Novel nonword learning in older speakers

Neeraja Sadagopan, Purdue University

Abstract

The primary aim was to characterize short- (within-experimental session) and longer-term (next day) speech motor learning in elderly individuals. Lip aperture coordination was assessed on two consecutive days for sixteen young and elderly participants during the production of six novel nonwords increasing in length and complexity. A measure of the consistency of interarticulator coordination was computed, and production duration was calculated for early and late trials across days for all nonwords. The effects of age on interarticulatory coordination as a function of nonword length and complexity were examined. Behaviorally, clear differences were noted between young and elderly participants in the ability to accurately produce the longer, more complex nonwords. Older speakers produced a significantly greater percentage of syllable errors than young adults for all four syllable nonwords, suggesting that important age-related differences are present for the processing and repetition of long, complex novel nonwords. Very few elderly individuals were able to produce the requisite number of accurate productions for kinematic analysis of the two most complex nonwords, and these were excluded from further statistical analyses. However, for the four performed nonwords that were included in the statistical analyses: (a) Elderly individuals demonstrated longer durations for nonword production than young adults, and this effect was magnified for longer, more complex nonwords, (b) No significant difference was noted between the two age groups in the ability to produce stable coordinative speech patterns, (c) Strong evidence for comparable overnight consolidation effects on speech motor learning in both young and older speakers is provided; lip aperture variability was lower on the second day of the experiment for both age groups, and (d) No short-term plasticity (within-experimental session) in the speech motor system was observed for novel nonword production in either age group. This experiment is the first investigation of the effects of age on novel nonword learning, and provides preliminary data for the investigation of speech motor learning of novel simple and complex productions in healthy older persons as well as in elderly individuals affected by neurological disease.

Degree

Ph.D.

Advisors

Smith, Purdue University.

Subject Area

Speech therapy

COinS