This is a behavioral modification term related to not rewarding bad behavior which comes from dolphin trainers. A recent New York Times article on animal trainers was written by Amy Sutherland (June 25, 2006). http://www.nytimes.com/2006/06/25/fashion/25love.html?pagewanted=all&_r=0
We all know that animal trainers immediately reward a desired behavior with a small food treat. Dolphin trainers at Sea World San Diego use a term they call least reinforcing syndrome (L.R.S) when a dolphin exhibits an undesirable behavior or does something wrong.
The trainer does not respond at all. The trainer stands still, does not look at the dolphin and after a short time goes back to the work of training.
The basic psychological principle behind this is that ANY response from the trainer whether a positive or a negative response reinforces the behavior. If there is no response from the trainer the behavior is likely to be extinguished, to go away.
Sutherland’s article explains that she has tried this effectively with her husband, and subsequently others have tried it effectively on dogs and small children.