In the extreme, non-participation is exemplified by the individual suffering neglect and denial of left hemiplegia (anosognosia) following a stroke damaging the parietal and frontal lobes of the right cerebral hemisphere. Here the individual’s behavior resembles that of a disembodied mind confronting a world of inert objects with which he or she has no relationship except at a level of verbal fantasy. The disconnection between world, self, and the individual’s place in it may be so severe that the person denies a left sided hemiparesis and is unable to even recognize his own paralyzed left leg or arm as part of himself. When asked to visualize the main street of her home town looking up the street from the south end, such a patient will name all the buildings on the east, right hand side of main street and none or few buildings on the left side of the street. When asked to visualize the street looking down it from the north, she can name all the buildings on the west side of main street and none on the right. Such a patient may claim that he is able to pick up a tray with several breakfast items on it and attempt to do so. The effort fails because grasping and lifting the right hand edge of the tray with the right hand, while the paralyzed left hand remains motionless, leads to all items on the tray sliding off to the left.

These individuals lose the parts of their brains that are necessary for participatory consciousness (noncognitive prehension) with the left side of the world.  Because of overexuberant left hemispheric specialization for language and praxic tasks, the areas for left world prehension are in some individuals restricted to the right hemisphere.  When a stroke disables the right hemisphere in these rare individuals they are simultaneously unaware of the left side of the world, as seen or imagined from their current perspective, and unaware of being unaware.  Such a patient, asked to clap her hands, flaps the right hand in front of her while the left arm remains motionless at her side. When asked whether she had succeeded in clapping, she answers that she did. Asked to point with her left hand to the doctor's nose (and again the arm did not move), she was asked, "Are you pointing to my nose?" She answered, "Yes, it is about two inches from your nose." (Ramachandran et al, Illusions of body image: What they reveal about human nature, In: The Brain-Mind Continuum, Llinas & Churchland (Eds.) 1996)

This patient's answer, "Yes, it's about two inches from your nose," reveals a previously unappreciated, critically important aspect of this condition. These patients are unaware of their illness and left sided hemiparesis because their left hemisphere-dominated brain is generating apparitions (phantoms) of a normal left side. It is not a case of not noticing the left side, "neglect" is a seriously incorrect name for this situation.  Instead it is a case of perceiving a complete world in which the constituents of the left side are phantoms. [Note: if this is so, why the case of not being able to visualize the left side of main street? This requires that spatial memory is the re-activation of a perspectival construct?] The woman in question saw an apparition of her left hand "about two inches" from the examiner's nose. While making the "sound of one hand clapping," she saw a (phantom) hand and heard the (phantom) sound of hand claps. According to Ecological Neuroscience (i.e., neuroscience that admits participation), this is the normal, expected behavior for a person with a certain right hemisphere brain lesion!! To wit: the lesion disables the part(s) of the brain that is(are) necessary for our awareness of real objects, persons (and parts of persons), and events in the real world.  It temporarily blocks noncognitive prehensions from the left side of the world. The predominance of language processing tasks, where signifiers stand for the real in the left hemisphere, so strongly biases it towards representations that it is unable to provide for prehensions except for the right side and so it automatically supplies apparitions (phantoms).  The left hemisphere thus completes the situation in a way compatible with the only affect that it knows, positive affect. This accounts for the inappropriate lack of concern that such patients routinely exhibit, as well as the absence of guilt or embarrassment on task failure. It is a mystery to them why they failed, so the left hemisphere, true to the first law of organismic neurobiology (the brain always works as a whole) as it is obliged to be, confabulates, e.g., "arthritis," "clumsiness," or "tiredness."

This perspective implies that ordinarily conscious perception is of and with reference to a "virtual body," or body schema that is constantly being updated by visual, postural (vestibular), muscle proprioception, auditory, chemoreceptor (taste & smell), and tactile information.  In the case of anosognosia, the virtual body is not being updated via noncognitive prehensions regarding the left world, so that portion of it's reality vanishes from consciousness, replaced by an illusory left world provided from past traces by the left hemisphere.  The dependence of the body schema on sensory input establishes the brain-dependence of embodied conscious experience, its representational character, and our sensitivity to illusion.  The direct experience of the world via organismic entanglement, wherein we enter into momentary prehensive unifications with other organisms, normally causes our sensory mediated perception to be closely congruent with the world around us.  It is, in fact, a necessary connection if we are to perceive a world!  I propose that the virtual body is the superposition of the wave function of one's Self, which must be a kind of prehension with the implicate order, with the prehension of one's body (one's particle aspect?).  This idea is compatible with the fact that the body schema is not limited to the corporeal body, with out of the body experiences, and with the appearance of apparitions (including heautoscopy).  I expect that some such scheme, which makes full use of the concept of prehension and which applies it to all organisms (in the Whiteheadian sense), will be a powerful way to formulate a coherent view of things.