The Brain and Interpretation of Thought

I wanted to get your opinions on how thought manifests to a form that we have come to know.

Scientist says that neurons fire in certain spots when we think; now correct me if I'm wrong but this is a similar concept of a computer. When a computer is trying to "think" or process, the processor turns switches on and off, firing electricity down the pipeline. No matter what a computer tries to do, it will use predefined functions and variables to accomplish the task of converting the switch patterns to something we can understand.

Now back to the brain, if we have a thought of a "tree", our neurons will fire to process this thought. Now how does our brain know that those neurons that fired is a tree? In reality it is just neurons firing, but to us, it is a thought. How does a neurons firing process into a thought that we are familiar with?

Is there an immaterial part of life that makes sense to us the material part? Something that says that these 2,000 neurons that fire will be a tree?

I would like to hear your opinions because I don't know what to think about this, I'm still in the questioning stage when it comes to this topic. I may have it all wrong so please let me know.