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This article is from the In-Depth Report The Mother-Baby Bond
See Inside September / October 2009

When Does Consciousness Arise in Human Babies?

Does sentience appear in the womb, at birth or during early childhood?

Dreamless Sleep?
One complication ensues. When people awaken during REM sleep, they often report vivid dreams with extensive narratives. Although consciousness during dreams is not the same as during wakefulness—most noticeably insight and self-reflection are absent—dreams are consciously experienced and felt. So does the fetus dream when in REM sleep? This is
not known. But what would it dream of?

After birth, dream content is informed by recent and more remote memories. Longitudinal studies of dreaming in children by retired American psychologist David Foulkes suggest that dreaming is a gradual cognitive development that is tightly linked to the capacity to imagine things visually and to visuospatial skills. Thus, preschoolers’ dreams are often static and plain, with no characters that move or act, hardly any feelings and no memories. What would dreaming be like for an organism that spends its time suspended in a sort of isolation tank, with no memories, and no way to imagine anything at all? I wager that the fetus experiences nothing in utero; that it feels the way we do when we are in a deep, dreamless sleep.

The dramatic events attending delivery by natural (vaginal) means cause the brain to abruptly wake up, however. The fetus is forced from its paradisic existence in the protected, aqueous and warm womb into a hostile, aerial and cold world that assaults its senses with utterly foreign sounds, smells and sights, a highly stressful event.

As Hugo Lagercrantz, a pediatrician at the Karolinska Institute in Stockholm, discovered two decades ago, a massive surge of norepinephrine—more powerful than during any skydive or exposed climb the fetus may undertake in its adult life—as well as the release from anesthesia and sedation that occurs when the fetus disconnects from the maternal placenta, arouses the baby so that it can deal with its new circumstances. It draws its first breath, wakes up and begins to experience life.

Note: This article was originally printed with the title, "When Does Consciousness Arise?"

This article was originally published with the title "Consciousness Redux: When Does Consciousness Arise?."

(Further Reading)

  • The “Stress” of Being Born. Hugo Lagercrantz and Theodore A. Slotkin in Scientific American, Vol. 254, No. 4, pages 100–107 (92–102); April 1986.
  • The Importance of “Awareness” for Understanding Fetal Pain. David J. Mellor, Tamara J. Diesch, Alistair J. Gunn and Laura Bennet in Brain Research Reviews, Vol. 49, No. 3, pages 455–471; November 2005.
  • The Emergence of Human Consciousness: From Fetal to Neonatal Life. Hugo Lagercrantz and Jean-Pierre Changeux in Pediatric Research, Vol. 65, No. 3, pages 255–260; March 2009.
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