Fis phenomenon in sign language

Fis phenomenon is a classical phenomenon of child language acquisition that demonstrates a child's perception of language units that occur earlier than the ability of the child's phonological production.

The term "Fis" comes from a incident in 1960 by the U.S. psychologists Jean Berko Gleason (1931-) and Roger Brown (1925–1997). In this scenario, the child called his plastic fish a "fis". But, when the adult pronounced "fis", the child refused to accept the adult's pronunciation "fis" but accepted "fish" only.

This is also another illustration of the child's skills in comprehension that generally precedes skills in language production.

A similar "fis" phenomenon in American Sign Language with the toddler "Juli" was observed several times in the last few weeks with the ASL word "water". For example, one day Juli stood outside with her rocks in her hands and talked to me through the door window.

Juli produced ix-rock water ix-loc(hose) (with the "20" handshape error for "water"). I explained in ASL (translated as), "No, you cannot eat these rocks."

Juli realized that I interpreted her "water" production as "eat/food". She corrected herself and repeated water with the "W" handshape. I responded, "Ah, you want to use the water hose there?" Juli nodded.