One-Handed Simplified Signs 1. Memory and Recall of One-Handed Signs: The Development of a Simplified Sign System for Aphasic Patients with Hemiplegia

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1 One-Handed Simplified Signs 1 Memory and Recall of One-Handed Signs: The Development of a Simplified Sign System for Aphasic Patients with Hemiplegia Alexandria K. Moore Distinguished Majors Thesis University of Virginia April 25, 2011 Advisor: John D. Bonvillian Second Reader: Filip Loncke

2 One-Handed Simplified Signs 2 Abstract A one-handed simplified sign system is proposed to augment the communication skills of persons who have become aphasic and who also experience partial motor movement loss. Based on a previously developed two-handed system, manual signs were modified or created. The memorability of those signs was established through systematic testing of undergraduate students. These signs were presented together with their English translations in sets of six lists of twenty word-sign pairs. Following the presentation of each list, participants were asked to recall each sign after they were cued for recall with each sign s English translation equivalent. Sign recall accuracy was evaluated based on the four components of each sign: movement, location, handshape and orientation. All signs recalled perfectly by at least 70% of the participants were added to the simplified sign lexicon. Signs that did not meet this criterion were redesigned.

3 One-Handed Simplified Signs 3 Acknowledgment I would like to extend a heartfelt thanks to Professor John Bonvillian for the generous amount of time he put into advising on this project. Without his continued support and enthusiasm completing this DMP would not have been possible. I would like to thank my second reader, Filip Loncke, and the DMP seminar leader, Gerald Clore, for taking time to assist me with this project. Additionally, I would like to thank my four fantastic undergraduate research assistants, Brigette Suijk, Katherine Becker, Kelly Flynn, and Kira Bolton for all of their time, ideas, patience and hard work. Thanks also are extended to Henry Matthews for his work on redesigning signs that have not met criteria. I would like to thank all of my friends and family who have always been so supportive, and specifically for allowing me to put their charades skills to the test.

4 One-Handed Simplified Signs 4 Roughly one hundred thousand new patients are diagnosed with aphasias annually, part of the one million who already suffer from this language disorder. i Several different types of aphasia exist, each having specific identifying characteristics in conjunction with a wide array of individual differences, but all reflect a disorder that impairs traditional spoken (or written) language despite other intact intellectual capabilities. This language deficit, typically caused by damage to the left hemisphere resulting from trauma such as stroke, tumor or other injury, does provide a unique opportunity for researchers to study how specific brain areas relate to language use. One aspect of aphasia research that has greatly impacted the psycholinguistic field involves studying Deaf patients who used a signed language as their primary means of communication prior to suffering trauma. After research in the last fifty years provided strong linguistic evidence that American Sign Language included all the components of a grammatically and syntactically rich language, researchers questioned if the different modality required different underlying brain areas to function. Studies that compare Deaf signers who develop aphasia to hearing aphasic patients with aphasia allow researchers to examine how similar deficits affect language output despite the difference between a verbal and signed mode of communication. The results surprised many, revealing that Deaf people show similar errors and deficits as their hearing counterparts, providing evidence to support at least partially overlapping mechanical structure for language output across modalities. While many similar deficits have been found, one interesting distinction existed in terms of less common right hemisphere deficits. This side of the brain has fewer associations with language in hearing patients, but contributes more to

5 One-Handed Simplified Signs 5 language production in Deaf patients, because the grammar of sign language depends on spatial abilities. This difference may be the key to developing a treatment method that, while not able to cure the aphasia, could provide the patient with a basic supplemental or alternative form of communication. Several studies have tested the effectiveness of using signs to help aphasiac patients regain some form of effective communication. While the results of these studies have been promising, many researchers concur that a feasible system, involving iconic, easy to produce gestures should be designed and tested. Thus this research proves important not only for studying how areas of the brain support language but providing at least some members of a large group of affected aphasic patients an opportunity to regain a critically important human skill, the ability to communicate effectively with others. In this paper I will begin by providing background information about aphasia that will provide details about the affected population and the constraints persons with aphasia face when considering treatment options. Subsequently, I will highlight some major research studies using aphasic patients with language deficits. Studies of aphasia such as these investigations suggest possible approaches to treatment. One potential treatment method that seems feasible based on these studies involves utilizing gestural communication to help facilitate or supplement spoken language skills; there has been some prior research examining the effectiveness of this course of action. However, as will become apparent from reviews of other studies, no gestural based system currently available adequately meets the needs of the aphasic population because the systems were not designed or tailored to the needs of this group. The present study aims to take the first

