prior to her
ASD diagnosis, due to her symptoms like routines/rituals and resistance to change. Girls are often
misdiagnosed with disorders like OCD, ADHD, and anorexia instead of ASD, due to their cases being
seen as less severe than boys’ as they do not match the criteria precisely.
‘Describe one biological explanation of autistic spectrum behaviours.’ (10)(2019)
One biological explanation for autism spectrum disorder (ASD) considers the role of the genetic
make-up of the individual in influencing their risk of developing an autistic spectrum disorder. This
explanation states that those with ASD have a genetic predisposition to the disorder and only 1% to
the general population. This would suggest that there is a genetic trend in the onset of ASD.
Family history studies are an efficient way of investigating genetic trends in ASD because they
evaluate the concordance rates between family members for ASD. For instance, evidence has shown
,a slight but significant trend for ASD to appear in siblings. Szatmari (1999) combined data from
several family studies to calculate the ‘sibling risk’. The risk was found to be 2.2%, which is significant
from the risk for someone with no siblings with ASD is 0.11%. This highlights that having a sibling with
ASD makes people 20x more likely to develop it themselves, demonstrating a genetic trend in ASD.
Therefore, family studies are valuable into investigating genetic trends in ASD as this study shows
that the likelihood of developing ASD is higher for people with a family history of it.
Similarly, twin studies are an effective way to investigate genetic trends in ASD as they analyse the
genes of identical (MZ) twins and non-identical (DZ) twins. For example, Ritvo et al (1985), found a
concordance rate of ASD of 96% in MZ twins and 23% in DZ twins. This shows genetic trends in ASD
as MZ twins share 100% of DNA, and DZ twins share 50%, and this is reflected in the concordance
rates, as for MZ twins, it is significantly higher. These rates are significant and is a good argument that
ASD is caused by genetics. It demonstrates that the closer individuals are genetically, the more likely
that they both will have ASD. However, due to the results not precisely matching their genetic
symmetry, we can not confidently conclude that ASD is purely caused by genetics, we must consider
other factors (for example, amygdala dysfunction, individual differences, etc).
Another way to examine the genetic trends in ASD is looking at simplex versus multiplex families.
Simplex families are when only one member is diagnosed with ASD/shows symptoms of ASD; this is
due to a new genetic mutation occurs during fertilisation. This mutation affects multiple genes, which
are called copy number variations (CNVs). CNVs account for 10% of all diagnosed cases of ASD, and
it more likely to happen if the parents are older (e.g. mother is 35+ at fertilisation). This highlights that
ASD can be caused by something going wrongly during fertilisation. On the other hand, multiplex
families are when multiple members have a diagnosis of ASD/show autistic traits. Multiplex families
show that ASD is likely to be caused by inherited genetic variations, suggesting that genes play a key
role in ASD. Therefore, these arguments both support the theory that genetics play a part in
developing ASD.
Finally, we can use non-syndromes versus syndromic diagnoses to evaluate the genetic role in ASD.
Non-syndromic diagnoses include ASD being diagnosed on its own; this shows that it is unclear what
the underlying genetic cause is as we can not find the specific gene, if there is one, causing the onset
of ASD. Whereas syndromic diagnoses of ASD include it being accompanied by another condition. If
the other condition has a well-established genetic cause, known as a single gene, it can help us to
understand the genetic causes of ASD further. For example, Fragile X Syndrome (FXS) is caused by
a mutation in the FMR1 gene; 60% of these cases also meet the diagnostic criteria for ASD. This
could help us to understand the genes involved with ASD, as the FMR1 gene could potentially be
involved.
‘Describe biological explanations of autistic spectrum disorders.’ (10)(2024)
One biological explanation for autism spectrum disorder (ASD) considers the role of the genetic
make-up of the individual in influencing their risk of developing an autistic spectrum disorder. This
explanation states that those with ASD have a genetic predisposition to the disorder and only 1% for
the general population. This would suggest that there is a genetic trend in the onset of ASD.
Twin studies are an effective way to investigate genetic trends in ASD as they analyse the genes of
identical (MZ) twins and non-identical (DZ) twins. For example, Ritvo et al (1985), found a
concordance rate of ASD of 96% in MZ twins and 23% in DZ twins. This shows genetic trends in ASD
as MZ twins share 100% of DNA, and DZ twins share 50%, and this is reflected in the concordance
rates, as for MZ twins, it is significantly higher. These rates are significant and is a good argument that
ASD is caused by genetics. It demonstrates that the closer individuals are genetically, the more likely
that they both will have ASD. However, due to the results not precisely matching their genetic
symmetry, we can not confidently conclude that ASD is purely caused by genetics, we must consider
other factors (for example, amygdala dysfunction, individual differences, etc).
