Functional fixedness is a cognitive bias that limits a person to using an object only in the way it is traditionally used.The concept of functional fixedness originated in Gestalt Psychology, a movement in psychology that emphasizes holistic processing.unctional fixedness is this inability to see a hammer's use as anything other than for pounding nails; the person couldn't think to use the hammer in a way other than in its conventional function. When tested, 5-year-old children show no signs of functional fixedness.