An unusual late-career turn toward neuroscience
By 1976 Ida was eighty years old and had been teaching Structural Integration for nearly three decades. Her doctrine on the autonomic nervous system, the cervical plexi, the role of fascia, and the structural relationship of pelvis to thorax was largely settled. What was not settled — and what she seemed increasingly to want her senior teachers to think about — was the question of how the human sensory apparatus had arrived at its current form. In the second Teachers' Class she read aloud, at length, from a paper on encephalization in mammals. The reading is not casual. She returns to it, pauses to gloss it, and presses the senior practitioners present to grasp what is at stake. The stakes, in her framing, are that the nervous system of the species you are working on is the product of specific evolutionary pressures, and that those pressures shaped which information enters the body at all.
"They had improved auditory and olfactory systems, and their visual systems were modified with rod cells taking the place of cone cells. Both changes were appropriate for animals that were active at night. The evolution of hearing and smell to supplement vision as a distant sense is sufficient reason for the evolution of an enlarged brain in the earliest mammals. The reason is to be found in the way neural elements are packaged in vertebrate sensory systems."
She begins with the deep evolutionary background — why the earliest mammals developed enlarged brains at all.
The packaging argument is the structural insight that draws Ida in. A lizard's retina contains a million sensory cells and a hundred thousand ganglion cells; all of that visual computing happens out at the eye, before the signal reaches the brain. An auditory animal, by contrast, has only a few hundred sensory cells in the ear — almost everything the ear's signal will become must be built inside the central nervous system. To become an auditory or olfactory creature, in other words, you have to grow a bigger brain. This is the kind of argument Ida liked: a structural constraint dictating what looks, from the outside, like an intellectual advance.
"There is no space for these in the middle and inner ears. The obvious place to package the additional material is in the brain itself, and solving the packaging problem would therefore require the enlargement of parts of the brain involved in audition. A similar argument would apply to an olfactory animal, since increased dependence on the sense of smell would require expansion of the forebrain, systems that contain the integrative neurons of the olfactory system. As we see that the first expansion of the vertebrate brain may have been primarily a solution of a packaging problem. Now to me, this is a mighty interesting concept. They just decided to put all put them all together rather than have them localized."
She lands the central claim — the brain grew to hold the new senses, and intelligence may have been incidental.
Visual encoding versus auditory and olfactory encoding
Having established that hearing and smell required brain space that vision did not, the paper Ida is reading then turns to a deeper question: how do these different senses encode information at all? Vision has an enormous structural advantage, one that Ida — a chemist by training who had spent decades thinking about geometry and arrangement in tissue — clearly found compelling. The eye is a grid. Light landing on a specific retinal cell labels its own location automatically, because the optics of the eye and the geometry of the retina constitute a spatial code by their very arrangement. Sound and odor have no such code available. They are temporal phenomena, not spatial ones, and any spatial information they carry must be constructed by the nervous system from temporal patterns.
"Visual information is encoded at a retinal level with a structurally determined spatial code. The optics of the eye and the arrangement of retinal elements provide a grid that labels the location of stimulated cells. No such code is possible for sound or odors."
The structural code in the eye:
This last point — that sound and odor must be turned into spatial information through some other mechanism — is the puzzle the paper proceeds to solve by example. Bats and dolphins and other echolocating animals have evolved an extraordinary trick: they emit sound and listen to the timing of its return, and from that temporal pattern they build a model of where objects are in space. The auditory system, in echolocators, has solved a problem the visual system solved by anatomy. Ida pauses here. She wants her teachers to grasp that consciousness itself — the experience of a world made of objects arranged in space and time — is not given; it is constructed.
"Animals that use echolocation to identify the sources and shapes of distant objects do it by translating spatial information into a temporal code. And so we have the basic constructs of human conscious experience, objects in space and time."
From echolocation she draws the broader lesson:
It is worth pausing on what Ida was doing by reading this passage to a roomful of senior practitioners. She was not training them in neuroscience. She was asking them to dismantle a naive assumption — the assumption that the body they were working on perceives the world as it is. The body they were working on perceives a model the brain has constructed, and that model is the species' inheritance of certain evolutionary trade-offs. The eye gives space cheaply; the ear and the nose pay dearly for space; the brain enlarges to cover the difference.
"The work of the brain is to create a model of a possible world rather than record and transmit in the mind a world that is metaphysically true."
