The Neuroanthropological Fabric of Spirit

John A. Teske, Ph.D.

Elizabethtown College

Elizabethtown, PA 17022 U.S.A.

It is the present contention that our spirituality is a product of the very processes of human evolution which make the social construction of human culture, human meaning, and individual psychology possible, and even necessary. Evolutionarily adaptive characteristics of human neuropsychology require that we live in a social world, making the construction of personhood near-inevitable, and making a spiritual life possible. Our species is likely to have been evolutionarily advantaged by the extended childhoods and complex social interdependencies that the coevolution of brain and language required (Deacon 1992). This included the capacity to function in an "as if" manner that intentional representations of the world make possible, and which allow us to operate within socially constituted understandings of the world, our fellows, and ourselves. Such understandings are also grounded in prelinguistic and subdoxastic capacities to coordinate our behavior and our emotional lives with each other. The human nervous system is likely to have evolved in ways which require social interdependency, not only for the survival of groups but for the canalization of individual nervous systems and the genesis of individual psychologies. We human persons, over and above but inclusive of our neural functioning, are constituted by our placement within larger social wholes, no less real for being symbolically generated, playing a potential emergent role as higher-order units in evolutionary processes. Indeed, "group selection" (Wilson & Sober 1994) may be the level at which archaic moral orders evolved to overcome the natural problems produced by genetic competition amongst members of a group (D. Campbell 1991). As such, neuropsychological mechanisms are involved in both constructing and reaching beyond our individuality, processes of social construction which presuppose membership in a more extended hierarchy of social units, including relationships, families, and wider communities.

When we understand that the self, our subjectivity, our internal life, is a socially constructed logical space, we have a handle on the constitution of individual spiritual lives. Jaynes (1976) and others (cf. Hermans, Kempen, & van Loon 1992) argue that our very consciousness of self is constituted and organized metaphorically as a space. Metaphor is a central concept, given our ability to direct our lives toward conceptual objects, to live, as it were, metaphorically, "as if," in the virtual reality of symbolic systems. But this is also what allows us to build a meaningful communal life, and step beyond our own egos. Nevertheless, evolutionarily and historically contingent though they may be, the forms that constitute our selves are interiorized in a particular way, nested within the evolutionary biology of socially interdependent nervous systems, deeply interwoven with the neuroanthropological fabric. Spiritual life does not escape the sociohistorical and evolutionarily embodied contingencies by which it is constituted. The central focus of the present paper is to draw out some of the fibers of the neuroanthropological fabric from which our psychology, and our spiritual experience, is woven. The passions of faith, and "spiritual" questions about boundaries between self and other, alienation, will, surrender, communion, and even the experience of grace may ultimately be understood more fully as embodied phenomena by attention to these fabrics.

The present work is part of a larger attempt to map out the constitution, and the embodiment of our spirituality, in terms of what we know about human minds and brains from contemporary cognitive and neurosciences. This is a project which is necessary for any kind of theological or religious system that is coherent with science, the only chance for its viability of in a world dominated by a scientific episteme. Two years ago, in this forum (Teske 1996a), I argued that both our self-transcendence and the self-limitations that require it are made possible by our neuropsychology. I also argued that our individual integrity depended upon a boundary between internal and external life which was as much a product of historical social life as of evolutionary biology. Our very internality, at its deepest roots, may not be the individuated consciousness of an ego separate from others, but constituted by the sociohistorical nexus of our individual development. Nevertheless, the social nexus of our development is itself embedded within the biological unfolding our species. It is to the evolutionary and developmental background of our psychological and spiritual emergence, as understood through the glass of contemporary sciences of mind, that I turn here.

