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Nerve Regulation of the Heart

5 videos
Although your heart can beat independently, your nervous system is important as an external regulator. Your brain can tell your heart to speed up or slow down, depending on the scenario. For example, when you’re falling asleep, your nervous system will cause your heart to slow down, and 8 hours later when your phone alarm goes off, your nervous system will speed up your heartbeat! So even though your heart muscle beats by itself, the nerves can ramp up or down the speed. Check out the videos to learn more about how the nerves help to regulate the heart.

Changing the AV node delay - chronotropic effect

VIDEO 12:14 minutes
Find out exactly how your autonomic nervous system has a chronotropic effect (i.e. timing) that changes the delay between the contraction of the atria and the ventricles! Rishi is a pediatric infectious disease physician and works at Khan ...

Changing the heart rate - chronotropic effect

VIDEO 12:02 minutes
Find out exactly how your autonomic nervous system has a chronotropic effect (i.e. timing) that changes speed of your heartbeat! Rishi is a pediatric infectious disease physician and works at Khan Academy.

Increasing ventricular contractility - inotropic effect

VIDEO 10:25 minutes
Find out how the sympathetic nerves increase the heart's force of contraction and speed of relaxation! Rishi is a pediatric infectious disease physician and works at Khan Academy.

Autonomic nervous system effects on the heart

VIDEO 6:16 minutes
Carefully go through each of the four major effects that the sympathetic and parasympathetic system has on your heart: Chronotropy, Dromotropy, Inotropy, and Lusitropy. Rishi is a pediatric infectious disease physician and works at Khan ...

Getting a new heart

VIDEO 7:26 minutes
Think through the result of getting a new heart, and how the heart can still maintain homeostasis when the nerves are no longer around. Rishi is a pediatric infectious disease physician and works at Khan Academy.