PSY 351 Chapter Notes - Chapter 3: Axon Hillock, Ion Channel, Cell Membrane
Document Summary
Chapter 3: the generation, transmission, and integration of neural signals. Tiny electoral charge to the brain can so dramatically affect the mind. A balance of electrochemical forces produces the resting potential of neurons. Ion: electrical charged molecules: anions: negatively charged ions. The membrane allow k^+ ions, but not na^+ ions, to enter/exit the cell fairly freely. The resting potential of a neuron provides a baseline level of polarization found in all cells. But unlike most other cells, neurons routinely undergo a brief bit radical change in polarization, sending an electrical signal from one end of the neuron to the other. A threshold amount of depolarization triggers an action potential: axon hillock: the cone-shaped area on the cell body from which the axon originates. 2 concepts are central to understanding how action potentials are triggered: hyperpolarization: an increase in membrane potential (that is, the neuron becomes even more negative on the inside. relative to the outside).
