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Language Assessment for Communication Disorders

by John Oller Jr.

This site designed and maintained by
Prof. Glenn Fulcher

@languagetesting.info

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This feature is designed to accompany the following book chapter about the special problems presented to language testers (and theoreticians as well as researchers in general) by communication disorders:

Oller, J. W., Jr. (2012). Language assessment for communication disorders. In G. Fulcher & F. Davidson (eds.), Routledge Handbook of Language Testing, (pp. 150 - 161). London & New York: Routledge.



Introduction

In this feature you will find video clips illustrating key points in the chapter cited above. In particular, the point is to provide firsthand experimental evidence for certain aspects of the neuroarchitecture of the human brain that are distinctly linked to what is now widely, though somewhat loosely, being called "pragmatic mapping." One of the points to be brought out is to provide a somewhat sharper and also more intelligible definition of that process. It is, arguably, as will be shown here, essential to language acquisition and use. Here we have in mind speech as the primary manifestation of language, but writing, manual signing (as used by Deaf communities all over the world), complex mathematical calculations, and every form of articulated sequences of complex acts (e.g., reading or writing a musical score) should also be kept in mind. All such highly abstract and articulated sign functions, it comes out, depend on a very peculiar arrangement of the architecture and logic of our brains. That architecture is most evident in the simplest of language processing tasks, such as naming an object, identifying a number, constructing a meaningful statement, reporting a complex sequence of events, or understanding the feelings and motives of other persons. All such acts, depend at their basis on the foundational ability to map an abstract symbol (or string of them) onto a logical object that may be as simple as a pineapple or as complex as the memory of a lost love.

Language at the Heart

Because linguistic and other forms of communication are perhaps the very most common aspects of our ordinary lives, we tend to take them for granted. However, when communication disorders arise, processes that may have been unnoticed for many years, or that may have seemed mundane and inconsequential just a few weeks, days, or even moments earlier, may suddenly take over center stage in a drama gone haywire.

For instance, a man sitting in a parking lot at the grocery store may suddenly realize that not only has his headache taken a turn for the worse but that he no longer knows the meaning of the road sign he was reading a moment earlier and is still looking at. The letters and words are still there, but the meaning has vanished. What has gone wrong? Or, to take another example, how is it that a person like Oliver Sacks, a distinguished neurologist and psychiatrist, is apt to mistake an image of himself in a glass door for a different person - one whom he politely greets only to discover after thinking a bit that he has just said "hello" to an unrecognized image of himself? Or, how can it be that he mistakes a different bearded man on the opposite side of a plate glass window for an image of himself? He becomes aware of his error because Dr. Sacks is preening his beard and the image merely stares back. Why does anyone have such difficulty recognizing faces, even his own?

In the chapter cited above, communication disorders are defined as "unexpectedly long-lasting, persistent, or recurrent difficulties that interfere with normal, successful, ordinary communication" (Oller, Oller, & Badon 2010: 5). As such they provide a natural experimental laboratory revealing many normally subconscious, hidden elements of ordinary linguistic and other forms of communication. When it comes to language assessment, disorders invariably present special challenges, and they often reveal things about normal communication processes that would otherwise remain undiscovered.

Pragmatic Mapping: Language Acquisition and Brain Architecture

For several decades, I have been intrigued by the process that I proposed to call pragmatic mapping (Oller, 1972, 1975). Since then, that phrase has been applied (Gamaroff, 2000; Gentner, 2003; Goldberg, 2003; Gundel & Hedberg, 2007; Narramore, 1985; Ward, 2004; and many other references could be cited) in a general way to the problem of figuring out what it is that we or a computer in any given bit of discourse or code may be talking about. Taking account of all the social and emotional aspects that the investigation of the study of pragmatics in general has brought with it, Duchan (2011) refers to a "pragmatics revolution 1975-2000" as one of the highlights of the 20th century.

