Preface for the Special Issue of Mathematical Biosciences and Engineering containing six selected papers based on the contributions presented at the Neural Coding Workshop 2018 held in Torino, Italy, between September 9 and September 14, 2018. This was the 13th of the successful biennial Neural Coding conference series, after the previous workshops in Prague (1995), Versailles (1997), Osaka (1999), Plymouth (2001), Aulla (2003), Marburg (2005), Montevideo (2007), Tainan (2009), Limassol (2010), Prague (2012), Versailles (2014) and Cologne (2016). Further information on the 2018 workshop, including the book of abstracts and the list of participants, can be found at http://www.neuralcoding2018.unito.it/. The selected articles illustrate well the broad methodological scope used in the field and also show how different theoretical models and concepts may relate to each other.