Nervous system Quote by Robert M. Sapolsky
““Meanwhile, the parasympathetic nervous system (PNS) arises from different midbrain/brain-stem nuclei that project down the spine to the body. In contrast to the SNS and the four Fs, the PNS is about calm, vegetative states. The SNS speeds up the heart; the PNS slows it down. The PNS promotes digestion; the SNS inhibits it (which makes sense—if you’re running for your life, avoiding being someone’s lunch, don’t waste energy digesting breakfast).””
About This Quote
Source Book: Why Zebras Don't Get Ulcers, Robert M. Sapolsky, 1994
The parasympathetic nervous system calms the body, slowing heart rate and aiding digestion, opposite to the fight‑or‑flight response of the sympathetic system.
In simple terms: PNS calms; SNS excites.
Key Takeaway
Balance nervous system activity.
Themes
biologyiology
physiology
stress management
Mood
calm
reflective
Type
educational
informative
When to use this quote
- medical education
- personal health
- stress reduction
- exercise recovery
Key Concepts
autonomic nervous system
homeostasis
fight or flight
Questions to Reflect On
- How can you consciously activate your PNS during stress?
- What daily habits support parasympathetic tone?
A Different Perspective
PNS effects can be subtle and overlooked in fast‑paced life.
![“It was at Harvard not quite forty years ago that I went into an anechoic [totally silent] chamber not expecting in that silent room to hear two sounds: one high, my nervous system in operation, one low, my blood in circulation. The reason I did not expect to hear those two sounds was that they…” quote by John Cage](https://sms4smile.com/quotes/img-quotes/153/john-cage-2094_blood_it-was-at-harvard-not-quite-forty-years_56114.jpg)
