fNIRS Data from the Prospective of Network Theory
Xhilda Dhamo, Eglantina Kalluçi, Eva Noka
Abstract
We analyze visibility networks constructed from signals captured from functional Near- Infrared Spectroscopy Data Acquisition and Pre-processing technology (fNIRS) making use of properties of network theory with the aim to characterize the network properties of fNIRS visibility networks. The fNIRS technology is used to capture the brain activity of dyads of two persons by measuring the oxyhemoglobin (HbO) level during a task called “MapTask”. Our approach consists in three consecutive steps: (i) firstly, we employe a sliding window technique to segment fNIRS signals; (ii) secondly, we convert the HbO signals in each sliding window to visibility networks; (iii) thirdly, we employ network properties such as diameter, clustering coefficient, assortativity, transitivity and density across different cerebral time windows. Furthermore, we investigate the degree distribution of the nodes in the networks and it is observed that they follow a power- law distribution as the length of the signal increased suggesting scale- free characteristics.
Keywords
References
Arenas, A., DĂaz-Guilera, A., Kurths, J., Moreno, Y., Zhou, C.: Synchronization in complex
networks.
Physics
Reports.
469,
93-153
(2008).
https://doi.org/https://doi.org/10.1016/j.physrep.2008.09.002
Barrat, A., Barthélemy, M., Vespignani, A.: Dynamical Processes on Complex Networks.
Cambridge University Press (2008).
Boccaletti, S., Latora, V., Moreno, Y., Chavez, M., Hwang, D.-U.: Complex networks:
Structure
and
dynamics.
Physics
Reports.
424,
175-308
(2006).
https://doi.org/https://doi.org/10.1016/j.physrep.2005.10.009Ahmed J. and Ahamed S.
(2014), “Seismic Vulnerability of RC Buildings by Considering Plan Irregularities
Using Pushover Analysis”, Global journal for research analysis, 3, 2014, 42-47.
Chen, G., Wang, X., Li, X.: Fundamentals of Complex Networks: Models, Structures and
Dynamics. Willey (2015)
Dhamo X, Kalluçi E, Dray G, et al (2024a) Global Synchronization Measure Applied to Brain
Signals Data. In: Studies in Computational Intelligence. Springer, France
Dhamo X, Kalluçi E, Noka E, et al (2024b) Synchronization processes in fNIRS visibility
networks. Applied Network Science 9:. https://doi.org/https://doi.org/10.1007/s41109-
024-00663-x
Estrada, E., Knight, P.A.: A First Course in Network Theory. Oxford University Press (2025)
Halvin, S., Kenett, D.Y., Ben-Jacob, E., Bunde, A., Cohen, R., Hermann, H., Kantelhardt, J.W.,
Kertész, J., Kirkpatrick, S., Kurths, J., Portugali, J., Solomon, S.: Challenges in network
science: Applications to infrastructures, climate, social systems and economics. The
European
Physical
Journal
Special
Topics.
273-293
(2012).
https://doi.org/https://doi.org/10.1140/epjst/e2012-01695-x
Lacasa, L., Luque, B., Ballesteros, F., Luque, J., Nuño, J.C.: From time series to complex
networks: The visibility graph. Applied Mathematics. 105, 4972-4975 (2008).
https://doi.org/https://doi.org/10.1073/pnas.0709247105
Lacasa, L., Luque, B., Luque, J., Nuño, J.C.: The visibility graph: A new method for estimating
the Hurst exponent of fractional Brownian motion. Europhysics Letters. 86, (2009).
https://doi.org/10.1209/0295-5075/86/30001
Lacasa, L., Nicosia, V., Latora, V.: Network structure of multivariate time series. Scientific
Reports. 5, (2015). https://doi.org/https://doi. org/10.1038/srep15508
Lacasa, L., Nuñez, A., Roldán, É., Parrondo, J.M.R., Luque, B.: Time series irreversibility: a
visibility graph approach. The European Physical Journal B. 85, (2012).
https://doi.org/https://doi.org/10.1140/epjb/e2012-20809-8
Li, R., Mayseless, N., Balters, S., Reiss, A.L.: Dynamic inter-brain synchrony in real-life inter-
personal cooperation: A functional near-infrared spectroscopy hyperscanning study.
NeuroImage.
238,
(2021).
https://doi.org/https://doi.org/10.1016/j.neuroimage.2021.118263
Luque B, Lacasa L, Ballesteros F, Luque J (2009) Horizontal visibility graphs: Exact results
for
random
time
series.
Physical
Review
E
80:.
https://doi.org/https://doi.org/10.1103/PhysRevE.80.046103
Mira- Iglesias, A., Conejero, J.A., Navarro-Pardo, E.: Natural visibility graphs for diagnosing
attention deficit hyperactivity disorder (ADHD). Electronic Notes in Discrete
Mathematics.
54,
337-342
(2016).
https://doi.org/https://doi.org/10.1016/j.endm.2016.09.058
Newman, M.: Networks. Oxford University Press (2018)
M.E.J. Newman, Modularity and community structure in networks, Proc. Natl. Acad. Sci.
U.S.A. 103 (23) 8577-8582, https://doi.org/10.1073/pnas.0601602103 (2006).
Sannino, S., Stramaglia, S., Lacasa, L., Marinazzo, D.: Visibility graphs for fMRI data:
Multiplex temporal graphs and their modulations across resting-state networks.
Network
Neuroscience.
1,
208-221
(2017).
https://doi.org/https://doi.org/10.1162/NETN_a_00012
Wang, X., Zhang, Y., He, Y., Lu, K., Hao, N.: Dynamic Inter-Brain Networks Correspond with
Specific Communication Behaviors: Using Functional Near-Infrared Spectroscopy
Hyperscanning During Creative and Non-creative Communication. Frontiers in Human
Neuroscience. 16, (2022). https://doi.org/https://doi.org/10.3389/fnhum.2022.907332