6 One-Handed Simplified Signs 6 steps in creating such a communication system, one that features one-handed signs with the most basic handshapes and movements representing a core vocabulary of words. Understanding Aphasia According to the National Aphasia Association, between twenty-five and forty percent of stroke survivors will develop an aphasia. ii This high percentage rate, coupled with the increased survivability because of improved medical care, explains why strokes are the leading cause of aphasia. This also reveals why elderly patients form the majority of aphasics, because nearly three quarters of stroke victims are over sixty-five years old. iii Brain tumors provide another internal source of aphasias, if the tumors are located in and damaged the left hemisphere. External trauma may also cause this language defect. Car accidents or even falling affect people of all ages and can also lead to aphasia. Another example of a specific population potentially affected with this condition includes members of the military who suffer injuries caused by explosions, shrapnel and similar hazards that they might encounter in a war zone. With the United States actively engaged in conflicts overseas, the number of people at risk for this language disorder rises. Psychologists, linguists, speech therapists and other specialists aim to help all of these different groups regain their communicative abilities regardless of the source of the damage. Initially, some of these researchers used imaging studies to enrich the scientific community s understanding of the underlying brain structures that support language with great success and exciting results. In recent years the primary focus in this body of research shifted to testing different methods of improving the patients communication skills. With intellectual capabilities intact, not being able to express basic wants and needs leads to obvious frustrations and even depression in some patients. Since language

7 One-Handed Simplified Signs 7 defines most human interaction, helping these patients regain that critical ability underscores the importance of this area of research. While some patients will make a recovery, if quick progress in regaining normal language capabilities does not occur the resulting damage will likely become permanent and alternative communication systems become more important. A wide array of individual differences, depending on the location and extent of the injury, causes the deficits to range from jumbled speech to a total lack of understandable communication. There are several types of aphasia, all resulting in various impairments of language output. There have been dozens of ways to describe different types of aphasia, but the National Institute of Health s National Institute on Deafness and Other Communication Disorders offers these guidelines for a general aphasia diagnosis: The examination includes the person s ability to speak, express ideas, converse socially, understand language, read, and write, as well as the ability to swallow and to use alternative and augmentative communication. iv From this general definition, further study of the specific types of deficits and language errors a particular patient displays would indicate the type of aphasia. The three most often observed aphasias include Broca s aphasia, Wernicke s aphasia and global aphasia. The first two types, named after the areas of the brain predominantly damaged, show nearly opposite language issues. Broca s aphasic patients generally use words in an understandable order, but tend to rely solely on nouns and verbs. Their speech is characterized by long pauses, and an apparent struggle to come up with the correct word. In contrast, Wernicke s aphasic patients appear to have grammatically fluid speech, but closer inspection reveals the unintelligibility of the content. Both of these aphasias derive from damage to very

8 One-Handed Simplified Signs 8 specific areas in the brain that then provides the name for the aphasia. Global aphasia occurs with the destruction of a larger area of the left hemisphere. The extent of the damage corresponds to severe problems with language production. Most patients have little to no spoken or written language, and comprehension seems equally devastated. In addition to all the variations among aphasia types, a wide variety of individual differences exist reflecting the fact that the damage each patient suffers differs. Even within types, patients will show variation in their language capabilities. This might impact the decision to use a particular treatment over another to most benefit a specific patient, reflecting their individual capabilities and deficits. Additionally, besides language impairment, aphasias often co-occur with weakness or paralysis of the extremities, typically those on the right side of the body. This condition, known as hemiplegia, does not occur in all aphasic patients, but happens enough to make it an important limitation to consider when assessing possible augmentative or alternative communication systems for a patient. Aphasia Patients and Deficit Studies Before addressing possible treatments for aphasic patients, I will explore some of the literature on how the study of aphasic patients has greatly contributed to our understanding of language, particularly signed language in comparison with its spoken counterpart. Deficit studies have often played a prominent role in mapping the functions of different areas of the brain, and the study of language particularly benefits from these unfortunate accidents. This particular type of research occurs when someone sustains a brain injury and then researchers subsequently determine the specific areas damaged and

9 One-Handed Simplified Signs 9 the nature of the resulting impairment. For example in studies of language deficits, comparing the grammatical, syntactical, phonological and semantic aspects of a patient s language production with that of someone without any brain injuries might suggest that a certain area of the brain contributes to that specific component of language output. More specifically, this section will address studies focused on sign language with the dual goals of identifying which brain structures contribute to signed language and the similarities and differences between the areas used in verbal and signed communication. These studies support relatively recent claims that signed language meets the requirements of a full and rich language by using many of the same areas of the brain as spoken languages. The differences in brain structure use might suggest a way for patients who have lost their traditional verbal language skills to regain communication via a different language modality. Before examining how deficit studies might suggest a treatment for aphasic patients through the brain s differences in processing signed languages, it is important to establish the similarities with its verbal counterpart. It has been widely recognized that damage to the left hemisphere greatly impacts verbal language output. Only recently has interest in signed language prompted scientists to attempt to determine if the effects are similar for a Deaf person who used signed language as their primary or only means of communication. Finding someone who was both a native signer and suffered from a relatively uncommon brain lesion proved to be a challenge in the conduct of these studies, however, because very few people would fall into both categories. In some ways, the case studies that have been carried out meet expectations by showing a similar pattern of language damage in Deaf aphasics as compared with spoken

