Autism - Amygdala Dysfuntion Explanation For Autism

Question 1

Structure and functions of the amygdala

Answer 1

13 densely packed collections of cell bodies of neurones in each of the brains medial temporal cortex
One in each hemisphere
It is connected with other brain structures and regions
These connections give the amygdala a powerful influence on behaviours assoc w motivation, emotion and social interaction

Question 2

Amygdala development and ASD

Answer 2

Amygdala development differs w children with and without ASD
Christine Noradhl (2012) amygdala of children w ASD is 6-9% larger from 2 years of age
But as they get older volume growth stalls
May be responsible for abnormal neural organisation and impaired amygdala functioning

Question 3

Link between frontal cortex and amygdala

Answer 3

Amygdala is sometimes called the social brain as it has a central role in influencing social behaviour
Simon Baron - Cohen (2000) applied idea to ASD
Dysfunctional amygdala in childhood has profound effects on the operation of the frontal/ prefrontal cortex
Key cause of main social and behavioural deficits found in ASD including impairments of social- emotional reciprocity

Question 4

Role of amygdala in impaired social processing

Answer 4

People w ASD often don’t fully understand emotional expressions of others
Baron - Cohen (1999) showed it’s due to amygdala dysfunction impairing social processing
Presented pps w photographs of people making various facial expressions, showing the eye areas only
People w ASD found it hard to choose correct description from a choice of 2
fMRI scan showed relative to control participants, people with ASD had under-active left amygdala

Question 5

Research support AO3

Answer 5

Clinical study by David Kennedy (2009) studied famous case of SM
Didn’t have ASD but had a rare genetic disorder impairing amygdala function
Her preferred personal space distance for social interaction was half for matched control participants
She also experienced no fear at all
Supports theory as it shows amygdala dysfunction is assoc w social deficits similar to ASD

Question 6

Competing argument AO3

Answer 6

Findings of amygdala role are inconsistent
Martha Herbert (2003) reported smaller amygdala volumes in children w ASD compared with controls
Other research findings from various age groups differ
Casts doubts on validity of amygdala dysfunction theory and means precise role of amygdala is unclear

Question 7

Indirect not direct
AO3
Weakness

Answer 7

Weakness is link between ASD and amygdala dysfunction may be indirect
People w amygdala damage cannot process anxiety info normally so social functioning is impaired
Anxiety is a co-morbid feature of ASD
Susan White et al 2009 - suggests may be a link between amygdala dysfunction and social behavioural deficits that are outcome of abnormal processing of anxiety
Shows role of amygdala in ASD is more complex

Question 8

Oversimplification of neural factors
Weakness

Answer 8

Dysfunction explanation risks oversimplifying the brains role in ASD as several other Brain structures also are
Paul et al (2010) studied two women who has lesions to L & R amygdala. Damage was limited to the amygdala and didn’t affect surrounding areas
Women showed signs of impaired social behaviour but not to extent found in ASD (therefore amygdala dysfunction isn’t enough in its own)

Question 9

Application of treatment
AO3

Answer 9

Dysfunction explanation offers potential target for treatment
There is potential for drug based treatment that corrects amygdala functioning
If amygdala dysfunction is reliably linked to ASD it could lead to earlier diagnosis
Could shorten the very stressful diagnosis process