Mood disorders (MDD)

Major Depressive Disorder (MDD)

Period of at least two weeks of low mood, loss of interest in activities, and other symptoms.

MDD Symptoms

Fatigue, no motivation, can't imagine having fun, low sense of smell, impaired memory.

Sad vs Absence of Happiness

It's said that instead of being sad, MDD is characterized by an absence of happiness.

MDD Sleep

Has altered sleep cycles.

MDD Genetics

Moderately heritable; identical twins have a higher chance of MDD if their twin has it than non-fraternal twins.

MDD vs Allele

Those with short alleles are more likely to experience worse depression than those with longer alleles after a major life stressor.

Monoamine Hypothesis

Depression is caused by low levels of activity of one or more monoaminergic synapses (Dopamine, Serotonin, Norepinephrine).

Tricyclics

Antidepressants that block transporter proteins that reabsorb serotonin, dopamine, and norepinephrine into the presynaptic neuron.

Selective Serotonin Reuptake Inhibitors (SSRIs)

Antidepressants that block the reuptake of serotonin.

Serotonin Norepinephrine Reuptake Inhibitors (SNRIs)

Antidepressants that block the reuptake of serotonin and norepinephrine.

Monoamine Oxidase Inhibitors (MAOIs)

Antidepressants that block the enzyme monoamine oxidase, stopping the metabolism of catecholamines and serotonin into inactive forms.

Brain-Derived Neurotrophic Factor (BDNF)

A protein that plays a key role in the survival/growth of nerve cells in the CNS; lower levels are found in people with depression.

Transcranial Magnetic Stimulation

MDD treatment using pulses of magnetic energy focused over the scalp to deactivate neurons.

Electroconvulsive Therapy (ECT)

MDD treatment involving electrically induced seizures, often resulting in memory loss.

Mania

Characterized by restless activity, excitement, laughter, self-confidence, rambling speech, and loss of inhibition.

Bipolar Disorder (BPD)

Characterized by alternating states of depression and mania.

Bipolar I

Includes episodes of full-blown mania and depression.

Bipolar II

Characterized by episodes of hypomania and depression.

Cyclothymia

Characterized by periods of hypomania and mild depression.

Neurotransmitters in Depression

Low serotonin and norepinephrine levels.

Neurotransmitters in Mania

Elevated dopamine activity.

Lithium

Mood stabilizer that suppresses excitatory neurons (Dopamine and Glutamate) and enhances inhibitory neurons (GABA