She underlines the philosophical payload:
Why mammals shifted to hearing and smell
Having laid out the encoding problem, the paper returns to the historical narrative. Why did the early mammals depend so heavily on hearing and smell? Because they were nocturnal, and because they had been pushed there by the dinosaurs. The therapsids — mammal-like reptiles of the late Paleozoic — had once been the dominant land animals, but they lost the daylight niches to the dinosaurs over roughly a hundred million years, and survived only as small night-active creatures whose visual systems became rod-dominated and whose hearing and smell carried the load. The mammalian brain, in this telling, is a brain shaped by darkness. Ida pauses on this. The animal lineage that gave rise to humans was, for a long stretch of geological time, a lineage of small nocturnal creatures listening and smelling in the dark.
"The dinosaurs and therapsids were clearly in a kind of competition for the normal niches of land reptiles, and the mammal like reptiles lost the competition, becoming completely extinct by the mid Mesozoic era about a hundred and fifty million years ago, the niches for which the therapsids competed and lost were for large diurnal animals that used vision as the normal sense for receiving information about events at a distance. The earliest mammals were a persistent remnant of only slightly modified therapsids, and they survived as small, nocturnal animals. They had improved auditory and olfactory systems, and their visual systems were modified with rod cells taking the place of cone cells. Both changes were appropriate for animals that were active at night. The evolution of hearing and smell to supplement vision as a distant sense is sufficient reason for the evolution of an enlarged brain in the earliest mammals. The reason is to be found in the way neural elements are packaged in vertebrate sensory systems."
She reads the historical sequence:
Ida's interest in this material was not antiquarian. The argument has direct implications for what the practitioner is doing with the cervical plexi, with the autonomic system, and with the question of where in the body perception lives. If the brain enlargement of early mammals was driven by the need to package hearing and smell, then the cranial and cervical structures that house and feed those senses are, in evolutionary terms, the oldest parts of the perceptual apparatus. The visual system is younger, in the sense that its primary computing happens out at the retina; the auditory system is, in encephalization terms, the senior sense that demanded central neural real estate.
The hominid problem — wide range, weak nose
The paper Ida reads then steps forward in time to the hominid line. The argument here is subtle and is the part Ida lingers over longest. The hominids were non-arboreal primates that had moved into a niche comparable to that of predatory carnivores — wolves, big cats. But unlike wolves, the hominids had a poor sense of smell. Wolves mark and map territory through olfactory labels; a wide-ranging social carnivore with a diminished nose cannot do this. The argument the paper makes is that the hominid sensory mix — strong vision, strong hearing, weak smell, plus social organization and a vocal apparatus — required some other way of labeling and marking a perceptual world. The candidate solution is language.
"The development of adequate labels to mark the range may have required the further development of auditory, visual, and particularly vocal capacities, the last of these acknowledging the fact that primates are noisy animals."
She reads the hominid argument:
The step the paper takes here is the one Ida finds most provocative, and she reads it slowly. Language, in this account, did not evolve primarily for communication. It evolved as a perceptual labeling system — a way of marking a world the nose could no longer map. Communication came later, as a side effect of having a labeling apparatus capable of being directed outward at other organisms. This is a striking inversion of the usual story, and Ida wants her teachers to feel its weight. The vocal capacity of the species, in this reading, is a sensory development first.
"that the role of language in communication first evolved as a side effect of its basic role in the construction of reality."
She lands the inversion:
A student in the room, hearing this, immediately catches the implication: in order to develop a language, you have to pull away from immediate experience. You have to abstract. Ida concurs — yes, abstraction. The hominid step into language is also the hominid step away from direct perceptual immersion. The paper she is reading puts this in evolutionary terms: the language system was selected for as an analogue of other sensory-integrative systems, which are themselves unusually plastic and modifiable by early experience. Whorf and Sapir, the paper notes, had pointed out long ago that this same plasticity allows different societies to construct different realities, sometimes with catastrophic effects on how human communities interact. The capacity to build a world by labeling is also the capacity to build incompatible worlds.