At the basis of all pragmatic theory - including questions about personal identity, feelings about ourselves, others, representations, and the events of the world at large - is the sort of simple, appropriate, true relation that can be seen between a referring term and its valid uses to signify or refer to its logical object. It is obvious that conscious ability to express our feelings of love, compassion, fear, pleasure, pain, and the like are utterly dependent on our association of them with whatever logical object be it a person, place, state of affairs, action, or whatever may give rise to the emotion in us. For example, Dr. Michael Mosely's commentary on being horrified at being momentarily trapped in a cave, is dependent on his keen awareness of where he is, what he can and cannot move, and the terrifying realization that he might not be able to get out. Presumably, Dr. Mosely would not experience fear of being trapped in a closed space if he were, say, anesthetized or completely unaware of his predicament. The logical object of the feeling must be identified in order for the feeling to be consciously understood for what it is and for what it is about.

Sometimes, because of a brain injury, the feeling itself may be inaccessible as it appears to be for Dave who lost a critical part of his brain. In the attached video, we learn that Dave is a patient with damaged emotions, much like many of the individuals singled out for attention years earlier by Dr. Antonio Damasio at the University of Southern California. At the time of filming, Dave was a patient of one of Damasio's students at the Health Emotions Institute at the University of Wisconsin. According to Dave's own reading of himself after his loss, feelings he can no longer generate with reference to, say, the love of his life, he fears will be lost to him entirely once he can no longer remember what they were like before his brain tumor surgery.

With all the foregoing in mind, to illustrate the nature of the foundational pragmatic mapping process, consider the simple act of naming. For instance, suppose we correctly refer to Dr. Oliver Sacks (any other successful reference would do) - the bearded man in the first video clip in this feature, a person who identifies himself as Oliver Sacks - by using the name "Oliver Sacks." Our use of that name, assuming that we have applied the name appropriately, consists of three component elements: (1) there is the name, "Oliver Sacks," an abstract conventional symbol, S; (2) in the video clip where he talks about his experience with faces, there is the moving picture of Oliver Sacks, an icon of the bodily person, Sacks himself, which is the logical object, O, of the act of naming (and of the camera pointed in such a way as to record his image, movements, and words); and (3) there is the pragmatic act, , an index, applying that name to the person who goes by it. The latter, , is a real indexical act of mapping the symbol S onto its logical O. The whole process results in a dynamic system of real relations that can be summed up in the triadic formula .

There are three distinct sign systems involved in every such pragmatic mapping triad. The dominant (rational) system of signs involved in every valid relation consists of the essentially linguistic part, the S. It comes out in research on brain functions, especially dating back to the pioneering work of Roger Sperry that won him a Nobel Prize in 1981, that producing speech, writing, or manual linguistic signs requires involvement of the dominant hemisphere of the brain. It is usually the left hemisphere. Sperry called it the "speaking hemisphere" and he could have added that it is also the writing hemisphere, the planning hemisphere, the calculating hemisphere, and in general the one that does articulated sequential planning and execution.

The process of pragmatic mapping may be relatively simple, as in an appropriate use of a name such as "Oliver Sacks," or it may be exceedingly complex, as in, say, reporting the whole of the still incomplete life history of Oliver Sacks. Regardless, these functions normally depend quite exclusively on work performed by the dominant hemisphere of our brains. The knowledge that the dominant hemisphere was critical to producing articulated sequences of linguistic forms pre-dates Sperry by 120 years going back to Paul Broca in 1861. However, it has become increasingly obvious over more than 13 decades since Broca published his findings about a man whose death was attributed to syphillis (but see the discussion in Oller, 2011) that more than just the left hemisphere, and a great deal more than "Broca's Area" is involved in sensible language production. The case of Julia Sedera, a trilingual management advisor, while recovering from a stroke is instructive.

The subordinated system of signs in every valid relation consists of the material part of that relation as manifested in the iconic representation of its O. In Julia's case, the O in one of the tests administered by Professor Cathy J. Price at the University College of London, Institute of Neurology, Julia cannot produce the word "pineapple" though she clearly recognizes the object to be named. She also cannot produce the word "envelope", though, again, she recognizes what it is and knows how it is used. Even when prompted by Professor Price with a syllable or two, Julia cannot say the words.

Julia's difficulty is focused on the motor production of the surface forms of the words involved in a simple naming operation. The material content, that is, the O, of the relation is accessible to her. She knows the O through her senses (seeing, hearing, touching, tasting, smelling). It is now well-known that the control of those sensory systems, as well as our ability to have feelings about the things, states of affairs, and sequences of events that we experience, is largely the province of the subordinate hemisphere of our brains.

