PSYCH 112 Lecture Notes - Lecture 13: Axon Hillock, Resting Potential, Acetylcholine
Document Summary
Neurons designed to turn energy into information. Neuron expend metabolic energy to create a chemical gradient. Caused by ejection of na+ and k+ ions, creating negative charge inside cell. Production of information from energy: chemicals tend naturally to form a continuous chemical gradient, movement of ions against this gradient requires metabolic energy, difference between internal and external polarity of the cell is a form of information. Active conduction: na+ ions rush into cell as depolarization causes ion gates to open. Passive conduction: the effect of myelinization: salutatory conduction, multiple sclerosis. Difference between the cell and its external environment is briefly reverse. Relative: next few milliseconds, until negative inner cell balance is fully restored. Neural activity involves differences in the neuron"s rate of firing. Continuous vs. discontinuous chemical gradient resting vs. action potential slow vs. rapid firing. Serotonin: involved in mood, sleep: ssris: selective serotonin reuptake inhibitors, marijuana and cocaine. A neuron"s rate of firing is a form of information.