10 One-Handed Simplified Signs 10 language users. For example, in a recent study, a man who had been Deaf since infancy and a fluent user of Japanese Sign Language suffered a left occipital lobe lesion and experienced sign language aphasia (Saito, Otuski, & Ueno, 2007). As a result of his injury, the man could follow a few very basic signs, but lost all ability to fingerspell, a technique found in sign languages around the world where each letter in the alphabet corresponds to a handshape and these handshapes are then signed in sequence to spell a word that does not have a traditional sign, such as a proper noun. Like hearing aphasics, this patient s ability to comprehend written words also suffered. He could not correctly read a sentence that he had written down himself. His sign production included manual phonological errors that mimic those that occur in the spoken language counterpart. Verbally, patients might substitute one phoneme they hear for a similar one while this patient would often mistake similar looking handshapes. This supports the argument that damage to the left hemisphere affects signers and speakers of oral languages in similar ways and that the brain structures in that area support language regardless of modality. The authors of the study did note some obvious structural differences in this case study, primarily the fact that this man s damage occurred in the occipital lobe. The study acknowledges that while sign language does appear to rely on many language structures shared across modalities, signed language is an inherently visual language and thus does involve some different areas of the brain. In this particular instance, damage to the occipital region was seen as being critical to signed language in the same way a lesion to the auditory cortex would impact a hearing person s language. This finding supports an earlier literature review published in 2000 that provides a broad overview of these types of deficit studies and addresses not only the similarity in

11 One-Handed Simplified Signs 11 structural function but also the importance of the differences in right hemisphere use in signers versus hearing people. Ronberg, Soderfeldt and Risberg (2000) described signers whose aphasic symptoms match those demonstrated in hearing patients diagnosed with Broca s or Wernicke s aphasia. For example, posterior left-hemisphere lesions led to fluent looking signs but with issues in sentence comprehension and sign recognition. Essentially the syntactical structure seemed to be intact but the content of the sentences made no sense, as is typical for a person with a Wernicke s aphasia. Signers with anterior left hemisphere brain damage had non-fluent production, characteristic of the short, choppy sentences of Broca s aphasia, and few comprehension problems. While these findings do support the critical structural connection between spoken and signed languages, the Ronberg et al. review goes on to emphasize the structural differences between the two languages. As noted in the Saito et al. article, signed language depends on visual rather than auditory input, and some different brain structures must be used to process this information. The ways in which the right-hemisphere contributes to signed language comprehension are still being studied. One documented phenomenon includes differing patterns of right hemisphere activation between signers and speakers. In people who use signing as their mode of communication, homologous areas of the brain are activated on the left and right side, while spoken language users show a distinct proclivity for the left hemisphere alone. Additional difference in brain activity demonstrated that signers process language input differently from other gestural or spatial input in the right hemisphere. One case study reviewed in the Ronberg et al. article describes a Deaf patient with a right-hemisphere lesion that resulted in radically impaired artistic non-language skills but had no impact on her ability to use American

12 One-Handed Simplified Signs 12 Sign Language. As this case study and others reveal, the spatial cues such as mapping and complex perspective taking inherent in signed language impact the use and strength of various brain areas, owing to neural plasticity (though without precise neuroimaging, the brain areas involved in language use both before and after the trauma cannot be pinpointed). These strengthened right hemispheres in signers allow for some of their native linguistic components to remain intact even when other non-linguistic spatial components or the left hemisphere is damaged. The authors suggest that this new understanding of the right hemispheres capacity for some aspects of language might point to a potential treatment for the more typical hearing aphasic patients. A group of British researchers have furthered these claims and focused particular attention on Deaf aphasics by distinguishing between signs and gestures, as well as by using sign to cue a spoken language (Marshall, Atkinson, Woll, & Thacker, 2005). As the title suggests, Aphasia in a user of British Sign Language: Dissociation between sign and gesture details one aphasic patient s ability to understand non-linguistic gestures but not signs. It would seem plausible that gestures and signs would be processed in the brain in the same way because they are both visual, uses the hands, and contain movement to communicate some type of information, however rudimentary. This study features a Deaf man with a clear case of anomia, a deficit in word retrieval (also found in hearing patients). Despite suffering from a severe aphasia, his ability to understand and repeat nonverbal gestures was intact. Regardless, the brain damage he sustained made it impossible for him to produce a particular sign when prompted, even if he could easily imitate a very similar gesture. Despite their apparent similarities, gestures and signs

