Some researchers feel that learning systems should have some amount of disorientation and cognitive overhead in order to facilitate exploration and learning [Mayes et al., 1990]. They feel that while most researchers are concentrating on navigation through information space, very little work has been done on navigation through "conceptual space". They contend that simply following links to nodes does not necessarily provide effective learning - "they do not tell us ABOUT anything, but only WHERE it is."
In learning systems, disorientation in conceptual space is required sometimes in order to explore and learn. Thus, users need to be guided not only by system information but also by discovery. The issue of cognitive overhead has not been found significant in learning systems [Mayes et al., 1990]. The authors say, the very question "what to do next, will enrich the process of learning rather than detract from it." A learning-by-browsing system called StrathTutor was developed where the links were computed based on how the nodes were related to each other, conceptually, in terms of certain attributes. This not only allows navigation through conceptual space but also the ability to "interrogate" the system by designating a combination of attributes that are meaningful at a particular instant of exploration; the system will respond by giving the learner a guided tour of all nodes satisfying those attributes.
StrathTutor also provides another facility called the "quiz" where the learner is asked to play a game in which he or she is asked to identify the nodes that have common attributes. This helps the learner create his or her own personal view of the underlying conceptual space. The content search and structure search mechanisms, suggested by Halasz, will be especially useful in learning systems.