PSYC1011 Lecture Notes - Lecture 4: Nernst Equation, Lipid Bilayer, Axon Hillock

• School: UNSW, UNSW Sydney
• Department: Psychology
• Course: PSYC1011
• Professor: All

Document Summary

Graded potentials: messages from the synapses travelling down the dendrites and cell body. Action potential or nerve impulse: signals down the axon, triggers the release of synapses, hence loop of communication. This example allows sodium to enter a cell (excitation) Other neurotransmitter/receptor combinations open chloride channels (inhibition: the excitation or inhibition of a cell is known as a post synaptic potential (or graded potential) Neurotransmitter reuptake: neurotransmitters are generally actively returned to the presynaptic cell. Graded potentials: neurons get information from other cells (at synapses), changing the electrical charge of the cell membrane, decreases in voltage are inhibitory postsynaptic potentials (ipsps) Increases in voltage are excitatory postsynaptic potentials (epsps: graded potentials epsps and ipsps move across the cell membrane towards the axon hillock. Information is summed so ipsps and epsps can cancel each other out. The action potential: an action potential will only fire once the threshold is reached at the axon hillock.