13 One-Handed Simplified Signs 13 register in the brain differently, which might impact the possible types of treatments considered for persons with aphasia. The most illuminating deficit study, in terms of its clear implications for possible treatment, also comes from Marshall and her colleagues. She and her fellow researchers located a Deaf woman who knew English in addition to British Signed Language (Marshall, Atkinson, Smulovitch, Thacker, & Woll, 2004). Like previous case studies, this woman developed her aphasia after suffering a left hemisphere trauma. As a result, she essentially lost her capability to understand both languages suggesting a shared central area for semantic processing. Despite the severity of her language loss, the researchers found one promising area, not for recovery, but for re-establishing some kind of minimal language use. The study found that if she was cued with a BSL sign then she could be prompted to say an English word. This did not apply if nonverbal gestures replaced BSL signs as the cue. Despite the fact that the cuing findings only applied to nouns, this opens up a new approach for improving aphasics language abilities. As I will discuss in the following section on treatment studies, a major concern with using signed language to help patients communicate is the fear that doing so would eliminate any chance of spoken language recovery. This study demonstrates that in fact the two different languages, when used in conjunction, may actually help improve language skills rather then hinder them in a particular modality. All of the above deficit studies do have limitations that should be addressed when considering the implications of their findings, despite being a commonly used research method. First, the majority of these studies follow only a single participant. They feature a case study format that does not meet the requirements of an experimental design;

14 One-Handed Simplified Signs 14 therefore it is impossible to definitively say that brain damage to a certain area causes a certain type of deficit. Additionally, as a result of the individual differences between injuries, these studies are very difficult to replicate with precision. Most of the consensus across studies occurs when patients have injuries to the same general area of the brain, such as Broca s or Wernicke s. Yet the severity and exact boundary of the damaged area in the studies cannot be controlled. This makes the linking of a specific linguistic component with an equally specific area of the brain very difficult, if not impossible. Gestural Communication as a Treatment for Aphasia As mentioned earlier, if rapid improvement over a matter of weeks in impaired language faculties does not begin soon after the brain damage occurs, then the chances for making a full recovery decrease dramatically. In the weeks and months following the initial diagnosis, patients typically begin courses of treatment focused specifically on regaining verbal communications. Unfortunately, some of these programs have seen very limited success. Despite these setbacks, scientists continue to look for methods to assist patients in regaining some type of communication skills. The findings from deficit studies of Deaf aphasics, such as the ones covered in the previous section, suggest a possible avenue for treatment. A change in communication modality may enable some persons with aphasia to use unimpaired areas of their left hemisphere. Moreover, as stated before, the right hemisphere plays a more robust role in the processing of signed languages than in oral languages. Patients that have severely damaged left hemispheres may be able to access at least some of the components of languages by tapping into the modality favored in the other hemisphere. This means

15 One-Handed Simplified Signs 15 using some form of gestural communication, with its visuospatial orientation. The literature does not suggest teaching patients formal American Sign Language, or its equivalents, because the grammatical complexities would require more support than the damaged resources of the left hemisphere could provide. However, any form of communication, regardless of how limited in scope and normal fluency, could improve the quality of life for patients with no or few alternatives. The focus of this area of research includes establishing gestural communication as a possible treatment course and then specifically what type of system would be most appropriate to teach to patients. The initial results from research using signed language with aphasic patients looks promising, and E. James Moody s (1982) article Sign language acquisition by a global aphasic explores possible reasons why signs may be effective, as well as noting the drawbacks to this approach. Global aphasics typically have the most severe and widespread trauma of aphasic patients and, consequently, a grim prognosis for language recovery. Moody postulated that despite the severe damage to the left hemisphere, patients could understand words and make the connections necessary to use them through the right hemisphere even if they lacked the capability to express them verbally. To compensate for the inability to produce coherent verbal output, Moody suggested that a communication system consisting of gestures or signs might fill this gap. He offers several reasons why this approach proves more feasible than a verbal treatment. First, as already suggested, the brain areas, such as centers for processing visual input, remain intact and signs would utilize these areas whereas verbal communication could not. Second, teaching a patient how to use gestural communication would be much easier than trying to help them re-learn verbal communication, for several reasons. Signs have a

