Over the centuries, teachers of singing have used a predominately psychological approach to voice training (Fields, 1947; Burgin, 1973; Monahan, 1978). This approach emphasizes mental imagery and attitude as the primary elements in vocal training. In recent years, however, a great amount has been learned about the physical aspects of vocal sound production. Consequently, a trend toward a more physiological approach to voice training has recently appeared (Rose, 1962; Vennard, 1967; Burgin, 1973; Lee, 1977; Lamb, 1979; Reid, 1984; Sundberg, 1987). This trend has influenced private voice teachers and vocal music educators at all levels.

While the emphasis on a primarily psychological approach to the teaching of singing still thrives among private voice teachers (Miller, 1985; Cleveland, 1989a), many are also recognizing the importance of scientific knowledge. Numerous articles in recent vocal pedagogy journals emphasize the importance of vocal science knowledge to the contemporary voice teacher (Reid, 1984; Cleveland, 1988; Miller, 1989; Spencer, 1989; Cleveland, 1990; Titze, 1991). Knowledge of the anatomy and function of the vocal instrument is being emphasized for vocal and choral music educators as well. In the research-based text Teaching Kids To Sing (1992), Phillips emphasizes that teachers of singing need to have a basic understanding of the physical structure of the voice so that they can diagnose problems and correct faulty singing techniques. In addition, research indicates that students as young as age 10 benefit from instruction in basic vocal anatomy (Merrion, 1989). Further, in a 1990 survey (Crabb & Pembrook), 1000 college choral directors rated knowledge of the vocal mechanism as the most important proficiency for their profession. Research such as this indicates that a working knowledge of voice science is necessary for vocal music educators at all levels.

The growing emphasis upon the significance of vocal science knowledge has, of course, resulted in an effort to include more coursework on voice science in the curricula for undergraduate music majors. Despite this trend, however, there appears to be relatively little focus upon the development of new and effective instructional approaches for conveying this rapidly accelerating range of knowledge. Vocal science information has been presented almost exclusively via the lecture approach despite the fact that "the majority of students tested are not auditory learners, results which certainly do not support the widespread use of the 'lecture' method" (Dunn, Dunn, & Price, 1979, p. 53). While a number of fine texts, videos, and other visual aids are available as supplements to the lecture (Cleveland, 1989b; Cleveland, 1989c), lecture presentation still appears to be the primary mode of instruction.

The use of computer-assisted instruction (CAI) in the area of vocal pedagogy could potentially provide an instructional alternative that is effective, efficient, and relatively inexpensive given the availability of computers. According to Price (1989), research between 1970 and 1985 "consistently found CAI to be effective in terms of improving student achievement, saving student time, and fostering positive attitudes on the part of both teachers and students" (p. 154). Further, as a result of the more efficient use of learning time, more class time could be spent on higher level skills and application of voice science information. The abilities of CAI to present anatomical information paired with animated illustrations, simulate the articulation and function of the laryngeal process in singing, and also provide individualized assessment linked with appropriate review seem particularly appropriate for the presentation of voice science information.

Hyper Vocal Anatomy (HVA) is a Hypercard-based CAI focusing on the anatomy and function of the larynx. The design process for HVA took into consideration those aspects recommended by Sankar in a 1988 article on the evaluation of computer-assisted instruction: target audience, specific learning objectives, students' modes of learning, and methods of evaluation.

HVA was designed and programmed with a focus on the training of undergraduate students. While the primary purpose for the development of HVA centered on instruction in vocal pedagogy, musical knowledge is not a prerequisite and, therefore, other potential uses for HVA were considered (for example, training in voice pathology).

The development of specific learning objectives is the most important step in the design of any instructional strategy. The learning objectives for HVA focus on: (a) the names, locations, and characteristics of the primary cartilages and muscles in the larynx; (b) the function and interaction of these cartilages and muscles; and (c) the fundamental phonation process. The information presented in the CAI was drawn from a variety of significant sources on vocal anatomy and physiology. These sources include texts by Appleman (1967), Vennard (1967), Zemlin (1981), Perkins & Kent (1986), and Sundberg (1987). The resulting material was organized into two fundamental sections or "stacks" in Hypercard terminology: one stack focusing on laryngeal cartilages and the other presenting the basic laryngeal muscles.

In an attempt to address learning style issues, both cognitive processing and perception were considered when planning the presentational method. At the beginning of each of the cartilage and muscle stacks, the learner is offered the option of proceeding through the material sequentially or randomly. The sequential option presents the information in an order predetermined by the programmer. The random mode allows the user to determine the order of presentation by clicking on any specific anatomical feature of the larynx. The random option can also serve as a technique for focused and efficient review. The unique capabilities of Hypercard were utilized to address perceptual considerations as well. Both of the anatomy stacks provide illustrations of the cartilages or muscles as well as information about their position and function in the larynx. Learners can check their knowledge by using the mouse to click on specific anatomical features. Feedback and/or further information is then provided via hidden fields or animation. In some cases, learners need to click on specific features before being allowed to continue. In addition, the user can contract and release the various laryngeal muscles, resulting in visual simulations of the function of each muscle. Use of all of the above programming techniques provides a link between three of the primary perceptual modes: the abstract by the presentation of written material, the visual via illustrations and animation, and the tactile by requiring the physical movement of the mouse-controlled pointer to identify requested anatomical features. The remaining perceptual learning mode, aural, is addressed via the vocal simulator stacks. By providing aural feedback which reflects changing vocal pitch and intensity, the simulators help HVA users make a connection between muscle/cartilage function and the resulting effect on vocal sound. The simulator stacks also provide an opportunity for free exploration, discovery learning, and the development of a higher level of understanding of the vocal process by requiring the use of problem solving skills.

