1.3 The Neurons, Neurotransmitters, Hormones, and Psychoactive Drugs

This set contains terms from everything in the title. Includes what they do and key information about each.

Acetylcholine

A neurotransmitter that plays a key role in muscle activation, memory, and learning. It is involved in both the central and peripheral nervous systems.

Action Potential

A rapid change in electrical membrane potential that travels along the axon of a neuron, allowing the transmission of signals.

Addiction

A chronic condition characterized by compulsive substance use despite harmful consequences. It often leads to physical and psychological dependence on drugs.

Adrenaline

A hormone and neurotransmitter involved in the body's fight-or-flight response, increasing heart rate and energy availability.

Agonist

A substance that enhances or mimics the action of a neurotransmitter at a synapse, increasing its effect.

All-or-Nothing Principle

The fundamental concept that a neuron either fires completely or not at all, based on reaching a certain threshold of stimulation.

Antagonist

A substance that blocks or inhibits the action of a neurotransmitter at a synapse, decreasing its effect.

Cocaine

A powerful stimulant drug that increases dopamine levels in the brain, leading to heightened alertness and euphoria.

Depressant

A class of drugs that reduce neural activity and slow down body functions, often prescribed to relieve anxiety or promote sleep.

Dopamine

A neurotransmitter that plays a key role in pleasure, reward, and motor function.

Endorphins

Neurotransmitters produced by the body that help relieve pain and induce feelings of pleasure or euphoria.

GABA

A neurotransmitter that inhibits neural activity, contributing to the regulation of anxiety and muscle relaxation.

Ghrelin

A hormone produced in the stomach that stimulates appetite and increases food intake. Makes you hungry.

Glutamate

A neurotransmitter that plays a key role in synaptic plasticity, learning, and memory by facilitating excitatory signals in the brain.

Hallucinogen

A class of psychoactive substances that alter perception, mood, and cognitive processes, often causing hallucinations.

Heroin

A powerful opioid drug derived from morphine that is highly addictive and often used recreationally. It can produce intense euphoria but is associated with significant risks, including overdose and dependency.

Leptin

A hormone involved in regulating energy balance, appetite, and metabolism by signaling satiety to the brain.

Marijuana

A psychoactive drug made from the Cannabis plant, often used for its relaxing effects and ability to alter mood and perception.

Melatonin

A hormone that regulates sleep-wake cycles by signaling the body to prepare for sleep.

Motor Neurons

Neurons that convey signals from the central nervous system to muscles and glands, facilitating movement and reflexes.

Multiple Sclerosis

A chronic autoimmune disease that affects the central nervous system, damaging the myelin sheath of neurons and leading to various neurological symptoms.

Myasthenia Gravis

A chronic autoimmune disorder that causes weakness in the skeletal muscles by blocking communication between nerves and muscles.

Norepinephrine

A neurotransmitter involved in arousal, alertness, and stress responses, impacting mood and attention.

Opioids

A class of drugs that act on the opioid receptors in the brain, providing pain relief and producing feelings of euphoria. They can be both naturally derived and synthetic.

Oxytocin

A hormone and neurotransmitter that plays a significant role in social bonding, reproduction, and childbirth. It is often referred to as the "love hormone" due to its role in enhancing trust and emotional connections.

Reflex Arc

A neural pathway involved in reflex actions, typically consisting of a sensory neuron, an interneuron, and a motor neuron that facilitates quick responses to stimuli.

Refractory Period

The time following an action potential during which a neuron is unable to fire or requires a stronger stimulus to activate.

Reuptake Inhibitor

A type of drug that prevents the reabsorption of neurotransmitters in the brain, increasing their availability in the synaptic cleft and enhancing their effects on mood and behavior.

Sensory Neurons

A type of neuron that transmits sensory information from sensory receptors to the central nervous system.

Serotonin

A neurotransmitter that regulates mood, sleep, and appetite, often implicated in depression and anxiety.

Stimulant

A class of drugs that increase neural activity and enhance alertness, attention, and energy. Common examples include caffeine, nicotine, and amphetamines.

Substance P

A neuropeptide that functions as a neurotransmitter involved in the transmission of pain and inflammation signals in the body.

Tolerance

A physiological state where increasing doses of a substance are required to achieve the same effect due to repeated use.

Withdrawal

The set of symptoms that occur when a person reduces or stops using a substance after dependence has developed. Symptoms may include anxiety, irritability, and cravings.