Week 4 Flashcards
What is neurodevelopmental disorders?
a class of disorders that are commence
during childhood or prenatal development.
Include:
• Intellectual disability
• Communication Disorders (eg stuttering) • Autism Spectrum Disorder
• Learning Disorders (eg dyslexia)
• Attention-Deficit/Hyperactivity Disorder
Today we will just look at ASD and ADHD
Includes:
What is autism spectrum disorder?
Previously separated into several disorders including autistic disorder and Asperger’s disorder.
• Whilst there may be a range of severity, symptoms must be present in early development, and cause significant impairment in social and/or occupational functioning
Autism spectrum disorder is Persistent deficits in social communication and interaction,
including:
- Inability to engage in social emotional reciprocity
- Difficulty expressing and interpreting non-verbal behaviour
- Difficulty understanding and forming relationships
Autism spectrum disorder have Restricted, repetitive behaviours, interests or activities, demonstrated by at least two of the following:
- Stereotypes/repetitive motor movements, use of objects, or speech.
- Insistence of sameness, inflexibility, ritualized behaviour
- Narrow, fixated interests that are excessively intense
- Extreme sensitivity or limited sensitivity to environmental stimuli (eg indifference to pain, excessive touching of objects)
Autism spectrum disorder prevalence rate:
Prevalence: .6% -2% of children
4 x more common in males
- Appears to have a strong genetic component – Twin concordance rates range from 37% to 90%
- Pruning hypothesis - Lack of neuronal pruning during developmental periods?
Attention deficit hyperactivity disorder (ADHD):
A disorder that first appears in childhood and is characterised by the presence of inattention, impulsivity and hyperactivity that impacts on daily functioning and/or development. Symptoms must:
• Be age inappropriate
• Occur across multiple settings
• Of a level that impacts on social, academic and/or
occupational functioning
One half of diagnosing ADHD includes diagnosing inattention. Inattention diagnosis requires 6+ of the following for at least 6 months:
• Unable to pay close attention • Has problems sustaining attention • Doesn’t listen • Frequently fails to complete tasks • Inability to organise tasks/activities • Reluctant to engage in effortful mental tasks • Loses materials needed for tasks • Easily distracted • Forgetful in daily activities
One half of diagnosing ADHD includes diagnosing hyperactivity/impulsivity . Hyperactivity/impulsivity diagnosis requires 6+ of the following for at least 6 months:
• Restless – frequently fidgets/squirms
• Leaves seat in situations where expected to stay seated
• Runs/climbs in situations that are inappropriate
• Unable to play in a quiet manner
• Often ‘on the go’
• Talks excessively
• Blurts answers/interrupts before the other person has stopped
talking
• Difficulty waiting turn
• Interrupts or intrudes on others
Prevalence rate of ADHD
- Prevalence in Australia estimated at 2.3-6% of school-aged children.
- ADHD 5-9 times more common in males than females.
- Persists into adulthood – but hyperactivity symptoms decline, inattention remains.
- Appears to be a genetic link – ADHD does run in families through generations.
- Evidence that low birth weight or maternal smoking (during pregnancy) increases risk of ADHD
Neurocognitive disorders:
class of disorders in which the predominant symptom is cognitive impairment (deficits in memory, learning, thought).
Some common causes are:
- Advanced Age (eg Alzheimer’s Disease)
- Illness (eg HIV related dementia)
- Injury (eg Traumatic Brain Injury)
- Genetics (eg Huntington’s Disease)
What is the difference between dementia and Alzheimer’s disease?
Dementia – an umbrella term that covers a range of disorders in which there is a steady, usually irreversible, pattern of cognitive decline. Can affect memory, language, thought, behaviour.
- Whilst some forms are treatable (eg those due to infection), most are irreversible (eg Alzheimer’s Disease)
- Onset is typically insidious (proceeding gradually)
So, Alzheimer’s disease is one of a number of types of dementia.
Alzheimer’s disease:
Degenerative brain disorder that involves progressive cognitive decline. Culminates in widespread cognitive failure and death.
Neurofibrillary Tangles: Threads of protein that occur within a neuron.
Senile Plaques (aka Amyloid Plaques): Deposits caused by debris from degenerating neurons and build-up of protein
AD is the most commonly diagnosed form of dementia, but technically can only be confirmed post mortem, so classified as either:
- Probable Alzheimer’s Disease if there is a family history and/or there is significant cognitive decline.
- Possible Alzheimer’s Disease if there is no family history, but there is steady cognitive decline which cannot be explained by other medical history
Prevalence rate of Alzheimer’s disease:
Prevalence: 13% in 65 + 42% in 85 +
- Average lifespan following diagnosis = 10 years
- Tends to be more frequent in females (even after longevity differences between sexes is accounted for)
- AD is characterised by the presence of neurofibrillary tangles, senile (aka amyloid) plaques and neuron loss, typically concentrated in specific regions of the brain.
Alzheimer’s disease progression - neuroanatomical
- The damage associated with AD usually commences in specific brain regions, then spreads in a predicable pattern.
- We can therefore predict in many cases what functions will become impaired during the progression of the disease
Alzheimer’s disease progression : cognitive
• Often starts with general confusion and irritability, speech deficits.
• As the condition progresses the memory impairments become increasingly noticeable.
• Memory loss follows pattern of structural deterioration.
• Occurs in all types of memory –
- Episodic (memory of events that have happened)
- Semantic (general knowledge)
- Procedural (how to make a cup of tea)
• Recent memories are first to be lost, and there is a chronological progression backwards:
Eg – forget grandchildren’s names, then children’s, then partners, then siblings etc.
As well as memory decline, there is a number of other changes which come with the progression of Alzheimer’s disease:
- Mood – depression often see in early stages
- Mood – can become combative/argumentative
- Language impairment
- Restlessness/Motor agitation
- Motor impairment – eg difficulty walking
- Psychosis
- Lose social inhibitions