The name comes from an incident reported in 1960 by J. Berko and R. Brown, in which a child referred to his inflatable plastic fish as a fis.
In some cases, the sounds produced by the child are actually acoustically different, but not significantly enough for others to distinguish since the language in question does not make such contrasts.
The Fis Phenomenon occurs due to lack of production ability by the kid, though the child perceives the sound to be correct.
There is evidence to support the idea that a child manipulates isomorphic adult representations of language.
The role of perception in the phonological performance of children is that their lexical representation of the adult form is first passed through the child's perceptual filter.
An example of the implementation of Realization Rules is informally illustrated in the sample derivation below, where a child consistently produced squat as [gɔp]: /skwɒt/ → [skwɔp] (harmonizing a coronal to a preceding labialized sequence /kw/) [skwɔp] → [kwɔp] (deleting pre-consonantal /s/) [kwɔp] → [kɔp] (deleting post-consonantal sonorants)
[kɔp] → [gɔp] (neutralizing the voicing distinction)[6]Although children seem to be able to recognize the correct pronunciation of “fish”, they can only produce an /s/, meaning that they are left saying “fis” instead.
[8] Scoobie et al. in 1996 looked into the notion of child perception and how they acquire their speech as well as how children contrast minimal pairs.
[9] In a 1941 study by Roman Jakobson, he hypothesized that children who speak English basically follow a phonological order when acquiring their language's feature distinctions.
In a 1948 study, Schvachkin hypothesized that Russian-speaking children develop phonetic distinctions in an invariant order.
Juliette Blevins claimed that children can perceive both their own use of the language minimal pairs along with the adult usages.