Relative fundamental frequency during vocal onset and offset in older speakers with and without Parkinson's disease

Abstract

The relative fundamental frequency (RFF) surrounding production of a voiceless consonant has previously been shown to be lower in speakers with hypokinetic dysarthria and Parkinson's disease (PD) relative to age/sex matched controls. Here RFF was calculated in 32 speakers with PD without overt hypokinetic dysarthria and 32 age and sex matched controls to better understand the relationships between RFF and PD progression, medication status, and sex. Results showed that RFF was statistically significantly lower in individuals with PD compared with healthy age-matched controls and was statistically significantly lower in individuals diagnosed at least 5 yrs prior to experimentation relative to individuals recorded less than 5 yrs past diagnosis. Contrary to previous trends, no effect of medication was found. However, a statistically significant effect of sex on offset RFF was shown, with lower values in males relative to females. Future work examining the physiological bases of RFF is warranted.

Comparison of voice relative fundamental frequency estimates derived from an accelerometer signal and low-pass filtered and unprocessed microphone signals

“…For the last cycle preceding the voiceless consonant (cycle 10 of the offset vowel) and the first cycle following the consonant (cycle 1 of the onset vowel), mean RFF values are À0.84 to 0.44 ST and 2.3 to 2.8 ST, respectively (Watson, 1998;Robb and Smith, 2002). However, for speakers with VH and PD, both offset and onset RFF tend to be lower compared to age-matched controls (Goberman and Blomgren, 2008;Stepp et al, 2010;Stepp, 2013). In individuals with VH prior to voice therapy (Stepp et al, 2010) and individuals with PD while off medication (Goberman and Blomgren, 2008;Stepp, 2013), mean RFF values for offset cycle 10 and onset cycle 1 are À1.0 to À2.2 ST and 1.8 to 2.7 ST, respectively.…”

“…Individuals with VH and PD are thought to have excessive laryngeal tension, i.e., higher baseline tension (Berardelli et al, 1983;Hillman et al, 1989;Roy et al, 1996;Gallena et al, 2001). Thus, their ability to use changes in tension during devoicing and revoicing may be limited due to a ceiling effect, and this decreased ability to modulate laryngeal tension could explain the lowered RFF seen in these individuals (Goberman and Blomgren, 2008;Stepp, 2013).…”

“…The difference in RFF between individuals with healthy voices and those with disordered voices (VH or PD) has been hypothesized to be caused by differences in baseline laryngeal tension (Goberman and Blomgren, 2008;Stepp, 2013). A previous study has shown that the activity of the cricothyroid muscle increases preceding or during the voiceless consonant and decreases immediately after (Lofqvist et al, 1989).…”

“…RFF has been of interest to a variety of different research studies (Watson, 1998;Robb and Smith, 2002;Goberman and Blomgren, 2008;Stepp et al, 2010;Stepp and Eadie, 2011;Stepp et al, 2012;Eadie and Stepp, 2013;Stepp, 2013). Several of these investigated the characteristics of RFF in populations with voice disorders, including vocal hyperfunction (VH) and Parkinson's disease (PD), and found that individuals with voice disorders have RFF that differs from those of individuals with healthy voices (Goberman and Blomgren, 2008;Stepp et al, 2010;Stepp et al, 2012;Stepp, 2013).…”

“…Several of these investigated the characteristics of RFF in populations with voice disorders, including vocal hyperfunction (VH) and Parkinson's disease (PD), and found that individuals with voice disorders have RFF that differs from those of individuals with healthy voices (Goberman and Blomgren, 2008;Stepp et al, 2010;Stepp et al, 2012;Stepp, 2013).…”