Body, brain and behavior: the neuroanthropology of the body image by



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BODY, BRAIN AND BEHAVIOR:
THE NEUROANTHROPOLOGY OF THE BODY IMAGE

by

Charles D. Laughlin*



Abstract: The author presents a biogenetic structural theory of the body image in human beings. The theory accounts for both the universal principles and the variance in body image cross-culturally. All humans develop a neurocognitive model of their body which combines information about the body obtained via both the internal and external sensory systems. Their experience of themselves is mediated in part by this model. The initial model of the body is "hard-wired" and already present and active in the cognitively and perceptually competent pre- and perinatal human being, and develops as a consequence of both genetically imposed and socioculturally influenced processes of growth. The role of behavior in this process is shown to be the control of perception such that the body image experienced in perception approximates that anticipated by the cognized self. The theory accounts for the use of the body-as-symbol and the distortion of the body image for communicative purposes. The neurophysiology of imagery is reviewed and suggestions are made for possible clinical methods that might be used to effect therapeutic changes in pathological body imagery.


By means of perpetual alterations in position we are always building up unwittingly a model of ourselves, which is constantly changing. Every new posture or movement is registered on this plastic schema and the activity of the cortex brings into relation with it each fresh group of afferent impulses, evoked by a change in the position of the body. The psychical act of postural recognition follows, as soon as this relation is completed on levels that are not associated with consciousness.


Sir Henry Head, Aphasia and Kindred

Disorders of Speech

For the error bred in the bone

Of each woman and each man

Craves what it cannot have,

Not universal love

But to be loved alone.


W.H. Auden

INTRODUCTION

Anthropologists have encountered a dazzling array of cross-cultural variance in body image, and have occasionally realized the importance of the body image and its symbolic modification in our understanding of culture (Turner 1971, Seeger 1975, Blacking 1977, Scheper-Hughes 1989, Scheper-Hughes and Lock 1987). For instance, what is considered attractive about the body of the opposite sex will differ among cultures (Hallinan 1988). Moreover, the meaning of the body may vary widely even among individual members of any particular society. As clinicians can attest, many perplexing psychological problems (like anosognosia, phantom limb, unilateral neglect, anorexia and bulimia) manifest as distortions of the body image and behavior relative to the body image (see e.g., Critchley 1965). Also, the semiotic aspect of the body image is central to the world view of many peoples. Indeed, there is evidence that shamanic cultures everywhere place the human body at the center of the cosmos, a motif that George MacDonald et al. (1989) have called the "somatocentricity" of cosmology. It is important to note that, so far as I am aware, there does not exist a society anywhere on the planet among whom members do not transform either the male or female body (or both) in a symbolic manner. In other words, the interpretation of the body as symbolically meaningful is universal.

Following in the tradition of Sir Henry Head (1920, 1926), I wish to present a neuroanthropological theory of the body image that will account for both its variety and its universal aspects.1 In the discussion that follows, I will support the following three premises that I feel to be requisite to a full explanation of the clinical and ethnological significance of the body image:

1. The body image is a construct of the nervous system. An individual's experience of their body is produced by neurocognitive models that develop from initial pre- and perinatal neural structures (primarily proprioceptive, interoceptive, intentional, and object perceptual neural networks) and that come to incorporate sensory perception, affect, input from skeletal muscles, memories of past bodily states, etc., into a more or less dynamic body image.

2. The real body is always a transcendental object relative to the body image. That is, the real body is always more complex and transformative than can ever be modeled by the nervous system. Moreover, there is always far more occurring within an individual's body image than can be brought to consciousness at any moment. In other words, intentionality relative to the body image always excludes more information than it includes.

3. Behavior functions to control perception so that the body perceived matches that expected based upon the body image. Behavior is part of a cybernetic, neurophysiological, negative feedback loop that operates to produce and maintain the perceptions desired, anticipated and expected by neural models. The models producing an individual's body image may be evoked by external stimuli penetrating as symbols, or may initiate internal operations and behavior to fulfill their own expectations about the body.

