Immune system teaches software

Computer experts at Aberystwyth are using the human immune system as the model for software that could radically improve computers' capacity for learning.

"The immune system is a naturally occurring learning system that protects the body from disease by identifying the pattern of infectious foreign substances, or antigens, and then creates antibodies that bind to the various antigens and destroy them,'' said John Hunt of the Centre for Intelligent Systems at the University of Wales in Aberystwyth.

"As far as computer software is concerned, the crux is that the system not only instantly recognises familiar antigens and neutralises them but will also allow immunity to fade when no longer required."

With microbiologist Denise Cooke, Dr Hunt developed a program which generates small pieces of computer code that take on the role of antibodies. The antigens are represented by the tasks that the program is trying to carry out. The software antibodies must try to match the requirements of these tasks.

"With the natural immune system you have to go back to the doctor every few years to get re-immunised with shots,'' said Dr Hunt. "This gave us the clue because in a computer-based learning system being able to forget little-used information is very important. Neural networks or case-based reasoning systems, for example, can easily get too specialised and so sidetracked because they can't forget anything."