The Autism Spectrum and the brain Part 2

Our Information jigsaw And about: Fixed routine Repetitive behaviors Trouble with empathy New DSM-5 uses ASD instead of Autism, Asperger, and Pervasive Developmental Disorder Prevalence: 1 in 55 ASD is about: Overstimulation Motivated by various things Restricted interest High/low function along the spectrum Flat affect

Review - ASD Definitions Social Interaction Symptoms Communicate Symptoms Response to Sensory Other Behaviors Diagnosis 1 in 55 Mirror Neuron Prevalence

Outline Research Causes Mirror Neuron 2 Auditory experiments Treatments

Objectives - ASD Identify potential causes Recognize the main goal of the treatments Explain mirror neuron system Match the purposes of the studies to the challenges people with ASD encounter

Causes Caused by abnormally developing brain structure and function But WHAT causes the abnormal development? Scientists don’t know the exact causes of ASD

Potential Causes Genetic basis Environmental factors Both ASD: Identical > fraternal twins or siblings Higher chance: family members with ASD Mild symptoms: relatives of child with ASD Environmental factors Parental age Complication during birth ASD affects boys 3 - 4 times more often than girls

Potential Causes n Genetic basis q Both ASD: Identical > fraternal twins or siblings q Higher chance: family members with ASD q Mild symptoms: parents or relatives of child with ASD n Environmental factors q Parental age q Complication during birth n ASD affects boys 3 - 4 times more often than girls These potential causes are NOT triggering ASD, but increasing the risk of ASD There is no one single cause, but a combination of genetic and environmental factors that affect early brain development

Other suspected causes Chemical imbalance Viruses Problems in digestive tract There is no consensus on these causes Protective factor: prenatal vitamin – folic acid No link between childhood vaccination and Autism

Myths about ASD They don’t want friend Can’t feel or express any emotions Can’t understand others’ emotions They are intellectually disabled They are all like Rain Man They will have ASD forever It’s just a brain disorder (comorbidity) Caused by bad parenting Therapies are covered by insurance https://www.autismspeaks.org/node/113471

Treatments and Therapies Cannot be completely cured But they can: Make improvements Reduce the challenges in daily life Might be “test out” of ASD diagnosis

Goals of Early Intervention (under age of 3): Treatments and Therapies Goals of Early Intervention (under age of 3): Kids with ASD Parents Improve core behavior symptoms Build their strengths Learn new skills Remediate Resources Support Trainings: work and play with the child Receive counseling weakness Above age of 3 Special education service Adopted by The Individuals with Disabilities Education Act (IDEA) And by Wendy L. Stone, PhD & Theresa Foy DiGeromino, MEd

Treatments and Therapies n Early Intervention (under age of 3): q Involves the family and a team of professionals q Intensive q Highly structured q Constructive activities q Tailored to meet child’s needs and interests n Children with ASD can make great improvements from the intervention

The therapies include: Treatments and Therapies The therapies include: Applied Behavior Analysis (ABA) Occupational therapy Physical therapy Speech-language therapy Sensory integration and vision therapy Medications The best treatment plan: A combination of the therapies and techniques that is customized to meet the child’s needs

Applied Behavior Analysis (ABA) An discriminative stimulus (signal) Response / Prompt Positive reinforcement / Correction

Medications Treat associated behavioral or emotional problems, including: Aggression, Anxiety, Tantrums Attention problems Hyperactivity, Impulsiveness Irritability, Mood swings, Outbursts, Extreme compulsions that the child cannot stop Sleep difficulty

Brief summary Causes Treatments Abnormal brain development Genetic factor Environment factor Treatments Cannot be cure Focus on core behavioral symptoms E.g., ABA, occupational therapy, speech language therapy, medication

Research on ASD

Why do we study ASD? For the population: Rising prevalence Better educational environment Early diagnosis before 1yr Better treatment plan

Why do we study ASD? For research: How and why individuals with ASD perceive and interact with the world differently? Where do the exceptional skills come from? Understand how the brain works

Kim’s brain What brain structure is missing? corpus callosum What is the main function of this structure? Communicating between 2 hemispheres How does his brain compensate for the missing corpus callosum? The fibers travel elsewhere Forming peculiar connections

Brain Imaging Research Brain structure Anatomy Brain function Mirror Neuron Pitch perception Sound duration perception …

Mirror Neuron Important for: Action understanding Imitation learning Originally discovered in monkey’s premotor cortex Do a particular action Observe others (monkey/human) performing that same action See Review: Rizzolatti, G., & Craighero, L. (2004). The mirror-neuron system. Annu. Rev. Neurosci., 27, 169-192. Picture: https://sites.psu.edu/psych256su16-2/2016/06/28/mirror-neurons/

The mirror neuron system In human A set of brain regions Cortical areas related to motor Occipital, Temporal and Parietal Inferior frontal gyrus Motor cortex is activated Active movements Observe others’ movements Precentral gyrus Inferior parietal lobule A set of brain regions

Mirror Neuron Also plays a role in: Empathy: others’ emotions and sensations Understand intentions Imitation Language Overlap with the difficulties found in ASD

The Broken Mirror Theory of ASD More severe symptoms, less activation in mirror neuron system (Activity 13) The cortical areas of mirror neuron system are thinner in people with ASD The degree of thinning is correlated to the severity of the symptoms Caution! Using broken mirror theory to explain ASD is still over simplistic!

What can researchers in speech language hearing sciences do?

Pitch perception 12 individuals with ASD Remember that they are good at details 12 individuals with ASD 12 individuals as control group Listen to pure tones with different pitches Task: Discrimination: answer “same” or “different” Categorization: answer “high” or “low” Individuals with ASD had superior performance on both tasks Bonnel, A., Mottron, L., Peretz, I., Trudel, M., Gallun, E., & Bonnel, A. M. (2003). Enhanced pitch sensitivity in individuals with autism: a signal detection analysis. Journal of cognitive neuroscience, 15(2), 226-235.

Sound duration perception 15 children with ASD 15 children as control group Passively listen to speech or non-speech Long duration / high pitch They are good at details? Long duration / low pitch Short duration / high pitch Short duration / low pitch Individuals with ASD had superior performance on pitch, but impaired ability in duration Lepistö, T., Kujala, T., Vanhala, R., Alku, P., Huotilainen, M., & Näätänen, R. (2005). The discrimination of and orienting to speech and non-speech sounds in children with autism. Brain research, 1066(1), 147-157.

Summary We know more about ASD Research Potential causes Treatments Mirror neuron system Better at discriminateing pitch Poorer at discriminating sound duration