Mood disorders (MDD)

Major Depressive Disorder (MDD): Period of at least two weeks of low mood, loss of interest in activities, and other symptoms

Major Depressive Disorder (MDD) symptoms: Fatigue, No motivation, Cant imagine having fun, low sense of smell, impaired memory

(MDD) Sad vs Absence of happiness: Instead of being sad, its said that its an absence of happiness.

MDD Sleep: Have altered sleep cycles 

MDD Genetics: its moderately heritable (an Identical twins has more of a chance to get MDD if their twin has it then non fraternal twins)

MDD vs Allele: Those who have short alleles, are likelier to get a worse depression then those who have longer alleles after a major life stressor

Monoamine Hypothesis: Depression is caused by low level of activity of one

or more monoaminergic synapses (Dopamine, Serotonin, Norepinephrine)

What is the reason we know the Monoamine Hypothesis: Researchers gave depressed people different drugs until they found antidepressants (Trial and error)

Tricyclics (Antidepressants): Block transporter proteins that reabsorb serotonin, dopamine, and norepinephrine into the presynaptic neuron

Selective serotonin reuptake inhibitors (SSRIs) (Antidepressants): Block reuptake of serotonin

Serotonin norepinephrine reuptake inhibitors (SNRIs)(Antidepressants): Block reuptake of

serotonin and norepinephrine

Monoamine oxidase inhibitors (MAOIs) (Antidepressants): Block the

enzyme monoamine oxidase that metabolizes catecholamines and serotonin

into inactive forms (Stops the blocking of serotonin)

Brain-derived neurotrophic factor BDNF): a protein that plays a key role in

survival/growth of nerve cells in the CNS (people with depression have lower then average)

Transcranial Magnetic Stimulation (MDD Treatment): Pulses of magnetic energy focused over a particular surface along the scalp to deactivate neurons

Electroconvulsive therapy (ECT) (MDD Treatment): Electrically induced seizure used for the treatment of severe depression. (Memory loss)

Mania: restless activity, excitement, laughter, self-confidence, rambling

speech, and loss of inhibition

Bipolar Disorder (BPD): Characterized by alternating states of depression and mania

Bipolar Disorder (BPD) Genetics: High heritability, Childhood trauma increases BPD chance

Bipolar I: Goes from super manic to depressed

Bipolar II: Goes from Hypomania (Half way to mania) to depressed

Cyclothymia: Half manic to half depressed

Glucose in the brain of a BPD: Brain’s use of glucose increases during periods of mania and decreases during periods of depression.

Neurotransmitters: Depression: low serotonin and norepinephrine levels. Mania: elevated dopamine activity.

Lithium: Lithium stabilizes mood which is not known why however; it suppresses excitatory neurons (Dopamine and Glutamate) and enhances inhibitory neurons (Gaba)