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Minicourse EDDA-DZ02

Introductory to CortiPrism fNIRS signal processing software: from artifact correction to group-level analysis


with Dariusz Zapała, Paweł Augustynowicz, Robert Kwaśniak

About this course

The fNIRS signal can be contaminated by physiological, motion, environmental, and instrumental artifacts from different sources. It is important to carefully control and minimize these various sources of artifacts to obtain reliable results. This can involve implementing appropriate data preprocessing techniques, such as signal filtering, artifact rejection, and motion correction. During the workshop, participants will be able to learn and use the new fNIRS signal processing software – CortiPrism, to apply various methods, like motion correction with Temporal Derivative Distribution Repair (TDDR), ‘bad channel’ removal based on Scalp Coupling Index (SCI) values, or adding physiological and motion signals to the GLM equation. All processing steps in CortiPrism will be run from a graphical user interface, so no coding experience is needed. Special attention will be paid to hands-on work with data.

Learning Outcomes

  • To plan steps of fNIRS signal preprocessing, including how to minimize the impact of artifacts on the signal and monitor the recording quality.
  • How to adapt the algorithms’ parameters to custom experimental procedures.
  • How to use information from motion sensors (accelerometer and gyroscope) to control movement artifacts in the signal.
  • How to adjust hemodynamic response model parameters to the features of the experimental procedure.
  • Different methods for reporting and visualizing individual and group results.

Course Plan

Level: Introductory

Pre-Requisites: None

Course Duration: 2 hours

Delivery Plan

1. Introduction and overview of course objectives (5 min).
2. How do the experimental procedure and measurement conditions affect the fNIRS signal characteristics? (15 min)
3. How to recognize the types of signal artifacts and minimize their influence? (20 min)
4. CortPrism software overview (5 min).
5. Hands-on session (60 min): software installation, preprocessing pipeline, artifact recognition and removal, general linear model in the prediction of hemodynamic response, data export and visualization of results
6. Discussion with the participants (20 min).

Why enrol on this course?

Functional near-infrared spectroscopy (fNIRS) has gained increasing popularity over the past few decades. Due to its accessibility and flexibility in the application, fNIRS became the first brain recording technique for many investigators who traditionally use behavioral and self-descriptive methods. Therefore, the software developers’ community is responsible for facilitating access to fNIRS data processing methods for researchers with less programming experience and biological signals analysis expertise. CortiPrism is an attempt to create easy-to-use software with a GUI, allowing users to go through the entire data analysis pipeline without coding skills. Our main goal is to guide users through the most popular fNIRS signal preprocessing methods and explain their impact on the study results. During the workshop, special attention will be given to artifact removal and signal correction methods.