This study sought to address the question:  How well do people recall simplified signs that are unfamiliar to them?  Although this question in itself is quite simple, its effectiveness is contingent on several delicately interwoven factors related to the parameters of a simplified sign system.  A simplified lexicon was intended to contain only strongly iconic and transparent, motorically accessible, and formationally simplified signs.  The ability of participants to immediately recall simplified signs with minimal errors was used to evaluate these criteria as well as our overall success in simplifying the signs. 
 

The present sign system was developed based on what was learned in the memory and recall of simplified signs by undergraduate participants.  The lexicon is composed of signs perfectly recalled by at least 70% of the participants and currently contains approximately 500 signs.  Among the limitations in conducting the present study with undergraduate students is the much higher cognitive and motor abilities of these students in comparison with those of disabled populations.  Although many of the simplified signs presented to the undergraduates were recalled perfectly, this would probably not have been the case if the experiment had been conducted on autistic, mentally retarded, and aphasic populations.  Using undergraduate participants to test the simplified signs poses the problem of their high intellectual ability and full motor functions which strongly contrasted to those of the special populations.  The level of recall by the undergraduates was used as a filter to identify strongly iconic signs.  According to previous research, the special populations have the greatest success in acquiring signs when the signs are strongly iconic. 
 

A second limitation in the present study is the relatively stark laboratory setting as opposed to the real environment in which the signs are intended.  It may be that in the noise and confusion of the real world that the learning and recall of signs may be much more complicated or difficult than in the laboratory setting.  A third limitation is that some of the present participants appeared to lose their concentration.  The participants may have become less interested in remembering each sign after having seen and recalled nearly 120 unfamiliar signs one after another in groups of 20.  The level of concentration, attitudes and effort put forth by the participants may have affected the lexicon since signs were most often recalled perfectly at the highest rates when the participants were intently focused during each and every sign presentation.  Since each sign was only performed for a four-second interval, a participant could easily miss a sign if not paying close attention.
 

The simplified system was developed according to four principles:  limitations, iconicity, semantic grouping, and formational ease.  According to the adopted definition of these parameters, all four principles are essential for a fully functioning simplified manual communication system.  It was attempted to meet these requirements in both the modified signs gathered form the formal sign dictionaries and in the signs deliberately invented for particular words. 
 

The proposed simplified sign system, composed of signs gathered from various formal sign language dictionaries and invented signs for specific needs, is as a whole very consistent.  Since the simplified system consists of modified signs intended to simplify their handshape, location, and movement formational aspects, the signs are all based on the same parameters of a simplified system.  By using the principles of limitations, semantic grouping, iconicity, and formational ease, it was possible to modify and design all of the signs according to a standardized criteria.  Although the signs were gathered from an array of dictionaries, they are not a hybrid, disjointed collection of manual signs.  The system benefits from the array of formal sign sources since each contributes a linguistic quality to the system in addition to following the four principles.   Similarly, since the system is limited in sophistication, complexity, and size, it remains a system and not a language.  If the system were to be considered a language, a more extensive lexicon would be necessary in addition to formal grammatical and morphological rules.
 

The principle of limitations was intended to constrain the level of linguistic complexity and limit the overall size of the system.  Previous researchers found that children with autism had unique cognitive and motor abilities that were directly related to their individual success in acquiring signs (Bonvillian & Blackburn, 1987; Seal & Bonvillian, 1997).  The simplified sign system is intended to overcome some of the limitations in acquisition by low functioning autistic, mentally retarded, and aphasic individuals.  By limiting the overall formational complexity of each sign, the motor skills and memory requirements involved in signing were reduced. In placing a limit on the overall number of signs incorporated into the lexicon, it was attempted to limit the complexity of the system as well.  For example, to minimize the confusion involved in labeling various people, people-oriented signs were limited to BOY, GIRL, MAN, WOMAN, DOCTOR, NURSE, MOTHER, FATHER, and FRIEND.  Specific titles and names for all of the caretakers and individual people present in daily life (e.g., the mailman, the secretary at the doctor’s office, the cafeteria staff) were not incorporated into the lexicon.  Similarly, food groups were broadly categorized as SANDWICH, SOUP, SWEET, SNACK and the overall MEAL.  Specific meals like hamburger, soda, or pizza were not added in order to limit the size and complexity of signs and their meanings. 
 

