My early work in this area addressed the problems of using text-based programming languages. I showed that structured programming, which at that time was the conventional wisdom, was only partly correct, being based on a limited view of human cognition, and I demonstrated large usability differences between two equally-well-structured notations; such effects can obviously not be explained by the principles of structured programming. Considering the match between the surface comprehensibility of the programming language and the task the programmer was trying to achieve gave a much better account of the evidence: I called this the "match-mismatch" law. In general, every notation or information structure highlights some information at the cost of obscuring other information.
With the recent growth of interest in graphical or visual programming, Marian Petre and I have performed complementary studies showing that the "match-mismatch" law applies to graphical programming languages just as it does to textual ones, and that it applies to professionals, novices, and intermediates.
Here are some publications of mine in this area. (See the page on 'cognitive dimensions of notations' as well.)
Green, T. R. G. (1997) Cognitive Approaches to Software Comprehension: Results, Gaps and Limitations. Extended abstract of talk at workshop on Experimental Psychology in Software Comprehension Studies 97, University of Limerick, Ireland.
Petre, M., Blackwell, A. F. and Green, T. R. G. (1997 in press) Cognitive questions in software visualisation. In Stasko J., Domingue, J., Price, B., Brown, M. (Eds.) Software Visualization: Programming as a Multi-Media Experience. MIT Press. Fetch RTF
Davies, S. P., Gilmore, D. J. and Green, T. R. G. (1995) Are objects that important? The effects of expertise and familiarity on the classification of object-oriented code. Human-Computer Interaction 10 (2 & 3) 227-248.
Green, T. R. G. and Navarro, R. (1995) Programming plans, imagery, and visual programming. In Nordby, K., Gilmore, D. J, and Arnesen, S. (1995) INTERACT-95. London: Chapman and Hall (pp. 139-144)
Hendry , D. G. and Green, T. R. G. (1994) Creating, comprehending, and explaining spreadsheets: a cognitive interpretation of what discretionary users think of the spreadsheet model. Int. J. Human-Computer Studies, 40(6), 1033-1065.
Hendry, D. G. and Green, T. R. G. (1993) CogMap: a visual description language for spreadsheets. Journal of Visual Languages and Computing, 4(1), 35-54 (special issue on cognitive aspects of visual languages)
Petre, M. and Green, T. R. G. (1993) Learning to read graphics: some evidence that "seeing" an information display is an acquired skill. Journal of Visual Languages and Computing, 4 (1), 55-70 (special issue on cognitive aspects of visual languages)
Green, T. R. G. and Petre, M. (1992) When visual programs are harder to read than textual programs. In G. C. van der Veer, M. J. Tauber, S. Bagnarola and M. Antavolits (Eds.) Human-Computer Interaction: Tasks and Organisation, Proceedings of ECCE-6 (6th European Conference on Cognitive Ergonomics). CUD: Rome.
Green, T. R. G., Gilmore, D. J., Blumenthal, B., Davies, S. and Winder, R. (1991) Towards a cognitive browser for OOPS. International Journal on Human-Computer Interaction 4(1), 1-34.
Green, T. R. G., Petre, M. and Bellamy, R. K. E. (1991) Comprehensibility of visual and textual programs: a test of Superlativism against the "match-mismatch" conjecture. In J. Koenemann-Belliveau, T. Moher, and S. Robertson (Eds.), Empirical Studies of Programmers: Fourth Workshop. Norwood, NJ: Ablex. Pp. 121-146.
Hoc, J-M., Green, T. R. G., Gilmore, D.J. and Samurçay, R. (Eds.) (1991) The Psychology of Programming. London: Academic Press.
Green T. R. G. (1991) Programming languages as information structures. In J-M. Hoc et al. Psychology of Programming. Academic Press .
Green, T. R. G. (1991) The nature of programming. In J.-M. Hoc et al., Psychology of Programming. Academic Press.
Green, T.R.G., Bellamy, R.K.E. and Parker, J.M. (1987) Parsing and Gnisrap: a model of device use. In G. M. Olson, S. Sheppard and E. Soloway (Eds.) Empirical Studies of Programmers: Second Workshop. Ablex.