## README

MATLAB2016b was used to run these scripts. 

ROASTv2.7 (https://www.parralab.org/roast/) was used to run current flow models. Scripts should also work on later versions of ROAST. 

spm12 (https://www.fil.ion.ucl.ac.uk/spm/software/spm12/) was used for data pre-processing and analysis of E-field data extracted from current flow models produced by ROAST.

>The specified protocol defined in these scripts are those used in the following article: "Evans, C., Bachmann, C., Lee, J. S., Gregoriou, E., Ward, N., & Bestmann, S. (2020). Dose-controlled tDCS reduces electric field intensity variability at a cortical target site. Brain stimulation, 13(1), 125-136."


## SCRIPTS 

> In order to replicate data from Evans et al. (2020), the following scripts must be run in the order specified by roman numerals:


- 'i_ROAST_fixedDose.m'

Runs ROAST CFM applying a FIXED DOSE of tDCS to all MR scans.

- 'ii_Normalise.m'

Converts structural MRI and E-field magnitude (emag) images generated by ROAST from native to standard space

- 'iii_Smooth.m' 

Smooths normalised E-field magnitude (emag) images generated by ROAST using 4mm smoothing kernel

- 'iv_AveMRI_GMWMMask.m'

Creates i) an average structural MR image of all individuals: 'AllPTs_Structural.nii', ii) a binary grey and white matter mask based on the average structural image: 'GMWMBinaryMask.nii'

- 'v_Ttest_ROI.m'

Runs one-sample t-test on smoothed/normalised E-field images, ii) extracts the eigenvariates from target ROI, additional ROIS, and ROI where global maximum is located (i.e. statistical maximum with least variance in E-field) 

- 'vi_ROAST_individualisedDose.m'

Runs ROAST CFM applying an INDIVIDUALISED DOSE of tDCS to all MR scans based on the average E-field intensity across the sample observed in cortical target

> Additional useful scripts

- 'AveMRI.m' 

Creates an average structural MR image of all individuals

- 'Plot_Efield_targetROI'

Creates a figure showing the distribution of E-field intensity across the sample in the target ROI when applying 2x Fixed-Dose and 2x Individualised-Dose

3. 'Plot_StimOutput_IndivDose'

Creates a figure showing distribution of Stimulator Output across the sample when dose-controlling to fix E-field intensity at cortical target ROI.