用電腦一時後，為何甚麼也想不出來必須休息後才有思維?

one cannot think too much on other issues when concentrated on something, same case for using computers, which involve the eyes, hands, may be mouth and ears as well if one is voice chatting or making phone calls through PC/internet ; and one can recover after rest, be it long or short, depending on individual and can think, using the brain then