I don't think that our lives are predetermined. I have looked at particles that can be utilised by our own sentience at such a speed that according to nature they are in two states at once.
A spinning particle is a cog. We spin the cog sentiently. The cog can turn clockwise or anti-clockwise. I think we use this cog to begin our physical thought process.
Read this......
"spooky action at a distance,"
http://whyfiles.org/shorties/133quantum_leap/
Then I need to say that the cause of the spin in the particle was created by observation. However, there was no cause for the direction of the spin. The direction of the spin was a decision made by the particle itself. Now this decision is somehow connected with sentiency. We need to find out exactly what sentiency is, because here we have a case where observation is transmitted as a form of perpetual motion. A spin without energy transmission. When I touch my nose, I could infact say that I am observing my own particles to make them rotate, to open gates that control the flow of electrons. The movement could just be based on the initial spin direction which was observed in the physical test in the link. If these particles have no history, and only become active through observation, and observation is based in the present then you could say that sentiency is to be aware of the present, and only live in the present.
Now to carry this a bit further.. light is another element that requires observation to become active. Observation is a sentient force, but light is reaching the Earth from a distance that is so far away that the light is reaching Earth before sentient life lived here. This is a case for sentience from something other than molecular life forms. How low level can sentience get? So I observe the particle, and maybe pass my sentience to the particle so that it can make a decision of which way to spin.
according to the thread, the particle was spinning in both directions at once, a sort of .. no state. And as soon as it was observed it took a state. The opposite state was passed to its twin faster than the speed of light.. infact.. instantly. Now, a decision that is instant, is surely what we search for with sentience, and surely has no time for cause to take place. Anyway it is interesting, so I have made a little picture for what I call sentience...

Two states for every passage of time. It breaks the linear universe way of thinking.
Sentience is its own cause. Sentience pushes the car, but nothing pushes sentience. when we observe a particle, we are the observer. Nobody else is observing the particle. Therefore, we have our own sentience, which should also be able to have effects on the particles in our own brain. I presume that the particles in our brain are rotated similar to the experiment. Maybe to create gateways for the electrons to pass through...Instantly!

The leaf floats down from a tree, obeying the cause, and effects of nature. I can grab the leaf using sentience, and alter the linear state of the leaf's path, and break the linear state of the universe. I know this because Time gives me two options during every tick of nature's clock. I know this because a particle can be in two states during any tick of nature's clock, and I can utilise this particle through observation, and I can do it instantly.
Now you can rewind nature's tapes, and you will not get the same outcome a before. The spinning particles can go anti-clockwise whereas before they went clockwise.
If sentience recieves repetative information, as an effect of its cause, the spinning particles will also revert back to their initial repetative 0/1 dual state. This means that we need to percieve new experiences for as long as possible in our lives. Else we revert back to a state of nature. Where nature takes over our bodies, and we become a sort of zombie, that lives the repetition without aid from sentience. Like a tiger pacing up, and down its cage. The brain has developed its own protection about reverting back to nature. It gives us an interest in entertainment, and a pain from certain things like boredom.