Acoustics of palilalia: A case study

Abstract

Palilalia is a rather rare speech disorder associated with a variety of etiologies including Parkinson's disease, stroke, epilepsy, and others. According to the literature, palilalia is characterized by repetitions of words, phrases, and/or sentences produced with an increasing rate and decreasing intensity. Because of the rare nature of this disorder, literature involving the characteristics is limited and somewhat contradictive. Although the original definition involves increasing rate and decreasing intensity, some researchers (i.e., Kent & Lapointe, 1982) have found different characteristics such as decreasing rate and increasing intensity when examining individual cases. This study adds to the literature regarding characteristics of palilalic speech in terms of change in rate and fundamental frequency from the original utterance to the first repeated train. This study utilized a single-subject design involving a 42 year old male who suffered an anoxic brain injury. Spontaneous speech samples were collected and analyzed. The results showed significant differences in terms of rate and fundamental frequency with the first repeated train in comparison to the original utterance. The rate was significantly faster and the fundamental frequency was significantly higher in the repeated utterance.