Neurons & Neurotransmission

These flashcards cover key concepts in neurons and neurotransmission, their functions, various neurotransmitters and their effects, as well as the impact of drugs on the brain.

What are the three primary functions of neurons?

Sensory (afferent), Motor (efferent), and Interneurons.

What does the Central Nervous System (CNS) consist of?

The brain and spinal cord.

What is the Peripheral Nervous System (PNS)?

Nerves branching out that allow communication with the CNS.

What are the two divisions of the Autonomic Nervous System?

Sympathetic and Parasympathetic divisions.

What is the role of the sympathetic nervous system?

Controls the body's response during perceived threat (fight-or-flight).

What is the role of the parasympathetic nervous system?

Controls the body's response while at rest (rest and digest).

What is myelin?

A fatty substance that coats the neuron and speeds up nerve transmission.

What is the function of dendrites in a neuron?

They receive incoming signals from nearby neurons.

What occurs during action potential in a neuron?

Sodium (Na+) rushes in, depolarizing the cell.

What is the all-or-none principle in neuron firing?

A neuron will either fire completely or not at all.

What occurs during the refractory period of a neuron?

The neuron cannot fire again until it has repolarized.

What is a neurotransmitter?

A chemical signal released at the axon terminal of a neuron.

What distinguishes excitatory from inhibitory neurotransmitters?

Excitatory neurotransmitters increase the likelihood of action potential; inhibitory decrease it.

What is GABA and its function?

An inhibitory neurotransmitter that helps regulate daily sleep-wake cycles.

What is dopamine's role in the brain?

Involved in pleasurable sensations and coordinated movement; it can be both excitatory and inhibitory.

What is the effect of the serotonin neurotransmitter?

Regulates moods, emotional states, digestion, and sleep.

What does the Acetylcholine (ACh) neurotransmitter do?

Stimulates muscle contractions and is involved in attention and learning.

What process occurs when neurotransmitters are reabsorbed?

Reuptake.

What is a drug agonist?

A drug that increases the bioavailability of a neurotransmitter.

What is a drug antagonist?

A drug that decreases the bioavailability of a neurotransmitter.

What can long-term drug use change in the brain?

It can change the neural pathways and lead to withdrawal symptoms if stopped suddenly.

What is meant by drug tolerance?

A reduction in response to a drug caused by repeated exposure.

What are depressants and stimulants?

Depressants slow CNS function (e.g., alcohol); stimulants speed up CNS activity (e.g., cocaine).

What constitutes a binge drinking episode for women?

4 or more drinks in about 2 hours.

What is harm reduction in the context of drug use?

Strategies aimed at reducing the negative consequences associated with drug use.