Week 4 - ADHD and ASD Flashcards
Dopamine systems for ADHD
Mesocrticolimbic dopamine
Mesostriatal dopamine
VTA area
ADHD neurotransmitters
Dopamine
Noradrenaline - Locus Coeruleus - aplha and beta receptors
Less d and n
Noradrenaline and Dopamine
Control glutamate and gaba neurons in their terminal areas
ADHD - signal is noisy
What areas of the brain are eratic in ADHD
PFC and NA
How do ADHD treatments work?
enhance the amount of time that dopamine or noradrenaline is in the synaptic cleft - less eratic firinig
How do medications work?
Re-uptake (transporter) antagonists
Ritalin etc
How do dexamphetamine work?
Blocks dopamine and noradrenaline by reversing their function (stops uptake and also increases release of catecholamines via the transporter)
Other therapies - how does guanfacine and clonidine work?
Agonists at A2 receptors - activates noradrenaline neurons of locus coreclueus and directly acts on A2 receptors in PFC - creates EPSP
Neuropathology of ASD
Shorter cerebellum (PFC)
Increased density of smaller neurons in:
Amygdala
Cortex
Hippocampus
Epigenetics of ASD
Histones - positively charged proteins that interact and bind with the acid and negatively charged DNA molecule
How does Phenylketonuria cause ASD?
Inability to break P down to tyosine(maqke dopamine)
P inhibits myelination of neurons
What is the opiod excess theory?
Gluten and Caesin cross BBB if not metabloised and activate opiate receptors
Serotonergic dysfunction in ASD
Increased seratonion in periphery
High levels cause negative feedback (5hT1a) on seratonin cells and loss of terminals
Anxiety and obsessive behaviour treatment in ASD
SSRI’sA
Aggression treatment
Atypical antipsychotics