Sight and the cervical plexi — what the practitioner can change
Alongside her reading of the encephalization paper, Ida returned several times in the 1976 advanced class to a much more practical question: why do clients report seeing better during the first hour of work? She did not have a confident answer. What she had was a set of observations — students would interrupt a first-hour session to say they could suddenly read the corner of the room, see the spider webs on the ceiling — and a hypothesis about the autonomic nervous system. The visual organ, in her framework, is a highly differentiated outgrowth of the nervous system, and its energy supply is mediated by the cervical plexi of the autonomic. Reorganize the cervical region structurally, and you may alter the energy supply to the eye.
"But you see, you can see the speed and expect to see, to say the same things about all organs of perception. They are highly differentiated outgrowths, if you like, want to call it that, of the nervous system with specialized jobs. And to a certain extent you are able to influence them through that wonderful old autonomic nervous system. Psyche particularly well here in Cuba. And interestingly enough the major influence on these organs comes through the innovation of the cervical plexi. The cervical plexi of the autonomic nervous system."
She gives the framework — perception organs as outgrowths of the nervous system, fed through the cervical plexi.
What is striking about this thread is the explicit appeal to evolutionary seniority. The autonomic system, Ida emphasizes, is the older nervous system — the one that preceded the central nervous system. The senses, being highly differentiated outgrowths of nervous tissue, are mediated by both, but their energy supply comes through the autonomic. The historical sequence she lays out in the encephalization reading — old senses (smell, hearing) packaged in old nervous structure, newer central elaboration on top — finds its echo in her practical anatomy. The cervical plexi sit at the junction. Ida is asking the senior class to take this seriously as a research program.
"There is a big field of possible specialization. Specialization for sight, specialization for hearing. Specialization even for voice. If you want to go into that sort of thing, then the first place you've got to go is study that good old autonomic nervous system. Why do I say good old? Because it is the old nervous system. It is the one that preceded the central central nervous nervous system. System. And if you decide that this is what you're going to do, then you have to get busy and do something about getting Now I am not doing this job for you. If you wanna know about it, you, Jolly, will get busy, and you consult various books and you find out, you direct your attention to is what I really mean."
She names the research program:
Ida is honest about the limits of her own understanding here. She does not know why the cervical work changes sight. She does not know why it sometimes does and sometimes does not. What she knows is that the visual organ is fed by autonomic innervation through the cervical plexi, and that when she or her students restructure the cervical region, sight occasionally improves in ways that have no place in the standard ophthalmological story. The honest acknowledgment of not-knowing is itself instructive. Ida treats sensory perception as an open frontier for the practice, not a settled domain.
"See where they are, see what goes from those plexi to the organs, to the sensory organs. How you think you can get more energy to those sensory organs. Try it. And you may come up with something that you don't believe possible. These people will say, we have seen better. Except that it is that overall, that premise of overall ease, of overall balance that I've been trying to get you to grab hold of. As I also said, it is not a simple field. Just going and finding out where the preautonomic plexi in the cervical area are and just working with it does not necessarily give you better sight. Why not?
She admits the gap:
Living in a field of senses
Behind both Ida's evolutionary reading and her practical anatomy is a larger framing she returns to often: the human being is a local condensation of energy in surrounding fields, and the sensory organs are the local mechanisms that allow specific fields to feed and inform the organism. Light is one such field, sound is another, and the gravitational field — the one she is most concerned with — is a third. Each sense developed to make a particular field available. This framing, while metaphysically loose, is what lets Ida treat vision, hearing, and structural orientation in gravity as members of the same family. They are all ways the body extracts usable information and energy from fields it lives inside.
"people are fields operating in fields. That within you, you have local areas which have apparently been developed to be able to utilize the fields in which you live. As for example, light, there are local areas in you that make it possible for you to utilize light to inform you of what is going on at a distance. That light feeds, apparently, the local levels which deceive him. You take a man and put him into a dark place indefinitely indefinitely and and he he becomes becomes blind. Blind. Not Not only only that, that. In order to preserve his vision, you have to permit him plenty of light. I'm not necessarily talking about bright sunlight, and that which is plenty of light to you may not be plenty of light to me, but it's plenty of light in terms of this perceptive organ. Now when it comes to hearing, you've got the same problem. You have local areas that can perceive the vibration that we call sound. And those local areas can go off and get out of order, can get out of balance. If you take a person and keep him in a soundproof room long enough, that's a trouble I can do."
