Dr Anup Bende sir yes sir you are right much force is required for concussion. I meant to say is when a person is scared from something an instant reaction comes to protect yourself same happened to me when someone was splashing water at me my body just sent immediate reaction so my head was straight at the moment when water was splashed a sudden reaction came my eyes became closed and head moved a bit to right side and I felt like something inside my head has moved kind of like jelly has moved inside my head at top.