sodium amytal test: anesthetize one hemisphere and check for language function; dichotic listening test: report more digits heard by dominant half; functional brain imaging: fMRI or PET used to see which half is active when performing a language test speech laterality and handedness sex differences in brain lateralization
A typical neuron has characteristic features: a cell body, dendrites and an axon. The axon projects from the cell body and makes contact with a target cell at the synapse. A neuron is stimulated by signals, chemical and electrical, to initiate an action potential (a rapid and reversible change in membrane potential). In the absence of a signal, the resting potential of the neuron is maintained by the potassium leak channels, which allow the flow of potassium ions out of the cell, resulting in a more negative charge in the cell when compared to outside the cell.
On the left is the action potential of an autorhythmic cell; on the right, the action potential of a contractile cell. Autorhythmic cells exhibit PACEMAKER POTENTIALS. Depolarization is due to the inward diffusion of calcium (not sodium as in nerve cell membranes). Depolarization begins when: 1  the slow calcium channels open (4), 2  then concludes (quickly) when the fast calcium channels open (0).