An extended version of the neuro-computational model GODIVA. Includes a basal ganglia (BG) - ventral premotor cortex (vPMC) loop that serves to select and initiate the correct syllables and in a timely manner.
The code was used for the simulations of developmental stuttering resulting from elevated dopamine levels and impaired corticostriatal projects (Civier et al., 2013).
The code implements the formulas given in the supplementary material of Civier et al. (2013). Each component has a function that implements it, prefixed by "update_". The model is based on the original GODIVA model (Bohland et al., 2010).
Code is also posted on the Guenther lab's website (Boston University): http://sites.bu.edu/guentherlab/software/godiva-source-code/ (2011 version)
Usage:
sim = godiva(length,condition)
<length> - the length of the simulation in GODIVA time units
<condition> - what condition to simulate:
'normal' - healthy individual
'DA' - elevated dopamine levels
'WMF' - what matter fibers impairment
Output:
plot of the results
sim - the simulation results
sim.output (neural activation over time)
sim.model (the paramaters of the model)
sim.time (time steps used)
Next step:
run plot_all to show output of simulation
run plot_colors to show important info on simulation
run BOLD/plot_response to plot hemodynamic response
Config files:
1) Global_parameters.m includes the parameters used for each condition, as well as the utterance to be produced.
2) ./defaults subdirectory includes a .mat for every component in the model. The file specifies the A and B parameters for all shunting equations used. The defaults can be overriden by including a .mat file with the same name in the ./custom subdirectory (but without the 'default_' prefix).
Author: Oren Civier
Version: 2.01
Date: 26/12/2011
REFERENCES:
Bohland, J. W., Bullock, D., and Guenther, F. H. (2010) Neural representations and mechanisms for the performance of simple speech sequences. Journal of Cognitive Neuroscience , 22(7), pp. 1504–1529.
Civier, O., Bullock, D., Max, L., and Guenther, F. H. (2013) Computational modeling of stuttering caused by impairments in a basal ganglia thalamo-cortical circuit involved in syllable selection and initiation. Brain and Language, 126(3), 263–278