A strident lisp results in a high-frequency whistle or hissing sound caused by stream passing between the tongue and the hard surface. In the extensions to the IPA, whistled sibilants are transcribed [s͎] and [z͎]. A palatal lisp is where the speaker attempts to make a sibilant while the middle of the tongue is in contact with the soft palate,[1] or with a posterior articulation of the sibilant.