Purpose: The production of formulaic expressions (conversational speech formulas, pause fillers, idioms, and other fixed expressions) is excessive in the left hemisphere and deficient in the right hemisphere and in subcortical stroke. Speakers with Alzheimer's disease (AD), having functional basal ganglia, reveal abnormally high proportions of formulaic language. Persons with Parkinson's disease (PD), having dysfunctional basal ganglia, were predicted to show impoverished formulaic expressions in contrast to speakers with AD. This study compared participants with PD, participants with AD, and healthy control (HC) participants on protocols probing production and comprehension of formulaic expressions. Method: Spontaneous speech samples were recorded from 16 individuals with PD, 12 individuals with AD, and 18 HC speakers. Structured tests were then administered as probes of comprehension. Results: The PD group had lower proportions of formulaic expressions compared with the AD and HC groups. Comprehension testing yielded opposite contrasts: participants with PD showed significantly higher performance compared with participants with AD and did not differ from HC participants. Conclusions: The finding that PD produced lower proportions of formulaic expressions compared with AD and HC supports the view that subcortical nuclei modulate the production of formulaic expressions. Contrasting results on formal testing of comprehension, whereby participants with AD performed significantly worse than participants with PD and HC participants, indicate differential effects on procedural and declarative knowledge associated with these neurological conditions. C linical descriptions of formulaic language in aphasic speech have flourished for more than 150 years under a wide variety of terms. Formulaic language, in its modern conception, consists of fixed, unitary expressions known to a language community with their characteristic form, meaning, and usage conditions. Typical examples are conversational speech formulas ("You betcha," "You've got to be kidding," and "Say what?"), expletives ("heck"), idioms ("as the crow flies," "That's the way the cookie crumbles"), proverbs ("When it rains, it pours"), and other conventionalized expressions ("all things being equal," "in the meantime," and "the long and the short of it is"; Altenberg, 1998;Biber, 2009;Kuiper, 2004;Wray, 2002). These expressions share the features of fixed or canonical form; conventionalized, often nonliteral meaning; and specific relations to discourse context.As reviewed in Van Lancker (1973, 1975, 1994, formulaic language has its venerable beginnings in observations by J. Hughlings Jackson (1874aJackson ( /1932Jackson ( , 1874bJackson ( /1932, who labeled the preserved expressions seen in adults with language disability following left-brain damage automatic or nonpropositional speech. Examples cited by Hughlings Jackson include phrases belonging classically to the conception of formulaic expressions: "Take care," "That's a lie," "Good bye," "Oh dear," and "Bles...

Background: Stimulation of the subthalamic nuclei (STN) is an effective treatment for Parkinson’s disease, but complaints of speech difficulties after surgery have been difficult to quantify. Speech measures do not convincingly account for such reports.Objective: This study examined STN stimulation effects on vowel production, in order to probe whether DBS affects articulatory posturing. The objective was to compare positioning during the initiation phase with the steady prolongation phase by measuring vowel spaces for three “corner” vowels at these two time frames.Methods: Vowel space was measured over the initial 0.25 sec of sustained productions of high front (/i/), high back (/u/) and low vowels (/a/), and again during a 2 sec segment at the midpoint. Eight right-handed male subjects with bilateral STN stimulation and seven age-matched male controls were studied based on their participation in a larger study that included functional imaging. Mean values: age = 57±4.6 yrs; PD duration = 12.3±2.7 yrs; duration of DBS = 25.6±21.2 mos, and UPDRS III speech score = 1.6±0.7. STN subjects were studied off medication at their therapeutic DBS settings and again with their stimulators off, counter-balanced order.Results: Vowel space was larger in the initiation phase compared to the midpoint for both the control and the STN subjects off stimulation. With stimulation on, however, the initial vowel space was significantly reduced to the area measured at the mid-point. For the three vowels, the acoustics were differentially affected, in accordance with expected effects of front versus back position in the vocal tract.Conclusions: STN stimulation appears to constrain initial articulatory gestures for vowel production, raising the possibility that articulatory positions normally used in speech are similarly constrained.