I am currently haunted by this question and I am writing here the leads that I found that may answer this profound problem.
My knowledge of how the brain works is quite superficial. I have always thought that the links are important as indexes for the brain, so that the entire semantic network need not be modeled in long term memory.
Indexing external semantic networks in memory
The indexes are either keywords, url, people you know, that will give you a semantic network. The semantic network's nodes may already exists in long term memory. It is the links that may be weak and even in danger of disappearing (forgetting). The equivalent or similar mental network in memory may be connected by weak links, so there is a need for a trigger to fire these links. That trigger is the indexes which may draw the semantic network structure in working memory and remind the brain of the path of the links to fire.
The question is whether the concepts in the semantic network of the external document is mapped in the declarative (semantic, episodic) or procedural memory in the cognitive architecture. Another is how many times do we need to keep drawing the external semantic network (e.g. asking a friend, rereading a blog) in order to strengthen the links and reduce the centrality or importance of the index.
Of course this is just my guess, I don't know whether this is true, I don't have any idea. But there may be a way to find out.
Simulating the CCK08 Moodle Forums
I am not a neuroscientist and the closest I can study a living brain is an artificial one. Fortunately cognitive scientists have developed cognitive architectures which are agents that tries to model the brain. One of these is Soar. I find Soar fascinating as it's underlying design of working memory is "organized as graph structures in states (Laird, 2008)". I was totally suprised to find nodes and links in their cognitive architecture. So I think it's not far fetched if someone has already found a way to relate this memory network to semantic networks and social networks. It's just a matter of time before I find those papers. Here is how I located the tools used in my on-going study of the CCK08 Moodle forums in Nigel Gilbert's diagram of the logic of simulation as a method (2005).
(based on Gilbert as cited in Gilbert & Troitzsch, 2005, p.17)
Ron Sun's Cascading Levels of Analysis
Although I have not fully read Ron Sun's "Cognition and multi-agent interaction (2006)" I found his idea of cascading levels of analysis providing some methodological meat to my skeleton of a general model of distance learning. I gather that he is advocating the integration of cognitive architectures and agent-based modeling in this book. He further states that "we may view different disciplines as different levels of abstraction in the process of exploring essentially the same broad set of questions (Sun, 2005)". His hierarchy of this different levels of abstractions are as follows:
Sun's Hierarchy of Four Levels
|Level||Object of Analysis||Type of Analysis||Model|
|1||inter-agent/collective processes||social/cultural||collections of agent models|
|2||agents||psychological||individual agent models|
|3||intra-agent processes||componential||modular construction of agent models|
|4||substrates||physiological||biological realization of models|
These levels looks similar to what I call modes in my skeletal model. And he further argue that we should engage in cross and mixed level analysis. I won't go any further on Sun's ideas since I still need to read the entire work, but I find it really exciting. His advocated approach may shed light on the problem of how linkages affect conceptual formation.
My skeletal model of distance learning
Laird, J.E. (2008, August 27). The Soar 9 tutorial. Part 1. Available in the software package here: http://sitemaker.umich.edu/soar/soar_software_downloads
Gilbert, N., & Troitzsch, K.G. (2005). Simulation for social scientist. (2nd ed.). England: Open University.
Siemens, G. (2009, July 30). Different Social Networks. Retrieved, August 9, 2009, from
Sun, R. (2006). Cognition and multi-agent interaction. From cognitive modeling to social simulation. Cambridge: Cambridge University.