Pathological Demand Avoidance
(PDA):
exploring the behavioural profile & overlap
with ASD
Liz O’Nions, PhD Student
elizabeth.onions@kcl.ac.uk
Supervisors: Prof. Francesca Happé and Dr Essi Viding
MRC Social, Genetic and
Developmental Psychiatry Centre
Background
• PDA – proposed by Newson for children she
would have otherwise termed “atypical autism”.
• Inability to tolerate having anything imposed on
them, social strategies to avoid demands, driven
by need for control, outrageous behaviour.
• Equal gender ratio.
• Don’t respond to intervention approaches known
to work well in ASD
Background
• Not included in official diagnostic manuals
(DSM-IV/ ICD-10).
• Increasingly recognised in the UK – c. 300
clinicians/ professionals attended recent NAS
conference.
• No research.
• Poor prognosis – great parental concern,
particularly about managing adolescents/ adults.
Outline of the talk
• Part 1: Main features of PDA – anecdotal
descriptions.
• Part 2: Findings of a questionnaire study
exploring the behavioural profile in PDA,
compared to children with conduct problems/
callous unemotional traits and children with
ASD. Heritability analysis.
Part 1: What is PDA?
1. Resist ordinary demands using social
manipulation
2. “Superficial sociability” (e.g. no sense of
responsibility, acceptable behaviour, or social
boundaries)
3. Lability of mood & impulsivity
4. Pre-occupation with role play & pretend
5. Passive early history
Newson, Le Maréchal & David (2003) Arch Dis Child 2003;88:595-600
1. Avoiding demands
– Unable to comply with even simple requests.
– Becomes obvious when the child starts at
nursery – parents get used to handling the
child with “velvet gloves”.
Social nature of the demand is the problem.
1. Uses social manipulation to
avoid demands
Example of social manipulation from a
commentary by D. Tantam:
“Richard, for no apparent reason, seemed to target
one particular teacher at school. He made
slighting remarks about her at first, and then
became increasingly crude in his language until
she became so distressed that she said to the
head-teacher that either he went, or she did”
1. Uses social manipulation to
avoid demands
Avoidance tactics:
– rages or meltdowns
– repetitive questionning
– ignoring
– changing the subject, making excuses or threats
– slipping into a borrowed persona
– extreme behaviour (e.g. shouting swear words,
becoming violent, removing clothes, urinating on
the floor, dialling 999)
– praise and reproof don’t work.
2. ‘Superficial sociability’
Disinhibited/ socially inappropriate behaviour over
and above demand avoidance, are not put off by
others’ reactions.
Lack of sense of acceptable limits on behaviour Do not seem to realise that the rules apply to
them. May humiliate parents in public, call the
police, make false accusations etc.
2. ‘Superficial sociability’: social
relationships
Unable to negotiate with others their own age: see
themselves as an adult.
Bossy and domineering towards peers. Peers
perceive that they are infantile or are put off by
unpredictable and dis-inhibited behaviour.
Prefer 1:1 with adults, but only on their terms.
One sided/ controlling relationship with parents, but
do need them.
2. ‘Superficial sociability’: social
persona
May not seem socially unusual at first – gradually
becomes clear that their social persona is a
combination of roles.
Lack social understanding of their own but realise
that they should behave in a certain way and
able to copy.
 Social behaviour is “unsubtle or
ill-judged” – roles don’t blend in
– it is “learned behaviour”.
3. Lability of mood – led by
need to control
• Very extreme emotional
responses to small events.
• Sudden switches from loving to
aggression.
• Very impulsive & unpredictable
(e.g. prone to self injury/ attacking
others).
• Meltdowns and panic attacks
4. Role play
•
•
“Lives the part, not the usual pretence”.
Often used to avoid engaging socially/ as an
adaptation to social interaction.
• Some don’t seem aware of the distinction
between reality & fantasy.
In adulthood:
• 6/18 engaged in fantasy communications such
as poison pen letters, fantasy love letters, hoax
phone calls and letters.
5. Passive during infancy & other
characteristics.
• Passive, does not play with other children,
becomes “actively passive”.
• Language delay, but catch-up often rapid.
• “He only crawled when he thought no-one was
looking….”
Other
• Obsessions: centred on people or inappropriate
topics.
In adulthood (age 16-32: Newson et al., 2003)
• Parents concerned about aggression and
violence (to self and others)
• Social vulnerability (many are easily led or an
easy target)
• Their child’s sense of right and wrong.
Part 2: What do PDA look like on
child behaviour questionnaires?
• Questionnaire study: new data from parents of
children with PDA (aged 9-16yrs)
• Compared with existing data from parents of
5,000 12yr olds, where we identified:
– Conduct problems/ callous unemotional traits
(CP/CU; N=28)
– Autism Spectrum Disorders (ASD; N=39)
– Typical levels of key behaviours in >4,000 ‘TD’
children
Outcomes
• Severity of difficulties in PDA
• Nature of difficulties in PDA vs. ASD and
CP/CU
– Autistic-like behaviours
– Social interaction problems
– Difficult behaviour
– Anxiety
Autistic traits
• Score on “Childhood Autism Spectrum Test” for
PDA (& ASD) top 1% of distribution
Social interaction problems
• Similar to individuals with ASD – most affected 1%
Conduct problems/ CU traits
• Score on the Anti-Social Process Screening Device top
1% (like CP/CU).
Anxiety/ emotionality
• Score on the Anxiety/ emotionality subscale of the SDQ
in top 1% of population distribution (significantly higher
than ASD and CP/CU).
Twin study
Twin1
score
Twin 2
score
• Assigned a “PDA score” – a composite of
items.
• Were identical twins more similar in PDA
traits?
Heritability
• Substantial genetic influences, plus some
shared environmental effects.
Future directions
Research plans
 Experimental
research into PDA to investigate...
•ToM
•Emotion
recognition
•Empathy/
detachment
•Social
reward
Development of questionnaire to
measure PDA traits...
• The “Extreme Demand Avoidance”
Questionnaire developed with assistance of Phil
Christie.
• Currently collecting data on this and the SDQ
from parents of children aged 6-17.
• If you are a parent of a child with ASD/ ADHD
etc. or a typically developing child, please take
part in the study!
Acknowledgements
Supervisors: Francesca Happe & Essi Viding
ENC: Phil Christie, Dorinda Miller, Rukhsana Meherali, Kayleigh
Storey, Carrie Munroe
PDA website: Margaret Duncan
Clinicians: Lorna Wing, Judy Gould, Francesca Scanlon,
Rosalyn Proops, Betsy Brua, Liz Savage, Jacqueline Morgan.
KCL: Corina Greven, TEDS team
Parents: In particular Neville Starnes, Sam Parsons & Paula
Webb