## 4 Discussion
### Future Directions  
This system can be used immediately to measure both degenerative impairments in spatial navigation and the potential improvement of any intervention or therapy designed to address spatial navigation. However, a necessary first step is to test as many different participants subgroups in this system as possible, for example, children/teens, adults, and elderly people. In the same line, both healthy and stressed subjects, as well as the effects of lifestyle will for sure provide very interesting information about human spatial navigation.  
Nevertheless, joint evaluation of neural activity correlated with performance of spatial navigation is a promising subfield to generate relevant information about the dynamics of navigation. Furthermore, this information can be easily contrasted with individual molecular profiles of selected, hypothesis-driven lists of potential mediators of different interventions (as for example epigenetic effectors). All this information might be used, in turn, to design personalized therapies or lifestyle interventions that would be tested with this system.  
The following supporting information can be downloaded at: [[https://www.mdpi.com/article/10.3390/app12199707/s1](https://www.mdpi.com/article/10.3390/app12199707/s1)]([https://www.mdpi.com/article/10.3390/app12199707/s1](https://www.mdpi.com/article/10.3390/app12199707/s1)), Figure S1: Other complex interactions between variables.  
Conceptualization, P.M., E.C., P.T., A.O., L.L.-M. and J.L.T.; Formal analysis, P.M., E.C., P.T., R.G.B. and J.L.T.; Investigation, P.M.; Methodology, P.M., E.C., P.T., B.F.-G., C.T.-Z., E.L.-G., A.E.D.M., R.G.B., V.C.-P., R.D.I.V., V.S.-L., A.O., L.L.-M. and J.L.T.; Resources, P.M., B.F.-G., C.T.-Z., E.L.-G., A.E.D.M., V.C.-P., R.D.I.V., V.S.-L., A.O., L.L.-M. and J.L.T.; Software, P.M.; Supervision, J.L.T.; Validation, P.M. and J.L.T.; Visualization, P.M., E.C. and P.T.; Writing--original draft, J.L.T.; Writing--review & editing, P.M. and J.L.T. All authors will be informed about each step of manuscript processing including submission, revision reminder, etc. via emails from our system or assigned Assistant Editor. All authors have read and agreed to the published version of the manuscript.  
P.M. was funded by a predoctoral fellowship (FPI) grant, PRE2020/093032, from the Ministerio de Ciencia e Innovacion; E.C. was funded by a predoctoral fellowship (FPI) grant, BES-2017/080415, from the Ministerio de Economia y Competitividad; P.T. was funded by a predoctoral fellowship (FPU) grant, 18/00069, from the Ministerio de Universidades. This research received no other external specific funding.  
The study was conducted according to the guidelines of the Declaration of Helsinki, and approved by the CSIC Ethics Committee (Subcommittee of Ethics) of the Spanish Research Council, ref. no. 036/2021, 04/19/2021.  
**Informed Consent Statement:** Informed consent was obtained from all subjects involved in the study.  
**Data Availability Statement:** All materials, data and associated protocols used in this work are available to interested readers.  
**Acknowledgments:** All the work, supplies, and expenses have been kindly provided from the scientists and participants participating in the study. We are grateful to [PERSON] for building the structure, to the Director of the Institute Cajal for his support to the project and managing the outside booth housing the maze, to [PERSON] from the Infrastructure Department of Institute Cajal for the setup and building the booth, to [PERSON] from the Neural Rehabilitation Group of the Institute Cajal for his support to the project facilitating the access to the high performance computer, to [PERSON] and [PERSON] from the Institute Cajal, for their help with the research, to A2 Colores staff for the graphics of the maze, and to all the participants participating in the study.  
**Conflicts of Interest:** The authors have no conflict of interests to declare.