Neurons, Synapses, and Brain Lobes: Key Concepts for Psychology

Neurons

Nerve cells that send information.

Cell body

Contains nucleus.

Dendrites

Receive information.

Axon

Sends information.

Myelin

Covers some axons and helps messages travel faster.

Action Potential

The electrical message that travels down an axon.

All-or-none law

Signal is either sent or not sent; strength doesn't change; only frequency can change.

How Action Potentials Work

Sodium IN = neuron fires; Potassium OUT = neuron resets.

Resting potential

Approximately -70 mV.

Synapses

Gap between neurons where communication happens chemically.

Neurotransmitter

Chemical released by one neuron that is received by receptors of another neuron.

Parkinson's Disease

Caused by loss of dopamine-producing neurons.

Symptoms of Parkinson's Disease

Tremors, slow movement, difficulty starting movement, depression.

L-dopa

Treatment that helps increase dopamine levels.

Glutamate

Main excitatory transmitter.

GABA

Main inhibitory transmitter.

Acetylcholine

Involved in attention and arousal.

Dopamine

Involved in movement, motivation, and reward.

Serotonin

Involved in mood and emotion.

Norepinephrine

Involved in emotional memory.

Histamine

Involved in alertness.

Endorphins

Involved in pain relief and pleasure.

Agonist

Increases activity at synapse.

Antagonist

Decreases activity at synapse.

Stimulants

Drugs that increase energy and alertness.

Hallucinogens

Drugs that cause sensory distortions and altered emotions.

Depressants

Drugs that promote relaxation and lower anxiety.

Opiates/Narcotics

Drugs that provide pain relief and euphoria.

Marijuana

Contains THC, which reduces pain and nausea.

Monism

Brain activity and mental activity are inseparable.

Occipital Lobe

Responsible for vision.

Temporal Lobe

Responsible for hearing, language comprehension, and face recognition.

Parietal Lobe

Responsible for touch, pain, body awareness, and spatial awareness.

Frontal Lobe

Responsible for movement, decision making, attention, planning, and impulse control.