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Stimulus

A stimulus is anything that can trigger a physical or behavioral change. The plural of stimulus is stimuli.

Stimuli can be external or internal.

An example of external stimuli is your body responding to a medicine.

An example of an internal stimulus is your vital signs changing due to a change in the body.

Stimuli include:

  • Irritants
  • Sights
  • Smells
  • Sounds
  • Temperature changes

References

Taber's Cyclopedic Medical Dictionary. 24th ed. Philadelphia, PA: F.A. Davis Company; 2021. www.tabers.com/tabersonline/view/Tabers-Dictionary/745052/all/stimulus. Accessed December 17, 2024.

Review Date 1/1/2025

Updated by: Linda J. Vorvick, MD, Clinical Professor Emeritus, Department of Family Medicine, UW Medicine, School of Medicine, University of Washington, Seattle, WA. Also reviewed by David C. Dugdale, MD, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.