Can you scientifically define the idea of 'consciousness'?

Question

I'm curious what the scientific indicators of self-awareness / consciousness are - if there are any.

Thanks!

Answer 1

Good question, but tough one. Depending on who you ask these terms are differently defined. Some will argue that self-awareness is not self-consciousness, and that there is a difference between consciousness and self-consciousness. Others use all three terms synonymously. For science the concept of consciousness has long been a taboo, since it was thought to be a mere epiphenomenon of brain states that therefore escapes empiric analysis. But lately scientists together with philosophers ask the question of consciousness, and so there are a few scientific perspectives on the problem. However, if you are looking for conclusive definitions that are generally agreed on you will be disappointed.

Generally, the other posters have already nicely summed up some of the main ideas of what self-awareness or consciousness is about. It is a notion of self vis-a-vis other. In other words, my dog knows that its paw belongs to itself and not to me. If you compare my dog to a sea anemone the concept might become clearer. Sea anemones attack other organisms as soon as their tentacles make contact. In their tentacles anemones have specialized cells, so called cnidocytes, which contain an inner filament and an external sensory hair. Contact with the hair mechanically triggers the cell to shoot out a harpoon-like structure, which penetrates the skin of the organism that touched it. Then, a poison is injected into the aggressor or prey. In order not to hurt itself, the anemone constantly applies a secretion it produces in a specialized glad to its own tentacles. The secretion protects the tentacles from inducing the cnidocytes response when they touch one of the anemone’s other tentacles. Obviously, the anemone is not self-aware.

A scientific key to a different kind of self-awareness that in dogs became available in the early 1970s with Gordon Gallup’s famous mirror image self-recognition (MSR) experiments on chimpanzees. He found that the chimpanzees were able to recognize themselves in the image they saw in a mirror, whereas monkeys (or dogs) were not. He consequently concluded that there is cognitive step between monkeys and apes, a conclusion that seemed to be supported by later research on other great apes and monkeys. However, MSR tests are more complicated than Gallup’s initial work suggested. For one, they have to be given in a context that “makes sense” for the species in question. When experimental designs were adjusted, even gorillas, which failed the test initially, past it successfully. Moreover, research on bottlenose dolphins and African elephants showed that MSR was not exclusively reserved for hominids, but that it marks a case of cognitive convergence. It is therefore to be expected that more species than initially anticipated evolved cognitive abilities of self-awareness, and that self-awareness has evolved more than once.

Big deal, you might say; your dog can tell its own paw from your foot, so where’s the big deal in a few critters being able to recognize themselves in the mirror? The thing is that MSR suggests that apes and dolphins and elephants can actually have a more abstract notion of self than a dog. (Caveat lector: it might of course be that future research will make this example superfluous and you would have to put in another species here…) Somehow MSR positive animals are capable of making the connection between the body they see in the mirror and their own body. They check the inside of their mouth (in case of chimps) because they recognize that this is their mouth they see. In fact, they check all sorts of body parts otherwise out of sight for them. Is this difference then big enough to speak of consciousness? That depends largely on your definition.

One scientist to attempt a definition of consciousness is neuro-biologist Antonio Damasio. As you will see, the definition is in many ways more a philosophical one:

“How do we ever begin to be conscious? Specifically, how do we ever have a sense of self in an act of knowing? We begin with a first trick. The trick consists of constructing an account of what happens within the organism when the organism interacts with an object, be it actually perceived or recalled, be it within body boundaries (e.g., pain) or outside of them (e.g., a landscape). This account is a simple narrative without words. It does have characters (the organism, the object). It unfolds in time. And it has a beginning, a middle, and an end. The beginning corresponds to the initial state of the organism. The middle is the arrival of the object. The end is made up of reactions that result in a modified state of the organism.
We become conscious, then, when our organisms internally construct and internally exhibit a specific kind of wordless knowledge – that our organism has been changed by an object – and when such knowledge occurs with the salient internal exhibit of an object.”

Philosopher John Searle offers this definition:

"Consciousness consists of inner, qualitative, subjective states and processes of sentience and awareness. Consciousness, so defined, begins when we wake in the morning from a dreamless sleep and continues until we fall asleep again, die, go into a coma, or otherwise become 'unconscious.'"

According to these definitions, we can actually conclude that MSR positive animals might also be conscious. One major step to consciousness however, would be whether animals possess a theory of mind (TOM). One way that we could assign consciousness is by measuring behavior assuming that a behavior we normally exhibit in a conscious state would suggest consciousness in an observed organism if present. One such a behavior could be speech. But here is the problem, as Searle points out: Your radio is exhibiting speech… Would you therefore think it to be conscious? Obviously not! This is because you have a theory of mind. Based on your own experience of yourself you will assign a conscious mind to another human being when it interacts or acts. Now, a TOM is thus important to RECOGNIZE consciousness, but it is equally important to HAVE consciousness. For, it marks an entirely different cognitive quality to be capable of a theory of consciousness in another individual.

TOM has been shown in chimpanzees, and so it seems at least somewhat, if not highly possible that chimps are conscious.

As you can see, it’s a problematic issue – and very complex. I stop here, but if yu have further questions, see the literature!

Answer 2

I'm not going to give a philosophical or social science definition. Basically, consciousness is a state of awareness of self and environment. Some medical indicators include whether or not there is a sleep/wake cycle, circadian rhythm (any stimulation to light?), purposeful movement, verbilization or communication, eyes remaining closed, and response or localization to painful or noxious stimuli. Other things to consider are whether their reticular activating system is fully functioning, and what their EEG looks like. Extensive lesions of the brain can cause permanent altered states, and this may be fatal.

Answer 3

Self-awareness is generally seen as being the ability to recognize "self" from "not self". For instance, great apes (chimpanzees, gorillas, orangutans, humans) can look in a mirror and realize they are looking at themselves.

In humans, this develops at about age 2 or 3. Before that age, babies do not know they are a separate thinking entity. This has been tested by having these young children see something being hidden away and not realizing that another person who hasn't seen the hiding being done won't know where to look.

After that age, it is likely "sense of self" comes from unique memories and also from stories we all make up about ourselves.