However, to carry out the mapping of the S onto its O, or to work as Julia was attempting to do, from the visible icon of a pineapple to the motor production of the surface form of the word "pineapple," requires coordination and cooperation between the two hemispheres. In between the S and the O there must be some indexical movement(s), , linking the dominant system of S signs to the subordinate system of O signs. Those indexical movements, which must be sequenced appropriately to give meaningful results, are generally under the motor control of the dominant hemisphere. We can demonstrate the fact that the dominant hemisphere slaves the motor movements under the control of the subordinate hemisphere by writing our name in large bold strokes, for instance, with the right hand while the left either follows the right producing roughly the same movements in parallel, or, we can mirror the movements of the dominant hand with the subordinate hand. In doing so, we see empirical evidence that the dominant hemisphere can bring the subordinate hemisphere completely under its control.

In normal pragmatic mapping, the dominant hemisphere gets information from the subordinate hemisphere about sensory (iconic) information. Ordinarily, the functions of mapping S to O and vice versa - S to O being essential to vesting of S with content, and O to S being essential to representation (and thus determining the nature) of O, e.g., being able to identify a given object as a pineapple - depend on communications between the hemispheres through the bundle of fibers connecting them which is known as the corpus callosum.

From the pragmatic mapping formula, , we can infer the normal dominance relations actually found in the neuroarchitecture of the human brain. S must logically be dominant and O must be subordinate. However, to coordinate the dynamic mapping relations - ones that are essential to all meaningful representations (as has been proved and as will be summarized in the section below titled One Hemisphere Must Be in Charge) - communication between the hemispheres is essential, and the linguistic hemisphere, as Sperry discovered in his research with "split-brain" patients, is normally dominant. The neuroarchitecture can be spelled out roughly as shown in Diagram 1.

Diagram 1

Also, the relation applies in much the same way to the corpus callosum where its anterior parts are generally devoted to symbol processes (linguistic) while its medial parts are indexical (motoric) and its posterior parts are iconic (sensory) as shown in Diagram 2. The underlying figure in Diagram 2 comes from Hofer and Frahm (2006 and is reproduced by permission from Hofer; also see Paul, et al., 2007; and Oller, 2010). The fibers colored in green emanating from the corpus callosum to the frontal regions of the brain are believed to handle symbolic information; those in light or dark blue motor functions; and those in red, orange, yellow, and purple involve sensory functions.

Diagram 2

One Hemisphere Must Be in Charge

By far, the most important of the sign systems for human beings that may be affected by disorders are the conventional symbols of language. Bearing in mind the pragmatic mapping process, from the split-brain research of Roger Perry and his successors, we can understand a good deal about ways in which we map linguistic forms onto persons, places, events, relations and complex sequences and arrangements of all these. Also we can understand why it is that different disorders follow from differential damage to the brain. The most revealing studies showing the surprising but logically necessary division of labor in the brain involve experiments where the corpus callosum has been severed.

When the articulated elements of language and its related abstract conceptual systems are significantly impaired, the resulting disorders are known as the aphasias. An example would be Julia Sedera, see the video above, who has trouble naming a pineapple or repeating the word when it is presented to her in totality. It is noteworthy that one of the central findings of the split-brain research with humans is the fact that the dominant hemisphere is the talker: Sperry called it "the speaking hemisphere" as contrasted with its "mute partner." In his Nobel lecture of 1981, Sperry described outcomes of the radical split-brain surgeries (where the corpus callosum is severed) as follows:

    Each brain half . . . appeared to have its own, largely separate, cognitive domain with its own private perceptual, learning and memory experiences, all of which were seemingly oblivious of corresponding events in the other hemisphere. . . . The speaking hemisphere [the dominant one] in these patients could tell us directly in its own words that it knew nothing of the inner experience involved in test performances correctly carried out by the mute partner hemisphere [the minor one] (retrieved February 12, 2011, from here).

Sensory dysfunctions mainly impact iconic sign systems. When the subordinate hemisphere is damaged, or when its communications with the dominant hemisphere through the corpus callosum (CC) are impaired owing to damage to the posterior region of the CC, various agnosias are the predicted result. An example would be the sort of prosopagnosia illustrated in the video featuring Dr. Oliver Sacks.