In the discussion that follows I will offer a general description of how the human nervous system models its environment and its own organism. I will then incorporate what is known about the neuropsychology of imagery and generate a working theory of the body image. I will close the discussion by addressing some of the problems related to the body image that are of interest to anthropologists and clinicians, and will suggest some techniques for changing the body images of individuals seeking clinical assistance.

THE COGNIZED ENVIRONMENT AND THE BODY IMAGE

Reality as we come to know it is a cognitive and perceptual construction produced by the nervous system, and is formally constrained in its nature by the internal structures of the perceiving organism. Both the external world and the experiencing organism, as we know them, are essentially produced by the activities of neural models.2 These models exist within and as a part of the immensely intricate organization of the fibers comprising our nervous system, especially those fibers comprising the cerebral cortex.3



Neurognosis and the Roots of the Body Image

The course by which the nervous system comes to know about the organism of which it is a part, and the environment within which the organism is ensconced, is a well ordered one from beginning to end. The neural networks comprising our knowledge and experience have their developmental origin in initial neurognostic4 structures that are present before, at, or just after birth, and that manifest an organization which is largely genetically determined. There are several neurognostic structures that form in early pre- and perinatal life and that participate in forming the initial organization of an individual's body image. These include: (1) the neonatal perceptual system which is neurognostically structured to apprehend and explore objects (Burnham 1987, Streri and Spelke 1988); (2) the bilateral asymmetry of cerebral functions, which is already present in the anatomy of the fetal brain, and which produces an alternation between the rudimentary conceptual and temporal planning associations subserved by the left hemisphere and the imaginal-metaphorical and atemporal gestalt associations subserved by the right hemisphere; (3) the intentional processes subserved by the prefrontal cortex that select objects of interest and disattend objects of no interest; (4) proprioceptive (input from muscles, tendons and joints, as well as vestibular organs) systems that are present and operating in the fetus and that provide spatial, motion and balance information to postural schema (cognitive map of the body's posture) in the somaesthetic cortex; and (5) interoceptive (input from the internal organs of the body) systems that provide sensory inputs pertaining to hunger, thirst, pain, nausea, etc. to the sensorium.

Although there is remarkable selectivity in the developmental reorganization of these early structures, development of all neural structures is neurognostically regulated. Some potential organizations deteriorate, others become active, and still others remain relatively latent and undeveloped (see Changeux 1985, Edelman 1987, Varela 1979). This selectivity is one reason why there is such remarkable variation in cognitive adaptation to the essentially turbulent and evolving nature of the organism and the world.

The Cognized Environment and the Body Image

The organism and its environment are inextricably linked in an intricate dance, coupled for a lifetime in an increasingly complex process of mutual adaptation.5 In the process of its self-cognization, the organism becomes a relative abstraction to itself, and will involve to some extent a conceptual and imaginal abstraction of its self from the matrix of its environment. The organism develops a model of itself which comes to be defined through the emerging complexity of its own internal organization. The principal attribute of the organism's model of itself is the production and conservation of this self-organization while addressing the demands of adaptation to events in its environment (Varela 1979, Maturana and Varela 1980). From a complex system of such models we erect a cognized environment. The cognized environment is how we know and experience our organism and our world, and yet the system of neurological transformations that produce the cognized environment is part of the very world within which we are embedded and to which we must adapt in order to survive. Both the world and our organism, as they really are apart from our knowledge of them, comprise our operational environment,6 and can be considered transcendental relative to our cognized environment. That is, there is always more to learn about the operational environment, or any form within it, than can be cognized (see Martin 1981:102 on this issue).



