DIAGNOSTICS, cilt.15, sa.11, ss.1-22, 2025 (SCI-Expanded)
Abstract: Background: Post-traumatic stress disorder (PTSD) is a serious psychiatric
condition that can lead to severe anxiety, depression, and cardiovascular complications
if left untreated. Early and accurate diagnosis is critical. This study aims to develop
and evaluate an artificial intelligence-based classification system using electrocardiogram
(ECG) signals for the detection of PTSD. Methods: Raw ECG signals were transformed
into time–frequency images using Continuous Wavelet Transform (CWT) to generate
2D scalogram representations. These images were classified using deep learning-based
convolutional neural networks (CNNs), including AlexNet, GoogLeNet, and ResNet50.
In parallel, statistical features were extracted directly from the ECG signals and used in
traditional machine learning (ML) classifiers for performance comparison. Four different
segment lengths (5 s, 10 s, 15 s, and 20 s) were tested to assess their effect on classification
accuracy. Results: Among the tested models, ResNet50 achieved the highest classification
accuracy of 94.92%, along with strong MCC, sensitivity, specificity, and precision metrics.
The best performance was observed with 5-s signal segments. Deep learning (DL) models
consistently outperformed traditional ML approaches. The area under the curve (AUC)
for ResNet50 reached 0.99, indicating excellent classification capability. Conclusions: This
study demonstrates that CNN-based models utilizing time–frequency representations of
ECG signals can effectively classify PTSD with high accuracy. Segment length significantly
influences model performance, with shorter segments providing more reliable results.
The proposed method shows promise for non-invasive, ECG-based diagnostic support in
PTSD detection.