PSYCH261 Chapter 1.2:

• School: University of Waterloo
• Department: Psychology
• Course: PSYCH261
• Professor: Daniel Smilek

Document Summary

The resting potential of the neuron: all neurons are covered by membrane composed of 2 layers of phospholipid molecules, embedded among phospholipids are cylindrical protein molecules thru which various chemicals can pass. Why a resting potential: body invests a lot of energy to operate na+-k- pump which maintains resting potential, why is it worth so much energy, resting potential prepares neuron to respond rapidly. Stimulation beyond threshold of excitation produces massive depolarization of membrane: when potential reaches threshold, membrane opens na+ channel and allows na+ to flow into cell. T: any subthreshold stimulation produces a small response that quickly delays, any stimulation beyond threshold produces big response = ap, peak of ap = +30 mv (varies from one axon to another) Local anesthetic drugs attach to na+ channel preventing na+ from entering and thus stopping ap. Propagation of the action potential: describes the transmission of an ap down an axon, during ap, na+ enter a pt on axon.