Releases

Latest Release

v2.3.0 (Latest Release)

Release Date: March 17, 2026

A major release with new analysis capabilities, broader simulation support, diffusion pipeline integration, and a modernized codebase built on SimNIBS 4.6.0.

Preprocessing & Segmentation

  • Subcortical sub-nuclei segmentation — hippocampal and thalamic sub-nuclei are now automatically segmented as part of the FreeSurfer recon-all pipeline.
  • QSIPrep / QSIRecon integration — diffusion MRI preprocessing and reconstruction are now available through the GUI and CLI, including DTI extraction for anisotropic simulations. This still needs further validation, but works well internally.
  • MASSP2021 nuclei atlas — added under the MNI resources as a built-in subcortical atlas for targeting thalamic and brainstem nuclei. Can be selected in the group-level visualization step.

Simulation & Optimization

  • Upgraded to SimNIBS 4.6.0 — the underlying finite-element engine is now at its latest version, bringing improved meshing and solver accuracy.
  • Anisotropic conductivity in optimization — flex-search now supports all 4 SimNIBS conductivity models (isotropic, volume-normalized, direct, and mean-conductivity). Select via the GUI dropdown or the anisotropy_type config parameter. Fine-tune with aniso_maxratio and aniso_maxcond.
  • White matter / gray matter tissue targeting — flex-search lets you choose whether to optimize over gray matter, white matter, or both.
  • Focality Pareto sweep — new tool to systematically explore the trade-off between field intensity and focality across a grid of threshold combinations, producing a Pareto plot and summary table.
  • Batch simulation — run multiple simulation configurations in sequence from a single GUI session.

Analysis

  • Combined multi-ROI analysis — select multiple atlas regions and analyze them as a single combined ROI. Outputs use a +-joined naming convention (e.g., precentral+postcentral/).
  • Tissue-type selection in analysis — choose GM, WM, or both when running voxel-space analyses.

Infrastructure & Usability

  • Singularity / Apptainer support — run TI-Toolbox on HPC clusters without Docker.
  • HTML report generation — automated reports for simulation and preprocessing results.
  • Redesigned GUI — modernized styling, consistent console output, and reusable ROI/electrode/solver widgets across all tabs.
  • Simplified Python scripting API — cleaner imports and flat configuration dataclasses make scripting simulations, optimizations, and analyses more straightforward. See the updated API documentation for examples.
  • Improved CI/CD and test suite — comprehensive automated testing with coverage tracking.

Breaking Changes (for scripters)

  • The Python API has been significantly simplified. If you have scripts that import from tit, please refer to the updated API documentation for the new import paths and configuration classes. Key changes:

Full release notes · API documentation

Desktop App (latest): macOS Intel · macOS Apple Silicon · Windows · Linux AppImage · Linux deb

Other:

For installation instructions, see the Installation Guide.

Getting Help

If you encounter issues with any release:

  1. Check the Installation Guide for setup instructions
  2. Review the Troubleshooting section
  3. Search existing issues
  4. Ask in GitHub Discussions