A further set of arguments has made it all the more important to understand the social interdependencies which, evolutionarily and developmentally, root the ontogenesis of human mental and spiritual life (Teske, 1996b). While neuropsychology is necessary for spirituality, the very characteristics which make spirituality possible also provide limits which individuals cannot alone transcend. Reflection, consciousness, and self-knowledge require a neuropsychology sufficient for symbolically representing a world and a self within it. But representations are always selective, abstract, constructed, and partitioned, and therefore limited by bias and incompleteness, separation from the world, fabrication and self-deception, and the possibility of fragmentation and decay. The evidence from research on hemispheric specialization, brain dysfunction, and normal memory suggests that the unity and integrity of self and mind is a contingent achievement. Our sense of unity and integrity may be subdoxastic and subcortical, perhaps rooted in the limbic substrate of our emotional lives. Or it may depend upon the integrity of relation, the suggestion that the self may be incomplete, and insufficient for the work of integration, without a place in some larger system or community. The latter suggestion points to the interesting possibility that the healing of individual separation and fragmentation may be bound for failure without attention to the separation, fragmentation and destruction of the communities that constitute and maintain our individuality. Nevertheless, both emotional and relational life point to a likely reason why neuroscience cannot provide a complete account of human nature or human spirituality (Jones 1992). This is because many of the important characteristics of both mind and spirit are not only emergent properties of an individual's central nervous system (Sperry 1991), but may be social emergents, i.e. properties of a number of individuals (and a number of individual nervous systems) in interaction. It is the present contention that not only is this so, but that the evolutionary and developmental evidence will show us why and how our social interdependencies, our membership in larger human groups, are both necessary for and constitutive of much of what we believe to be characteristic of the mental and spiritual life of human beings. We will begin by addressing overarching issues of neuroplasticity and cognitive evolution, and then will sample more specific developmental changes, both evolutionary and ontogenetic, which may support the social constitution of mind and spirit.

One of the central principles necessary for understanding human development is that of our extensive neurobehavioral plasticity. The nature/nurture controversy has long given way to interactionist views. The last few decades have uncovered a great deal about how biological processes interact with the external world during growth and development, showing measurable effects on the anatomy, physiology, and chemistry of the nervous system (Blonder 1991). While genetics do set some constraints, there is plasticity at every level of development (Nowakowski 1987). Cells and their interconnections proliferate, migrate, differentiate, and are pruned directly by experience with the external world, affecting synaptic connections, dendritic growth, neurotransmitter synthesis and even vascularization.

We are left with a brain that is constantly being shaped, in structure and function, by its history of developmental interactions with the outside environment. David Hubel and Thorstein Wiesel, awarded the Nobel Prize in 1981, found that depriving cats or monkeys of certain visual stimuli (e.g. vertical lines) resulted in the loss of cells in the cortex for detecting them. Rats reared in enriched environments have larger neurons, greater dendritic spread, and greater enzyme production (Rosenzweig, Bennett, and Diamond 1972). Greenough (1986, Greenough, Black, and Wallace 1987) has provided evidence for remarkable plasticity even in the cerebellum for synaptic growth with skill development. He also provides evidence for both "experience-expectant" overproductions of synaptic connections for species-ubiquitous environmental information (experience itself selecting which connections remain), and for "experience-dependent" novel synaptic connections formed in response to idiosyncratic individual experience. There is also a growing body of evidence for neurobehavioral plasticity in human beings that extends across the lifespan: the dependence of left-hemisphere, language-area maturation on appropriate stimulation pre-puberty; the quantitative increases in left-hemisphere dominance for language produced by literacy; the elimination, during adolescence and young adulthood of excess synapses in the principal sulcus, which appears to be necessary for fully mature delayed-response functioning; and the extensive dendritic growth in the learning and memory-crucial parahippocampal gyrus among normal elderly people (cf. Blonder 1991, Goldman-Rakic 1987).

Given the neurobehavioral plasticity of even the lowliest of mammalian species, it is clear that the cognitive abilities required for spirituality are not just genetically constrained, but epigenetically constructed and dependent on extensive environmental experience for their emergence. It is also clear that the developmental environment of human beings and their hominid ancestors is a socially mediated environment, an environment increasingly influenced by human activity, to the point of becoming a virtual reality of human artifacts. While this suggests a heavy influence of human culture and learned behavior on the ontogenesis of human mental and spiritual life, we must be cautioned that, in the face of evidence for a number of human cultural and linguistic universals (cf. Brown 1991), cultural differences may themselves be relatively superficial. This suggests that, despite the importance of cultural and social supports in the ontogenesis of individual psychology, we had best acknowledge that it has deeper evolutionary roots. Nevertheless, Lewontin (1990) warns us about the limitations of the evidence for the biological evolution of human cognition, and Gould (1992) even suggests that many of our emergent cognitive skills (including, for example, literacy) may be maintained at levels of evolution higher than genes or organisms (e.g. populations, species), and therefore provide us no more than bookkeeping data at biological levels.

