General Introduction to Deep-Learning Techniques in fMRI Analysis
Hyunseok Seo1
1Korea Institute of Science and Technology, Korea, Republic of

Synopsis

Keywords: Neuro: Brain function

This general introduction provides an overview of deep-learning techniques used in fMRI analysis, focusing on clustering, dimensionality reduction, and dynamic pattern analysis. Clustering identifies functionally related regions of the brain by grouping similar data points together. Dimensionality reduction reduces the number of dimensions in the data while retaining important information to facilitate understanding of complex activity patterns. Dynamic pattern analysis examines how activity patterns change over time, identifying brain regions involved in different cognitive processes. These techniques provide valuable insights into the functional activity of the brain and have the potential to enhance our understanding of cognitive and neural processes.

General Introduction to Deep-Learning Techniques in fMRI Analysis

Functional magnetic resonance imaging (fMRI) is a neuroimaging technique used to measure brain activity by detecting changes in blood flow. Analyzing fMRI data can be challenging due to its high dimensionality and the complex spatiotemporal patterns of brain activity. Deep learning techniques have emerged as a powerful tool to address these challenges and have been applied to various aspects of fMRI analysis, including clustering, dimensionality reduction, and dynamic pattern analysis. In this talk, the general introductions of deep learning models to mitigate current challenging in fMRI analysis will be dealt with.
Clustering is a fundamental technique in unsupervised learning that groups similar data points together to identify patterns in the data. Deep learning-based clustering methods, such as deep embedded clustering (DEC) , have been applied to fMRI data analysis. DEC utilizes autoencoder architectures to learn low-dimensional feature representations and optimize clustering objectives simultaneously. These methods have shown improved accuracy and robustness compared to traditional clustering algorithms.
Dimensionality reduction is another essential technique in fMRI analysis, which involves reducing the high-dimensional fMRI data to a lower dimensional space while preserving the most relevant information. Principal component analysis (PCA) and independent component analysis (ICA) are two commonly used dimensionality reduction methods in fMRI analysis. However, deep learning-based approaches, such as variational autoencoders (VAEs), have shown improved performance by learning nonlinear mappings between high-dimensional fMRI data and low-dimensional latent representations. Additionally, adversarial autoencoders (AAEs) can further improve the quality of the learned latent space by introducing an adversarial training procedure that encourages the learned representations to follow a specific prior distribution.
Dynamic pattern analysis is a critical area of fMRI analysis that involves examining the spatiotemporal patterns of brain activity across different tasks or conditions. Dynamic functional connectivity (dFC) analysis is a popular approach to studying brain dynamics, which involves estimating the time-varying connectivity between different brain regions. Deep learning-based approaches have been developed to capture the complex temporal dynamics of fMRI data and identify dynamic functional brain networks.
In conclusion, deep learning techniques have shown great potential in addressing various challenges in fMRI data analysis, including clustering, dimensionality reduction, and dynamic pattern analysis. These methods enable the identification of functional brain networks, the reduction of high-dimensional fMRI data to low-dimensional latent representations, and the modeling of dynamic brain activity patterns. However, it is essential to carefully select appropriate architectures and hyperparameters, avoid overfitting, and validate results to ensure the accuracy and robustness of the analysis. With the continued development of deep learning techniques, we can expect to see further improvements in fMRI data analysis and our understanding of the brain's functional organization.

Acknowledgements

No acknowledgement found.

References

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Proc. Intl. Soc. Mag. Reson. Med. 31 (2023)