Publications

1. N. Xu, X. Zhang, W-J Pan, J.L. Smith, J.W. Allen, S.D. Keilholz. “Modeling and validation of temporally dynamic causal interactions in functional brain networks."

2. N. Xu, L. Zhang, W-J Pan, Z. Li, K-H Chuang, S.D. Keilholz. “Uniformity of spatiotemporal dynamics across rodents and humans.”

1. [CABN 2024] D. Seeburger, N. Xu, M. Ma, S. Larson, C. Godwin,  S.D. Keilholz,  E.H. Schumacher. "Time-varying functional connectivity predicts fluctuations in sustained attention in a serial tapping task." Cognitive, Affective, and Behavioral Neuroscience 24: 111–125 (2024). doi: 10.3758/s13415-024-01156-1.

2. [Submitted] N. Xu*, B. Yousefi, N. Anumba, T. J. LaGrow, X. Zhang, S.D. Keilholz. "QPPLab: A generally applicable software package for detecting, analyzing, and visualizing large-scale quasiperiodic spatiotemporal patterns (QPPs) of brain activity." invited submission to SoftwareX. (bioRxiv).

3. [Imaging Neurosci. 2023] N. Xu*, D.M. Smith, G. Jeno, D. Seeburger, E. Schumacher, S.D. Keilholz. “The interaction between random and systematic visual stimulation and infraslow quasiperiodic spatiotemporal patterns of whole brain activity.” Imaging Neuroscience 1:1–19 (2023). doi: 10.1162/imag_a_00002 (bioRxiv).

4. [Aperture Neuro 2023] N. Xu*, L. Zhang+, S. Larson+, Z Li, N. Anumba, L. Daley, W-J Pan, K-H Chuang,  S.D. Keilholz. "Rodent whole-brain fMRI data preprocessing toolbox." Aperture Neuro 3:1-3 (2023). doi:10.52294/001c.85075 (GitHub).

5. [MRM 2023] N. Anumba , E. Maltbie , W-J Pan, T.J LaGrow , N. Xu, S.D. Keilholz. "Spatial and spectral components of the BOLD global signal in rat rs-fMRI." Magnetic Resonance in Medicine (2023). doi: 10.1002/mrm.29824 (bioRxiv).

6. [Front Neurosci 2022] N. Xu*, T.J. LaGrow, N. Anumba, A. Lee, X. Zhang, B. Yousefi, Y. Bassil, G.P. Clavijo, V. Khalilzad Sharghi, E. Maltbie, L. Meyer-Baese, M. Nezafati, W-J Pan*, S.D. Keilholz*. "Functional connectivity of the brain across rodents and humans." Frontiers in Neuroscience 16:816331 (2022) doi: 10.3389/fnins.2022.816331 (arXiv).

7. [SISC 2021] N. Xu*, P.C. Doerschuk, "Computation of real-valued basis functions which transform as irreducible representations of the polyhedral groups". SIAM Journal on Scientific Computing 43:6 (2021), doi: 10.1137/20M1318183. [Software]

8. [Neuroimage 2021] N. Xu*, P.C. Doerschuk, S.D. Keilholz+, R.N. Spreng+ "Spatiotemporal functional interactivity among large-scale brain networks". NeuroImage 227:117628 (2021), doi: 10.1016/j.neuroimage.2020.117628 (bioRxiv). 

9. [Front Neurosci 2020] S. Keilholz, E. Maltbie, X. Zhang, B. Yousefi, W. Pan, N. Xu, M. Nezafati, T. J. LaGrow, and Y. Guo. "Relationship between basic properties of BOLD fluctuations and calculated metrics of complexity in the Human Connectome Project." Frontiers in Neuroscience 14:939 (2020), doi: 10.3389/fnins.2020.550923.

10. [Laban 2019] N. Xu+, D. Patel+, H. Lu, "Digging deeper: methodologies for high-content phenotyping in Caenorhabditis elegans." Lab Animal 48:7 (2019) (arXiv).

11. [IEEE TIP 2019] N. Xu, P.C. Doerschuk, "Reconstruction of stochastic 3-D signals with symmetric statistics from 2-D projection images motivated by cryo-electron microscopy". IEEE Transactions on Image Processing, 28:11 (2019), doi: 10.1109/TIP.2019.2915631 (arXiv). 

12. [JSB 2018] N. Xu,  D. Veesler, P.C. Doerschuk and J. E. Johnson, "Allosteric effects in bacteriophage HK97 procapsids revealed directly from covariance analysis of cryo-EM data". Journal of Structural Biology 202:2 (2018), doi: 10.3389/fnins.2017.00271.

13. [Front Neurosci 2017] N. Xu*, R.N. Spreng, P.C. Doerschuk, "Initial validation for the estimation of resting-state fMRI effective connectivity: A generalized correlation approach". Frontiers in Neuroscience 11:271 (2017), doi: 10.3389/fnins.2017.00271. [Software] 

14. [Curr Opin Virol 2016] P.C. Doerschuk, Y. Gong, N. Xu, T. Domitrovic, J.E. Johnson, "Virus Particle Dynamics Derived from CryoEM Studies", Current Opinion in Virology, 18, 57-63, doi: 10.1016/j.coviro.2016.02.011.

