PSYCH 250 Lecture Notes - Lecture 5: Myelin, Resting Potential, Saltatory Conduction
Video: Action Potential in Neurons notes
Thursday, February 13, 2020
2:13 PM
• Neurons
• Cells of the nervous system
• Use neurotransmitters to communicate with each other
• Can be long
o Dendrites
• Branches off the neurons; receive signals from other neurons
• Receive signals from other neurons via neurotransmitters
• When neurotransmitters bind to receptors on the dendrites, they
act like a chemical signal
• Binding opens ion channels that allows charged ions to flow in and
out; which converts the chemical signals to an electrical signal
• Each neuron can have many dendrites receiving input; if combined
effect of charges the overall charge of the cell enough, then it
triggers an action potential
o Soma/cell body
• Contains all of the neurons main organelles (i.e., the nucleus)
o Axon
• Wrapped in fatty myelin
• Where action potential travels
• Action potential
• Happens when overall charge of ions entering dendrite changes the overall
charge of the cell
• Neurons use action potentials to propagate signals within the cell
• Why does a cell have an electrical charge?
• The concentration of ions inside vs. outside of the cell
• When a neurotransmitter binds to a receptor on a dendrite, a ligand gated
ion channel opens to allow ions in
If there is a net positive charge: excitatory postsynaptic potential (EPSP);
depolarizing
