Magnetoencephalographic signatures of conscious processing before birth.
Julia Moser, Franziska Schleger, Magdalene Weiss, Katrin Sippel, Lorenzo Semeia, Hubert Preissl
Developmental Cognitive Neuroscience June 1, 2021 DOI: 10.1016/j.dcn.2021.100964 (opens in new tab) via PubMed
Summary
AI-generated from the abstractFetuses in the last trimester of pregnancy show signs of hierarchical rule learning, a cognitive ability linked to conscious processing. Using fetal magnetoencephalography on 56 healthy fetuses between gestational weeks 25 and 40, an auditory oddball paradigm with first- and second-order regularities was presented. Brain responses to standard versus deviant tones indicated formation of a memory trace for the second-order regularity, an ability that develops with physiological brain maturation and was reliably present only in fetuses older than week 35. Autonomic nervous system activity, replicating findings in newborns, showed the importance of activity state for cognitive processes. These results support the assumption that fetuses in the last weeks of gestation can consciously process stimuli from outside the womb.
Study at a glance
| Characteristics | Observational cohort Peer reviewed |
|---|---|
| Sample size | 56 |
| Population | Healthy fetuses between gestational week 25 and 40 |
| Keywords | Brain maturation Cognitive development Consciousness Fetal meg Hierarchical rule learning |
| Key finding | Fetuses older than 35 weeks of gestation show reliable hierarchical rule learning, supporting the possibility of fetal conscious processing. |
Abstract
The concept of fetal consciousness is a widely discussed topic. In this study, we applied a hierarchical rule learning paradigm to investigate the possibility of fetal conscious processing during the last trimester of pregnancy. We used fetal magnetoencephalography, to assess fetal brain activity in 56 healthy fetuses between gestational week 25 and 40, during an auditory oddball paradigm containing first- and second-order regularities. The comparison of fetal brain responses towards standard and deviant tones revealed that the investigated fetuses show signs of hierarchical rule learning, and thus the formation of a memory trace for the second-order regularity. This ability develops over the course of the last trimester of gestation, in accordance with processes in physiological brain development and was only reliably present in fetuses older than week 35 of gestation. Analysis of fetal autonomic nervous system activity replicates findings in newborns, showing importance of activity state for cognitive processes. On the whole, our results support the assumption that fetuses in the last weeks of gestation are capable of consciously processing stimuli that reach them from outside the womb.