Consciousness is at the very core of what makes our waking perception of reality. We are able to process all that sensational data given and make it a coherent image of our world. That consciousness is what gives us the ability to be the highly successful albeit complex species we are.
But what does all this mean. What is our brain doing while we busily process all this data that makes our perception....well conscious. Other animals don't have the level of perception that we have. The ability to not just recognize what we see as food or threat, but see a situation and understand our hand in it and how that situation came to be without necessarily observing the cause. To get an idea of what that process is we need to compare the waking mind to that of a state of unconsciousness. While we sleep our brains are still active. this has been shown in many previous studies. The mind however active is definitely not conscious. This sleeping "condition" present researchers with a comparable state to make their observations. Researchers at the University of Wisconsin and Milan have devised a way to look at the activity of the brain to direct stimulus under the two different conditions.
By wearing a set of electrodes the researchers are able to apply a shock to the brain by a process called Trans Cranial Magnetic Stimulation (TMS). As the shocks are applied the electrodes are able to sense the activity of the brain. IN the conscious mind the responses are wide spread stimulating areas all over with complex patterns associated with each individual area stimulated. In contrast the unconscious mind, or sleeping, has only localized responses. This suggests that the mind has a great deal more connections while it is conscious and that those connections are very wide spread and diverse based on the stimulus. To be clear that a more interconnected and communicative mind is a more conscious one.
This study while relatively simple gives a pretty clear indication of what a conscious mind looks like; lots of communication and signal responses all over the mind and variable based on stimulus. The intriguing bit about this is that we know have a clearer picture of what consciousness looks like and may be able to perceive the level of consciousness in other creatures.