16 One-Handed Simplified Signs 16 longer production duration than spoken words, so for a patient who needs more time to process input, this may prove useful. In terms of the patient s sign production, a researcher or teacher can easily help shape the hand to form a sign correctly. Most verbal phonological sounds made by various positions of the mouth and tongue cannot be easily shaped with external help. Signs, some of which are one handed, could circumvent the oral apraxia typical of global aphasia that makes speaking difficult as well as largely avoiding any hemiplegia in one arm. Finally, while most signs do not represent their meaning, in these treatment scenarios iconic signs can be selected or created. These would be easier to learn and use, especially since the right hemisphere typically processes more concrete things. Moody put these ideas to use in a case study involving a global aphasic. The patient was exposed both to signs and speech in a Total Communication approach, which entails using verbal production and signs simultaneously. Not surprisingly, given the severity of the patient s injury, speech attempts failed. Moody did find, however, that the patient had some communicative success with a limited number of signs. For a global aphasic to regain any form of communicative ability marks a huge advancement, regardless of the limited scope of his or her signing. Despite the relative success, there were some notable limitations. Moody s patient acquired nouns better then verbs and had to avoid cognitively similar words, particularly if the signs looked similar. For example, the patient struggled with the signs for knife and spoon, cognitively similar in function and sign production. While the patient could correct some of his own mistakes, he still worked best when paired with a researcher speaking to him in order to prompt the signs.

17 One-Handed Simplified Signs 17 While Moody s results with a particularly severe case look promising, the issue of individual differences remains a problem. Another important early study not only consisted of an experiment testing gestural communication with a large number of participants for this type of research, but also looked at how the severity of the aphasia impacted the participants ability to use such an approach (Kelsch, Daniloff, Noll, Fristoe, & Lloyd, 1982). Fifteen aphasic patients were involved in this experiment, making it one of the largest studies of its kind. The experimenters divided the patients into three groups of five, based on the severity of their diagnosis. It should be noted, however, that even the highest functioning group did not include people with the most severe aphasic diagnosis. All of the patients suffered from unilateral left hemisphere cerebral damage: in most instances, this was caused by cerebral vascular accidents or strokes, though a few cases were caused by head trauma. Unlike most experiments in this field, this design did not use a spoken language component on the part of the experimenter or patient. Instead the researchers showed each patient a card with four simple line drawings on it in black and white in an effort to elicit a signed response. One of the images was the target, the image that the patient ideally recognized and then made the corresponding gesture, the second was a foil similar to but not the target, and two unrelated drawings. There were twenty-four cards, half depicting objects and half depicting actions. The selection of the images used related to the basic needs of patients, in order to produce attempts at relevant communication. The patients produced their response using gestures from American Indian Sign, also known as AmerInd, chosen because of its high proportion of iconic signs, which while not as extensive as

18 One-Handed Simplified Signs 18 initially thought, far outnumber the proportion of iconic signs in languages such as ASL (Daniloff, Lloyd, & Fristoe, 1983). The results from this study indicate that, within a certain range, the severity of the aphasia does not impact the patients ability to use the AmerInd signs. Rather then severity, factors such as the patients listening ability correlated substantially to the ability to produce more signs in the correct context. This suggests that, unlike previously thought, that even patients with moderate brain damage might benefit from this treatment approach. This experiment also excluded patients with the most severe impairments, so that this study provides little insight on the effectiveness of this type of approach with that specific population. Unlike the Moody study, Daniloff and her colleagues found that patients more easily identified action pictures than the object pictures. These results stand out in this body of research because most researchers find that nouns tend to be more memorable. A possible explanation for these results might be found in the study s design. This study used a recognition paradigm rather than a recall based experiment. While the 15 patients in this study represent a large sample size using a gestural communication system, carrying around a series of cards to prompt responses may not be feasible beyond the lab setting. While Danlioff s study successfully used gestures, many patients and their family members primarily focus on reestablishing spoken communication. In some cases this might be incredibly difficult to achieve and others might be able to make only a minimum amount of progress. While ultimately gesture based communication might be the most effective way to regain any type of effective communication skills, some people hesitate to pursue this course of action for fear that it will prevent any spoken language

19 One-Handed Simplified Signs 19 recovery. The literature suggests that this does not occur, and in fact, gestures or signed language actually support spoken communication. In Verbal and Simplified Sign System Treatments in Adults with Anomia of Speech, (Morgenstern, Braddock, Bonvillian, Steele, & Loncke) looked at a multimodal approach with three aphasic patients with Alzheimer s disease. The researchers used two treatments, a verbal communication approach and a simplified sign approach. The simplified sign system, originally developed by John Bonvillian and Nicole Kissane to help children with autism, consists primarily of signs taken from various sign languages throughout the world and new signs created specifically for this system. The signs strive to incorporate only the most simple handshapes and movements to achieve iconic, easy to form signs. There are over 1,000 signs in the simplified sign system, but it intentionally lacks the necessary components needed to qualify as a language. Instead, the system is designed to supplement users with poor verbal skills, and for the most severe cases, stand in as a mode of communication when the user cannot learn a full language. In this study, the patients each received both treatments in reverse order. The most important finding of this study is that the signs helped to fill in the gaps with speech and promoted the use of speech. In no way did the simplified signs seem to prevent speech. One limitation of this research, which occurs in many of these treatment programs, involves generalizing the lessons beyond the laboratory setting. Sitting with a researcher, a limited number of words or signs might be produced but eliciting the same responses elsewhere proves to be more difficult. Additionally, while some patients seem to benefit more from simplified signs, others do not and respond better to a speech-based intervention. Determining the best candidates for simplified sign use out of the larger pool of aphasic patients will

