Lexical diversity in Parkinson's disease.

Charles Ellis,Thomas West,Yolanda F Holt

doi:10.1186/s40734-015-0017-4

Charles Ellis, Thomas West + Show 1 more

Open Access

https://doi.org/10.1186/s40734-015-0017-4

Copy DOI

Abstract

BackgroundParkinson’s disease (PD) is a neurodegenerative syndrome of the basal ganglia (BG) believed to disrupt cortical-subcortical pathways critical to motor, cognitive and expressive language function. Recent studies have shown subtle deficits in expressive language performance among individuals with PD even in the earliest stage of the disease. The objective of this study was to use measures of lexical diversity to examine expressive language performance during discourse production in a sample of individuals with PD.MethodsTwelve individuals with idiopathic Parkinson’s disease (PD) were compared to twelve matched, neurologically intact controls on measures of lexical diversity. Three minute discourse samples describing a typical day were collected and analyzed for lexical diversity with the CHILDES program using measures of type token ratio (TTR) and voc-D (D).ResultsComparisons of three minute discourse samples indicated non-significant differences between individuals with PD and controls in word productivity (387 vs 356; p = .48). Similarly, there were also non-significant differences on measures of lexical diversity between the two groups (TTR = .45 vs.44; p = .50 and D 74 vs 68; p = .23).ConclusionsThese results suggest that lexical diversity during discourse production among individuals with PD is similar to non-neurological controls. These findings indicate that lexical diversity is an aspect of expressive language performance that is not impacted by the disease process in the earliest stages.

Highlights

Parkinson’s disease (PD) is a neurodegenerative syndrome of the basal ganglia (BG) believed to disrupt cortical-subcortical pathways critical to motor, cognitive and expressive language function
We examined subjects classified in Hoehn & Yahr (H&Y) stages II and III which are individuals with bilateral involvement yet are absent of significant motor impairment and are physically independent [23]
Motor speech performance ratings Group comparisons revealed a significant difference between the PD group (M = 2.2, SD .72) and control group (M = 1.3, SD .62) on intelligibility ratings, (X2 = 10.7; p = .003)

Summary

Introduction

Parkinson’s disease (PD) is a neurodegenerative syndrome of the basal ganglia (BG) believed to disrupt cortical-subcortical pathways critical to motor, cognitive and expressive language function. Recent studies have shown subtle deficits in expressive language performance among individuals with PD even in the earliest stage of the disease. The objective of this study was to use measures of lexical diversity to examine expressive language performance during discourse production in a sample of individuals with PD. Parkinson’s disease (PD) is a neurodegenerative syndrome most often associated with reductions in motor performance. In addition to motor deficits, many individuals with PD experience changes in cognitive and language skills. Expressive language deficits have been identified in PD, they are not reported as frequently as more commonly observed motor speech deficits

Objectives

Results

Conclusion