Movement systems involved in simple acts such as starting a car, striking a match, tying a shoe, buckling a belt, may also go awry in what are known as the apraxias. The latter may also involve breakdowns in articulated actions of speech, musical performances, and sequences of sounds, syllables, intonations, and so forth in speech or manual signing. An extreme form of such a disorder is what is known as alien hand syndrome. For instance, "While the left brain is intent on eating a meal with the right hand, the subordinate hemisphere may instruct the left hand to push the plate away (Oller, Oller, & Badon 2010: 270ff)." Here next is an extreme and tragic example of a split-brain surgery where the missing CC connections resulted in a dramatic war within the patient over which hemisphere would ultimately be in charge of ordinary actions.

The Logical Uniqueness of True Narrative Representations

What has occupied my own thinking the most in the last two decades has been the discovery and exposition of proofs that language acquisition utterly depends on access to complete relations as manifested in what may be termed true narrative representations (TNRs). Every valid relation is necessarily part of an unfolding narrative on account of the fact that real material objects can only be known and referred to in experience as it is manifested over time and in space. If the object referred to must be imagined, then, the S part of the representation introduces a fiction to be supplied by imagination, . But, if the S is requisite to the determinate representation of any particular fiction, the meaning of that S cannot be discovered from that fiction because the S in play is the only means of determining the fiction. If a fictional representation is mistaken for a TNR, the result is an error, , where the S is not what it should be, say, Oliver Sacks is mistaken for Noam Chomsky, and the bodily object, O, on hand, Sacks, is not the one named, Chomsky. But also, the name supplied, "Noam Chomsky," is not the one required, "Oliver Sacks." But to discover all this, a TNR of the shape, is required. In a still more confused instance, suppose a known error is deliberately represented as if it should be taken as a TNR: the result is a lie, , where all three sign elements are corrupted with the intention of deceiving someone else. But to uncover the errors underlying the lie, again, TNRs of the shape are required.

To get a more degenerate (but still meaningful) representation than a lie, we would have to resort to some form of nonsense where the difficulty of resolving any particular content (a purported meaning) ranges from minimal to a limit of the impossibility of assigning any particular meaning to complete chaos. With nonsense, it becomes increasingly impossible to assign a determinate meaning even for the nefarious purpose of deception. But nonsense of any sort can only be associated with any S to the extent that the nonsense itself resembles some conventional S, and yet, the resemblance to a meaningful S, ultimately leads us back to valid relations or to nothing at all. Thus, even nonsense depends utterly on TNRs.

Details aside, it has been proved logically by strict mathematical reasoning (Oller, 1996; Peirce, 1897; Tarski, 1936, 1944) that any material content whatever that might be associated with any fiction, error, lie, or even some bit of nonsense must have a basis in some prior well-formed TNR. From such mathematical proofs, it follows that language teaching and testing methods that richly incorporate well-formed TNRs ought to have, all else being equal, greater validity, reliability, and usefulness than ones relying on fictions, errors, lies, or nonsense. This result should hold even if the fictions, errors, lies, etc., are exactly similar in all respects except with respect to the actual material content of TNRs). In fact, empirical findings are very consistent with this expectation (Oller, Chen, Oller, & Pan, 2005; Oller, Oller, & Badon, 2006). The relatively greater difficulty of understanding the more marked instances of fictions, errors, lies, and nonsense, as contrasted with ordinary TNRs is perfectly consistent with the fact that children first master and are able to understand and produce TNRs (by about 12 months after birth), later fictions (by about age 2-3 years), then errors (by about 3-4 years), and lies by about 5-7 years. That is, normal children are able to correctly explain the difference between errors and lies by about 6 years of age. To explain why any bit of nonsense doesn't make sense, all else being equal, is more of a challenge, even for adults. The problem with nonsense, unlike fictions, errors, and lies, is that there is no determinate way whatever to convert complete nonsense into a sensible TNR.

Next, consider the fact that our ability to carry out, imagine, or report a sequence of actions is utterly dependent on articulate coordinations of complex pragmatic mapping operations. Say a certain person gets his hat and coat, checks to see that the car keys are in his right hand coat pocket, walks to his car, unlocks it, gets in and starts the car, and drives home after work. As pointed out in the paper linked to this feature: "Conceptualizing and executing such a sequence requires dominant hemisphere involvement as does reporting it after the fact. Carrying out, recalling, and reporting such a sequence also involves the subordinate hemisphere in obvious ways: distinguishing the articles of clothing, hat from coat, the keys from pocket change or a wallet, the right hand pocket from the left, the car from others parked nearby, the ignition key from others, and so forth. While all that is occurring, or being recalled and reported after the fact, a great deal of communication is occurring between the two hemispheres of the brain. . . ."

