### Citation
Schubert, A. L., Nunez, M. D., Hagemann, D., & Vandekerckhove, J. (2018). [Individual differences in cortical processing speed predict cognitive abilities: A model-based cognitive neuroscience account.](https://osf.io/yfa8s) Computational Brain & Behavior. doi: 10.1007/s42113-018-0021-5
# ERPIQRT
#### (Repository version 0.4.3)
Individual differences in cortical processing speed predict cognitive abilities: A model-based cognitive neuroscience account (ERPIQRT).
**Authors: Anna-Lena Schubert and Dirk Hagemann from Heidelberg University, Germany and Michael D. Nunez and Joachim Vandekerckhove from the University of California, Irvine, USA**
### Research Questions
A greater speed of information-processing may facilitate evidence acquisition during decision making and memory updating and give rise to advantages in general cognitive abilities. In this study we explore this hypothesis by using a hierarchical Bayesian cognitive modeling approach to investigate if individual differences in the velocity of evidence accumulation (a drift-diffusion model parameter that explains some variance in reaction times; RT) mediates the relationship between neural processing (estimated by event-related potentials; ERPs) and general cognitive abilities (measured by intelligence tests; IQ)
### Hypothesis
Individual differences in cognitive abilities, a latent variable related to IQ scores, are explained by individual differences in ERP latencies. This relationship is at least partially reflected in individual differences in evidence accumulation (estimated by drift-diffusion model parameter fits).
### Prerequisites
[MATLAB](https://www.mathworks.com/)
[MCMC Sampling Program: JAGS](http://mcmc-jags.sourceforge.net/)
[Program: JAGS Wiener module](https://sourceforge.net/projects/jags-wiener/)
[Scientific Python libraries](https://www.continuum.io/downloads)
[Python Repository: pyjags](https://github.com/tmiasko/pyjags)
### Downloading
The repository can be cloned with `git clone https://github.com/mdnunez/ERPIQRT.git`
The repository can also be may download via the _Download zip_ button above.
### Installation
After downloading/unzipping the repository, users will need to add these functions to the MATLAB path. In MATLAB, add the repository to the PATH with
```matlab
%Set 'artloc' to full directory path
emloc = 'C:\Users\MATLAB\ERPIQRT';
addpath(genpath(emloc));
```
### License
ERPIQRT is licensed under the GNU General Public License v3.0 and written by Anna-Lena Schubert, Michael D. Nunez, Dirk Hagemann, and Joachim Vandekerckhove.
### Further Reading
Schubert, A. L., Hagemann, D., Voss, A., Schankin, A., & Bergmann, K. (2015). [Decomposing the relationship between mental speed and mental abilities.](http://www.psychologie.uni-heidelberg.de/ae/meth/team/voss/paper/schubert_et_al_2015.pdf) Intelligence, 51, 28-46.
Schubert, A. L., Hagemann, D., & Frischkorn, G. T. (2017). [Is general intelligence little more than the speed of higher-order processing?.](http://psycnet.apa.org/record/2017-30267-001) Journal of Experimental Psychology: General, 146(10), 1498.