She lays out the field framing:
This framing has a curious consequence for how Ida thought about sensory deprivation and sensory development. If the field feeds the organ, then the organ requires its field. Take away light, and the eye fails. Take away sound, and the ear fails. The implication runs in the other direction too: the work of Structural Integration, by reorganizing the body within the gravitational field, presumably also alters what the body extracts from that field. The improvements in sight her clients reported during the first hour — sudden clarity, ability to see corners and ceilings — sit inside this larger conjecture. Some field-coupling has shifted, and the visual organ is suddenly receiving more of what it is structurally designed to receive.
The sensory-motor frame in Valerie Hunt's research
Ida's evolutionary reading and her cervical-plexi conjecture were not the only sensory discussions happening in her classes during these years. Valerie Hunt, the UCLA neurophysiologist who began studying the work in the early 1970s, contributed a parallel and more technically grounded account of how perception and motor function interlock. In a 1971-72 IPR session, Hunt sketches a sensory-motor theory of perception in which the way an individual organizes himself in relation to sensory input — by making both sensory adjustments and effector motor adjustments — is the way he experiences himself in his environment. The framework is dialogic with Ida's: it treats sensation and motor activity as a single coupled system, which is precisely the system Structural Integration is intervening in.
"And the model is a model of perception, and a model of perception and motor activity. And a model that says that the way an individual organizes himself in relation to sensory input by making certain kinds of sensory adjustments as well as effector motor adjustments, that's the way he experiences himself in his environment and that's the way he understands his world. So we start from a sensory motor theory of perception and try and hook up to a more clinical notion of what structural integration does. But it's a very simple general model. It says each of us, by the way he orients himself to his environment, takes an input and makes certain effector adjustments, that's the way he understands himself and his environment. So it's kind of a global statement about a man in relation to what's coming in to him and what's going on inside him. And from there we start talking about parameters or dimensions of sensory motor adjustment."
Hunt lays out the sensory-motor frame she brought to her UCLA studies of the work:
Hunt's frame matters because it specifies what the practitioner is changing. If perception and motor activity are a single coupled system, then changing the body's tissue is changing both at once. The sensory adjustments a person makes are constrained by the motor patterns available; the motor patterns are shaped by the sensory information that gets through. Hunt and her colleague Bob Stebbins (the pain researcher whose 1973 Big Sur lecture is preserved on tape) both argued that each individual has characteristic limits on the stimulus range to which he responds — and those limits are themselves a feature of the body's organization.
"And that happens anywhere from the gross psychological level, taking in information that sounds or visual stimuli to the kinds of sensory adjustments that occur in muscle and things that you ought to be knowing about dysprenata. Okay, so there are certain assumptions that have guided me in whatever emphasis the work that I do. One, that the nervous system has properties that serve to make order out of interoceptiveextraceptive stimulation. That these properties, these qualities of organization, define the limits of the stimulus range to which individuals respond. So you have to know the limits of what the organism is capable of doing with the information. What kind of information does he actually receive and what kind of information that is available in the environment doesn't come in at all. And this has relevance to a lot of the things that happen when we are talking about things."
Stebbins names the assumption that organizes his sensory work:
The convergence between Stebbins's pain research, Hunt's neurophysiology, and Ida's evolutionary reading is striking. All three are saying, in different idioms, that the sensorium is constructed and limited. Stebbins says it as a research assumption: information that does not pass the nervous system's filters does not exist for the organism. Hunt says it as a sensory-motor coupling: the body's organization determines what it can sense and what it can do. Ida says it through the evolutionary reading: the brain builds a model of a possible world, and that model is the inheritance of specific ecological pressures on the lineage. Three voices, one position.
Body image as the cumulative sensory record
The fourth voice in this conversation belongs to Valerie Hunt's collaborator on the educational and developmental side — the colleague who, in the 1974 Open Universe classes, laid out a theory of body image as the integrated record of the body's sensory experiences. The argument she makes is that body image is built from the memory of sensory experiences with the body, integrated into a gestalt, and then retained in the sensorium as the basis for the selection of all subsequent experience. This is a sensory-evolutionary claim at the individual level: just as the species' sensory apparatus is the residue of ecological pressures, the individual's body image is the residue of personal sensory history.
