Science avoids the question of “What is Consciences?”; this question and other existential questions are left to Philosophers and meta-physics. Religion avoids these questions, too.
One way to tackle the question and bind several disciplines is to think of our brains as Quantum Computers and model our free-will choices as quantum decoherence. In other words, our choices “collapse” the multi-verse into our perceived reality.
There needs to be scientific proof for this Analytic approach to Existentialism. Neither is it proved that it is possible to choose a collapse of a wave function. Following this thinking, our choices may be more random than we think.