20 One-Handed Simplified Signs 20 eventually become an important area of study. While this is something to be addressed in future research, it is important to remember that even if the results are limited, it is better for these patients to have a few critical words or signs with which to communicate than none at all. Conclusions and Future Research The study of signed language and aphasia patients proves to be a rich field, providing new and interesting data benefiting everyone from neuroscientists to the patients themselves. Data from deficit studies provides biological information to support the linguistic conclusion that American Sign Language meets the criterion for a fullfledged language by suggesting that some brain structures support language function regardless of modality. Signed languages do take greater advantage of the right hemisphere than spoken language, which illuminates a potential pathway to communication for people with damage to the left hemisphere. A variety of treatment options exists for patients suffering from aphasia, many of which utilize some form of signed language to complement or supplement oral language. These treatments, while limited to a finite number of words, provide some relief for patients who, despite serious language impairments, have not lost their intellectual capabilities. The present study focuses on developing a sign-based approach that can be easily implemented outside of the laboratory. As previous researchers, such as Moody, have recognized, no current signed language adequately meets the needs of this population. American Sign Language and other genuine signed languages used by Deaf persons feature too many non-iconic signs and often use difficult to form handshapes and

21 One-Handed Simplified Signs 21 complex series of movements. Some studies have used AmerInd, as developed by Skelly, but this is a small and limited system of only 236 signs. The Simplified Sign System (Bonvillian, Kissane, Dooley, & Loncke, in press) used in the Morganstern study, provides the framework for attempting to develop a better fitting system. This system uses many iconic signs, single gestures, and basic handshapes, and focused on a core, functional, vocabulary. Modifications were made to many of the signs to use this system with aphasic patients. These modifications were made because of the hemiplegia that often co-occurs with patients language disabilities. Some of the original signs are one handed and remain the same in the present system. Others were two-handed symmetrical, meaning both hands use the same handshape and motion simultaneously; these signs will be retested to see if they can be performed with only one hand and retain their ease of recall. Still other signs in the Simplified Sign System do not fit into either of these categories, meaning that they use two hands doing two different things. For these signs, serious modifications were made in sign formation and completely new signs were devised. The present study tests the memorability and ease of formation of these signs, by asking non-impaired undergraduate students if they can recall the signs after being shown a list of signs. If the majority of the participants can perfectly recall the sign, then it will be saved for use with aphasic patients. If there are errors, the sign will be redesigned and tested again. The present study examines the results from testing of the first 240 words in the system. Ultimately, future research will be needed to finalize the remaining signs, test the signs with actual aphasic patients, and determine which members of this group would benefit the most from undergoing a sign treatment option. This pursuit of an effective

22 One-Handed Simplified Signs 22 one-handed sign system would require multiple steps, but could potentially help in the treatment of many aphasic patients. With a surprisingly large number of individuals with aphasia affected, both in the U.S. and overseas, it is critical that psychologists, linguists, and others continue to pursue the best avenue of communication therapy for this language disorder. Methods Participants The participants were 29 undergraduate students from the University of Virginia. The results from 28 of these participants were used in data analysis. Approximately twothirds of the participants were female. They participated in order to earn credit for research participation in their introductory psychology course. As part of the prescreening process, only students who stated that they were unfamiliar with a signed language were invited to participate in the study. None of the participants had an obvious disability that would have prevented them from seeing or reproducing any of the signs. Each person participated in an individual session that lasted approximately forty-five minutes. One student was not included because of an obvious sign production error on the part of the experimenter. Materials The first step in developing this one-handed version of the simplified sign system was determining which signs needed to be tested. Of the slightly over 1,000 entries in the original Simplified Sign System, almost 400 were already one-handed and were not tested again. The remaining signs needed to be redesigned and then retested to ensure