Conference Manuscripts 

1. [EMBC 2016b] N. Xu, P.C. Doerschuk. "Statistical characterization of ensembles of symmetric virus particles: 3-D stochastic signal reconstruction from electron microscope images." The 38th Annual International Conference of the IEEE Engineering in Medicine and Biology Society, 2016. doi: 10.1109/EMBC.2016.7591598. (EMBS Student Paper Competition Finalist, Top 0.4% conference proceedings)

2. [ICIP 2015] N. Xu, P.C. Doerschuk. "Reconstruction for stochastic 3-D signals with symmetric statistics in noise: electron microscopy of virus particles." The 22nd IEEE International Conference on Image Processing, 2015. doi: 10.1109/ICIP.2015.7351039. (1 of Top 127 papers recognized as "Top 10%"; 1 of Top 34 papers demonstrated in the "Show & Tell" session)

3. [SPIE 2015] N. Xu, Y. Gong, Q. Wang, Y. Zheng, P.C. Doerschuk. "Characterizing heterogeneity among virus particles by stochastic 3D signal reconstruction." SPIE Optics + Photonics 2015. doi: 10.1117/12.2193791SPIE 2015.

4. [ICIP 2014] N. Xu, R.N. Spreng, P.C. Doerschuk. "Directed interactivity of large-scale brain networks: Introducing a new method for estimating resting-state effective connectivity MRI." The 21st IEEE International Conference on Image Processing, 2014. doi: 10.1109/ICIP.2014.7025712 .

5. [SRS 2014] N. Xu, Y. Gong, Yili Zheng, Qiu Wang, Peter C. Doerschuk. "3-D statistical characterization of the heterogeneity of biological macromolecular complexes by electron microscopy." Optical Society of America, Signal Recovery and Synthesis, 2014.doi: 10.1364/SRS.2014.STu3F.4.

Conference Abstract Papers

6. [OHBM 2024a] N. Xu, X. Zhang, W-J Pan, J.L. Smith, J.W. Allen, V.D. Calhoun, S.D. Keilholz. “Time-varying causal interactions in the functional brain networks: Modeling and Validation.” The Organization for Human Brain Mapping Annual Meeting 2024.

7. [OHBM 2024b] N. Anumba, M. Kelberman, N. Xu, W-J Pan, D. Weinshenker, S.D. Keilholz. “The effects of locus coeruleus stimulation on quasi-periodic patterns in rats.” The Organization for Human Brain Mapping Annual Meeting 2024.

8. [ASFNR 2023] A. Trofimova, J. Smith, N. Xu, S. Keilholz, R. Gore, J.W. Allen. Hyperconnected” Vestibular State in Subacute and Chronic Post-Concussive Vestibular Dysfunction Using Dynamic Whole Brain Functional Connectivity Analysis. The 16th Annual Meeting of the American Society of Functional Neuroradiology (2023). (Oral presentation)

9. [OHBM 2023a] N. Xu, D.M. Smith, G. Jeno, D.T. Seeburger, E.H. Schumacher, S.D. Keilholz. "The interaction between visual stimulation and intrinsic infraslow whole brain activity in humans." The Organization for Human Brain Mapping Annual Meeting 2023.

10. [OHBM 2023b] T. Bolt, N. Xu, L. Daley, T.J. LaGrow, W-J Pan, E. Schumacher, S. Keilholz. "Distribution of large-scale spatiotemporal patterns within and across individuals." The Organization for Human Brain Mapping Annual Meeting 2023.

11. [AAIC 2022] N. Anumba, M. Kelberman, C. Smith, W-J Pan, P. Clavijo, N. Xu, A. Marriott, E. Kim, D. Weinshenker, S. Keilholz. "The effects of locus coeruleus stimulation on the BOLD global signal in TgF344-AD rats." Alzheimer's Association International Conference 2022.

12. [OHBM 2022] N. Xu , J. Smith , J. Allen , S.D. Keilholz. "Dynamic spatiotemporal interactions in vestibular networks affected by concussive syndromes." The Organization for Human Brain Mapping Annual Meeting 2022.

13. [CNS 2022a] D. Seeburger, N. Xu, C. Godwin, M. Ma, S.D. Keilholz, E.H. Schumacher. "Identifying the Neural Mechanisms of Zone State Performance using Time-varying Functional Connectivity Methods." Cognitive Neuroscience Society 2022 Annual Meeting. (Oral presentation)

14. [CNS 2022b] Y-J Lee, D. Seeburger, S. Dhawan, T. Nguyen, N. Xu, M. Ma, A. Abbas, W. Majeed, G. Thompson, S.D. Keilholz, E.H. Schumacher. "Investigating the relationship between sustained attention and quasi-periodic brain activity patterns with the psychomotor vigilance task." Cognitive Neuroscience Society 2022 Annual Meeting.

15. [OHBM 2021] N. Xu, D.M. Smith, G. Jeno, D.T. Seeburger, E.H. Schumacher, S.D. Keilholz. “Quasiperiodic patterns and BOLD response entrained by visual stimulation in the human brain.” The Organization for Human Brain Mapping Anual Meeting 2021.

16. [OHBM 2020a] N. Xu, R.N. Spreng, S.D. Keilholz, "Investigation of spatiotemporal functional interactivity among large-scale brain networks." The Organization for Human Brain Mapping Annual Meeting, 2020. (Oral presentation, Top 4% accepted abstract papers)

17. [OHBM 2020b] W-J Pan, V. Khalilzad-Sharghi, E. Maltbie, X. Zhang, N. Xu, S.D. Keilholz. “Frequency-domain Correlation within Cerebral Functional Systems in Rats Authors: Introduction” The Organization for Human Brain Mapping Anual Meeting 2020.

18. [EMBC 2016a] N. Xu, P.C. Doerschuk, R.N. Spreng, "What are the most talkative brain regions?" The 38th Annual International Conference of the IEEE Engineering in Medicine and Biology Society, 2016. (Late-breaking research paper)

19. [CNS 2014] N. Xu, R.N. Spreng, P.C. Doerschuk, "Directed interactivity of large-scale brain networks: Introducing a new method for estimating resting-state effective connectivity MRI." Cognitive Neuroscience Society 2014 Annual Meeting.