The problem for scientific models of consciousness remains accommodating these intuitive accounts within a materialist framework consistent with the findings of neuroscience. While there is no current scientific explanation for how brain tissue generates or maintains subjective experience, the consensus among (most) neuroscientists is that it is a product of brain processes.

If that’s the case, why did consciousness, defined as subjective awareness, evolve?

Consciousness presumably evolved as part of the evolution of the nervous system. According to several theories the key adaptive function (providing an organism with survival and reproductive benefits) of consciousness is to make volitional movement possible. And volition is something we ultimately associate with will, agency and individuality. It is therefore easy to think that consciousness evolved to benefit us as individuals.