These are the abilities like memory span and mental speed that are related to physiological condition and maturation. They appear in childhood and can deteriorate with old age. See fluid crystallised intelligence theory.

FLUID ABILITIES: "Our fluid abilities can be lost with age."
Cite this page: N., Pam M.S., "FLUID ABILITIES," in PsychologyDictionary.org, May 11, 2013, https://psychologydictionary.org/fluid-abilities/ (accessed September 27, 2020).