Computational Models of Aphasia

Welcome to Computational Models of Aphasia at the University of California, Irvine's Auditory & Language Neuroscience Lab! This site draws much of its inspiration from the Aphasia Modeling Project. Here you may enter patient data to determine how well our model is able to fit your results, in comparison with a well-established model, or you may run our model directly.

Fit Data
Run Model
Charts and Graphs
References and Contacts
BUG REPORTS!

Fit Data

Please enter patient data to be fit:

Correct	Semantic	Formal	Mixed	Unrelated	Nonword

The data will be automatically renormalized so that it sums to 1.0.

N = Map points; max. 17,000

PLEASE NOTE: N is the number of simulated patients, not the number of observed naming attempts. The default value is an estimate of the value that provides an asymptotic average fit, for a group of 255 aphasic patients as a whole, and grouped by 5 subtypes of aphasia. Larger values are more likely to exploit the random effects in the model to improve individual fits.

Run Model

Please modify the parameters you wish, and select Run! To run the SP model, set Lexical-Auditory and Auditory-Motor to 0. There may be a short wait for results.

Weight Parameters	Other Parameters
Semantic-Lexical		Trials
Lexical-Motor		Steps
Lexical-Auditory		Decay
Auditory-Motor		Intrinsic Noise
		Activation Noise
		Initial Activation
		Jolt Activation
		Random Seed
	20%	Mixed Error Opportunities

Charts and Graphs

Poster - Society for the Neurobiology of Language Conference 2014; Amsterdam, NL

References

The SP Model

Aphasia Modeling Project.
Dell, G. S., Lawler, E. N., Harris, H. D., & Gordon, J. K. (2004). Models of errors of omission in aphasic naming. Cognitive Neuropsychology, 21(2-4), 125-145.
Foygel, D., & Dell, G.S. (2000). Models of impaired lexical access in speech production. Journal of Memory and Language, 43, 182-216.

The SLAM Model

Walker, G. M. & Hickok, G. (2016). Bridging computational approaches to speech production: The semantic-lexical-auditory-motor model (SLAM). Psychonomic Bulletin & Review, 23(2), 339-352.

Contacts

Please contact Dr. Greg Hickok or Grant M. Walker for questions or comments regarding the model or the theory behind it.

Please contact Grant M. Walker for technical questions about the model's implementation, or to report a problem with this web page.

Bug Reports!

Mar 29 2018
Model fitting sometimes returned SLAM weight values where LM>LA, which violates a constraint of the model. Data fit by SLAM prior to this bug fix should be refit.

Aug 02 2018
The Mar 29 2018 bug fix revealed another pre-existing bug. Fit values (RMSD) were incorrectly calculated for the SP model and incorrect parameters were sometimes returned. Data fit by SP prior to Aug 02 2018 should be refit.

Webmaster: Grant M. Walker <grantw@uci.edu>

Last modified: Thu Aug 02 2018