The Body Image as a System of Entrainments

The internally constructed models which comprise our cognized environment are to the operational environment as maps are to a landscape. The models comprising our cognized environment include those that model our organism, and among these are the models that mediate our experience of our body, or physical self. These latter I will call collectively our body image.7 Our body image may thus be considered an organization that is comprised of neural networks that are nested within other networks whose content is composed of symbolic transformations of meaning at various levels of organization from primitive arousal, vestibular, postural, metabolic interoception and affect to more advanced conceptual and imaginal functions. These transformations have their material reality in neural coordinations, or entrainments,8 whose initial forms are neurognostic, whose eventual developmental complexity will be variable and whose evocation may or may not be environmentally triggered. What we understand about ourselves is the function of an organization of models that become developmentally stabilized. It is a major function of the body image to differentiate aspects of the organism in order that the organism may adapt to its very transcendental nature.



Intentionality and the Body Image

As with consciousness generally, the ongoing, moment-by-moment operation of a person's body image is essentially intentional in organization; that is, neural networks producing that body image tend to organize themselves about the phenomenal attributes of the body. The phenomenal attributes of the body are themselves produced in experience by neural models in the sensorium and are, for the moment, the central focus of conceptual, imaginal, affective, metabolic and motor operations of the organism towards itself (Neisser 1976: 20ff). For example, if you look at yourself in the mirror, the visual image of your exterior body may become the intentional locus of thoughts ("I have to get a haircut"), feelings ("God, I'm too fat!"), behaviors (shaving, brushing teeth), etc.

It is crucial to understand that the intentional processes that construct and constellate experience upon one's body image are cybernetic and largely cortical in organization. Intentionality derives primarily from a neurognostically patterned dialogue between the prefrontal cortex (Fuster 1980, Stuss and Benson 1986) and the sensorial cortex of the brain (Laughlin 1988). Constituent structures entrained to the body image as a consequence of the dialogue between prefrontal and sensorial processes may be located over a wide expanse of cortical (eg., frontal somaesthetic structures, parietal visual attention structures, right lobe imaginal structures, left lobe language and conceptual structures), subcortical (eg., hippocampal recognition structures, autonomic postural structures, brain stem arousal structures, limbic emotional structures) and endocrinal (eg., hypothalamic and pituitary structures) tissues.

Experience9 of the body is a function of this intentional dialogue, and involves the constitution of a phenomenal body within the networks of cells comprising the sensorium, to which are entrained the cognitive processes that associate meaning and form in a more or less unitary frame (see Johnson 1987). The sensory and the cognitive-intentional aspects of the "lived experience of the body-self" (Scheper-Hughes and Lock 1978) are never passive. Rather, they are active products of neurological functioning, and are exquisitely ordered in the service of abstract pattern recognition, both in moment-by-moment adult experience (Gibson 1969), and in development from the earliest periods of pre- and perinatal consciousness (Chamberlain in Verny 1987, Laughlin 1990a, Parmalee and Sigman 1983).

But we must be cautious in implying that all neural processes entrained within intentionality are conscious, for this is far from the case. Active neural processes may or may not be experienced within the intentional frame. As Henry Head (1920:606) noted, most of the structures that may subserve the conscious experience of the body are themselves operating outside of consciousness, as is usually the case of the schema retaining knowledge of posture and position of the body in space. For example, as the literature in cognitive therapy has shown, unconscious "automatic thoughts" (or cognitions) about an object of consciousness may intervene between perception of and feelings about that object (see Beck 1967, Beck and Emery 1985). And the object may well be one's own body image. It may well prove to be unconscious and "automatic" cognitions that account for some clinically significant distortions of the body image. The body image may be evoked either externally via the sensory apparatus of the sensorium (e.g., I perceive my hand "out there"), or internally via either the imaginal structures of the sensorium (e.g., I dream that my body falls down a tunnel), or the internal sensing apparatus (e.g., I feel achy or hungry; or I sense I am sitting in a chair).



