Consciousness is a subjective, personal thing, so scientists who study it usually rely on people telling them what they are aware of. The problem is that infants are probably conscious, but without language they cannot tell us this. Animals like dogs, cats, octopuses, and perhaps insects could also be conscious, but they cannot tell us this either.
There are even problems with studying adult consciousness. People may not be completely sure of their own consciousness. Some philosophers and scientists believe that awake, attentive adults may be aware of much more than can be expressed in words.
Because of these problems, scientists in both science and philosophy have recently developed new methods to measure consciousness.
For example, researchers have developed the Natural Kinds approach to studying the consciousness of babies and young children. This involves studying the brains and behavior of adults when they are aware of something. From this, a list is created of all the behaviors and brain patterns that we exhibit when we are aware of something, but that are not present when we are not. Researchers call these “markers” of consciousness.
Patterns of brain activity called “event-related potentials” can be detected using brain scans. Scientists use this technique to identify brain patterns that are present when we consciously see something, but not when our perception of that thing is subliminal. Some scientists believe that these patterns can also be found in infants, and that this activity even becomes stronger as the child gets older.
However, developmental psychologist Andy Bremner and I have suggested that we should not rely on just one marker of consciousness. If many markers tell us that an infant is conscious, we can draw more confident conclusions about infant consciousness. Other potential markers that might work in infants include the ability to pay attention and remember an adult’s action and later imitate that action.
Animal consciousness
Animals pose another challenge for studying the mind. Most people believe that animals such as chimpanzees and dogs are conscious, but how far up the tree of life does consciousness extend from humans?
There is strong evidence that octopuses can feel pain. They will groom an injured arm and avoid places where they have had unpleasant experiences. However, the evidence for consciousness in insects such as bees or ants is less clear. How could we ever know? These questions are particularly pressing because they have consequences for our treatment of animals.
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Some philosophers have suggested that we should approach the problem of animal consciousness with a “theory-light approach.” We can’t just take the “correct” theory of human consciousness and then use it to decide which animals have consciousness, because nobody knows what the correct theory of human consciousness is. A 2022 review listed 22 different scientific theories of consciousness, and there are many more. These theories contradict each other in many ways.
This theory-light approach looks at all the scientific theories about consciousness and finds out which ideas they agree with. We can then use these to figure out which animals have consciousness.
For example, many scientific theories about consciousness agree that it is easier for an organism to think about something when it is conscious of it. According to this idea, the role of consciousness may be to serve as a link between an animal’s sensory perception and its higher-level cognitive abilities.
This research into the consciousness of babies and animals raises the question of whether AI systems, including robots, might have consciousness. The increasing presence of robots in our social and cultural lives forces us to grapple with difficult scientific questions about how similar their minds are to ours.
There seems to be an intriguing connection between the consciousness of animals and that of robots. One approach in robotics takes inspiration from swarms of insects such as ants and bees. If you want to develop a group of robots that can explore a wide terrain, you should look at organisms that have been doing so for millions of years. But if scientists and philosophers eventually discover that these insects are conscious, the question will be whether we should claim that the robots based on them are conscious too.
When it comes to the question of whether AI systems, including robots, can be conscious, we come across an old philosophical debate that has been raging since before the modern rise of AI and shows no signs of abating.
On one side of this debate, some researchers claim that robots cannot be conscious because they do not have a biological brain. This side emphasizes that the only consciousness we can be sure of is found in biological organisms, so there is no reason to assume that robots are capable of it.
The other side of the debate says that when AI systems such as robots become sufficiently similar to biological beings, then we should say that they have consciousness, even if they are made of metal and wire rather than flesh and blood. Until this philosophical debate can be resolved, we will not know whether consciousness is possible in AI and robots.
