Preliminary Voice and Speech Analysis Following Fetal Dopamine Transplants in 5 Individuals With Parkinson Disease


A surgical procedure involving transplantation of fetal dopamine cells into the striatum of persons with advanced Parkinson disease (PD) has recently been performed in an attempt to alleviate Parkinsonian and drug-dose related symptoms (e.g., the “on-off” phenomena). Improvements in limb motor and neurological function, as well as less severe and shorter on-off episodes have been reported following fetal cell transplant (FCT) surgery. Acoustic, electroglottographic, and perceptual measures were analyzed pre- and post-surgery to determine if phonatory and articulatory function were affected by this relatively new form of treatment. In addition, speech and motor exam measures were compared to determine if similar directional changes across motor systems were apparent. Findings suggest that FCT surgery did not systematically influence voice and speech production. Also, it appears that FCT surgery may differentially affect phonatory, articulatory, and limb motor systems. Findings are discussed relative to these differential effects.

The discovery that Parkinson disease (PD) is caused by a nigrostriatal dopamine deficiency has led to fairly successful management of this disease with L-dopa. However, problems, such as drug resistance and drug-dose related fluctuations, occur in some individuals after prolonged, continuous use (Barbeau, 1974; Marsden & Parkes, 1976). For this reason, neural transplantation of fetal dopamine tissue in PD has been pursued. The underlying principle of this procedure is that neural transplantation may replenish the dopamine deficiency by stimulating a steady and sustained release of this neurotransmitter or its precursors directly into the brain (Stein & Glasier, 1995)…