The Role of Behavior in the Control of Body Perception

One of the most important issues I must address relative to the cognized environment, and its constituent body image, is the role of behavior as a phase in the cognitive-intentional control of perception.10 William T. Powers (1973) in his book, Behavior: The Control of Perception, has gone a long way toward modelling the function of behavior relative to perception. His thesis is as simple as it is controversial, and is worth considering at length, for it is it is the failure to understanding the internal cybernetic function of behavior that has thwarted the production of a general theory of the body image sufficient to account for both the cross-cultural and the clinical variance in body image.

According to Powers, behavior is never an end in itself, but is always a phase in a greater neurocognitive loop by which an object of interest is brought before the perceiving subject and kept there as long as desired, despite disturbances produced by other competing objects. Behavior is thus negative feedback (ibid:54) which operates to perpetuate the goal of perception and to control responses to disturbances that might otherwise detract from that goal. Behavior is an exercise of motor control over change of state by the perceiving organism (ibid:47-48, 50). For example, driving a car from point A to point B requires a series of moments of consciousness during which behavior continues to produce the perception of "staying on the road" -- moreover, "staying on the right road."

Applying the Powers model to the body image, we can see that behavior that transforms the symbolic form of the body is behavior intended to produce a desired perception of the body. The perception desired may be visual, olfactory, somaesthetic, interoceptive, or a combination of these senses. Thus I may act to dress my body, to have a barber cut my hair, to apply chemicals, to use certain intonations of speech, etc. so as to produce the experience of my body that I desire, or that I perceive is desired by others. I may eat or refuse to eat, exercise or not exercise, wear body-altering "foundation" garments, etc., all to the purpose of appearing to myself and others as desired. Depending upon gender and cultural circumstances, I might go so far as to apply (or have applied to me) paint, scarification, tattooing, surgery, ornamentation, a wig, etc., in order to effect this end. And my behavior, especially in public, would tend to be geared in part to maintaining my own and others' desired perceptions of me.

It is of significance, especially to the understanding of clinical syndromes, that desire may be unconscious to the actor. That is, unconscious complexes may determine the body image desired while the consciousness merely remains a witness or rationalizer for the perception-fulfilling behavior. This would seem to be operating in at least some cases of anorexia and bulimia.

Evocation, Fulfillment and Expression of the Body Image

Because neural models are living systems, causality involving their activity is both complex and reciprocal (see Blalock 1969 and Ackoff and Emery 1972 on reciprocal causality in living systems). Any model within the cognized environment either may be evoked by events outside of itself, or may seek fulfillment in those events. These processes are operating with respect to the body image as well. For example, hunger sensations arising through interoceptive input may make me aware of my body and its needs (this is the evocative mode of the body image), or I may seek the perception of my form in a mirror "to check out my appearance" (the fulfilling mode of the body image). In addition, the body image may be manipulated for the purpose of expressing some aspect of the cognized self. For example, I may wear certain clothes to a party in order make a particular impression (the expressive mode of the body image). In other words, my body image is not a passive entity, but rather is an active agent in either initiating behavior or operations that fulfill or express itself, or in reacting to evocative stimuli that penetrate to perception and thence to its entrained networks. If I imagine cutting my finger, my body schema may well react as if my finger had actually been cut. The image of the lesion penetrates into the structures of the body image and evokes appropriate responses. Alternatively, my body experiences hunger and initiates fulfilling behavior that will produce the perception of food and eating, or expressive behavior that communicates this need to someone else.

Again, as Henry Head repeatedly emphasized, the process of behavioral control -- and the fulfilling, evocative and expressive modes of this control system -- need not be conscious. A distinction should be made between perception and conscious perception, for behavior may operate purposively to keep an object before perception without an individual being aware of the operation (Powers 1973:35). This distinction is important, for much of the behavior we notice relative to the body image may be unconscious to the actor. For example, my postural behavior may be determined by a largely unconscious desire to attract and hold the attention of another individual.

