{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,23]],"date-time":"2026-07-23T02:33:19Z","timestamp":1784773999721,"version":"3.55.0"},"reference-count":43,"publisher":"MIT Press","issue":"9","license":[{"start":{"date-parts":[[2025,7,24]],"date-time":"2025-07-24T00:00:00Z","timestamp":1753315200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":["direct.mit.edu"],"crossmark-restriction":true},"short-container-title":[],"published-print":{"date-parts":[[2025,8,8]]},"abstract":"<jats:title>Abstract<\/jats:title>\n               <jats:p>Degeneracy\u2014the ability of different structures to perform the same function\u2014is a fundamental feature of biological systems, contributing to their robustness and evolvability. However, the ubiquity of degeneracy in systems generated through adaptive processes complicates our understanding of the behavioral and computational strategies they employ. In this study, we investigated degeneracy in simple computational agents, known as Markov brains, trained using an artificial evolution algorithm to solve a spatial navigation task with or without associative memory. We analyzed degeneracy at three levels: behavioral, structural, and computational, with a focus on the last. Using information-theoretical concepts, Tononi et\u00a0al. (1999) proposed a functional measure of degeneracy within biological networks. Here, we extended this approach to compare degeneracy across multiple networks. Using information-theoretical tools and causal analysis, we explored the computational strategies of the evolved agents and quantified their computational degeneracy. Our findings reveal a hierarchy of degenerate solutions, from varied behaviors to diverse structures and computations. Even agents with identical evolved behaviors demonstrated different underlying structures and computations. These results underscore the pervasive nature of degeneracy in neural networks, blurring the lines between the algorithmic and implementation levels in adaptive systems, and highlight the importance of advanced analytical tools to understand their complex behaviors.<\/jats:p>","DOI":"10.1162\/neco.a.19","type":"journal-article","created":{"date-parts":[[2025,7,24]],"date-time":"2025-07-24T15:05:03Z","timestamp":1753369503000},"page":"1677-1708","update-policy":"https:\/\/doi.org\/10.1162\/mitpressjournals.corrections.policy","source":"Crossref","is-referenced-by-count":1,"title":["From Function to Implementation: Exploring Degeneracy in Evolved Artificial Agents"],"prefix":"10.1162","volume":"37","author":[{"given":"Zhimin","family":"Hu","sequence":"first","affiliation":[{"name":"Department of Psychiatry, University of Wisconsin\u2013Madison, Madison, WI, 53719, USA hu436@wisc.edu"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"O\u011fulcan","family":"Cingiler","sequence":"additional","affiliation":[{"name":"Institute for Physiology, Universit\u00e4t Bonn, Bonn, Germany, 53151 ocingiler@gmail.com"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Clifford","family":"Bohm","sequence":"additional","affiliation":[{"name":"Department of Integrative Biology, Michigan State University, East Lansing, MI 48824, USA cliff.bohm@gmail.com"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Larissa","family":"Albantakis","sequence":"additional","affiliation":[{"name":"Department of Psychiatry, University of Wisconsin\u2013Madison, Madison, WI, 53719, USA albantakis@wisc.edu"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"281","published-online":{"date-parts":[[2025,8,8]]},"reference":[{"key":"2025080816010598900_bib1","doi-asserted-by":"crossref","first-page":"87","DOI":"10.4324\/9781315205267-6","article-title":"Integrated information theory","volume-title":"Beyond neural correlates of consciousness","author":"Albantakis","year":"2020"},{"issue":"11","key":"2025080816010598900_bib2","doi-asserted-by":"publisher","DOI":"10.3390\/e23111415","article-title":"Quantifying the autonomy of structurally diverse automata: A comparison of candidate measures","volume":"23","author":"Albantakis","year":"2021","journal-title":"Entropy"},{"key":"2025080816010598900_bib3","doi-asserted-by":"publisher","DOI":"10.1371\/journal.pcbi.1011465","article-title":"Integrated information theory (IIT) 4.0: Formulating the properties of phenomenal existence in physical terms","volume":"19","author":"Albantakis","year":"2023","journal-title":"PLOS Computational Biology"},{"issue":"12","key":"2025080816010598900_bib4","doi-asserted-by":"publisher","DOI":"10.1371\/journal.pcbi.1003966","article-title":"Evolution of integrated causal structures in animats exposed to environments of increasing complexity","volume":"10","author":"Albantakis","year":"2014","journal-title":"PLOS Computational Biology"},{"issue":"5","key":"2025080816010598900_bib5","doi-asserted-by":"crossref","DOI":"10.3390\/e21050459","article-title":"What caused what? 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