The principle of semantic grouping demanded that the lexicon of approximately 500 words convey an array of meanings in a general and nonspecific sense.  By the principle of semantic grouping, generalized signs become more specific when placed in context with appropriate situations.  For example, the generalized sign for WOMAN may refer to an aunt or godmother at a family gathering, a babysitter at home, or an attendant at an institution or care facility.  Although the same sign is used in all of these situations, the associations between the woman and her context clarifies the generalizations made by semantic grouping of meanings.
 

In examining the contents of the simplified lexicon, more signs are needed to further describe additional generalized semantic connotations.  Similarly, there are numerous signs that repeat the same semantic association.  For example the signs for FLY and AIRPORT, which are both currently in the lexicon, indicate either planes, flying, or airports.  However, two separate signs are not truly necessary for the level of communication needed by persons with disabilities.  Perhaps a more useful overall sign would be for TRAVEL which would semantically associate such lexicon signs as TRAIN, CAR, BOAT, and AIRPLANE in terms of generalized transportation sources. 
 

The principle of iconicity was strongly challenged in the study of immediate memory and recall.  In order to perfectly recall an unfamiliar sign with no practice and only a four-second presentation interval, the sign must make a great deal of sense to the participant, in terms of its direct and obvious tie to its referent.  In developing the lexicon, iconicity was made a major priority for each sign in several ways.  Iconicity was understood to be based on the imitation of the referent’s stereotypical characteristics, tracing or directly pointing to physical objects or parts of the body, evoking states and characteristic emotions, and mimicking actions associated with signs.  In order for a sign to be considered strongly iconic, it was intended to incorporate many of these characteristics into each formation.  As a result of the high level of perfect scores across the sets of signs, these simplified signs are indeed strongly iconic.  Since the participants were unfamiliar with the simplified signs and sign language in general, the mean recall of perfect signs of over 80% indicated that many signs successfully had clearly transparent or iconic meanings.
 

In creating clearly transparent and iconic associations between the sign and its referent, it was also hoped that strong iconicity would facilitate learning and acquisition of signs by fully functioning individuals.  Since both the participants in this study and the caregivers and family of the special populations are all cognitively and motorically fully functioning individuals, high levels of recall by the participants may be indicative of the level of recall that might be achieved by caregivers.  If this is the case, iconicity facilitated learning and acquisition of signs in terms of immediate and highly accurate recall of unfamiliar signs. 
 

This conclusion is similar to those by studies examining the nonspeaking, but hearing, populations and the effect of strongly iconic signs.  Although sign iconicity and transparency may be helpful to caregivers’ “sign” learning, the factor appears to be quite important in the sign learning of nonspeaking but hearing populations.  Iconic signs were shown to be more easily comprehended and recalled by mental retarded children (Griffith & Robinson, 1980) autistic children (Konstantareas, Oxman, & Webster, 1978), and aphasic individuals (Coelho & Duffy, 1986).  According to the previous research, verb iconic signs were shown to be easily acquired by the hearing, but nonspeaking, populations (Coelho & Duffy, 1986; Konstantareas et al., 1978). 
 

The composition of verb and noun iconic signs in the simplified lexicon may affect acquisition of signs by autistic, mentally retarded, and aphasic individuals.  Noun signs comprise approximately 50% of the present simplified sign lexicon.  This compared to verbs which comprise approximately 40% of the lexicon.  Adjective, adverbs, and prepositions are the remaining 10% of the lexicon.  This may indicate that noun signs were more strongly iconic and easily recalled than verb signs.  In the development of future simplified signs, this should be taken into consideration and efforts should be made to make both verbs and nouns as strongly iconic as possible. 
 

The dimension of iconicity that was so intently focused upon while selecting a lexicon of the signs may actually end up being a factor lost on some young children and some severely disabled persons since they lack the cognitive abilities needed to see the relationship between the sign and its referent.  This is because some cases of autism, mental retardation, and aphasia may be too severe for simplified sign acquisition and those persons may need to seek a more basic means of augmentative communication.  The simplified signs were intended to encompass the needs and wants most relevant to the special populations.  As a result, iconic ties were made to the most basic referents.  For example, in creating a sign for BATHROOM or TOILET, the iconic reference is to one’s full bladder and urgent, anxious feeling of need to use the bathroom very badly.  This incorporated natural gestures and even emotion into the signs making it iconic on a very basic level, touching upon several aspects of the associated meanings. 
 

