Hello, I just implemented a SOM algorithm in MATLAB that outputs component planes and U matrix....but i want to be able to calculate sensitivity, accuracy and specificity....how do i go about doing this in MATLAB??....any ideas or useful links would be highly appreciated??

It would have been much better if you had rephrased your first question in the light of the answers you already got and responding to the comments you got. Something like: "Methods to turn a SOM into a supervised classifier/predictor" Because that is the first step and requires a bit more than just implementing functions to calculate these values. I assume that in the end you just want a good classifier. Why exactly use a SOM? Even with lots of tuning and reasoning to turn the SOM into a supervised classifier it will still be inferior to any out-of-the-box support vector machine (SVM).