It should thus come as no surprise that there may be less than a one percent difference between the DNA of chimps and humans, suggesting that any determination of cognitive abilities not shared between us are likely to be epigenetic or even developmental (King and Wilson 1975). Evolutionary changes in cognitive abilities, despite their cultural amplification, may not involve radical changes at the neural level. "If psychological evolution, like morphological evolution, can be meaningfully thought of as innovations in ontogeny, then comparative psychologists should have no trouble accepting as a possibility that a major evolutionary change occurred quite recently in primate history" (Povinelli 1993, 506). Even human language capacities are likely to be polygenetic, shared with other developmental domains, tied to epigenetic and probabilistic maturational events and, given the multifunctional and individual variability of human brains, not strictly universal in functional organization (Mueller 1996). Small differences in DNA must play a role in a number of differences between humans and other primates, including cortical investment in speech-related musculature, the double voicebox in the larynx, upright stance and bipedalism, female pelvic changes, the underdevelopment of human babies (requiring greater parental and social investment), and, perhaps most importantly for our purposes here, our brain size, particularly the disproportionate amounts of prefrontal cortex, hippocampus, and cerebellum (responsible for complex motor sequencing, long-term memory, and complex motor coordination respectively). Epigenetic plasticity alone could grant a huge role for culture as a storage device for processes replicative of human cognitive function.

The other general principle needed for understanding the ontogenesis of human cognition is the hypertrophy of prefrontal cortex (Deacon 1992). This is the major neurological change behind our being, relative even to other primates, linguistic or combinatorial savants, creatures that can live in symbolic virtual worlds, can construct meaningful narratives, can imagine their own origins and ends, and can conceive of God. Prefrontal hypertrophy, in combination with an overall neurobehavioral plasticity (and the concomitant roles of epigenesis and development in generating human cognition) also guarantees the colonization of human neuropsychology by the prefrontal functions of attentional control, planning, and complex motor sequencing, and so constitutes the particular character of higher cognitive functioning.

Terrence Deacon (1992) makes this case clearly. He accounts for the absence of even simple language-like symbolic systems in other primates by drawing our attention to the most robust and divergent neuroanatomical feature of human brains relative to other primate species. This is the enlargement of prefrontal cortex and the expansion of projection fields which contribute to the attentional-mnemonic supports critical to symbolic and associative learning. This prefrontal hypertrophy guarantees a predisposition to employ symbolic learning, and facilitates the computational learning behind the evolution of human cognition, consciousness, and culture. This is the brain structure supporting the special demands of language which are the most modified by environment-related developmental changes, a system so overbuilt and failsafe that even retarded and brain-damaged human beings are still often capable of symbolization. The primary evidence has to do with the fact that while other brain structures in human beings have grown in an unchanged ratio to body size and other brain structures, the ratio of neocortex to other structures is larger. This difference is produced by the action of homeobox genes producing disproportionate embryogenic growth in the dorsal half of the brain (Deacon 1992). The information for building these structures is not itself in the genes but in circuits and information from the environment, sculpted by the environment in a kind of neural Darwinism in which circuits are grown in a process of competition for space. The neocortical hypertrophy produces a kind of bias in the competition for space in which the structures of the brain most controlled by input from the outside world remain the same relative size but smaller than the rest of the neocortex. The prefrontal areas therefore inherit the largest share in competition for space, and increasingly come to dominate connections to other parts of the brain, especially those contiguous areas controlling vocalization. These areas are distinct from the subcortically mediated systems controlling laughing, crying, and other vocalization more resembling primate call systems. Novel functions are thereby produced by the disproportionate frontal impact. The evidence from electrical stimulation, cerebral blood flow, and brain damage suggests that it is frontal cortex function that is behind our abilities to shift categorization criteria, generate word lists, do syntactic analysis, and generate the novel patterns that enable insight learning.

