5. KPD patients show unusual speech patterns. This includes 1) a tendency to form words in the throat ("toe-tulee" (soft or swallowed L-sound)); 2) frequent use of words that convey no information. It is not unusual for KPD sufferers to make these words the most frequently used in every sentence; 3) an inability for even the apparently well educated to articulate thoughts coherently. An example of an utterance by a typical KPD sufferer: "Like, man, it was totally ya know, dude like, ya know?" Thus, an important element of the differential diagnosis is distinguishing KPD from some forms of mental retardation. When KPD was originally described, these traits were almost pathognomonic for the disease. Unfortunately, these patterns have spread to the general population so that the diagnostic value of the speech pattern trait is much diminished. However, because the speech patterns of the KPD-type in the general population are seen mostly prominently among the immediately post-pubescent, older patients with these patterns may well have KPD.
