Just today a review article on voice and speech in PSP and the other atypical Parkinsonian disorders (APDs) appeared in the journal Movement Disorders – Clinical Practice.  The article is written for neurologists, but it should be comprehensible by educated laypersons, which is why I’m recommending it to you all.  

Two terms used in the article that are probably not familiar to you in this context are “spasticity” and “apraxia.” 

• Spastic speech has a “rubber-band” quality, with abrupt variations in speed and loudness. It’s very common in PSP. It corresponds to spastic limb movements (rare in PSP), where joints can suddenly flex or extend in response to gentle movement or sensory input.
• Apraxic speech features reduced ability to make certain sounds or words without a corresponding inability to form their components. It’s common in some of the APDs, but not in PSP. It corresponds to limb apraxia (common in PSP), where power and simple tasks are preserved, while more complex, learned tasks are impaired.

The paper includes videos of people with some of the APDs performing a standardized series of speech tasks, including describing the picture below:

The famous “cookie theft scene” test is designed to assess perception, judgement and language, but it serves as a test of voice and speech as well.  

That brings us to the differences among “voice,” “speech” and “language.” 

• Voice difficulties include things like hoarseness and low/high volume. 
• Speech difficulties include things like slurring, slowing/speeding and disordered rhythm of sentences. 
• Language problems include things like wordfinding problems, word substitutions and reduced grammatical ability.  It’s not discussed in the current paper but may be the topic of a subsequent review by the same group of neurologists. 

A quick-and-easy way to organize this scheme is to consider voice problems as arising from the lungs and larynx; speech problems from the mouth, tongue and lips; and language problems from the brain. 

The paper’s authors are all at institutions within CurePSP’s Centers of Care network.  The leader of the project was Dr. Federico Rodriguez-Porcel of the Medical University of South Carolina.  The other 25 authors, including yours truly, are listed in alphabetical order. So, as a clearly biased contributor, I recommend this paper on voice and speech in the APDs to those interested in understanding the range of such problems and their potential for rehabilitation.