Fear slows you down. Fear of the machine. Fear for the machine. Fear for yourself.
To be able to drive at 10/10ths of your talent all of this must be conquered.
You cannot fear the machine. You must respect it and know the limits of it, but you cannot fear it.
You cannot fear for the machine. This does not mean to drive recklessly or intentionally do things that can damage it, but you cannot fear damage to the car.
You cannot fear for yourself. This does not mean to drive without thought to safety. Take as much care to protect yourself as you deem necessary, then trust in the equipment.
When the fear is gone, the mind is free to focus on the speed.
Look at Senna. In the rain, other drivers had fear. They were afraid of the rain, of their machines. Senna knew his limits, and felt no fear.