AP Psych: Unit 1.3- The Neuron and Neural Firing

Based on AP Course Guide

Neurons

Nerve Cells, building blocks of the nervous system, many different types

Glial Cells

Helper cells that send and receive chemical signals to and from each other and neurons

Sensory neuron

Involved in sensation/senses, different for each sense, respond to non-chemical stimulation, send inward signals that arrive @ brain

Motor Neurons

Involved in reflexes and movement, connected to all of our muscles, can react to involuntary and voluntary signals, send signals that exit brain

Interneuron

Sends signals between sensory and motor neurons

Receptor site

Receives a sensation (sensory neuron)

Jobs of neurons

receive, carry, and send messages

Soma

Cell body, includes nucleus, keeps nucleus healthy

Dendrites

Receive signals entering a neuron

Axon

Tube that action potentials go down

Myelin Sheath

A fatty substance that protects and insulates axons

Axon Terminal

The end of the neuron, where information is passed to other dendrites

Synaptic Gap

The place where neurotransmitters cross and lock into the dendrite of the postsynaptic neuron

Action Potential

The electric impulse that travels down the length of an axon

Excitatory Neurotransmitters

Make the next neuron more likely to fire

Inhibitory Neurotransmitters

Make the next neuron less likely to fire

Resting Potential

The point at which a neuron is not active (polarized)

Firing Threshold

The certain threshold at which a neuron will fire

All or None Law

Once at threshold, the neuron will fire and at the same intensity each time

Depolarization

The point during the action potential when the neuron’s charge becomes positive

Refractory Period

A brief period where the neuron can’t fire again

Reuptake

The sending neuron recollects neurotransmitters

Neurotransmitters

Chemical messengers of the nervous sytem

Glutamate

Most abundant excitatory neurotransmitters, enhances learning and memory by strengthening synaptic connections

GABA

Most abundant inhibitory neurotransmitter that is associated with various anxiety disorders

Acetylcholine

Found in both central and peripheral nervous systems, involved in movement, learning, and memory

Dopamine

Linked to pleasurable and rewarding activities, as well as movement, attention, and learning

Endorphins

Associated with pain reduction, can be stimulated by prolonged exercise

Epinephrine (Adrenaline)

Both a neurotransmitter and hormone, boosts energy and is involved in fight or flight responses

Norepinephrine (Noradrenaline)

Neurotransmitter involved in arousal, alertness, and heightened sensitivity to what is going on around you, heavily associated with sleep wake cycle

Serotonin

Neurotransmitter that plays a role in mood, appetite, and sleep

Agonists

Bind with the neurotransmitter at the synapse to increase neural firing

Antagonists

Binds with a neurotransmitter in a way that decreases neural firing by blocking the neurotransmitter at the synapse

Heroin

An agonist for endorphins

Nicotine

An agonist for acetylcholine, stimulates skeletal muscles and causes increased heart rate

Black Widow Venom

An agonist for acetylcholine, toxin that can lead to death

Reuptake Inhibitors

Drug or chemical introduced at synapse that blocks reuptake channels

Prozac

Inhibits reuptake of serotonin, flooding the synapse with serotonin

Cocaine

Inhibits reuptake of dopamine, flooding the synapse with dopamine (agonist for dopamine), while elevating serotonin and norepinephrine, stimulant, intense euphoria, alertness, heightened self confidence

Botox

A toxin that freezes muscles from firing so wrinkles don’t form, antagonist for acetylcholine

Thorazine

An early drug for schizophrenia that is an antagonist for dopamine

Psychoactive drugs

Alter mental states and activate dopamine-producing neurons in the brain’s reward system

Tolerance

Needing increasing amounts of the drug to create the desired effect

Blood-Brain Barrier

A semi-permeable barrier that allows some chemicals to pass into the brain but prevents other from passing into the brain, all psychoactive drugs can pass this barried

Depressants

Slow or inhibit CNS functions, relieve anxiety and create drowsiness, combining different ones can be deadly

Opioids

Agonists for endorphins, incredibly effective and create powerful withdrawal symptoms

Stimulants

Activate sympathetic nervous system functions, increase brain activity and mental alertness

Hallucinogens

Create sensory and perceptual distortions, alter mood, and affect thinking

Alcohol

Agonist for GABA, net slowing effect on CNS functions

Caffeine

Promote wakefulness, mental alertness, and faster thought processes by stimulating dopamine release, antagonist for adenosine, blocks sleep-inducing effects

THC

Mild hallucinogen, produces sense of well-being, mild euphoria, dreamy state of relaxation, in marijuana, interferes with muscle coordination, learning, memory, and overall cognitive functions, various therapeutic uses