PSYC 372 Lecture Notes - Lecture 3: Resting Potential, Sound, Axon Hillock
Document Summary
Ions: positively and negatively charged particles within neural tissue: sodium ions. In resting neurons, there are more na+ ions outside the cell than inside, and more k+ ions inside than outside. Ion channels: specialized pores in the neural membrane through which ions can pass: transporters: mechanisms within the membrane of a cell that actively transport ions of molecules across the membrane. Postsynaptic depolarizations are called excitatory postsynaptic potentials (epsps): they increase the likelihood that the neuron will fire. Postsynaptic hyperpolarizations are called inhibitory postsynaptic potentials (ipsps): they decrease the likelihood that the neuron will fire. Both espss and ipsps are graded responses: the amplitudes of each are proportional to the intensity of the signals that elicit them. Epsps and ipsps travel passively from their sites of generation at synapses, usually on the dendrites or cell body in much the same way that electrical signals travel through a cable. The transmission of postsynaptic potentials has two characteristics.