Recently, we looked at consciousness from the perspective of Joseph LeDoux’s recent book, A Deep History of Ourselves (1919). Psychologist Lisa Feldman Barrett situates his work at Nature, offering an interesting qualification:

LeDoux, an academic at New York University in New York City, is best known for his research on fear, and for carefully mapping the brain circuit centred on the amygdala — a knot of neurons in the medial temporal lobe. The amygdala, he showed, has a crucial role in non-conscious, defensive behaviour responses such as freezing or fleeing. His conclusion, based on the assumption that all mammalian amygdala circuits are structurally similar, was that all mammals (including humans) share these responses. He described this work in The Emotional Brain (1996).

In the meantime, the amygdala circuit was referred to as the ‘fear circuit’. This became problematic. The mislabelling, LeDoux realized, had fuelled a misconception: that humans and other mammals share the conscious experience of fear (that is, the feeling of fear), not just non-conscious, defensive behaviours. In fact, he has long argued that, on evidence, the amygdala circuit is not sufficient, and might not be necessary, for feeling fear; that role, he suggests, is filled by parts of the prefrontal cortex involved in working memory.

Lisa Feldman Barrett , “Survival: the first 3.8 billion years” at Nature (August 20, 2019)

He later relabeled amygdala circuits as “survival circuits” and used the term “fear” only for “the conscious experience of fear” (Barrett), particularly, we are told, in his later book, Anxious (2015).

That was a wise move on Dr. LeDoux’s part. The feeling of fear, as a human being understands it, is partly concrete but also partly abstract. We humans have many of the same fears as dogs or cats. But we have some fears they don’t have. We fear pain and loss. But we also ask “What will happen to my loved ones if I die?” What will happen to me when I die? “What will happen if my friend dies?” and “What will happen if my country is engulfed in a civil war?”

Animals simply don’t think of these things. Their experience of fear may be more acute than ours — because it is not mitigated by any philosophy — but it is also much less complex.

Barrett goes on to note,

LeDoux is at his best when thoughtfully considering some of neuroscience’s more contentious topics. He revisits the question of consciousness in non-human animals, concluding that if it exists, it is very different from our own. He muses on why some scientists place humanity at the apex of intelligence on Earth, and mistakenly assume that evolution aimed itself at us. And he offers terrific examples of how the assumption of such a natural order in evolution (scala naturae, the idea that living things have a linear order, from simple to complex) is profoundly unhelpful to scientific progress.

Lisa Feldman Barrett , “Survival: the first 3.8 billion years” at Nature (August 20, 2019)

Well, wait. Humans are clearly the “intelligent” species on this planet. We change nothing by denying that. If other species do not benefit from our intelligence, we may hold ourselves liable. But we can’t make them what we are and pretending they are when they aren’t doesn’t help. Chimpanzees, for example, only survive today due to human intervention.

But — setting aside for a moment human abilities like abstraction — how different is animal emotional consciousness from human emotional consciousness? Doesn’t that depend very much on the animal? Dogs, cats, and horses, for example, have emotions that humans can easily understand. That’s why we all live together. Dogs, cats, and horses can tell us when they are unhappy and we can usually guess why. Love, hate, jealousy, envy … they are not strangers.

If lichens, sand dollars, and ferns have emotions, we might have a hard time understanding what their emotions are and what we could possibly do about them.

There’s no escape from human destiny by pretending that somehow we aren’t really the “intelligent” species on the planet., There are no other applicants for the role.

You may also wish to read: Consciousness is mainly a problem for materialists, a reflection on an except from LeDoux’s book, A Deep History of Ourselves (1919).