The frontal lobe contains most of the dopamine-sensitive neurons in the cerebral cortex. The dopamine system is associated with reward, attention, short-term memory tasks, planning, and motivation. Dopamine tends to limit and select sensory information arriving from the thalamus to the forebrain.
Na + concentration is lowered, indicating that Na + in-flux is responsible for the rising phase of the action po-tential. Their data also suggested that the falling phaseof the action potential was caused by a later increase inK+ permeability.
Generation of an Action Potential Across. Sarcolemma. Resting sarcolemma is polarized. Opening chemically gated ion channels upon ACh binding to ACh receptors allows. Na+ & K+ to pass the sarcolemma. More Na+ in than K+ out depolarization (interior slightly less negative.