{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,22]],"date-time":"2026-01-22T05:29:38Z","timestamp":1769059778724,"version":"3.49.0"},"reference-count":38,"publisher":"MDPI AG","issue":"9","license":[{"start":{"date-parts":[[2023,4,30]],"date-time":"2023-04-30T00:00:00Z","timestamp":1682812800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Gait and balance are an intricate interplay between the brain, nervous system, sensory organs, and musculoskeletal system. They are greatly influenced by the type of footwear, walking patterns, and surface. This exploratory study examines the effects of the Infinity Walk, pronation, and footwear conditions on brain effective connectivity patterns. A continuous-wave functional near-infrared spectroscopy device collected data from five healthy participants. A highly computationally efficient connectivity model based on the Grange causal relationship between the channels was applied to data to find the effective relationship between inter- and intra-hemispheric brain connectivity. Brain regions of interest (ROI) were less connected during the barefoot condition than during other complex walks. Conversely, the highest interconnectedness between ROI was observed while wearing flat insoles and medially wedged sandals, which is a relatively difficult type of footwear to walk in. No statistically significant (p-value &lt;0.05) effect on connectivity patterns was observed during the corrected pronated posture. The regions designated as motoric, sensorimotor, and temporal became increasingly connected with difficult walking patterns and footwear conditions. The Infinity Walk causes effective bidirectional connections between ROI across all conditions and both hemispheres. Due to its repetitive pattern, the Infinity Walk is a good test method, particularly for neuro-rehabilitation and motoric learning experiments.<\/jats:p>","DOI":"10.3390\/s23094422","type":"journal-article","created":{"date-parts":[[2023,5,1]],"date-time":"2023-05-01T12:12:11Z","timestamp":1682943131000},"page":"4422","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":3,"title":["Brain Connectivity Analysis in Distinct Footwear Conditions during Infinity Walk Using fNIRS"],"prefix":"10.3390","volume":"23","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-5563-8920","authenticated-orcid":false,"given":"Haroon","family":"Khan","sequence":"first","affiliation":[{"name":"Department of Mechanical, Electronics and Chemical Engineering, OsloMet\u2013Oslo Metropolitan University, 0167 Oslo, Norway"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6495-1305","authenticated-orcid":false,"given":"Marco Antonio","family":"Pinto-Orellana","sequence":"additional","affiliation":[{"name":"Department of Mechanical, Electronics and Chemical Engineering, OsloMet\u2013Oslo Metropolitan University, 0167 Oslo, Norway"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7664-5513","authenticated-orcid":false,"given":"Peyman","family":"Mirtaheri","sequence":"additional","affiliation":[{"name":"Department of Mechanical, Electronics and Chemical Engineering, OsloMet\u2013Oslo Metropolitan University, 0167 Oslo, Norway"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2023,4,30]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Aali, S., Rezazadeh, F., Badicu, G., and Grosz, W.R. (2021). Effect of Heel-First Strike Gait on Knee and Ankle Mechanics. Medicina, 57.","DOI":"10.3390\/medicina57070657"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"169","DOI":"10.2165\/00007256-199826030-00003","article-title":"Pronation in runners","volume":"26","author":"Hintermann","year":"1998","journal-title":"Sport. Med."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"440","DOI":"10.1136\/bjsports-2013-092202","article-title":"Foot pronation is not associated with increased injury risk in novice runners wearing a neutral shoe: A 1-year prospective cohort study","volume":"48","author":"Nielsen","year":"2014","journal-title":"Br. J. Sport. Med."},{"key":"ref_4","unstructured":"Myers, T. (2009). Anatomy Trains: Myofascial Meridians for Manual and Movement Therapists, Elsevier."},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"480","DOI":"10.1177\/1941738112448055","article-title":"Is There Evidence to Support a Forefoot Strike Pattern in Barefoot Runners? A Review","volume":"4","author":"Lorenz","year":"2012","journal-title":"Sport. Health A Multidiscip. Approach"},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"1293","DOI":"10.1093\/brain\/123.7.1293","article-title":"Cerebral specialization and interhemispheric communication: Does the corpus callosum enable the human condition?","volume":"123","author":"Gazzaniga","year":"2000","journal-title":"Brain"},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"160","DOI":"10.1038\/nrn1849","article-title":"Dynamics of hemispheric specialization and integration in the context of motor control","volume":"7","author":"Serrien","year":"2006","journal-title":"Nat. Rev. Neurosci."