Deacon (1992) argues further that emergent frontal cortex functions are what give us entree to a symbolic "virtual reality." They allow us to make the step from indexical mappings of sign-event co-occurrences to symbolic re-presentations, in which similar things are connected not just by indexes but by other similarities. The result is that no representations are simple, and symbolic reference is always systemic. Once this systematicity is present, new symbolic associations can always be learned by restructuring, by retrospectively reorganizing previous connections in respect to one another. This gives us a capacity for generating an abstract virtual world only indirectly connected to the concrete present, for representing possible and impossible futures, and for having access to an illimitable symbolic world. Moreover, once this capacity emerges, with its ontogenetic social and cultural supports, it becomes necessary for human reproductive success, as an individual human being lacking this capacity becomes locked out of the human social world. We become overdependent on the symbolic transfer of learning, and enter a way of life driven by a compulsion to symbolize. We are also granted the capacity for symbolic empathy, via cortico-limbic ties allowing us to match arousal states to representatons, to make believe, and to imagine the experience of fellow beings, from the sublime to previously unimaginable horrors. With the symbolic capacities made possible by prefrontal hypertrophy, human sociability is no longer based solely on genetic contributions, nor on animal communication and meaning, but on the symbolic transfer of sociohistorical learning, and the colonization of human psychology by higher cognitive function. We can now examine more specific neurological structures and functions in terms of the evolution and ontogenesis of the human capacity (even the necessity) to live in a socially constructed, symbolic virtual reality.

Fairly primitive brain structures mediate arousal, which influences attentional selection, sometimes almost totally, but in ways mediated both by circumstances and past experience. Arousal is likely to be a prerequisite for attention, involving stimulation from the reticular formation, itself a distributed network which also includes cortical connections. Attention may also be controlled by rhythmic aspects of arousal, involving heart rate and muscular tension changes. However, not only is it clear that we need brain stem (and limbic) interactions to understand the cognition which is built upon them, but, given the extensive epigenetic and ontogenetic shaping of this relationship, we must also understand its embedding within a complex system of developmentally supportive social interchanges. The role of symbiotic caregiver-child interactions in the scaffolding of the child's ability to self-moderate arousal levels begins a process of social internalization almost at birth, and roots an extensive system of object-relations (e.g. Mahler, Kohut). The social scaffolding of attention is also a prerequisite of linguistic communication (Sherwood and Bruner 1975).

The social scaffolding which structures the regulation of arousal and attentional mechanisms, and which contextualizes our experiences of our bodies and their boundaries, emerges in and is mediated by the basic mammalian attachments that form the foundation of our emotional lives. Even in rats, the period of dependency required by the rearing of infants makes early social attachment adaptive and survival-relevant. The mother's role as regulator of physiologial and behavioral systems in the infant is most evident in the synchrony and reciprocity of nursing, and responses of infants to separation may be a kind of withdrawal or release phenomenon (Hofer 1987). Given a much lengthier period of dependency in human childrearing, attachment patterns and developmental experience within familial contexts are likely to be even more deeply determinative of the social and emotional patterning of adult lives. Tomkins (1979) and others provide accounts of how recognizably human affect complexes and fuller emotional scenarios are built out of biologically primary motivators over decades of biographical development. Our evolutionarily structured neuropsychology may require our attunement to, and functioning within, a hierarchically structured, socially interdependent world which requires, in turn, the development of fairly sophisticated cognitive and emotional elaborations of primary motivators. While such motivators may be constrained by the evolutionary contingencies embodied in our genetics, they are hardly determinative, but provide an envelope for understanding the role that cultural and biographical variations might play in the construction of different emotional tones, and different kinds of self/not-self and self/other emotional boundaries. James Ashbrook (1994) has characterized the early experience of separation from a loved object, and the emotional need to fill this separation with transitional objects and symbols (cf. Stern 1985, Winnicott 1965), as central to a spiritual "cry for the other," and as motivating the meaning-making which roots consciousness, creativity, and faith.

Human emotional life, particularly as it is mediated by reciprocal connections between the limbic system and the neocortex, has been viewed as the locus of religious sentiment by a number of thinkers. MacLean (1988), as well as Ashbrook (1994), focus on early family dynamics, including maternal nursing, separation cries, and sibling play. Robin Fox (1986) also implicates early learning, including the separation and stranger anxieties which appear between 6-15 months, concomitant with the myelinization of limbic circuit fibers. Nevertheless, Fox also offers a more detailed analysis of limbic-cortical connections, suggesting that it is a wired-in mechanism for the disruption of social categories that is behind both the alerting responses to minor cognitive mismatches, and the passionate upsets of horror, disgust, and fear in response to more serious violations of social expectations. Areas of the brain that are involved in emotion are also involved in memory; it is the emotional charge of an event that most directly determines how well it is remembered. Fox reminds us that there are connections through the hippocampus which are vital to encoding new memories. The hippocampus itself, lying just beneath the frontal cortex, receives no direct sensory information, but only abstracted and cortically processed information passed via the cingulate gyrus to the hippocampus, and eventually back to the cortex. Selecting emotionally significant memories for long-term retention is necessary to avoid a kind of combinatorial explosion of memory in higher mammals. By a limbic-frontal linking of visual images and complex associations to emotionally significant information, especially that tied to initiation, trauma, drama, ritual, and fear (precisely those experiences most strongly tied to learning and relearning of central social categories), these memories are the ones most likely to be consolidated over a period of years, as the plethora of more shallow memories are washed away in the accumulation of experience.