The tie between the meaning of signs and their referents may have had a significant impact on the high levels of recall of some signs.  In particular, when common natural gestures and mimicking techniques were used to illustrate sign meanings, often extremely high levels of perfect scores were obtained.  Thus, it was felt that the origin or etymology of the sign may have been directly related to its successful recall.  The etymology or sign origin was included to facilitate learning and remembrance by both the special populations and the caregivers.  In order for the special populations to benefit from a signs tie to its referent, the ties must be cognitively easy to understand and as a result, associated with some daily life activity or piece of very common knowledge.  It was hoped that this direct tie to the referent would  further facilitate caregiver knowledge of the simplified signs with minimal training.  Such signs as BOY, GIRL, PREGNANT, and TELEPHONE indicated a clear tie to their referent which therefore explains their high level of perfect recall by participants.
 

The principle of formational ease was contingent upon a minimal level of motoric complexity with regard to the number of movements in a particular sign, as well as its handshape, location, movement, and spatial orientation.  The motoric complexity of a sign limited the handshape to particular forms and positions according to previous research.  Certain specific sign locations (trunk, chin, forehead, neutral place, 5-hand, cheek, midface) which are known to be more easily acquired than others (upper arm, supinated wrist) were specifically selected for the motorically simplified signs (Wright, Bonvillian, & Schulman, 1998).  When modifying the handshapes of the signs, those based on prior research were preferentially selected as follows: G-hand, A-hand, B-hand, 5-hand.  Other handshapes that were occasionally selected, but not as often owing to historically less accurate production, included the C-hand and O-hand (Wright, Bonvillian, & Schulman, 1998).  Body contact, specific pointing, tracing, and tapping were all used to further emphasize sign locations and intended meaning.  The number of movements included in each sign was taken to its minimal level, with nearly every sign in the lexicon having only one specific movement; only a few had two movements.  The ease of position of a sign was facilitated since each sign tested was able to be done with only one arm and with a limited range of movement.  Thus, even signs like TALL, which required participants to reach up high and show someone tall in height, could be done at a lower level with less reaching and still convey the intended meaning with proper spatial orientation.  Similarly, if individuals in any of the special populations prefer to form their signs symmetrically by using both hands, most of the signs in the lexicon can be made using both hands at once.  More specifically, about 97% of the signs are able to be performed accurately with bilateral symmetry.  Nearly all of the signs in the lexicon also can be done unilaterally.
 

The presentation of some signs was intentionally accompanied by an emphatic facial expression when performed by the experimenter.  Sometimes formationally perfect signs were recalled by participants were of the emphatic emotional expression and associated sentiment (e.g., a huge grin for HAPPY, a sad frown for CRY, and a lowered brow for ANGRY).  Facial expression was not scored as part of the formational accuracy, but may have been helpful for the participants in recalling the sign.  Additional ties to a sign’s referent may have been displayed by accompanying signs with such strong and passionate emotional expressions.  Since many signs with incorporated facial expressions were performed with high rates of accuracy, such expressions or emotional content may have added another dimension by which to associate signs and place them in context.  These facial expressions may have also enabled signs to be related even more to common natural gestures based on emotion, especially those triggered by a state of being or sentiment. 
 

The simplified lexicon contains approximately 520 signs.  A lexicon of about 500 signs may be sufficient for a simplified system.  In previous studies, autistic, mentally retarded, and aphasic individuals rarely master more than 500 signs.  A lexicon greater than 500 signs would begin to resemble a formal sign language, and linguistic and grammatical rules would begin to apply.  Since many full and genuine manual languages already exist, if a nonspeaking person is capable of understanding and using more than 500 signs, they are likely to be above the cognitive and motoric levels for which the simplified signs were developed.  These individuals might well benefit from learning a formal sign language instead of a simplified system.  Since the present signs are intended to constitute a relatively simple means of communicating, the current total of about 500 signs should be sufficient for communicative expression.  Likewise, this simplified sign system is intended to be a true “system,” not a language.  As a system it can bypass the need for all of the complexities associated with languages, which previous research showed was a source of difficulty for special populations (Bonvillian & Nelson, 1978).
 

Further examination of the signs in the present lexicon may show that many signs may still be needed.  Such signs likely will be more important for everyday use than some of the present signs already in the lexicon.  In order to further develop the system, missing signs or concepts must be identified, generated, and added to the lexicon.  Unnecessary signs must be eliminated, or semantically grouped together with other signs of similar meaning.  This introduces the principle of semantic grouping, which was developed in order to generalize many associated ideas and words into all-encompassing simplified signs. 
 

