Pre- and perinatal brain development and enculturation: a biogenetic structural approach by



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NOTES


*Address inquiries to the author, Department of Sociology and Anthropology, Carleton University, Ottawa, Ontario, Canada K1S 5B6.

1This paper was presented at the annual meeting, American Anthropological Association, Washington, D.C., November, 1989. The author wishes to thank Judi Young for her editorial suggestions.

2We use the term "cognitive" in the broadest sense to mean any neurophysiological operation involved in knowing. This contrasts with the more narrow sense of computational or propositional modes of knowing as used by some cognitive scientists.

3Biogenetic structuralism is an interdisciplinary approach to the study of cross-culturally universal regularities of behavior, symbolism, consciousness and cognition that combines evolutionary biology and the neurosciences with phenomenology and the social sciences (Laughlin and d'Aquili 1974, d'Aquili, Laughlin and McManus 1979, Laughlin and Brady 1978, Rubinstein, Laughlin and McManus 1984, Laughlin, McManus and d'Aquili 1990).

4We are aware of the difficulties in defining the concept of "consciousness" (see Laughlin, McManus and d'Aquili 1990:76-82, also Kagan 1989 on this issue). The term is highly subjective, and the problem is to relate subjective reports of the experience of consciousness to objective knowledge about the structure of the brain. We use the concept of consciousness in a phenomenological sense. Consciousness means that there is a subject and that subject is aware of experience (see Dilthey 1976). Biogenetic structuralism holds that consciousness is subserved by a neurognostically structured "conscious network" of the brain.

5It used to be thought that these neural structures did not begin to function until their axons has been coated with myelin (a fatty sheath that is wrapped around some axons as a kind of insulation; e.g., Langworthy 1933). It is now known that myelin has the effect of modifying the speed of transmission of signals in cells that are already functioning (Larroche 1966: 273, Bekoff and Fox 1972, Yakovlev and Lecour 1967). Myelinization usually proceeds from the most archaic parts of the nervous system through the most recent, thus reflecting in ontogenesis the stages of evolution of the nervous system in phylogenesis (Larroche 1966).

6In many of our writings we call the substrate of consciousness (at whatever stage of development) an individual's conscious network and the world of lived experience constituted by the conscious network an individual's cognized environment (Laughlin, McManus and d'Aquili 1990). We have argued in numerous writings that conscious network and the cognized environment develop in interaction between the system of initial, genetically predisposed neurognostic models and the operational environment.

7I presume (in the company of Ashby 1960, Piaget 1971, Varela 1979, Brazelton and Als 1979, Brazelton and Yogman 1986, and Purves 1988) that the human fetus and infant is an active, autonomous, adapting, self-regulating, and self-constructing organism.

8A bias that has long hampered our understanding of pre- and perinatal consciousness and cognitive competence is that neural structures must in some sense be complete in their development before they are able to function. This view has increasingly come into question (see Gottlieb 1976b, Klosovskii 1963, Klopf 1982: 6) as theorists realize that nerve cells are not sort of organic microchips that remain static until they are "wired-up" to networks, but rather are living, functioning organisms in their own right. A more realistic view is that the body of a pre- and perinatal child is comprised of hundreds of trillions of cells of many thousands of types and of every conceivable description. The child is in fact a community of cells; a community of discrete organisms that are, themselves, made up of various parts like membranes, mitochondria, organelles, and nuclei (Varela 1979, Laughlin, McManus and d'Aquili 1990). The nervous system is an organ or sub-community within the greater community of cells. Each of the nervous system's 1012 neurons is a goal seeking unit that becomes more and more involved in a hierarchy of nested networks (Powers 1973, Klopf 1982: 13, Varela 1979, Glassman and Wimsatt 1984). The nervous system is the organ of the body that specializes in the purposeful regulation of vital functions, tracking events in the world of phenomenal experience that it, itself, constitutes, and organizes the myriad systems of the body into adaptively appropriate entrainments. And most importantly for our current purposes, the nervous system constructs a cognized environment within the context of which discrete events are cognitively evaluated (Granit 1977). And the immature nervous system during the early months of prenatal life "comprises a roughed-in structure whose levels and subsystems are poised for coding of certain categories. The subsystems are neither wholly flexible nor wholly predestined players in a ballistic ontogenesis" (Glassman and Wimsatt (1984). The vast majority of cells comprising neural models are those that communicate only with other cells within close proximity ("local circuits;" see Uttley 1966, Rakic 1976).

9Although, as Aslin (in Mehler and Fox 1985: 157) notes, it is difficult to establish "the relative contribution of genetic and experiential factors to the ontogeny of individual members" of our species, it seems probable that consciousness and learning begin at some point in early gestation and develop rapidly and in tandem with the genetic factors controlling ontogenesis throughout the prenatal and perinatal period (Gottlieb 1983: 5). Given the confines of our present knowledge, it is pointless to try to establish the exact stage at which the prenatal child is conscious, for different investigators have different conceptions of what constitutes "consciousness" and thus much intersubjective disagreement.


10It is interesting that neurogenesis is prolonged in the hippocampus and continues well after birth. This may be related to delayed development of the behavioral and memory functions of that area (Altman 1970, Altman, Brunner and Bayer 1973).

11But see Myers (1987) on the question of whether there exists a sensitive period during the puerperium during which mother-infant bonding occurs.

12It is, of course, very difficult to know what a sleeping baby is experiencing. We know that the baby's brain is very active during sleep, and that it is in REM sleep most of the time. My suspicion has been for a long time that the younger the child (fetus/newborn), the more archetypal the dream symbolism is likely to be, and the older the child (from later infancy on), the more memories of events in the external operational environment will influence dream symbolism. There exist very little data on the matter so far.
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