IMAGERY

So far I have been speaking of the body image in general biogenetic structural terms; that is, of the entire system of models that produce an individual's meaningful experience of their body -- models that subserve sensorial, conceptual, memory, imaginal, affective, and behavioral functions. I now wish to focus upon the imaginal aspect of the body image in more detail. The neuropsychology of imagery is, itself, a complex matter, and one that I need to synthesize with our theory before I can proceed to a more precise working theory of the body image.

Among other things, I must be clear what I mean by "image," for there are actually many types of images, and what we normally mean by "body image" incorporates features of several of these types. In one of the best books written on the psychology of imagery, Peter Morris and Peter Hampson (1983: 65) discuss a number of types -- primarily of visual images11 -- including memory images (those that are aroused from memory of past events), imagination images (those that may include material from memory, but that are newly constructed without reference to past events), after-images (those produced after staring at an object and then closing the eyes or looking at a neutral surface), dream images (those occurring during sleep), hallucinations (those projected "out there" and perceived as real), hypnagogic/hypnopompic images (those that occur during the onset of sleep, or while waking up), and eidetic images (those that occur very vividly, but are not perceived as real).

Of these various types of imagery, we are primarily concerned here with imagery that derives from the combination of memory and perception, for this is the type most directly involved in operations and experiences of the body image. We are secondarily concerned with eidetic imagery which may be used to transform a body image of the former sort.12



Properties of Images.

After reviewing the wealth of research material available on the psychology of imagery, Morris and Hampson (1983: 202-203) summarize the general properties of images. I will reproduce their list of properties here, adding our own headings for each property to make their list more succinct:

1. Abstraction. The information from which images are constructed is represented in long-term memory in an organized and interpreted abstract format.
2. Penetration. Depictive and descriptive information can be used to generate visual images, a process which will take time, with more complex images taking longer to construct than less complex [images].
3 Inspection and Scanning. Once it has been generated, the surface image can be scanned and inspected. The longer the distance scanned the longer it will take, and the larger the property to be detected the quicker it will be spotted.
4. System Limitations. The processing capacity of the imagery system in general and its ability to display conscious images in particular is limited. [Processing may involve the expenditure of effort.]
5. Reverberation. Surface images need to be regenerated continuously to sustain them. Scanning the surface image may help in its maintenance by revealing which parts need to be refreshed.
6. Image Transformation. Images can be transformed in a continuous fashion, by operating directly on the display as in mental rotation or scanning.

7. Memory Induced Transformation. On the other hand, images can be modified by activating different parts of the long-term data base....


8. Transformation of Part or Whole. Transformations of the surface image can be applied to the whole [field] or part ...of the image display.
9. Perception and Imagination. Images tap the perceptual processing system at many levels including those that cannot be consciously monitored....
10. Vividness. Often, the more vivid the subjective image the stronger are its percept-equivalent effects. ...images can act as the inputs to, as well as the outputs of perceptual processes.

It is well to note that all types of imagery are produced at least in part by sensorial structures, and that all types hold at least some of these structures in common with perception (Kosslyn 1980, 1983). The implication here is that intentionality may fulfill itself in sensorial events without the necessity of external perception. In other words, an image may complete the process of fulfillment of a neural model without reference to external events (e.g., in dream imagery and hallucinations).



The Neuropsychology of Imagery.

A controversy of long standing rages in the psychology of imagery. On one side of the debate are those like Pylyshyn (1984) who hold that verbal and nonverbal symbolism are but epiphenomena of the tacit computational processes of cognition. On the other side are researchers like Kosslyn (1980, 1983) and Paivio (1971, 1986) who argue that verbal and imaginal systems are two distinct and sometimes independent modes of representation. Fortunately for our purposes, nearly all of the neuropsychology available comes down on the side of the latter view, the multiple representation model (see Bogen 1969, Bogen et al. 1972, Geschwind and Galaburda 1984, Sperry 1982, Ley 1983, Bryden 1982, Gazzaniga 1970, Gazzaniga and LeDoux 1978, Paivio 1986).

