Week 3 Lecture 3a - Disorders of Childhood (DN) Flashcards
To discuss the description, aetiology and treatment for developmental disorders, including autism, ADHD, and other externalizing problems.
Define the term Developmental Disorders.
- those conditions that are manifested in clinically significant ways during children’s developing years and are a source of concern to families and the educational system
What are three areas of controversy in the area of Developmental Psychology?
- The growing number of children diagnosed with a disorder
- The growing number of children on medication
- The change of reference for autism spectrum disorders in the DSM-5
4: 24
What is an important consideration when looking at the concept of normality or abnormality?
- context
- take into account the developmental period of the child
4:00
How was there a change of reference of Autism Spectrum Disorders in DSM-5?
- Changed in DSM-5
- Aspergers was separate
- Pervasive developmental disorders have all been put together
- Autism, Aspergers now put on a continuum
- Conduct & Oppositional Defiance moved into a separate category
7:15
What are two different ways that behaviours manifest in disordered children
- Externalising
- Internalising
- Social Withdrawal, Anxiety, Depression
How do boys and girls differ in their behavioural manifestation of childhood disorders?
- Girls - typically more internalising
- Boys - typically more externalising
10:30
When can a diagnosis of ADHD be made?
- Severe
- Persistent
- Problematic
“When hyperactive behaviours are extreme for the developmental period, persistent across conditions, and linked to significant impairments in functioning, the diagnosis of ADHD may be appropriate”
10:55
Give a conceptual understanding of the DSM-5 Criteria for ADHD?
6 or more behaviours listed under
- Inattention &/or
- Hyperactivity and Impulsivity
- typically manifests before age 12
- consistent across multiple settings
- reduce quality of functioning
- not exclusive during a psychotic disorder
- not better explained by another disorder
- there are three subtypes for diagnosis
(exam: think about the way this disorder manifests)
What are the three subtypes of ADHD?
- Predominantly Inattentive Subtype
- Predominantly Hyperactive Type
- Combined type
can switch between types
16:00
What are three characteristics of Attention-Deficit/Hyperactivity Disorder?
Inattention
Hyperactive
 Difficulty interacting with peers
What is the prevalence of ADHD?
- 3-7% of school-age children meet criteria
- Difficult to diagnose prior 4-5y
- ~4% adults ADHD
- (4.4% = Kessler et al., 2006; males, divorced, unemployed, non-hispanic white)
What did Hoza et al., 2010’s study look at, and what were the findings?
- looked at different aspects of childs behaviour
- the study followed children for 6 years
- found a viscious cycle of
- Social Skills (reduced)
- Aggression
- Inflated view of self
- these behaviours predicted poor outcomes
Why might it be difficult to diagnose ADHD prior to age 4-5yrs?
- diagnostic criteria requires 2 or more settings
- difficult as the child is not yet in school
- behaviour may be perceived as appropriate for that developmental age
What were some of the findings in Polanezyk et al., (2007) - which pooled estimates of prevalence worldwide (gender, age, geographical location?
- Males had higher prevalence (44 studies) than females (40 studies)
- consistent finding
- Male more likely to exhibit externalising
- Females - internalising
- yes there is a gender difference but must be
- More prevalent in children (43 studies) than adolescents (23 studies)
- Huge geographical differences in prevalence
- may be due to culture differences in what are considered normal/abnormal behaviour
- financial status of country
Does the comorbidity of externalising & internalising ADHD behaviours differ?
-
Externalising behaviours
- overlap with conduct disorders
-
Internalising behaviours
- overlap with Anxiety & Depression
- ~30%adolescents may have comorbid intellectual disability(Jensenetal.,1997)
What did Kessler (2006) show about adult ADHD & other disorders
- much more likely to have other comorbid disorders
- mood disorders
- anxiety disorders
- substance use disorders
- impulse control disorder
Kessler et al., 2006
22:00
What did the NIMH Multimodal Treatment Study of ADHD (MTA) illustrate?
What are the likely comorbid disorders with ADHD?
The overlap of co-occuring disorders
- ADHD alone - 31.8%
- Oppositional defiant disorder 39.9%
- Anxiety disorder - 38.7%
- Conduct disorder - 14.3%
- Tic Disorder - 10.9%
- Mood Disorder - 3.8%
n = 579
no need to memorise numbers for exam - just the disorders
23:00
What evidence points toward a genetic basis for ADHD?
What system is suspected to contribute to this disorder?
- Heritability estimates = ~70-80% (Thapar et al., 2007)
- suspected connection with Dopaminergic System
- Candidate Genes
- DRD4 (dopamine receptor gene)
- DAT1 (dopamine transporter)
- Move toward epigenetics
- Genetic*Environmental Studies Req’d
25:14
slide23
What paper published in the Lancet created controversy around ADHD?
- Williams et al., (2010)
- provided evidence that there was a genetic basis for ADHD & that it was not a purely social construct
- response of people (media backlash)
- because they said “direct evidence
- message of the paper was lost
Is there a neurobiological factor in ADHD?
- Structural Differences in ADHD
- ADHD =
- Smaller right PFC
- executive function, regulation, inhibition
- Smaller Caudate Nucleas
- Smaller Globus Pallidus E.g. Castellanos et al., 2002
- both parts of basal ganglia (involved in regulation, selection, initiation of behaviours)
STRUCTURE = FUNCTION
28:00
What behaviours are associated with Dopamine?
reward, gratification, attention
What neural differences exist in ADHD compared to a typical brain?
Neural Differences in ADHD
- Less activation in frontal areas during tasks
- Reduced striatal activation during inhibition tasks
Environmental Factors in ADHD?
- Low birth weight?
- Perinatal Factors inc. nicotine and alcohol
- 22% mothers of ADHD children smoked one pack/day
vs.
- 8% mothers of non-ADHD children smoked one pack/day
- Environmental Factors
- Food Preservatives? (not proven)
- Lead Paint? (no evidence)
causal no - contributory yes
30:00
slide27
What Pharmacological Treatments have been used for ADHD?
- Stimulants
- Most common – methylphenidate – prescribed since 1960s
- In 2006, 2.5 million US children taking stimulant medication (10% of all boys)
- Double-blind, placebo-controlled study. In 75% of ADHD children, stimulants:
- Reduce disruptive behaviour
- Improve Concentration
- Improve goal-directed activity
- Improve Classroom behaviour
- Improve social interactions
- Reduce aggression
- Reduce Impulsivity
34:00
