Neurotransmission, Brain Chemistry, and the Endocrine System

Vocabulary flashcards covering neurotransmission steps, key neurotransmitters, agonists and antagonists, the endocrine system, autonomic nervous system branches, and key hormones.

Serotonin

A neurotransmitter involved in mood, appetite, dreaming, and sensory perception; an undersupply correlates with depression, anxiety, and aggression/anger.

Dopamine

A neurotransmitter released in response to feel-good behaviors that produces pleasure, governs movement, reinforces survival behaviors, and controls arousal and positive mood. Oversupply correlates with Schizophrenia, and undersupply with Parkinson’s.

Epinephrine

Also known as adrenaline, it acts as a neurotransmitter and a hormone and is part of the fight, flight, or freeze response.

Norepinephrine

A neurotransmitter affecting the central nervous system that plays a role in alertness and attention; low levels may result in ADHD.

GABA (gamma-aminobutyric acid)

An inhibitory neurotransmitter that makes it more difficult for neurons to fire, reducing energy levels and calming people down. Oversupply is linked to sedation, while undersupply is linked to seizures, tremors, and insomnia.

Glutamate

An excitatory neurotransmitter that makes it more likely for neurons to fire, increasing brain activity and energy levels. Oversupply can produce migraines or seizures, while undersupply can result in lethargy.

Agonist

Known as 'The Imposter,' a substance that mimics or boosts a neurotransmitter's action by acting like a fake key that fits and turns on a receptor lock to fire a biological response (e.g., Morphine).

Antagonist

Known as 'The Blocker,' a substance that blocks or reduces a neurotransmitter's action by acting like a broken key that jams the lock, stopping a biological response from happening (e.g., Naloxone / Narcan).

Endocrine System

A slow, chemical communication system consisting of glands that secrete hormones into the bloodstream.

Sympathetic Nervous System

The part of the nervous system responsible for the fight or flight response; it automatically accelerates heart rate and breathing, dilates pupils, and slows down digestion.

Parasympathetic Nervous System

The part of the nervous system responsible for 'rest and digest'; it automatically slows the body down after a stressful event.

Adrenaline

A hormone that prepares the body for emergencies as part of the fight or flight response.

Oxytocin

Known as the bonding hormone, it facilitates lactation and improves relationships.

Cortisol

Known as the stress hormone, it maintains homeostasis in the body.

Ghrelin / leptin

Hormones that trigger hunger, growth hormones, insulin release, and protect cardiovascular health.

Melatonin

A hormone primarily responsible for regulating the body's circadian rhythm (internal clock/sleep-wake cycles).

Pineal Gland

A gland that responds to light to regulate melatonin levels; exposure to more light results in less melatonin production.