We can also use non-syndromes versus syndromic diagnoses to evaluate the genetic role in ASD.
Non-syndromic diagnoses include ASD being diagnosed on its own; this shows that it is unclear what
the underlying genetic cause is as we can not find the specific gene, if there is one, causing the onset
of ASD. Whereas syndromic diagnoses of ASD include it being accompanied by another condition. If
the other condition has a well-established genetic cause, known as a single gene, it can help us to
, understand the genetic causes of ASD further. For example, Fragile X Syndrome (FXS) is caused by
a mutation in the FMR1 gene; 60% of these cases also meet the diagnostic criteria for ASD. This
could help us to understand the genes involved with ASD, as the FMR1 gene could potentially be
involved.
Amygdala dysfunction is another biological explanation of ASD as researchers have looked to the
brain for abnormalities in structure and function that may characterise those diagnosed with ASD. The
amygdala in particular is seen as significant due to its central role in regulating the behaviours that are
impacted in ASD.
Amygdala development in ASD was found to be faster in children with ASD compared to neurotypical
children. Nordahl et al (2012) found that from 2 years old, there is a larger growth in the amygdala
volume in children with ASD by 6-9%. By late adolescence, there was no difference in the amygdala
volume between those with ASD and those without. The growth in the volume occurs earlier in
children with ASD, and this may result in abnormalities in the neural organisation of the amygdala and
damage its functioning. This could help us to better understand the biological causes of ASD as we
could start measuring the amygdala to find an exact pattern, establishing a causal relationship
between amygdala growth and ASD. However, this may be difficult due to the cost and the ethical
issues that could be raised (such as informed consent, right to withdraw, and protection from harm).
The Amygdala Dysfunction Theory (Baron-Cohen (2000) argues that, as the amygdala has man
neural connections with the frontal cortex, abnormal development of the amygdala in childhood is a
major cause of the main social and behavioural deficits found in ASD. Those with ASD have
difficulties in understanding the expression of emotions in other people. Baron-Cohen investigated this
using the ‘eyes task.’ He used matched pairs to investigate the difference between brain activity in
people with ASD and people without. All participants were presented with photos showing the eyes of
people making facial expressions and asked each individual to identify the emotion; brain activity was
measured via MRI scans. He found that those with ASD performed worse than the control group. MRI
scans showed the left amygdala (involved when we infer emotional state from facial expressions) was
not activated in the participants with ASD but was strongly activated in the controls. This could help us
to better understand the biological causes of ASD as we can establish a pattern between those with
ASD and those without to find a common factor.
‘Briefly explain how biological explanations could be applied to modifying autistic spectrum
behaviours.’ (5)(2024)
Biological explanations could be applied to modifying autism spectrum disorder (ASD) behaviours
because if research suggests that amygdala dysfunction is a cause of ASD behaviours related to
social behaviours and emotional processing, then improving the function of the amygdala may help to
reduce these behaviours. For instance, intranasal oxytocin has been found to enter the brain
effectively and work to increase oxytocin levels in areas such as the limbic system, where the
amygdala is located. Some studies have shown that when people with ASD take intranasal oxytocin,
they show improved scores on tests of social behaviours. Therefore, the biological explanation of
amygdala dysfunction as a cause of ASD can be applied to modifying ASD behaviours.
‘Briefly evaluate one biological explanation of autistic spectrum behaviours.’ (5)(2021)
Firstly, one strength of the genetic explanation of autism spectrum disorder (ASD) is that it has
significant evidence that come with great findings that match the biological theory. For instance, Ritvo
et al (1985) found a concordance rate of 96% for identical (MZ) twins in ASD. MZ twins share 100% of
their genetics, showing that a 96% concordance rate is extremely high/similar. This is a strength of
this explanation of ASD as it highlights that those more genetically similar to others will have higher
chances of developing ASD if the other person also does. However, this study also suggests that we
cannot use genetics as the only explanation of ASD. If ASD was a genetic disorder, the concordance
rates for MZ twins must consistently be at 100%; Bailey et al (1995) also found a 92% concordance
rate. Therefore, we can use genetic explanations of ASD to develop our understanding of the potential
causes, but we cannot use it as the only explanation. We must acknowledge other explanations, for
example, individual differences.