},{"key":"ref_8","unstructured":"Sunbeck, D. (1996). Infinity Walk: Preparing Your Mind to Learn, Jalmar Press."},{"key":"ref_9","first-page":"113","article-title":"Infinity Walk: Preparing Your Mind to Learn!","volume":"13","author":"Szymanski","year":"1997","journal-title":"Res. Teach. Dev. Educ."},{"key":"ref_10","unstructured":"Sunbeck, D.T. (2006). \u201cFigure-Eight\u201d Track, Apparatus and Method for Sensory-Motor Exercise. (7,115,071), U.S. Patent."},{"key":"ref_11","unstructured":"Sunbeck, D. (2002). The Complete Infinity Walk\u2014Book I, The Physical Self, Leonardo Foundation Press."},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"232","DOI":"10.1016\/j.mporth.2016.04.015","article-title":"Biomechanics of the ankle","volume":"30","author":"Brockett","year":"2016","journal-title":"Orthop. Trauma"},{"key":"ref_13","first-page":"A7","article-title":"O19 Cortical activation variability is altered in individuals with chronic ankle instability during single limb postural control","volume":"51","author":"Rosen","year":"2017","journal-title":"BMJ J."},{"key":"ref_14","doi-asserted-by":"crossref","unstructured":"Jafarnezhadgero, A., Alavi-Mehr, S.M., and Granacher, U. (2019). Effects of anti-pronation shoes on lower limb kinematics and kinetics in female runners with pronated feet: The role of physical fatigue. PLoS ONE, 14.","DOI":"10.1371\/journal.pone.0216818"},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"242","DOI":"10.1016\/j.gaitpost.2019.09.023","article-title":"Effects of medially wedged insoles on the biomechanics of the lower limbs of runners with excessive foot pronation and foot varus alignment","volume":"74","author":"Braga","year":"2019","journal-title":"Gait Posture"},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"605","DOI":"10.3389\/fnhum.2020.613254","article-title":"Analysis of Human Gait Using Hybrid EEG-fNIRS-Based BCI System: A Review","volume":"14","author":"Khan","year":"2021","journal-title":"Front. Hum. Neurosci."},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"1806374","DOI":"10.1155\/2018\/1806374","article-title":"Portable and wearable brain technologies for neuroenhancement and neurorehabilitation","volume":"2018","author":"Naseer","year":"2018","journal-title":"BioMed Res. Int."},{"key":"ref_18","doi-asserted-by":"crossref","unstructured":"Saikia, M.J., Besio, W.G., and Mankodiya, K. (2021). The validation of a portable functional nirs system for assessing mental workload. Sensors, 21.","DOI":"10.3390\/s21113810"},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"153","DOI":"10.1109\/TNSRE.2005.847377","article-title":"Functional near-infrared neuroimaging","volume":"13","author":"Izzetoglu","year":"2005","journal-title":"IEEE Trans. Neural Syst. Rehabil. Eng."},{"key":"ref_20","doi-asserted-by":"crossref","unstructured":"Hamid, H., Naseer, N., Nazeer, H., Khan, M.J., Khan, R.A., and Shahbaz Khan, U. (2022). Analyzing classification performance of fNIRS-BCI for gait rehabilitation using deep neural networks. Sensors, 22.","DOI":"10.3390\/s22051932"},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"718","DOI":"10.4085\/1062-6050-448-17","article-title":"Alterations in cortical activation among individuals with chronic ankle instability during single-limb postural control","volume":"54","author":"Rosen","year":"2019","journal-title":"J. Athl. Train."},{"key":"ref_22","doi-asserted-by":"crossref","unstructured":"Khan, H., Nazeer, H., Engell, H., Naseer, N., Korostynska, O., and Mirtaheri, P. (2021, January 28\u201330). Prefrontal Cortex Activation Measured during Different Footwear and Ground Conditions Using fNIRS\u2014A Case Study. Proceedings of the 2021 International Conference on Artificial Intelligence and Mechatronics Systems (AIMS), Bandung, Indonesia.","DOI":"10.1109\/AIMS52415.2021.9466026"},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"e13628","DOI":"10.1016\/j.heliyon.2023.e13628","article-title":"Single-leg stance on a challenging surface can enhance cortical activation in the right hemisphere\u2014A case study","volume":"9","author":"Khan","year":"2023","journal-title":"Heliyon"},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"1265","DOI":"10.1109\/TNSRE.2016.2551642","article-title":"Directed functional connectivity in fronto-centroparietal circuit correlates with motor adaptation in gait training","volume":"24","author":"Youssofzadeh","year":"2016","journal-title":"IEEE Trans. Neural Syst. Rehabil. Eng."