"The memory of the experiences we've had with the body integrated into a Gestalt which became an image and which we retained in our sensorium as the basis for the selection of all other experience. I want to say that again because I said a whole mouthful all kind of rumbled around. We have a body image and that image is the product of experiences we've had with our body through our five senses and these become integrated into a whole thing and we carry that body image around with it with us. It may be one of the most destructive things we ever learned is our body image one of the most deprecating and destructive things that we have. But we have to have it because it integrates all of these selves. It provides an attitudinal framework for responding so that in education if we provide an experience for children or for people in which they are going to respond in some way and we think this is going to be an enlightening experience the response is very highly based upon what is the body image like that they take into the experience. We know the perceptions and attitudes and feelings about this physical body are all incorporated. It's a very very profound sort of thing we're playing with."
She describes body image as the integrated memory of sensory experiences:
The same speaker, in a later session, gives a striking developmental anecdote that illustrates how thoroughly sensory deprivation deforms development — and how powerful sensory contact can be in restoring it. She describes work with severely under-stimulated children in a small playpen, where the sheer impossibility of avoiding each other's bodies — being stepped on, screamed at directly in the ear — restored basic motor and social functions in children who had never moved. The body image, she suggests, was built by being touched, by touching, by collision. It is the developmental version of the evolutionary argument: senses are world-builders, and without sensory contact the world fails to be built.
"And some of those children that had never moved if they were lying down there and somebody stepped right in the middle of their stomach they moved. They had the highest level of motivation on a very basic reflex level that you can possibly imagine. They took off. They took off. They touched each other with the hands. Of course they first touched face and they developed a body image. We had speech come to children in that playpen, a playpen with nothing in it except one square foot of space that you could hardly use because every time you used it you ran into somebody else. But it was that running into somebody else that developed a body image for these youngsters. Speech came, social development came, motor development came, it's being widely used throughout the country now I understand."
She describes the playpen work:
The eyes and spatial orientation in the work itself
The most direct point of contact between Ida's sensory thinking and the practical work emerges in a 1976 Teachers' Class discussion of how the eyes track and confirm postural change. The senior practitioner speaking — one of the teachers Ida had trained — observes that the eyes are one of the most important indicators of where a person is in space. A client may have just been brought, structurally, to a new vertical relationship; but if his eyes are still calibrated to his old height and his old fore-aft position, his visual system will pull him back to where it knows he belongs. The practitioner has to give the client permission to let the eyes recalibrate, sometimes by closing them while finding the new orientation.
"So this is why it's so important to look at where you're cuing a person at the end of an hour because they have a recording which let me add another thing for you to think about. The eyes to me are one of the most important indicators of where a person is in space. If they walk into the room and this is vertical to them where my eye level is, you may work on them and they have the capacity to be there. But their eyes tell them in the height of the room that, one, they are only this high when they stand upright, and two, they are back here, and you take them here, that's a whole new orientation. So you've got to tell them it's all right to let their eyes play tricks on them just for a moment until they take that space or maybe ask them to close their eyes while you help them find that. Ask them to open their eyes and then, you know, take a sense of where they are. I cannot tell you how often happens. It's the eyes."
She names the eyes as the spatial orienter that has to be reprogrammed:
This is the practical payoff of the encephalization reading. The retina's spatial code, which Ida had been emphasizing in the Teachers' Class, is also the spatial code by which the client locates himself in the room. Change the body and you have to allow the spatial code to update; otherwise the body's old map drags it back. The neck and the cervical plexi, the eyes and their spatial encoding, the vestibular apparatus in the inner ear — all of these are at the junction where Ida's evolutionary reading meets the question of how the work consolidates.
"acceleration sensors in the middle ear and the obelids, you know, and your head orientation too. They're full awareness of where we are in the gravity field. We're not the whole but large part. It comes from those that they're functioning. They they give us different messages depending on how our head is oriented. Well, now you're talking out of the book. I'm talking to you as Ralph's."
Another senior practitioner names the acceleration sensors in the inner ear and otoliths:
The autonomic as the senior nervous system
One thread runs through everything in this article: Ida's repeated insistence that the autonomic nervous system is the older nervous system, and that the senses, in their primary energy supply, are tied to the autonomic. She returns to this point in the 1975 Boulder advanced class with unusual force. In that class she draws the historical distinction between the autonomic — which evolved when survival demands were slow and the organism's main interest was endurance — and the central nervous system, which developed when the species needed to outrun a spear. The senses, she implies, predate the central system; they sit in the older layer.
