In Utero Limbo

The Prenatal Brain & the Sticky Question of Consciousness

When does an unborn child become conscious?

The human mind is unique in the known universe. We see evidence of it manifested on cave walls or in broken artifacts, but it has no natural history. Similarly, it is difficult to nail down when, exactly, a human being’s conscious experience begins. Research sheds broken shafts of light on this question. But, as one team that studied the emergence of infant experience put it last year, progress is difficult “because of uncertainty about how best to study consciousness in the absence of the capacity for verbal report or intentional behavior.”¹

Consciousness is called the “hard problem” of the philosophy of mind for good reason. There is no known physiological “seat of consciousness” in the brain. Thus, philosophers who wish to do so can make a living out of denying its existence. And yet , our own consciousness is the one thing of which we are most sure!

We can have modest confidence in tackling some questions though, including some controversial ones.

Early Behaviors & Sensory Experience

The prenatal brain grows very rapidly, so the child in the womb mostly sleeps. Allen Institute neuroscientist Christof Koch estimates that in late gestation the fetus is in one of two sleep states 95 percent of the time, separated by brief transitions. Some experi­ences and behaviors predate birth, though. For example, thumb sucking develops the muscles needed for ingesting milk, and side preferences in arm movements observed as early as ten weeks’ gestation, including thumb sucking, appear to predict left- or right-handedness in most humans.

Taste buds develop anatomically at eight weeks’ gestation, and flavors from the mother’s food that seep into amniotic fluid have been associated with fetal facial movements. Some researchers think these experiences may influence our tastes in food, with consequences for diet, later in life. Prenatal hearing helps shape the brain, including “specialization for the native language.  . . . Fetuses already learn from this prenatal experience: Newborns prefer their mother’s voice over other female voices and show a preference for the language their mother spoke during pregnancy over other languages.”² The child hears the rhythm of speech, not individual words, through the amniotic fluid. That rhythm likely contributes to the phenomenally rapid speech acquisition among toddlers. Clearly, the child is being prepared from the beginning to be a member of a human community.

Abortion, Fetal Pain & the Politics of Consciousness

Then we come to the difficult question of pain —in this context, difficult because so many children are aborted. Neurosurgeon Michael Egnor points to the unpleasant fact that the thalamus, identified from eight weeks’ gestation, creates a sensation of pain, which is then modulated by the cortex. Less-mature humans can experience pain more intensely than adults because their modulation skills are undeveloped. “Babies obviously experience pain, and indeed appear to experience it more intensely than do adults,” Egnor writes. “This extreme sensitivity to pain in young fetuses and babies is well-recognized in medical science.” Elsewhere he comments,

I have cared for hundreds of premature infants, and it is very clear that these very young children experience pain intensely. An innocuous needlestick in the heel to draw a small amount of blood would ordinarily not be particularly painful for an adult. But a tiny infant will scream at such discomfort.

Abortion advocates will sometimes admit the suffering.³ It’s the humanity and worth of the tiny sufferer they deny.

How deeply entrenched is their view? It helped fuel a recent, discipline-shaking uproar in consciousness studies. Twenty-five years ago, Koch made a bet with leading philosopher of consciousness David Chalmers: A case of fine wine says that a brain consciousness circuit will be found by 2023. It wasn’t. The journal Nature reported on the outcome of the bet in June 2023, tallying the score at: Chalmers 1, Koch 0. At first, it was all rather convivial.

By September, however, the mood had changed. One hundred twenty-four neuroscientists and philosophers of mind slammed Koch’s leading theory of consciousness (integrated information theory, which posits that the consciousness of a being is related to its interconnected information) as “pseudoscience.”⁴ Most of the technical details of the theory are not germane to the uproar that followed, but we might reasonably ask, was it denunciation for losing the bet? Maybe, but there’s more.

Koch is a panpsychist. He believes that “Simple things like maybe a fly or Protozoa have very, very, very simple minds associated with them.”⁵ But that raises the possibility that prenatal humans, too, have some sort of mind. According to the “Cancel Koch!” letter published by the 124 signatories, their worry is that, along with other life forms, “human fetuses at very early stages of development . . . are likely conscious according to the theory.”⁶ Quelle horreur.

Science writer John Horgan picked up on that point immediately:

Integrated information theory implies that consciousness is ubiquitous. If the theory is widely accepted . . . it could influence our treatment of smart machines, comatose patients, research animals, stem cells and fetuses.

After all, the more sentience we impute to something —like a week-old human embryo —the more rights we should grant it. Yes, we’re talking about abortion. With “so much at stake,” the letter-signers state, “it is essential to provide a fair and truthful perspective on the status of [integrated information] theory. As researchers, we have a duty to protect the public from scientific misinformation.” Science journalists have the same duty.⁷

Now Horgan may not have intended this. But it sounds as though he is saying that protecting the public from scientific misinformation includes denouncing the leading theory of consciousness —if it points in the direction of unborn humans possessing sentience.

In a world where evolutionary psychologist David Barash argues that worms feel pain⁸ and other researchers ask whether squid and crabs have emotions,⁹ unborn children are the one single life form at one single stage that must for sure lack consciousness and sentience.Whatever approach to science that is, it isn’t an inference to the best explanation.

Notes
1. Tim Bayne, et al., “Consciousness in the cradle: on the emergence of infant experience,” Trends in Cognitive Sciences, 27(12) (October 12, 2023).
2. Mariani Benedetta, et al, “Prenatal experience with language shapes the brain,” Science Advances, 9(47) (November 22, 2023).
3. Stuart WG Derbyshire, John C. Bockmann, “Reconsidering fetal pain,” Journal of Medical Ethics (January 2020).
4. Mariana Lenharo, “Consciousness theory slammed as ‘pseudoscience’ —sparking uproar,” Nature (20 September 2023).
5. Kmele Foster, “Consciousness: Not Just A Problem for Philosophers,” Big Think (December 5, 2023).
6. Stephen Fleming, et al, “The Integrated Information Theory of Consciousness as Pseudoscience,” PsyArXiv Preprints (September 15, 2023).
7. John Horgan, “The Brouhaha Over Consciousness and ‘Pseudoscience’,” (September 23, 2023).
8. David P. Barash, “Even Worms Feel Pain,” Nautilus (March 2, 2022).
9. York University, “Do Octopuses, Squid and Crabs Have Emotions?” News@York (March 24, 2022).