Several animal species may possess sentient awareness, but they can't let us know one way or the other.
There is still much we don't understand about the nature of consciousness, how it first came about and why.
One theory suggests that everything in the universe, even the chair you are sitting on, has some level of consciousness.
Some of the most fundamental questions of existence and consciousness may be beyond the scope of conventional science.
Consciousness remains a fascinating enigma and the scientific community is unable to agree upon any one theory.
The nature of consciousness and whether or not it pervades the entire universe has long remained a topic of debate.
Neurophysiologist Par Halje looks at how research into psychedelics could help us understand consciousness.
More than 100 projects have been put forward in a bid to unlock the secrets of consciousness.
Researchers now believe that consciousness may persist for up to 20 seconds after a person has clinically died.
New research has revealed how the 'pleasure chemical' dopamine plays a key role in human consciousness.
Some scientists have speculated that consciousness could be the product of quantum processes.
For centuries, mankind has struggled to understand the precise nature of human consciousness.
We all make hundreds of decisions every day, but by how much are these influenced by unconscious factors ?
Scientists have identified an area of the brain that seems to be strongly connected to consciousness.
The question of exactly what consciousness is has puzzled philosophers and scientists alike for millennia.
Scientists have warned that miniature brains grown in the lab may have become conscious and could be suffering.
It turns out that staring into someone's eyes for ten minutes can induce an altered state of consciousness.
For years, scientists have clashed over whether or not plants possess a form of conscious awareness.
A recent experiment has called in to question our understanding of when a person's brain has truly 'died'.
Scientists have been trying to find a way to definitively determine if a brain injured patient is conscious.