Episodic Organization and Syntactic Complexity

A ubiquitous requirement for articulated volitional movements is what has been called "episodic organization," "meaningful sequence" (Oller, Sr., 1963-1967; Oller, Chen, Oller, & Pan, 2005), and "serial ordering." Karl Lashley, one of Roger Sperry's teachers, commented on its importance in this way:

    The organization of language seems to me to be characteristic of almost all other cerebral activity. There is a series of hierarchies of organization: the order of vocal movements in pronouncing the word, the order of words in the sentence, the order of sentences in the paragraph, the rational order of paragraphs in a discourse. Not only speech, but all skilled acts seem to involve the same problems of serial ordering, even down to the temporal coordinations of muscular contradictions in such a movement as reaching and grasping (1951: p. 187).

It is not difficult to find disorders of the central nervous systems in which the normal sequential control systems break down. In Parkinson's disease and cerebral palsy, the problem of reaching and grasping an object of interest may present extreme difficulty (Oller, Oller, & Badon 2010: 270ff). However, it has been shown in the single dramatic case of Henry Gustav Molaison (born February 26, 1926, died December 2, 2008) that a certain portion of the brain, notably the hippocampus, is critical to the formation of the sort of episodic memories that enable us to recall and report a sequence of events. At the age of 27 he was operated on by Dr. William Beecher Scoville who, in an attempt to alleviate Henry's epileptic seizures, removed parts of his temporal lobes in both hemispheres and virtually destroyed (two-thirds of it being removed) Henry's hippocampus. For the alleviation of seizures, the cost was high.

The effect on Henry was devastating to his ability to form new episodic memories, but left intact, at least some of his ability to form motoric memories beneath a conscious level as is illustrated in this segment of video describing an experimental task presented and demonstrated to Dr. Michael Mosely interacting with Professor Elizabeth Kensinger at MIT, one of the last researchers to work with Henry Moliason before his death. The critical experiment, at the end of the segment, shows that Henry could improve his ability to perform an unfamiliar motor task with practice but that he remained unable to recall and report on any of the various practice sessions resulting in his improved performance.

To realize the extent to which conscious access to actual sequences of events in experience depends on both hemispheres of the brain as well as the crucial involvement of the hippocampus is profoundly important to understanding how we develop our sense of personal identity. That notion of self is, normally, grounded in a history of connected experiences that are uniquely associated with our bodily presence in space and over time. When the connections in those experiences are disrupted, as was done in the case of Henry Molaison, or when the memories themselves become less and less accessible, as with progressive Alzheimer's, a person may lose much more than the ability to recognize his or her loved ones, or even himself in a mirror (as in prosopagnosia). It is possible to lose even the memory of self. As Dave suggested concerning his inability to generate feelings associated with events in his experience, the fear that when the memories of one's past are completely gone, the self once known vanishes with the memories.

Setting to one side the unpleasant conclusion that disorders are generally not desirable, there is one more step to be taken in completing the mathematical demonstration (a strict proof) that all episodic representations, i.e., all narratives and narrative based systems of representation, depend for their meaning on the simplest of relations - to be precise, the sort illustrated in a valid act of naming. From the strictest of mathematical logic it follows that if an abstract predicate referring to any act, state, or quality of any given logical object or plurality of them remains completely unattached to the material world of common experience, it must also be unintelligible and without any determinate meaning. Therefore, as syntactic complexity advances in language acquisition from the noticing actual states and events in the here and now, to imagined possibilities, contrary to fact conditionals, and right on up to all of the complexities attainable through abstraction and recombination every step up through the vast hierarchy of sign systems depends for its meaningfulness on building blocks that being with simple acts of referring as summed up in the formula. Think what "Dancing with the Stars" would be if there were no stars and no dancers and you can get a fairly practical idea of why pragmatic mapping of the simplest sort, the kind where children begin to decipher complex human languages, is foundational to all of the higher and more complex syntactic constructions.