23 One-Handed Simplified Signs 23 they did not lose their ease of formation and memorability in their new form. Many of the remaining signs were two-handed symmetrical, meaning that both hands used the same handshape, motion, location and orientation and mirrored each other. Those signs were all retested using one hand, but the components of the sign stayed the same. The rest of the signs were two-handed asymmetrical, and required more effort to modify them into a one-handed version. Because of the constraints of this approach, some signs bear relatively little or no resemblance to their two-handed counterparts. Those signs that were created specifically for use in the one-handed system were designed with some general guidelines. First, signs had to have simple, predominantly unitary movements. Second, signs were intended to be iconic, in that the form and meaning of each sign was clearly related to its referent. Third, all signs were intended to be easily distinguishable from other signs in the system, though signs with conceptually similar meanings tend to take similar forms. Finally, the handshapes of the signs were primarily limited to those that are the easiest to form, including the A-hand, B-hand, 5- hand, C-hand, O-hand, baby O-hand, and G-hand (index finger). Two sets of 120 signs were composed from the large lexicon of potential one-handed simplified signs. Each set of 120 signs was divided into six lists of twenty words. The lists were designed to reflect a variety of sign forms and meanings. This helped to prevent signs from being presented close to others that were conceptually similar, causing increased difficulty for the participant to recall a sign accurately. Within each list, signs were placed in a random order with the constraint of trying to avoid having similar formations demonstrated one after the other. Six signs from the original system, unaltered because

24 One-Handed Simplified Signs 24 they were already one-handed, were used as a practice set for each participant to familiarize them with the procedure of the experiment. Procedure Data from 14 participants were examined for each set of signs. Each set of signs was presented to the participant in an individual session by an experimenter. The experimenter who presented the signs was not involved in rating the accuracy of each sign s production. The participants were asked to recall the signs in a completely different order than they had been shown. The participants were informed that the study involved recall of one-handed signs and heard specific instructions about the task they were being asked to complete. The study was conducted in an office-like setting. The experimenter and the participant sat in chairs facing each other, while a rater sat to the side of the experimenter. The participants were informed that they would be viewing several lists of signs and that they would be asked to recall the signs they had seen, when prompted with the signs English translation equivalents, at the end of each list. The experimenter asked the participants that while they were being shown the lists that they not move their hands in attempts to mimic the signs. The participants were told that each sign would be demonstrated to them twice, but that during recall they only needed to produce each sign once (Appendix A). The components of the scoring procedure were explained to each participant. They were told the four aspects of each sign that the rater would be examining; location, movement, handshape and orientation. At that time, one sample sign was shown, and the experimenter reviewed each of the four components with the participant, demonstrating what would constitute the correct formation of each aspect for that sign, and what would

25 One-Handed Simplified Signs 25 not. The rater looked at all of these components when determining the general score received for each sign, which could be either perfect, almost correct, wrong sign or no response (Appendix B). Signs that received a perfect rating were those that were identical to the sign presented by the experimenter. Almost Correct indicated that a sign produced by a participant was very similar to the presented one, but varied in one of the four components in a minimal way. The Wrong Sign category was reserved for signs that varied substantially from the one that had been demonstrated. This included signs that varied in two or more of the components, or in rare cases, signs that varied so much in one component that the sign was unrecognizable. A no response score meant that the participant failed to recall a given sign. Participants were instructed at the onset of the experiment that they could say No Response at any point during their attempt at sign recall, but were also encouraged to guess because there was no penalty for doing so. After showing each participant the sample sign, demonstrating signs from the practice list, and answering any of the participant s questions, the experimenter began by presenting the first list of twenty signs. Signs and their English counterparts were presented approximately every five seconds. The participants heard the English translation equivalent one time, and were shown the sign twice. After going through each list, each participant was immediately asked to recall the sign when cued with the English word. The participant had ten seconds to attempt the sign before the rater gave a No Response score. After completing all six lists, the participant was debriefed about the study and any questions about the nature or purpose of the study were answered (Appendix C).

26 One-Handed Simplified Signs 26 While the experimenter spent a considerable amount of time practicing the signs prior to the experiment, a video of all the signs was created to run simultaneously during the experiment. Only the experimenter could see this video; it was placed in a position that ensured the participant could not view the content. The video helped ensure that a high level of accuracy during presentation was maintained throughout the task, which required a lot of concentration and attention to detail. Additionally, the video helped maintain a consistent presentation time across participants. During recall, a separate rater scored each sign made by a participant. Over the course of the experiment, four different raters were used. An intense period of training occurred before each set prior to data collection to ensure an acceptable level of interrater agreement. Of the four raters, only one had significant experience with signed language, so this training period involved teaching the raters how to produce the signs. Each rater was given a written description of the signs. They had access to a video of the experimenter performing each sign that they used to study, in addition to meeting in person to practice each sign. In order to practice the scoring of sign formation, volunteers were solicited from friends and family members of the research team. These volunteers followed the same procedure as that of the actual experiment, including being provided with the informed consent agreement and the debriefing form. The raters practiced both individually and as a group. They practiced scoring the first set of word-sign pairs for nearly two months before formal data collection began to reach an acceptable level of inter-rater agreement in regards to the scoring of each of the different sign parameters. In general, an approximately 75% agreement between raters was established before data collection could begin. This number reflects the fine level of detail required to rate this

