The first phase of Dr William Edmondson's career moved from a PhD in Electrical Engineering / Psychology (on the development of a vibrotactile speech training aid for the deaf) to work on sign language linguistics (and an MA in Theoretical Linguistics). The linguistics work overlapped with the next phase.
The second phase of his career focussed on teaching and research in Human-Computer Interaction, with involvement in teaching and research on Cognitive Science. This work overlapped with the third phase.
The third phase of his career, including movement into retirement from institutional employment, focussed on SETI (the Search for Extra-Terrestrial Intelligence). This work continues.
The most important publications in his career are the paper in Astrobiology in 2003, and the book on Cognitive Science published by Brill in 2017. For details, please see Dr William Edmondson's profiles on Google Scholar and Academia.edu.