References

Broca, P. P. (1861). Perte de la parole; ramolissement chronique et destruction partielle du lobe anterieur gauche de cerveau. (Loss of speech: Chronic softening and partial destruction of the left frontal lobe of the brain.) Bulletins de la Societe d'Anthropologie de Paris, 2, 235-238.

Duchan, J. (2011) The Pragmatics Revolution 1975-2000, retrieved February 11, 2011, from Download here.

Gamaroff, R. (2000). Rater reliability in language assessment: The bug of all bears. System, 28, 31-53.

Gentner, D. (2003). Analogical reasoning, psychology of. In Encyclopedia of Cognitive Science (Vol 1, pp. 106-112). London: Nature Publishing Group.

Goldberg A. E. (2006) Constructions at work: The nature of generalization in language. Oxford and New York: Oxford University Press.

Goldberg, A. E. (2008). Universal Grammar? Or prerequisites for natural language? Behavioral and Brain Sciences, 31, 522-523. doi:10.1017/S0140525X0800513X

Gundel, J. K., & Hedberg, N. (Eds.) (2007). Reference: Interdisciplinary perspectives. New York, NY: Oxford University Press.

Hofer, S., & Frahm, J. (2006). Topography of the human corpus callosum revisited-Comprehensive fiber tractography using diffusion tensor magnetic resonance imaging. Neuroimage, 32, 989-994. Figure 1; Panel A.

Lashley, K. (1951). The problem of serial order in behavior. In Jeffress, L. A., ed., Cerebral Mechanisms in Behavior. New York: Wiley, pp. 112-136. Reprinted in S. Saporta, ed., 1961. Psycholinguistics. New York: Holt, pp. 180-197.

Narramore, R. C. (1985). Explorations of language use: Pragmatic mapping in L1 and L2. Topics in Language Disorders, 5(4), 66-79. Download here

Oller, J. W., Jr. (1972). On the relation between syntax, semantics and pragmatics. Linguistics: An International Review, 83, 43-54.

Oller, J. W., Jr. (1975). Pragmatic mappings. Lingua, 35, 333-344.

Oller, J. W., Jr. (2010). The antithesis of entropy: Biosemiotic communication from genetics to human language with special emphasis on the immune systems. Entropy, 12, 631-705. doi:10.3390/e1204063

Oller, J. W., Jr., Chen, L., Oller, S. D., and Pan, N. (2005). Empirical predictions from a general theory of signs. Discourse Processes, 40(2), 115-144.

Oller, J. W., Jr., Oller, S. D., & Badon, L. C. (2006). Milestones: Normal speech and language development across the life span. San Diego, CA: Plural Publishing, Inc.

Oller, J. W., Jr., Oller, S. D., & Badon, L. C. (2010). Cases: Introducing communication disorders across the life span. San Diego, CA: Plural Publishing, Inc.

Oller, J. W., Sr. (1963-1967). El espanol por el mundo. Chicago: Encyclopedia Britannica Films, Inc.

Paul, L.K., Brown, W.S., Adolphs, R., Tyszka, J.M., Richards, L.J., Mukherjee, P., & Sherr, E.H. (2007). Agenesis of the corpus callosum: Genetic, developmental and functional aspects of connectivity. National Review of Neuroscience, 8, 287-299.

Peirce, C. S. (1897). The logic of relatives. The Monist, 7, 161-217; also in C. Hartshorne & P. Weiss (Eds.), (1933), Collected papers of C. S. Peirce, Volume 3 (pp. 288-345). Cambridge, MA: Harvard University Press.

Sperry, R. W. (1981). Nobel lecture: Some effects of disconnecting the cerebral hemispheres. Retrieved September 25, 2008, from Download here.

Tarski, A. (1949). The semantic conception of truth. In H. Feigl & W. Sellars (Eds. and Trans.), Readings in philosophical analysis (pp. 341-374). New York: Appleton. (Original work published 1944)

Tarski, A. (1956). The concept of truth in formalized languages. In J. J. Woodger (Ed. and Trans.), Logic, semantics, and metamathematics (pp. 152-278). Oxford: Oxford University. (Original work published 1936)

Ward, G. L. (2004). Equatives and deferred reference. Language, 80(2), 262-289.


John Oller Jr.
June 2011