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Encyclopedia of Nutritional Psychology

Fight-Flight-or-Freeze System

Evidence-informed definition Updated June 17, 2025 How to cite this entry

Fight-Flight-or-Freeze System or FFFS is one of the three systems regulating human behavior proposed by Gray’s reinforcement sensitivity theory. The functioning of the FFFS determines how prone a person is to experiencing fear. Strong activity in this system makes a person more likely to excessively avoid feared objects and develop conditions such as phobias and panic.

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Written by The Center for Nutritional Psychology
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The Center for Nutritional Psychology. (2025). Fight-Flight-or-Freeze System. In Encyclopedia of Nutritional Psychology. The Center for Nutritional Psychology.

https://www.nutritional-psychology.org/encyclopedia/fight-flight-or-freeze-system/
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