PSYC 375 Study Guide- Questions and 100% Correct Answers

How Neurons Integrate Information- Through dendritic spines, a neuron can establish more than 50,000 connections to other neurons - Nerve impulses traveling from other neurons bombard the receiving neuron with all manner of inputs (excitatory and inhibitory) - The cell body, located between the dendritic tree and its axon, can receive inputs from many other neurons Saltatory ConductionMyelin and Node of Ranvier Node of RanvierPart of an axon that is not covered by myelin Tiny gaps in the myelin sheath Enables saltatory conduction Excitatory postsynaptic potential (EPSP)Brief depolarization of a neuron membrane in response to stimulation, making the neuron more likely to produce an action potential Inhibitory postsynaptic potential (IPSP)Brief hyperpolarization of a neuron membrane in response to stimulation, making the neuron less likely to produce an action potential. Summations of InputsTemporal and Spatial Summations Temporal SummationPulses that occur at approximately the same time on a membrane are summed Spatial SummationPulses that occur at approximately the same location on a membrane are summed Voltage-Activated channels and the action potentialThe axon hillock (rich in voltage-activated channels) where the EPSPs and the IPSPs are integrated and where the action potentials are initiated Role of Ions in SummationThe influx and efflux of ions is what is being summed Versatile NeuronBECAUSE THE CELL BODY MEMBRANE DOES NOT CONTAIN VOLTAGE-SENSITIVE CHANNELS, A TYPICAL NEURON DOES NOT INITIATE ACTION POTENTIALS ON ITS DENDRITES.•IN SOME NEURONS, HOWEVER, VOLTAGE-SENSITIVE CHANNELS ON DENDRITES DO ENABLE ACTION POTENTIALS. Back propagationReverse movement of an action potential from the dendritic field of a neuron; postulated to play a role in plastic changes that underlie learning.