Este Armstrong (1991) provides allometric evidence of some limbic differences between human and primate brains, and supports the importance of attentional and memorial endowment of symbols with emotional significance and meaning. The amygdala, mediating negation and anxious aggression, septal areas, mediating positive feeling and sexual response, and the hippocampus, with its role in consolidating short-term, explicit memory (but not skill development) into long-term storage, are all larger than they are in primate brains, but are not scaled differently, suggesting that these structures do not serve radically new functions. Limbic structures that do scale differently include relatively smaller olfactory structures, and a relatively larger anterior thalamus. This is part of the Papez circuit, which brings emotional information into the cortex for further elaboration and conscious access.

Papez circuit structures like the hippocampus and cingulate gyrus (which can focus attention either on parietal information about extrapersonal space, or on prefrontal information related to the "internal space" of subjectivity) are well placed for activation by association cortex, which plays the role of input to the limbic system, otherwise largely divorced from direct sensory input. As part of the Papez circuit, anterior thalamic structures may be critical for the brain's ability to remember cultural rules and events, and play a role in the emotional prioritizing, and approach/avoidance valencing of symbolic representations of events. Alternatively, cortical feedback, particularly inhibitory influences, are likely to be important for social cooperation, as human beings can approach and engage in joint social activities without direct expression of hostility or sexuality. Nevertheless, while there do appear to be some important, if subtle changes in limbic structures, and in the relationship between cortex and limbic system, much appears to be driven, in evolutionary if not motivational terms, by more radical changes in the cortex. Moreover, extensive cortical neuroplasticity makes possible, and may even require, cultural and institutional supports in order to produce cognitive development.

Some of the important prerequisites to human-level cognitive and cultural capacities, particularly to having subjective interior lives and to attributing the same to our fellows, are already present in our nearest primate relatives. Cheney and Seyfarth have provided evidence in chimpanzees for short-term planning, transitive and analogical reasoning, deliberate deception (with Smuts 1986), and even the attribution of mental states (1990). Gordon Gallup (1970) provided an early demonstration of the ability of chimps to recognize themselves in a mirror, an ability which emerges in human children between 18-24 months, and he has more recently reviewed evidence for the existence of this ability in 20 other species of apes, but in no monkeys. Premack and Woodruff (1978) have argued that self-recognition is an empirical marker for having a "theory of mind," and Gallup (1982) has presented a model in which self-recognition is taken to index both a capacity to introspect on mental experiences and the means to infer such experiences in other organisms. Povinelli (1993) extends Gallup's work, arguing that children lacking self-recognition fail to attribute mental states, and are incapable of introspection-based social strategies. He also points out that the self-conscious emotions emerge at about the same time as self-recognition. It is clear that self-recognition is a necessary, if not sufficient index for a number of higher cognitive abilities, and Povinelli provides experimental demonstrations of the attribution of mental states and of false beliefs in both chimps and older children which are lacking in monkeys and younger children. It is clear that socially-relevant cognitive abilities like reflective consciousness, attributions of intent, perspective-taking, role reversal, attention to knowledge over behavior, and the attributions of false belief necessary both for deception and its detection require a number of years for their development in human children, but may be available to many adult apes. Nevertheless, it is to the emergence of specifically human cognitive capacities, and their needs for extensive linguistic and cultural support, that we now turn.