Finally, HVA is capable of providing users with accurate information regarding their level of knowledge and then directing review as needed. The Click Anatomy stack was developed to provide drill and practice, assessment, and directed review based upon the specific information with which the user is having difficulty. HVA also includes programming that records and stores the learning path and responses of the user. This information is available to the instructor via a data dumping routine.

A field-test of HVA and two rather extensive studies have provided quantitative and qualitative data that have been used to refine and establish the effectiveness of the CAI (Ester, 1992). The most recent and thorough study compared the effectiveness of HVA, lecture, and a combined lecture-HVA approach to teaching vocal anatomy and function to undergraduate music students with different learning styles.

The subjects in this study were 52 undergraduate music students attending two large midwestern universities. All subjects completed a pretest and the Gregorc Style Delineator prior to treatment. The pretest instrument was the 35-question Vocal Anatomy Test (VAT) designed by the researcher. The VAT consists of 18 identification questions which require the student to write in the proper name of the illustrated cartilage or muscle, and 17 multiple choice questions focusing on laryngeal function. Data indicate that this measure is both highly reliable (.90) and valid (Ester, 1992). The Gregorc Style Delineator (Gregorc, 1985) is a self-report instrument that involves the rank-ordering of four words in each of ten sets. It can be completed in less than 5 minutes. The Style Delineator categorizes learners into four learning styles: concrete random, abstract random, concrete sequential, and abstract sequential. Gregorc reports internal consistency reliability of

.89 - .93, test-retest reliability of .85 - .88, and predictive validity of .55 - .76. Following the pretest procedure, subjects were randomly assigned to one of the three treatment groups.

The lecture students received a study sheet and attended a total of 100 minutes of lecture. The CAI students received a study sheet and attended a 15-minute orientation on using HVA. Each student also received an HVA computer disk. All remaining instruction for the CAI group resulted from the independent use of HVA. The students in the combined treatment group received a study sheet, attended the entire lecture, attended the HVA orientation session, and received an HVA disk. Following treatment, all students were posttested via the VAT. In addition, subjects completed the Post-Treatment General Information Form: a 2-page form requesting information regarding time spent studying and/or working with HVA and general impressions of the instructional approach.

The effects of the independent variables, teaching method and learning style, on the dependent variable, knowledge of vocal anatomy and function, were analyzed using a two-way ANCOVA with GPA and Pretest serving as covariates. All of the fundamental assumptions upon which ANCOVA is based, including homogeneity of regression, were met. Descriptive statistics associated with the posttest are reported in Table 1. A summary of the two-way ANCOVA results for main effects and the interaction appears in Table 2.

TREATMENT

L Lecture CAI Combined

E

A n 6 n 13 n 7 n 26

R Concrete M 19.99 M 21.18 M 24.95 M 22.04

N SD 3.29 SD 2.19 SD 2.97 SD 1.66

I

N n 10 n 9 n 7 n 26

G Abstract M 16.00 M 28.42 M 21.91 M 22.11

SD 2.49 SD 2.66 SD 2.99 SD 1.58

S n 16 n 22 n 14

T M 17.99 M 24.80 M 23.43

Y SD 2.06 SD 1.71 SD 2.11

L N 52

E *Maximumscore 35 GrandM 21.90

Covariates

Pretest 3.59 1 3.59 0.06 .813

GPA 1024.57 1 1024.57 16.20 .000 *

Main Effects

Treatment 417.10 2 208.55 3.30 .046 *

Learning Style 0.05 1 0.05 0.001 .977

Interaction

Treatment x LS 359.84 2 179.92 2.845 .069

Residual 2782.95 44 63.249

F tests associated with GPA, a covariate, and treatment, one of the independent variables, are significant. Statistically, then, after accounting for variance resulting from student GPA, the treatment had a significant effect on the achievement of subjects as measured by the posttest (p = .046). Post-hoc tests were performed using the Bonferonni adjustment. The results of these tests are reported in Table 3.

Lecture 1.000

CAI 0.045 * 1.000

Combined 0.219 1.000 1.000

Probability values revealed that subjects in the CAI group demonstrated significantly higher achievement than those in the lecture group, while subjects in the CAI and combined groups performed equally well.

Analysis of data collected via the Post-treatment General Information Form indicated that subjects in the three treatment groups engaged in the same amount of independent study time (studying lecture notes and/or working with HVA). The chi-square test for independence was nonsignificant, X2 (6, n = 52) = 1.58, p >.05.

The results of this study support the conclusion that HVA is an effective and efficient method for teaching basic vocal anatomy and function to undergraduate students. As such, it provides an independent, self-paced instructional alternative to the traditional classroom lecture approach. The use of HVA as one component of vocal pedagogy classes can free instructors from spending precious class time on the presentation of basic laryngeal anatomy and function information and allow them to focus on the application of this knowledge. HVA also provides an effective alternative to the frequent re-teaching that is necessary when presenting new and somewhat complex terms. The effectiveness of HVA should encourage the design and development of CAI materials focusing on the anatomy and function of the respiration/support and vocal resonance aspects of singing. The selective use of CAI to teach specific topics such as these can provide valuable assistance to vocal pedagogy instructors intent on presenting current vocal science knowledge to their students.