},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"160","DOI":"10.1016\/j.neubiorev.2017.10.002","article-title":"fNIRS response during walking\u2014Artefact or cortical activity? A systematic review","volume":"83","author":"Vitorio","year":"2017","journal-title":"Neurosci. Biobehav. Rev."},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"540","DOI":"10.1016\/j.neuroimage.2012.09.049","article-title":"Granger causality analysis of fMRI BOLD signals is invariant to hemodynamic convolution but not downsampling","volume":"65","author":"Seth","year":"2013","journal-title":"Neuroimage"},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"e6833","DOI":"10.7717\/peerj.6833","article-title":"Prefrontal cortical activation measured by fNIRS during walking: Effects of age, disease and secondary task","volume":"7","author":"Pelicioni","year":"2019","journal-title":"PeerJ"},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"67","DOI":"10.1016\/j.archger.2015.11.005","article-title":"Differences in foot sensitivity and plantar pressure between young adults and elderly","volume":"63","author":"Machado","year":"2016","journal-title":"Arch. Gerontol. Geriatr."},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"390","DOI":"10.3389\/fnagi.2017.00390","article-title":"Gait speed and gait variability are associated with different functional brain networks","volume":"9","author":"Lo","year":"2017","journal-title":"Front. Aging Neurosci."},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"3341","DOI":"10.1038\/s41598-018-21716-z","article-title":"fNIRS optodes\u2019 location decider (fOLD): A toolbox for probe arrangement guided by brain regions-of-interest","volume":"8","author":"Morais","year":"2018","journal-title":"Sci. Rep."},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"313","DOI":"10.1016\/j.neuroimage.2010.07.033","article-title":"Unbiased average age-appropriate atlases for pediatric studies","volume":"54","author":"Fonov","year":"2011","journal-title":"NeuroImage"},{"key":"ref_32","doi-asserted-by":"crossref","unstructured":"Nicolai, E., Michelson, N., Settell, M., Hara, S., Trevathan, J., Asp, A., Stocking, K., Lujan, J., Kozai, T., and Ludwig, K. (2018). Design Choices for Next-Generation Neurotechnology Can Impact Motion Artifact in Electrophysiological and Fast-Scan Cyclic Voltammetry Measurements. Micromachines, 9.","DOI":"10.3390\/mi9100494"},{"key":"ref_33","doi-asserted-by":"crossref","unstructured":"Lutkepohl, H. (2005). New Introduction to Multiple Time Series Analysis, New York Springer.","DOI":"10.1007\/978-3-540-27752-1"},{"key":"ref_34","unstructured":"Shumway, R.H., and Stoffer, D.S. (2006). Time Series Analysis and Its Applications: With R Examples, Springer. [2nd ed.]. Springer Texts in Statistics."},{"key":"ref_35","unstructured":"Pinto-Orellana, M.A., Mirtaheri, P., Hammer, H.L., and Ombao, H. (2021). SCAU: Modeling Spectral Causality for Multivariate Time Series with Applications to Electroencephalograms. arXiv."},{"key":"ref_36","doi-asserted-by":"crossref","unstructured":"Ombao, H., and Pinto, M. (2021). Spectral Dependence. arXiv.","DOI":"10.1016\/j.ecosta.2022.10.005"},{"key":"ref_37","doi-asserted-by":"crossref","unstructured":"Sak, H., Senior, A.W., and Beaufays, F. (2014). Long Short-Term Memory Based Recurrent Neural Network Architectures for Large Vocabulary Speech Recognition. arXiv.","DOI":"10.21437\/Interspeech.2014-80"},{"key":"ref_38","doi-asserted-by":"crossref","first-page":"1075288","DOI":"10.3389\/fnins.2022.1075288","article-title":"The Temporal Voice Areas are not \u201cjust\u201d Speech Areas","volume":"16","author":"Trapeau","year":"2022","journal-title":"Front. Neurosci."}],"container-title":["Sensors"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1424-8220\/23\/9\/4422\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,10]],"date-time":"2025-10-10T19:27:15Z","timestamp":1760124435000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1424-8220\/23\/9\/4422"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2023,4,30]]},"references-count":38,"journal-issue":{"issue":"9","published-online":{"date-parts":[[2023,5]]}},"alternative-id":["s23094422"],"URL":"https:\/\/doi.org\/10.3390\/s23094422","relation":{},"ISSN":["1424-8220"],"issn-type":[{"value":"1424-8220","type":"electronic"}],"subject":[],"published":{"date-parts":[[2023,4,30]]}}}