How Much Time Do People With Aphasia Need to Respond During Picture Naming? Estimating Optimal Response Time Cutoffs Using a Multinomial Ex-Gaussian Approach
- 26 February 2020
- journal article
- research article
- Published by American Speech Language Hearing Association in Journal of Speech, Language, and Hearing Research
- Vol. 63 (2), 599-614
- https://doi.org/10.1044/2019_jslhr-19-00255
Abstract
Purpose Aphasia is a language disorder caused by acquired brain injury, which generally involves difficulty naming objects. Naming ability is assessed by measuring picture naming, and models of naming performance have mostly focused on accuracy and excluded valuable response time (RT) information. Previous approaches have therefore ignored the issue of processing efficiency, defined here in terms of optimal RT cutoff, that is, the shortest deadline at which individual people with aphasia produce their best possible naming accuracy performance. The goals of this study were therefore to (a) develop a novel model of aphasia picture naming that could accurately account for RT distributions across response types; (b) use this model to estimate the optimal RT cutoff for individual people with aphasia; and (c) explore the relationships between optimal RT cutoff, accuracy, naming ability, and aphasia severity. Method A total of 4,021 naming trials across 10 people with aphasia were scored for accuracy and RT onset. Data were fit using a novel ex-Gaussian multinomial RT model, which was then used to characterize individual optimal RT cutoffs. Results Overall, the model fitted the empirical data well and provided reliable individual estimates of optimal RT cutoff in picture naming. Optimal cutoffs ranged between approximately 5 and 10 s, which has important implications for assessment and treatment. There was no direct relationship between aphasia severity, naming RT, and optimal RT cutoff. Conclusion The multinomial ex-Gaussian modeling approach appears to be a promising and straightforward way to estimate optimal RT cutoffs in picture naming in aphasia. Limitations and future directions are discussed.Keywords
This publication has 61 references indexed in Scilit:
- Fitting Linear Mixed-Effects Models Usinglme4Journal of Statistical Software, 2015
- Connectionist diagnosis of lexical disorders in aphasiaAphasiology, 2009
- Mixed-effects modeling with crossed random effects for subjects and itemsJournal of Memory and Language, 2008
- Model‐oriented naming therapy: Testing predictions of a connectionist modelAphasiology, 2007
- The physics of optimal decision making: A formal analysis of models of performance in two-alternative forced-choice tasks.Psychological Review, 2006
- Semantic Feature Analysis Treatment for Anomia in Two Fluent Aphasia SyndromesAmerican Journal of Speech-Language Pathology, 2004
- Predictors of picture naming speedBehavior Research Methods, Instruments & Computers, 2004
- Naming the Snodgrass and Vanderwart Pictures: Effects of Age of Acquisition, Frequency, and Name AgreementThe Quarterly Journal of Experimental Psychology Section A, 1997
- Application of Semantic Feature Analysis as a Treatment for Aphasic DysnomiaAmerican Journal of Speech-Language Pathology, 1995
- Controlling the False Discovery Rate: A Practical and Powerful Approach to Multiple TestingJournal of the Royal Statistical Society: Series B (Methodological), 1995