Exam 4 - Drugs and Behavior, Drugs, Behavior, and Major Depressive Disorder

Major Depressive Disorder (MDD)

Psychological disorder involving a major depressive episode and depressed characteristics, such as lethargy and hopelessness, for at least two weeks.

women, lgbt+, younger adults/elderly

demographics of who struggles with MDD more often

comorbidity

The coexistence of two or more disorders.

hypothalamus > posterior pituitary > adrenal gland > glucocorticoids

HPA activity; activates fight or flight response

monoamine theory

low levels of serotonin, dopamine, norepinephrine; lack of consistent data showing lower levels of monoamines in depressed populations

therapeutic lag

it takes a long time for a drug's effect to work

negative cognitive triad

negative views about the world, future, and oneself

neurogenic hypothesis

drugs may exert their effects by increasing growth and survival of newly formed neurons in the hippocampus

neurogenic theory of depression

theory that suggests that depression causes changes to brain anatomy

hyperactive HPA

impairs immune system and linked to hippocampal atrophy

brain-derived neurotrophic factor (BDNF)

a protein in the nervous system that promotes survival, growth, and the formation of new synapses

monoamine oxidase inhibitors (MAOI)

inhibits the enzyme that breaks down serotonin, dopamine, norepinephrine, etc.

tricyclic antidepressants (TCA)

blocks reuptake of serotonin and norepinephrine; blocks post synaptic acetylcholine, norepinephrine, and histamine receptors

selective serotonin reupatake inhibitors (SSRI)

blocks reuptake of serotonin

atypical/mixed action antidepressants (SNRIs)

most block reuptake of serotonin and norepinephrine

wine and cheese effect

tyramine build up; told not to eat dairy foods on MAOIs

tyramine

by-product of fermentation

TCA side effects

cardiotoxic - TCAs are lethal at doses commonly available to patients

serotonin discontinuation syndrome

another word for withdrawal; antidepressants can produce dependence but not addiction

fluelike symptoms, insomnia, nausea, imbalance, sensory disturbances, hyperarousal

FINISH symptoms

serotonin syndrome

high doses or when SSRI or other antidepressant combined with other serotonergic drugs

electroconvulsive therapy (ECT)

a treatment that involves inducing a mild seizure by delivering an electrical shock to the brain; developed based on the fault correlation that seizures effect severity

Classical Conditioned Tolerance

Tolerance developed through repeated drug exposure in same context.

Analgesia

Pain relief effect from morphine administration.

Paw Lick Latency

Time taken for a subject to lick paws after discomfort.

Behavioral Tolerance

Reduced response to a drug due to conditioning.

Heroin Overdose

Increased risk when used in unfamiliar environments.

Lethal Dose

Normal heroin dose: 200-400 mg; addicts: 1800 mg.

Drug Sensitization

Increased drug effects from repeated administration.

Reverse Tolerance

Increased effects observed after repeated drug use.

Incentive Sensitization Theory

Increased motivation to use drugs due to sensitization.

Placebo Effect

Therapeutic response from pharmacologically inactive substances.

Active Placebo

Produces some response but less than active drug.

Major Depressive Disorder

Mood disorder with increased prevalence in recent decades.

Monoamine Theory

Depression linked to serotonin, NE, and dopamine levels.

Neurogenic Theory

Depression as a reversible disorder affecting brain structure.

Hippocampal Atrophy

Reduction in hippocampal volume linked to chronic stress.

BDNF

Brain-derived neurotrophic factor crucial for neuron survival.

Corticotropin Releasing Factor (CRF)

Elevated in depressed patients, linked to stress response.

Neurogenesis

Formation of new neurons, particularly in the hippocampus.

Chronic Inflammation

Linked to depression, obesity, and gut bacteria imbalance.

Therapeutic Lag

Delay in drug effects, typically 2-4 weeks.

Double Blind Study

Neither participants nor researchers know treatment assignments.

Single Blind Study

Only researchers know treatment assignments.

Neural Adaptations

Changes in receptor sensitivity due to drug exposure.

Stress Response

Overactive HPA axis linked to depression and anxiety.

Causal Relationship

Depression can lead to alcohol use and vice versa.

Comorbidity

50% of depressed individuals also have anxiety disorders.

Electroconvulsive Therapy (ECT)

Effective for depression but may cause temporary memory loss.

Therapeutic Effects of Antidepressants

Increase serotonin, NE, and dopamine to alleviate symptoms.