Conclusion and future directions
Recent studies from human brain imaging and animal experiments have
provided new insights into consciousness. Among several possible
mechanisms, the thalamus projection to the brain is thought to be the
core mechanism. Excitatory transmission and plasticity may play
important roles in consciousness. Inhibitory transmission contributes to
excitatory/inhibitory balance, thus, also controls consciousness.
Studies using different experimental approaches reveal possible
selective circuits (by optogenetic) and proteins (by gene manipulation
and chemicals). From a basic research point of view, the future needs to
reveal molecular and cellular mechanisms for the neuronal mechanism of
consciousness. Animal experiments during anesthesia at least provide a
good animal model for such studies. For clinical application, deep brain
stimulation will only help to understand consciousness in humans, but
also help patients with DOC. More importantly, how learning may affect
the level of consciousness of human beings will be a vital question for
neurons as well as society. Maybe that is an evolutionary force for
human beings as well. High levels of consciousness due to constant brain
learning may lead to prolonged life of the brain. Many brains decide to
give up hope for life, at least in part, due to poor levels of
consciousness during aging.