Merlin Donald (1991, 1993) argues that any comprehensive theory of human cognitive evolution must bridge the huge gap between the animal kingdom and the uniquely human invention of symbols. He bridges this gap by suggesting the evolutionary emergence of an ability he calls "autocuing," the self-initiated recall of specific items of memory independent of the immediate environment. This ability would provide our hominid ancestors with their first representational ability to "think about" things unrelated to the immediately present environment, and with new voluntary retrieval paths to their already present knowledge base. Donald's suggestion is not only consistent with a prefrontal hypertrophy allowing different access routes to limbically mediated memory, but also is a separate and preliminary step to the evolution of language. There are both anatomic and cultural signs of a major evolutionary landmark with the emergence of homo erectus (1.5-0.3 million years ago), the cultural achievements in particular (e.g. sophisticated stone tools, long-distance hunting, seasonal adaptations) requiring memory improvements. Nevertheless, these changes are not likely to have been accompanied by language, the anatomic and cultural signs for which do not appear for another million years.

Donald (1993) suggests that prelinguistic autocuing allows nonverbal representational skills, the existence of which is also consistent with the autonomy of nonverbal forms of human intelligence and which, accompanied by cortically mediated improvements in motor control, would allow the development of mimetic skills advanced enough to support toolmaking, skill refinement, and a flexible social organization superior to that of apes. Mimetic skills, based on a memory system that, in an extended kinematic imagination, enables the voluntary and systematic rehearsal and refinement of movements (seen frequently even in human children, but rarely in apes), allow for an implementable self-image, have supramodal characteristics like rhythm (also absent in apes), and make purposive, alterable sequencing possible. Like the sophisticated mimetic and expressive abilities of illiterate deaf-mutes, the culture of homo erectus may have been the complex mimetic one in which we can still see our symbolic and linguistic culture to be embedded. This includes crafts, games, social rituals, expressive scenarios, and even many athletic skills, nonverbal skills unaffected by even profound aphasias.

According to Donald (1991, 1993), it is with emergence of the modern vocal tract and its motor control that we see, with the emergence of archaic homo sapiens between 500-100 thousand years ago, evidence for real language. Donald suggests that this second evolutionary landmark corresponds to the evolution of "lexical invention," the capacity to invent and retrieve thousands of words and the rules for their combination (perhaps in a second phase of "grammatical invention"), allowing the construction of narrative commentaries. Portable, efficient, true symbols can not only disambiguate mimetic messages (or contrast with them to produce more complex, layered meanings) but provide a second form of retrievable knowledge, and a second-order modeling. The shift from re-enacting to storytelling also takes the teller outside the story, and allows freer examination, reassembling, and sharing of components. This makes possible the incredible speed of language differentiation, the production of collective, standardized narratives in mythology and religion, and provides a narrative frame for the governance of pre-existing mimetic institutions. Indeed, while we may form and maintain our social constitution largely by routinization, by daily habits, and by group rituals, its meaning may depend upon non-automatized, second-order, symbolic monitoring and commentary.

Goodenough (1993) contends that the elaboration of grammatical arguments not only facilitates the planning and coordinating of social interaction within domestic groups (especially familial groups with the increasingly long periods of child-dependency needed for learning the burgeoning culture) and allows for the cumulation of shared experience, but makes it possible to inform others about nonpresent events of which they were not a part. Grammatical markers for subject and object, indications of time, place, reality/unreality, beneficiary, and relationship provide the materials for the elaboration of symbolic systems of belief, and pave the way for the post-narrative, post-communicative emergence of private speech, tied to reflective language, divorced from activity, and indispensible for individual belief.

It is Donald's (1991, 1993) third stage of cognitive development, that of the externalization of memory, which makes all the more clear the necessity of social interdependency for human cognitive evolution. Mimesis and language, although themselves coevolved with culture, still depend on the internal memory capacity of individuals, however expanded it may be by virtue of its colonization by prefrontal hypertrophy. Biological memory is impermanent, its medium is fixed, and its format is constrained. Indeed, the evolution of internal memory capacities may itself have depended on ways of editing and pruning them. However, the emergence of literacy, and other skills involving symbioses with symbolic external storage, allows memory to be externalized in ways that are enduring, refinable, and even capable of reformatting. External storage also, via the use of a spatialized external information space, allows us to harness vision for reflective thought, to change the part of the brain used for thinking, to interrelate information an images in novel ways, and to develop new cognitive strategies which are socially organized, and can be institutionalized to survive the replacement of member individuals.