Upon critical examination of the proposed lexicon, one may even wonder if a sign system is in fact easier to learn than a formal sign or spoken language.  In simplifying the signs it was hoped to place significantly fewer cognitive demands on the learner.  Formal signs languages and spoken languages all have genuine linguistic components and grammatical rules.  The present system was invented to make all of these rules and components dramatically easier by eliminating many of them, and closely relating the others to the intended meaning of the word or phrase.  During the process of generating these new signs, certain signs produced in isolation (as in the testing for this study) may have been only iconic to intellectually intact persons (the undergraduate participants). These signs may in fact have been added unnecessarily to the lexicon during the earlier stages of the experiment when our primary concern was to identify any iconic sign from the many formal dictionaries that were searched.
 

With further testing of additional signs, a general idea emerged and better grasp of the needed signs for special populations (for example those that were invented specifically for the classroom, emergencies, and medical situations).  We also became increasingly familiar with the formations and movements that participants recalled perfectly most often.  As a result, simplified signs that were invented in the latter sets of signs were likely to be more appropriate for the basic needs of the special populations, and to require formations and positions we had associated with high iconic accuracy.  Once signs begin to be used by the autistic, mentally retarded, and aphasic individuals, as well as their caregivers, the superfluous ones will be identified and then eliminated or combined with others as signs that are more needed are developed and incorporated into the system. 
 

In spite of the many advances autistic, mentally retarded, and aphasic individuals make with learning to communicate using manual signs, attitudes toward non-oral communication for hearing individuals may remain skeptical.  Even though reports indicate that by learning one functioning means of communication an individual has a greater likelihood for learning another, many still believe that once a child learns to sign, further progress towards speech is halted (Bonvillian & Nelson, 1978).  Similarly, many caregivers hesitate to teach sign communication to hearing but nonspeaking individuals because of the significant time commitment needed on their part to acquire the system. 
 

These negative views toward sign intervention programs for hearing, but nonspeaking, individuals, were taken into consideration when developing a simplified sign system.  Since each sign is strongly iconic and modified for formational ease in handshape, position, and movement, the time spent training in the system in order to comprehend and use signs correctly should be minimal.  By definition, strongly iconic signs should be readily apparent in meaning and facilitate learning by autistic, mentally retarded, and aphasic individuals, and their caregivers.  The simplified system was also designed to serve as a continuum between oral and non-oral language.   When speaking persons use the system to communicate with nonspeaking persons, they are supposed to vocally say the English equivalent of the word while they simultaneous perform the simplified sign.   This reinforces both the understanding of verbal communication by nonspeaking individuals, and the association of meaning shared between the spoken word and manual sign.  Since hearing, but nonspeaking, individuals using the simplified sign system are not completely devoid of spoken language interaction, caregivers may not hesitate to use this simplified communications program since it provides them with the use of both verbal and manual language. 
 

 Several of the present findings suggest possibilities for future research.  For example, this study has shown that undergraduates can recall simplified signs accurately after a single presentation.  It would be worthwhile to investigate how performance changes over the course of time, with repeated presentations, or after corrective feedback.  Since the participants in this study are not accustomed to learning and immediately recalling manual signs, they may be limited in their ability to accurately reproduce signs with proper handshapes, locations, and movements owing to their limited skill and experience in observing and performing such formations. 
 

 The next step in the development of the simplified system is to introduce the signs to the special populations and caregivers for which it was intended.  In order to reach a wide audience of autistic, mentally retarded, and aphasic individuals, as well as their principal caregivers, teachers, physicians, family members, hospital and institution staff, and friends, the simplified lexicon has been posted on the World Wide Web at a registered domain name of simplifiedsigns.org.  People interested in the simplified system will be able to examine, criticize, use, and provide suggestions and feedback, through simplifiedsigns.org.  Additionally, related information and links concerning the implementation of sign intervention programs, slide presentations of the use and intention of the simplified sign system, and this thesis document are all available on the web site for the special populations and their caregivers to use and to read more about the system.  In order to correctly form the signs and understand their iconic and transparent referents, each sign on the web will ultimately be posted alongside a formational definition and its specific iconic reference.  For example, the sign for BOOK would be visually depicted alongside its formational definition of  “Handshape:  B-hands;  Movement:  two palms together ‘open’”  and its iconic referent of “opening and closing a book.”  Since the simplified sign system was initially created based on signs appearing to have a high level of iconicity during immediate cued recall by undergraduate college students, the effectiveness of the system in the cognitively and motorically disabled populations for which it was designed is essential in revising and adding to the current lexicon.  It will be interesting to explore the efficacy of this simplified system in assisting autistic, mentally retarded, and aphasic individuals to communicate, and to continue in the development of the lexicon and simplified system to  better serve the needs of these populations.