spDCM And PEB Analysis Code

Title: Analysis Code and Behavioral Data for: Spectral Dynamic Causal Modeling of Effective Connectivity across Multiple Brain Networks in Pilot Trainees

Description:

This repository contains the MATLAB analysis scripts and behavioral datasets associated with the manuscript titled " Spectral Dynamic Causal Modeling of Effective Connectivity across Multiple Brain Networks in Pilot Trainees". The provided code implements the spectral Dynamic Causal Modeling (spDCM) and Parametric Empirical Bayes (PEB) analytical framework used to investigate effective connectivity differences between flight cadets and controls.

Repository Contents:

1. Analysis Scripts (MATLAB)

The analysis pipeline is divided into three steps, corresponding to the methods described in the manuscript:

• step1_batch_specify_DCM_region.m:
• Purpose: Script for batch processing subject data. It includes General Linear Model (GLM) specification, noise regression (White Matter and CSF), extraction of time series (Principal Eigenvariates) from 21 Regions of Interest (ROIs), and specification/estimation of the spectral DCM (spDCM) model.
• Note: This script requires preprocessed NIfTI files as input.
• step2_PEB_region_age.m:
• Purpose: Performs group-level inference using the Parametric Empirical Bayes (PEB) framework. It models group differences (Flight Group vs. Controls) with Age as a covariate, followed by Bayesian Model Reduction (BMR) and Bayesian Model Averaging (BMA).
• step3_PEB_group_Behavior_brain_together_corr.m:
• Purpose: Conducts the interaction analysis to explore group-specific associations between effective connectivity and behavioral performance (BCST accuracy).

2. Behavioral and Demographic Data

• SubjectsBehaviorData.mat: Contains anonymized behavioral metrics for the study cohort (N=76).
• age: Participant age.
• bcstCorr: Correct response rates from the Berg Card Sorting Test (BCST).
• SubjectsFlightTimeData.mat:
• FlightTime: Total flight training hours for the flight cadet group (N=39).

3. Configuration Files

• GCM_Flight_airTraffic.mat:
• Purpose: A GCM file structure used by the PEB scripts to index and locate subject-specific DCM files.
• ⚠️ Important Usage Note: This file contains absolute file paths generated during the original analysis. After downloading, users must update these paths to match the directory structure on their own local machine. Failure to update the paths will result in "file not found" errors when running the PEB scripts.

4. ROI Definitions

• ROI folder: Contains the mask files for the Regions of Interest (based on the AAL90 atlas) used for time-series extraction.

Relationship to Other Repositories:

• DCM DataSet: DOI: 10.5281/zenodo.18465984 

System Requirements:

• MATLAB (R2022b or later recommended)
• SPM12 (Statistical Parametric Mapping)

Data Availability Statement:

This repository primarily provides the analytical code and behavioral data to ensure the transparency of the methodological framework.

• Neuroimaging Data: The individual subject DCM files and raw/preprocessed NIfTI images are not included due to privacy restrictions.
• Replication: Researchers wishing to replicate the findings using their own datasets can utilize these scripts. The scripts assume a standard SPM/DCM directory structure.