Day: February 21, 2001

Concept Maps Are Confusing

An Associated Press story about concept mapping is making the rounds and getting a lot of attention from the usual suspects. The story discusses work at the Institute for Human and Machine Cognition designed to find a better way to browse information on the web.

IHMC associate director Alberto Canas wants to know, “Why should we organize it as pages? There’s no reason. It’s just that we’re used to it.” He thinks it would be much easier to browse concept maps that provide a graphic representation of a subject and all its related subjects.

I think Canas is on the wrong track. Concept mapping or mind mapping or whatever you want to call it is an excellent way to brainstorm or for individuals or groups to begin to find ways to organize information they already have, but for general use concept maps are extremely confusing and almost useless in my experience as everyday navigation tools.

One of the existing concept maps the Associated Press mentions, for example, is NASA’s concept map for its Center for Mars Exploration, which nicely illustrates everything that is wrong with concept maps.

If I’m a science teacher wanting to organize my thoughts about all of the issues surrounding a Mars expedition for a class unit, constructing a concept map like that is probably a pretty good way to lay out the various things I might want to cover. But if I’m a reader who knows little about Mars exploration, this gives me way too much information.

More importantly the concept maps don’t do a good job of providing proper context for information. I have no idea how important any given choice on the map is nor how relevant it is likely to be to any specific questions I have (unless I happen to view the world in precisely the same way that the person who put together that map does).

On the other hand, compare that to the front page of The Whole Mars Catalog. I’m not sure that the simple list of links is all that more helpful, but it provides essentially the same ultimate navigational tools without being completely overwhelming with arrows pointing everywhere.

I seriously doubt that concept maps will ever be widely used for web navigation.

Jimmy Carter on the Mark Rich Pardon

Most of the Democrats on the weekend news shows were taking the line that Bill Clinton’s pardon of Mark Rich was deplorable but there was no evidence that Clinton pardoned Rich because of campaign contributions he received from Denise Rich.

Former President Jimmy Carter disagrees, telling the Associated Press, “I don’t think there is any doubt that some of the factors in his pardon were attributable to his large gifts. In my opinion, that was disgraceful.”

Way back in 1992, Clinton promised that his time in office would represent “the most ethical administration history.” The one thing I would really like to see a reporter ask Clinton point blank is whether he believes he achieved that goal (and I suspect that despite everything he would answer in the affirmative).

Researchers Find Mice Bone Marrow Cells Can Transform into Neurons

Researchers at the National Institute of Neurological Disorders and Stroke published an article in Science in December 2000 reporting on a very surprising finding — bone marrow injected into mice were able to transform themselves into brain cells.

Bone marrow consists of a couple of different types of stem cells which are the source of blood cells in the body. Scientists knew that neural stem cells can transform themselves into muscle, but the accidental discovery that bone marrow stem cells can transform into neurons was a major surprise.

In fact the researchers weren’t even investigating that possibility in their initial experiments. They had injected mice with a genetically altered form of bone marrow that contained a gene that made the stem cells glow in the dark. The researchers were investigating whether or not the stem cells would convert themselves to muscle cells in the mice.

When they performed the dissection of the mice, however, they were surprised to find the animals’ brains contained neurons that now glowed in the dark. Several other experiments, some involving a second laboratory, were done to confirm that in fact the bone marrow was replacing neurons.

Helen M. Blau, senior author of the Science article, told the Associated Press that, “It may be a repair mechanism that is going all the time at a low level.” The bone marrow probably doesn’t work at a high enough level to repair serious brain damage or disease, but it may be on ongoing way that the body replace dying or defective neurons.

A lot more research will need to be done to better understand what is going on here, and this may never lead directly to any treatment for neurological disorders, but it does add an important piece of the puzzle on how adult stem cells can differentiate into a wide variety of other cells which is of great importance in many current efforts to find treatments for Alzheimer’s, spinal cord injuries, and a whole host of other ailments.

Source:

Mice marrow can net neurons. Associated Press, December 1, 2000.