"It's the newer system. It not only is the newer system, but the nervous system is not under the control of a muscular system ever. The nervous system is in control of the muscular system. But this is the answer, you see. The autonomic system is the old nervous system, and it is in charge, more or less, of unconscious processes. Now some of you probably know that there has been a great deal of work done in the last ten years demonstrating that you can get to the autonomic system through the central nervous system. You can get to involuntary functioning through voluntary desire and control. And this is important, but it's not important to us at this minute. At this minute, what I want you to clearly understand is that there are these two reasonably distinct nervous systems in the body and that they are in charge of different functions, different levels of functioning. That they connect back and forth. I mean there are strands from the central nervous system that feed into the plexus. So that they are not discrete. But in order to have a good functioning body, both those systems have to be organized and working and growing and alive and aware."
She draws the historical distinction between the two nervous systems:
The frame gives the practitioner a working orientation. The senses sit on the older nervous system; the cervical plexi feed them; structural reorganization of the cervical region may alter the energy available to the sense organ. None of this is settled mechanism. But Ida's reading of the encephalization paper, her cervical-plexi conjecture about sight, and her insistence on the autonomic's seniority all point in the same direction. The sensory apparatus is old, layered, and intimately tied to the body's structural organization. The work, in changing the structure, is necessarily reaching into the sensory apparatus, whether or not the practitioner intends it.
Coda: an open frontier
Ida did not close this material into doctrine. She left it open, as a research field for the senior practitioners she was training in her last full years of teaching. The encephalization reading in the Teachers' Class is not summarized into a clean takeaway. The cervical-plexi-and-sight conjecture is offered as a possibility, not a method. Hunt's, Stebbins's, and her other colleagues' contributions are placed alongside her own without being subordinated. The whole topic — what the senses are, how they evolved, what the work might be doing to them — is held as an unfinished inquiry to be carried forward.
"That I'll be willing to predict that in twenty five years someone, some few of this group will have spent their time and their thinking and their energy to find out and that they will be on a way of finding out how to utilize this for those areas of perception. This is ahead. This is what you people the opportunity that you people have. Have. Okay. Do you want to look at these? If you don't want to look at these now, I'm giving you an assignment. And that assignment is to trace some of that stuff to investigate with great specificity and care where those cervical plexi are, To recognize that there are three of them, the superior, the medial, the middle, and what should be the lower, but it's now called the spallic, yeah, ganglion plus the remnants of that lower plexus. Find out where they are. Find out on your own name. Try to perceive it when you're working with people exactly. Trying to see where these things are. And when you get all through, realize that somehow you're in the middle of a miracle,"
She closes with the charge to the next generation:
What survives, then, from this strand of Ida's late teaching is not a doctrine about the senses but a framing. The senses are constructions, shaped over evolutionary time by ecological pressure and over individual time by sensory contact. The visual system encodes space cheaply, by anatomy; the auditory and olfactory systems pay for space with neural tissue inside the brain. The hominid line, weak in smell, built a substitute labeling system out of voice and language, which is why language has the plasticity of a sensory-integrative system rather than the rigidity of a prewired communication code. The autonomic nervous system, the older of the body's two nervous systems, feeds the sense organs through the cervical plexi. When the practitioner reorganizes the cervical region, something happens to perception that the standard ophthalmological story does not account for. None of this was settled in 1976. Ida wanted it carried forward, and she said so.
See also: See also: Valerie Hunt's account of UCLA electrophysiological findings on neuromuscular energy patterns after the work, and the related discussions of the aura and energy coherence in the 1974 Healing Arts conference (CFHA_03, CFHA_04) — adjacent to the sensory question but pursued through bioelectric measurement rather than evolutionary argument. CFHA_03 ▸CFHA_04 ▸
See also: See also: the Open Universe class material on body image as a developmental sensory construction (UNI_072, UNI_071) and the parallel discussion of attention and sensory direction in the 1973 Big Sur pain lecture (BSPAIN1) — both extend the sensory-evolutionary thread into developmental and clinical territory. UNI_071 ▸UNI_072 ▸BSPAIN1 ▸
See also: See also: the 1975 Boulder advanced class discussion (T1SB) in which a senior practitioner reframes the ten-session series as a continuous spectrum of pelvic realignment — useful background for how the senior teachers understood the sequence within which sensory shifts (including the first-hour reports of improved sight) were observed. T1SB ▸