Mental illness Flashcards
What are the main impacts of autism spectrum disorders?
- troubles with social interaction
- troubles with communication
- restricted/repetitive behaviors
What is the incidence of ASD?
1%
What is the heritability of autism?
70%
What is the heritability of ASD?
90%
What are the developmental differences of people with ASD?
early brain overgrowth
What are the possible causes for early brain overgrowth in people with ASD?
- altered neuronal migration during gestation
- abnormal formation of synapses/dendritic spines
- overconnectivity of brain regions
- unbalanced excitatory-inhibitory neural networks
What is the main difference between the brain activity of ASD and non-ASD people?
ASD: little to no activity in the fusiform face area
What is the mode of action of anticonvulsants?
rises GABA receptor activityh
What is the mode of action of antidepressants?
heightens serotonin receptor activity
What is the mode of action of antipsychotics?
lowers dopamine receptor activity
What is the mode of action of stimulants?
heightens dopamine receptor activity
What is the main characteristic of major affective disorders?
disordered feelings
What are the two main mood disorders?
- bipolar disorder
- major depressive disorder
what is the prevalence of depression in women?
7%
What is the prevalence of depression in men?
3%
What is the percentage of risk od BD associated with genetics?
80%
What is the estimated prevalence of bipolar disorder in the population?
1%
How is mania characterized?
- unjustified euphoria
- incessant speech
- incessant motor activity
What is the treatment for bipolar disorder?
- lithium
- anticonvulsants
What is the effect of lithium?
- prevents mania, which means there is no onset of depression
What is the percentage of risk of MDD associated with genetics?
40%
What are the main characteristics of depression?
feelings of:\
- hopelessness
- guilt
- lack of worth of the self
WHat is the presumed mode of action of lithium?
decreases dopamine activity to reduce excitatory neurotransmission in the brain
What are the possible molecular treatments for MDD?
drugs that increase serotonine and/or neuropinephrine
What are the different types of molecules used in the treatment of MDD?
- SSRI
- SNRI
- tricyclic antidepressants
What is the mode of effect of tricyclic antidepressants?
- inhibits reuptake of serotonine and neuropinephrine
- affects most neuromodulators
What are the effects of SSRI?
inhibits reuptake of serotonineW
What are the effects of SNRI?
inhibit reuptake of serotonine and neuropinephrine
What areas are targeted by deep brain stimulation in the treatment of MDD?
- subgeneral anterior cingulate cortex
- nucleus accumbens
What areas are targeted by transcranial magnetic stimulation in the treatment of MDD?
pre-frontal cortex
What are the different treatments available for MDD?
- drugs that increase serotonin/neuropinephrine signaling by inhibiting their enzymatic breakdown/their reuptake
- ketamine
- electroconvulsive thrapy
- transcranial magnetic stimulaiton
- vagus nerve stimulation
- bright-light therapy
- sleep deprivation
What is the precursor molecule of serotonine?
triptophane
After succesful treatment, what tends to occur in the brain activity pattern of previously depressive people?
drop of activity in the anterior cingular cortex, an area situated in the prefrontal cortex
What is the monoamine hypothesis of depression?
Depression could be associated to insufficient monoamine receptor activity in the brain, especially dopamine and neuropinephrine
What is the main glucocorticoid of the human body?
cortisol
What are the two main physiological processes of stress?
- activation of the sympathetic system
- activation of the HPA axis
What is the result of the action of the HPA axis?
release of cortisol by the adrenal gland
What is the result of the activation of the sympathetic system by stress?
release of epinephrine and norepinephrine
What is CRH?
Corticotropin release hormone
What is the effect of CRH?
causes the pituitary gland to secrete ACTH
What is ACTH?
aadrenocorticotropic hormone
What is the main effect of the adrenocorticotropic hormone?
causes the adrenal gland to release glucocorticoids
What are the effects of glucocorticoids?
- make glucose and fat available for immediate use
- increase in blood flow
- supress secretion of sex hormones
- stimulates behavioral responsiveness
What are the effects of long-term stress on the brain?
