I wear earplugs to help concentrate. When co-workers chat it does not interrupt my flow. If someone speaks directly to me I can usually detect it. If I make the

I wear earplugs to help concentrate. When co-workers chat it does not interrupt my flow. If someone speaks directly to me I can usually detect it. If I make the decision to remove the orange foam in my ears I give that person my full attention. I sympathize with your situation. I wonder if it would do any good to challenge each person who taps your shoulder. How about: "You really startled me. I was concentrating and your touch felt like a lightening bolt. No harm done but in the future would you mind approaching my desk more from the front? I'd really appreciate it. So would my cardiologist."