Neuropsychological data suggest that the cortex of the human brain is organized into distinct and interacting functional areas that process information differently depending upon the adaptively appropriate, abstract qualities being extracted by each area. The sensorium is a part of the neocortex and is itself divided into distinct functional areas, as well as areas that specialize in combining multimodal information within unitary models of objects and events in the world (we can recognize a person by the sound of their voice or by the form of their face). Abstract qualities produced in, and abstracted from, raw sensation (such as color, line, form, etc. for vision, or frequency, direction and distance for audition) define the parameters of recognition and cognitive, affective and motor association.

There appears to be an asymmetrical predominance of right hemisphere processing of nonverbal imagery, and of left hemisphere processing of verbal symbolism. But caution must be exercised in attributing all imaginal processing to the right hemisphere, for, as Paivio (1986: 260) notes, predominance of one hemisphere over the other may be accentuated with more abstract meaning and disappear with more concrete meaning. For example, recognition of common, concrete objects presented visually seems to be distributed equally in both hemispheres. The left hemisphere does seem to demonstrate a dominance for visual recognition of language text, and auditory recognition of spoken words, but Paivio (1986: 260-261) suggests that this dominance may apply only to words representing abstract concepts and may disappear with words representing common objects. And the right hemisphere seems to specialize in associating faces with emotions (Hughlings-Jackson 1879, Galin 1974, LeDoux and Hirst 1986:294), and in recognizing of melodies and the nonverbal sounds made by common objects (Kimura 1973, Bryden 1982).

The best information I have suggests that the more abstract the meaning associated with nonverbal imagery, the more the right hemisphere predominates (Ley 1983, Paivio 1986) in establishing, retaining in memory and processing those cognitive associations. Moreover, the left hemisphere predominates in the processing of analytical and sequential ordering in knowledge, whereas the right hemisphere predominates in processing synthetic, simultaneous spatial relations. Imagery evoking emotional associations would also seem to be processed primarily in the right hemisphere. Thus nonverbal imagery (like that involved in producing the body image) associated with both affective and complex, abstract, multimodal and intuitive cognitive associations will tend to be produced by networks largely (but not exclusively) located in the right hemisphere.

Yet the brain works as a unit and the hemispheres are intimately interconnected across the corpus callosum and other commissures. Complex meaning primarily associated with nonverbal imagery and produced primarily by right hemisphere tissues may become associated with left hemisphere conceptual structures and be expressed via left hemisphere language functions (e.g., written scores of melodies, mythic stories). Likewise, cross-talk between the hemispheres may result in left hemisphere conceptual knowledge being expressed via right hemisphere imagery (e.g., illustrations, metaphors). However, early associations between imagery and emotion may become, as it were, encysted and relatively unaccessible to left hemisphere mediated rational faculties that develop later. This would appear to be what is happening with emotional-imaginal complexes resulting from early trauma and producing neurotic symptoms later in life.



Eidetic Imagery

Let us turn now to a brief look at eidetic imagery -- that is, the ability to wilfully construct a vivid image in the mind's eye. First of all, the data suggest that, among North American subjects at least, the ability to produce eidetic images is rare (10% - 15% in children; Morris and Hampson 1983: 88). This is not a skill encouraged in our culture by either informal enculturation or formal education, with the exception of the relatively recent "new age" holistic health movement. Second, maintenance (or perseverance) of an image usually requires conscious effort, whereas other kinds of imagery, such as fantasy, hypnagogic and dream imagery may occur spontaneously and even unconsciously (Gorman 1969:5). Third, eidetic images tend to be more static within the mind's eye than other types of images which may involve a great deal of motion or rapid transformation. Fourth, intensive concentration upon eidetic imagery may lead to the spontaneous occurrence of other types of imagery (e.g., dreams, visions, hallucinations, etc.). In other respects eidetic imagery is much the same as the other types of imagery described above.


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