External storage thus makes possible an even more thorough invasion and use of the brain by cultural programming, especially institutionalized education, the development and elaboration of new devices (from wax tablets to manipulable computer imaging systems), and new visual symbolic codes. This culminates in the deliberate construction of artifacts which produce particular internal mind-states in recipients, states which, like the world of a novel, may be artifact-dependent for their maintenance. This may change the role of biological memory to be more symbiotic with cultural artifacts, increase demands on certain areas of the brain which, given its neuroplasticity, can expand their territory at the expense of other functions, producing, for example, the loss of rote verbal skills and visual imagination that may come with literacy. Finally, we also face a danger to individual integrity. "Free access to external memory tends to pull apart the unity of mind, fragmenting experience, undermining the simpler mythic throught structures humans have grown rather attached to" (Donald 1993, 164). Nevertheless, this is not the place to rehearse an analysis of the effects of postmodernism on self-identity (but see Cushman 1990, Gergen 1991, and Giddens 1991).

The central point here is that human brains are not evolved to develop in isolation. They are complexly, flexibly, and and only loosely constrained by genetics to internalize a whole range of sociocultural practices. Our brains internalize social practice in ways that, by virtue of our neuroplasticity and prefrontal hypertrophy, profoundly influence our psychological functioning, down to our neurophysiology. Walter Freeman (1995) makes the point that our brains have evolved primarily as organs of social cooperation and understanding, involving the construction of symbolic representation and the development of mechanisms to reach social agreement. Barresi and Moore (1995) have mapped the complexities of how increasingly sophisticated social organisms represent multiple levels of intent, depending on the use of imagination and the extent to which different participants intentions are integrated. Freeman suggests the possibility that our ancestors learned to adapt neurohormonal mechanisms for the reproduction and care of young to reshaping otherwise relatively slow accretions of synaptic change with experience. He suggests that social bonding, the emergence of shared meaning, and the coordination of activity facilitates the unlearning of individual value systems via socially cooperative action, and encourages us to focus not on individual but societal aspects of neurodynamics and neurochemistry. Evolutionary psychologists like Robert Wright (1994) have begun some of this work; a case in point is Wright's (1995) sophisticated analysis of how the relationship between social oppression, low self-esteem, and the low levels of impulse control associated with decreased serotonin might provide a deeper understanding of urban violence.

The origination of putatively individual cognitive activity in social context is amply documented in the psychological literature (Rogoff and Chavajay 1995), and such activities may not only have social origins, but actually be socially distributed, including even memory and problem solving. Early social embedding is a sine qua non of the development of higher functions like language and meaning (Vygotsky 1978, Wertsch 1979). Human intellect cannot be separated from the technologies that extend it; specific linguistic practices result in specific cognitive skills; learning is situated in communities of practice; cognition is socialized by learning "cognitive values" about what and what not to think about; habitual relations can be institutionalized in ways that result in their being viewed as externally imposed; and later generations can lose awareness of intentional structures buried in history. As Benzon and Hays (1990) have made clear, cultural evolution itself can be seen to have produced whole new patterns of thought, as rationalization first appeared in Ancient Greece, theorizing in Renaissance Italy, and model-building in 20th century Europe.

Space limitations forbid a more detailed explication of how our subjective internality, our emotional experience, and our very existence as well-bounded, autonomous, and responsible selves are socially constructed. Further work will also be needed to extend such an account to the sociohistorical constitution of individual souls and spirituality, which have a reality as obdurate and of the same kind as do selves. It has been our present purpose to lay the foundation for such an explication in the neuroanthropological fabrics of our evolutionary and ontogenetic development. We have seen that our extensive neuroplasticity, and our prefrontal hypertrophy, make extensive experiential shaping of our nervous sytems necessary and that, given our extended social dependency well into maturity, that shaping is likely to be socially mediated. We have seen that during the course of mind/culture coevolution, this shaping has also come to include, by virtue of the cortical colonization of many neurological functions, the entrainment of attention and arousal to social contingencies; the elaboration of emotional scenarios from social interdependency, particularly the regulation provided by early familial attachment; and the whole sequence of mimetic, linguistic, and ultimately institutional and artifact-dependent cultural symbioses enabling the emergence of our sophisticated and emotionally engaging cognitive abilities. Finally it is the culture, the community, the family and other human relationships which differentiate and constitute our individual psychology, out of which it is differentiated, and provide the emergent capacities for transcending its limitations.

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