- enlarged adrenal gland
- damaged hippocampus
- reduced size of the dorsomedial prefrontal cortex
What percentage of PTSD occurence is related to genetics?
30%
What are the possible treatments for PTSD?
- medication
- cognitive behavioral therapy
- group therapy
What are the physical elements/factors that can influence the occurence/effects of PTSD?
- abnormalies in the HPA axis
- increased amygdala activity
What are the classically observed symptoms of anxiety?
- muscle tension
- over activity of the autonomous nervous system
- expectation of impending disaster
- continuous vigilance for danger
What percentage of the population shows anxiety in any given year?
12%
What percentage of people develop social anxiety at some point in their life?
10%
What percentage of people develop a phobia in their life?
12%
What are the possible factors that increase chances of developing anxiety?
- environmental (absue, bad childhood, etc)
- genetic
- other mental disorders
- neurodegenerative diseases
What are the possible changes in brain activity assoicated with anxiety?
hyper activity of the amygdala and decreased activation of the ventrolateral prefrontal cortex
What are the symptom clusters of OCD?
1) hoarding
2) cleaning
3) symmetry
4) forbidden thoughts
What is the proportion of OCD due to genetics?
50%
What are the possible course of treatment for OCD?
- exposure/response prevention therapy
- antidepressants
- cingulectomy
- deep brain stimulation of the basal ganglia
What is a cingulectomy?
last resort treatment for OCD that consists in the severring of a nerve bundle between the anterior cingulate and the prefrontal cortex
What is particular about the brain activity of people with OCD?
- hyoeractivity in the prefrontal lobe
- hyperactivity in the striatum
Brain damage to which brain regions can cause the apparition of symptoms of OCD?
- basal ganglia
- cingulate gyrus
- prefrontal cortex
What percentage of the risk factors for alcoholism are accounted for by genetics?
40%-60%
What is the effect on brain signaling of reinforcement learning?
heightens dopamine signaling in the striatum, especially the nucleus accumbens
What disproves the negative reinforcement theory of addiction?
cravings and addictive behaviors outlast all withdrawal
What is the effect of past/active addition on the brain activity?
PFC hypoactivity
What disorders is addiction most frequently associated with?
- ADHD
- schizophrenia
What do ADHD, schizophrenia and addiction all have in common?
linked to abnormalities in the prefrontal cortex and its interationc with dopamine neurons and/or the striatum
What are the main approaches in the treatment of drug addiction?
- binding site blocker
- maintenance
- partial agonist
- brain stimulation
What are the different binding site blockers?
- naltrexone
- naloxon
What is the mode of action of naltrexon?
reduces the high created by opiates because it is an extremely hugh affinity opioid receptor antagonist
What is the mode of action of naloxom?
- opioid receptor antagonist
- reverses the effects of an opioid overdose
What molecules are used in the maintenance approach of the treatment of addiction?
- methadone
What is the mode of effect of methadone?
- potent opiate
- similar effect to heroin and morphine but with a slower onset and offset
- maintains addiction but allows the addict to be functionnal in society
What is the general mode of action of the molecules used in the partial agonists approach?
- will bind to the receptors
- produce an effect much smaller than that of the molecule
- prevents the drug from having any effect because the drug can no longer bind to its receptor
what type of drug prevention method does buprenophrine correspond to? which drug is it a treatment for?
- partial agonist approach
- opiates
What type of drug prevention method does varenicline correspond to? Which drug is it a treatment for?
- partial agonist approach
- nicotine
What areas are targeted by deep brain stimulation in the treatment of addiciton?
- PFC
- Basal ganglia
What area of the brain is targeted by treanscranial magnetic stimulation in the treatment of addiction?
PFC
What are the characteristics of ADHD?
- problems paying attention
- difficulty in inhibition
- hyperactivity
Which percentage of north american children is treated for ADHD?
more than 5 %
What is the heritability of ADHD?
75-90%
What are the factors that can influence the development of ADHD?
- alcohol use during pregnancy
- infections during pregnancy
- low birth weight
What are the types of molecules used in the management of ADHD?
- dopamine reuptake inhibitors or reversers
- antidepressants