Applying fMRI complexity analyses to the single subject: a case study for proposed neurodiagnostics

ABSTRACT

Nonlinear dynamic tools have been statistically validated at the group level to identify subtle differences in system wide regulation of brain meso-circuits, often increasing clinical sensitivity over conventional analyses alone. We explored the feasibility of extracting information at the single-subject level, illustrating two pairs of healthy individuals with psychological differences in stress reactivity. We applied statistical and nonlinear dynamic tools to capture key characteristics of the prefrontal-limbic loop. We compared single subject results with statistical results for the larger group. We concluded that complexity analyses may identify important differences at the single-subject level, supporting their potential towards neurodiagnostic applications.

KEYWORDS:

• Stress reactivity
• fMRI
• single-subject analysis
• principal components
• power spectrum scale invariance

Acknowledgments

We would like to thank Dr. Lilianne Mujica-Parodi and the Laboratory for Computational Neurodiagnostics for providing the subject data, and Ms. Sanja Nedic for the helpful discussions.

Disclosure statement

No potential conflict of interest was reported by the authors.