27 One-Handed Simplified Signs 27 task, which exceeds that which would be required in a real life setting. Additionally, the raters had a higher level of agreement for some components, such as location, than others, such as handshape. Again, this reflects the difficulty of the task, as participants were often not as accurate in discriminating between certain sign parameters as the experimenter. After each set of 120 signs was tested on 14 participants, the results were analyzed. If 10 or more participants signed a word perfectly, the sign was added to the Simplified Sign lexicon. If 8 or 9 participants performed the sign perfectly, then the sign was retested without any changes being made in its formation. If fewer than 8 participants recalled the sign perfectly, the sign was redesigned, based on the type of errors made by participants as recorded by the raters. Two sets consisting of a total of 240 word-sign pairs were tested in this study and each was placed into one of three categories: Met Criteria, Almost Met Criteria, and Failed to Meet Criteria (Appendix D). After changes are made to the signs that failed to meet the 70 percent or higher recall accuracy criterion, the signs, will be retested on 14 new participants in future word sets. The written description of each sign that met the criteria was added to a one-handed simplified sign system dictionary created by the experimenter (Appendix E). After creating the initial concepts for the signs that needed to be tested, modifications were made to signs that did not meet the goal of having 70% or more of participants recall them perfectly for re-testing with subsequent sets of participants.

28 One-Handed Simplified Signs 28 Results Sign Production and Recall Accuracy: Overall Findings For this study two sets, each containing 120 word-sign pairs for a total of 240, were tested for recall accuracy. For each set, the percentage of signs that met selection criteria, almost met selection criteria, and failed to meet criteria were calculated. To meet criteria, ten or more of the fourteen participants needed to perform the sign perfectly. To be included in the almost met criteria category, a sign had to have eight or nine participants form the sign correctly. The signs that fall into this category will be retested on fourteen new participants without being modified. If a sign had fewer than 8 people form it correctly, or not form the sign at all, resulting in a rating of no response, the sign was included in the failed to meet criteria category; this sign will be redesigned for testing in subsequent sets. Below are the scores for both sets and information pertaining to the overall percentage of signs that met criteria. (Table 1). Table 1: Percentage of Sign Recall Classifications (The raw score is first and the percentage follows.) Set Met Criteria Almost Met Criteria Failed to Meet Criteria 1 50 (41.67%) 8 (6.67%) 62 (51.67%) 2 38 (31.67%) 25 (20.84%) 57 (47.5%) All Sets 88 (36.67%) 33 (13.75%) 119 (49.58%) Total Scores for those that remain (Met +Almost Met) vs. Failed to meet 121 (50.42%) Included in data with Met Criteria 119 (49.58%)

29 One-Handed Simplified Signs 29 Out of the 240 words, 50 words met the criteria for inclusion in the one-handed lexicon from Set 1 and 38 words passed from Set 2. While the number of words that passed from Set 2 is lower than those from Set 1, 25 words from Set 2 were almost perfect compared with only 8 words from Set 1. Overall, 58 words from Set 1 and 63 words from Set 2, for a total of 121 words, will remain in the study at the present time. These numbers are a combination of those word-sign pairs that passed the selection criteria and those word-sign pairs that were close to meeting the selection criteria. These latter word-sign pairs will remain in the lexicon as originally designed unless otherwise precluded by future testing. This means that just over 50% of the word-sign pairs that were tested in this experiment will remain in the one-handed sign lexicon while the other half will require extensive editing and retesting. Sixty-two word-sign pairs from Set 1 and 57 words from Set 2 fall into the failed to meet criteria category and are currently being redesigned for future testing. Criteria for Addition to Lexicon In order for a sign to be added to the one-handed simplified sign system lexicon it must be recalled perfectly by at least 70% of the participants. For each set of words, data from fourteen participants were included. Since 70% of 14 is 9.8, 10 or more participants needed to perform the sign perfectly for it to be included. Of the 240 word-sign pairs, 88 were recalled perfectly by 70% or more of the participants. It is felt that these signs were highly iconic and quite easy to perform. That is, they had an easily made handshape and a single movement. An additional category of almost met criteria also was included. These 33 word-sign pairs received 8 or 9 perfect recall scores; this number was just below the score of 10 needed for immediate inclusion in the lexicon. Since these signs