It is now time to meet the system that helps your brain stay in touch with the outside world. We follow up last week's tour of the central nervous system with a look at your peripheral nervous system, its afferent and efferent divisions, how it processes information, the reflex arc, and what your brain has to say about pain.

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Chapters:
Introduction: Peripheral Nervous System 00:00
Sensory Nerve Receptors: Thermoreceptors, Photoreceptors, Chemoreceptors, Mechanoreceptors, and Nociceptors 0:56
What is Pain? 1:54
How Pain is Processed 2:51
Pain Threshold vs Pain Tolerance 3:50
How the Brain Processes Pain 4:25
Afferent and Efferent Divisions 5:42
Five Steps of the Reflex Arc 6:38
What the Brain Says About Pain 8:09
Review 9:09
Credits 9:39

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