This should be
possible, unless a current theory (and almost any
religion) is
true.
A current theory has been gaining acceptance that states that human consciousness is derived from quantum mechanal interaction inside each neuron's microtubules within the brain. I am fond of this theory if only to deny the logical endpoint of thought as a derivitive of purely Newtonian physics.
The brain without quantum mechanics interfering would be a complex machine only able to react to stimuli, which was caused by something else and so on. This would suggest that everything is predetermined by one initial action at the universe's creation, or Fate or God.
However, if the quantum microtubules theory is true then there is free will. It would also make simulation of a human brain dificult if not impossible. A quantum computer would be required, and even then, the seeming randomness of quantum states may preclude any type of artificial "soul".