Motor learning principles and voice pedagogy: theory and practice.
It is often the case that the practice of a skill, whether motor or perceptual, is equated with the learning of it. However, true learning as defined in the cognitive and motor learning domains requires both long-term retention and generalization of the skill. Long-term retention is the ability to perform at or near the same accuracy level attained during the acquisition (training) stage; generalization is the ability of that individual to transfer or carry over what has been trained into new but similar tasks.
One example of this would be if a tennis player learned to better coordinate all muscles involved for a forward swing through extended training on that movement, and the backhand swing also improved substantially even though no direct training had occurred during that time period. An example from the voice studio would be if a student were working on vocal warm-up exercises that focused on bringing more balance or roundness of timbre (chiaroscuro) to the chest register, but as a result the middle and head registers were noticeably rounder and more balanced in timbre as well.
A few definitions of basic concepts used in the perceptual-motor learning domain will prove useful for the discussions to follow. Motor learning refers to "a set of processes associated with practice or experience leading to relatively permanent changes in the capability for movement" or "an area of study focusing on the acquisition of skilled movements as a result of practice." (1) Similar to motor learning, perceptual learning refers to observed improvement found in different sensory tasks as a result of practice, training, or simple exposure. Motor control is "an area of study dealing with the understanding of the neural, physical, and behavioral aspects of movement." A motor program is defined as an organized set of motor commands that are typically specified before movement initiation. (2)
TYPE OF PRACTICE: BLOCKED VERSUS RANDOM PRESENTATION OF STIMULI
A primary means of attaining skilled vocal performance is substantial amounts of practice. Two commonly used practice formats in motor learning are blocked and random practice sessions. In both formats, several tasks are trained. In blocked practice format, tasks are trained sequentially within a session; each specific task is trained completely before practice on remaining tasks begins. In random practice format, tasks are trained in parallel, with practice trials of each task interspersed with practice on the other tasks (in no predetermined or patterned order). For both practice formats, the same total number of trials per task is completed. In the voice studio, the teacher could choose to have the student work on one piece for 15 minutes, another piece for 15 minutes, a third piece for 15 minutes, and a fourth piece for 15 minutes (a blocked order), or he/she could choose to cut the time spent on each piece to no more than seven minutes at a time, and alternate among the four pieces more frequently throughout the lesson period without repeating the same sequence each time (a random order).
The effect of blocked versus random practice format on learning has been extensively studied. An early and important investigation into the benefits of random versus blocked practice was completed by Shea and Morgan, who found that blocked practice resulted in more rapid acquisition of the movement patterns (so the subjects performed better during the training stage). However, in retention tests, those receiving random practice significantly outperformed those who had received blocked practice. (3)
Other studies also have found that random practice results in increased accuracy in learning and retention. A simultaneous learning effect was studied in the context of subjects being asked to remember lists of words. They found that when a list of words is learned simultaneously with other lists, the rate of forgetting is lower than those who learned a single word list alone. This is, in effect, a validation of the advantage of random practice over blocked. For the vocal performer, it may therefore be best to memorize more than one piece at a time. (4)
Han, et al. completed a study on the effects on learning under blocked versus random practice schedules using an auditory model applied to the learning of timing sequences. They found that a "blocked followed by random practice" condition (blocked-random) resulted in overall learning that was superior to the other practice schedules (e.g., random-blocked, blocked-blocked, random-random). The auditory model created an additional positive effect on learning regardless of the practice schedule. (5)
The effect of spacing of practice sessions combined with random versus blocked practice was studied by Rohrer with application to mathematics problems. Results revealed that spacing provides a review that improves long-term retention, and mixing (randomizing different types of problems) improves student's ability to pair a problem with the appropriate concept or procedure. The conclusion was that although a random practice protocol is more demanding than blocked practice, because students cannot assume that every problem is based on the immediately preceding problem (or is similar to it), the apparent benefits of such a protocol are evidenced in retention and generalization tests. (6) This idea could be applied in a voice lesson, by randomizing the order of specific targeted exercises or type of literature from lesson to lesson and within each lesson. It could also be applied to an individual song in a lesson, by breaking it up into several sections and randomly practicing them (skipping around).
CONTEXTUAL INTERFERENCE EFFECT
One possible explanation of why a random practice format results in better learning (relative to blocked practice) is called the contextual interference effect which proposes that: 1) factors that make a task more difficult for the individual enhance remembering and transfer; 2) intertask facilitation is produced by intratask interference, which is caused by an attempt to keep multiple items in immediate memory at one time; 3) the net effect of high interference is increased learning and retention. This interference may present itself in one of two forms: the order in which multiple items were practiced (random versus blocked), and the nature of the material to be practiced. If the same task is practiced repeatedly, then only one task needs to be held in the working memory, and interference should be low. However, if practice involves many changes between multiple tasks, then interference should be high. (7) This could again be the case when a voice teacher asks a student to randomly rotate among four or more songs throughout a lesson, or when different sections within a song are practiced randomly in a lesson.
Ollis, et al. studied the influence of professional expertise (or previous experience with a similar or related task) and task complexity (simple versus complex) on the effect of contextual interference. They asked forty-eight firefighters (novice or experienced) to practice tying either simple or complex knots, presented in either blocked or random order. The contextual interference effect was strongest for the novice "knot-tiers" even when the task was complex. It is plausible to propose that we could compare undergraduate voice majors to graduate voice majors here, with the undergraduate students representing the "novices" and the graduate students representing the "experienced." In this case, undergraduate voice students may benefit from this type of approach (use of contextual interference) even more than graduate voice students would. (8)
The benefits of random practice on long-term retention are supported by numerous studies. Results indicated a distinct overall performance advantage for a random practice schedule compared to a blocked schedule for both acquisition and retention, and random practice also facilitates transfer of learning to untrained or novel tasks. Results also indicated that for both transfer accuracy and consistency, random (variable) practice is more effective than practice at a constant criterion, and when transfer will be outside of the practice boundaries, random variable practice is superior. (9) Following this principle, it may be wise to have voice students practice or "train" in a variety of environments and venues, rather than isolate the lesson to the voice studio. If a student were able to feel confident and comfortable in maintaining the solid technique acquired in lessons in a variety of settings with distinct acoustic properties, different sizes of audiences, and at different times of day, then the likelihood of a real performance being carried out with less chance for "error" may well increase. In practical settings, it appears that attempts to make the practice more variable for learners (singers) will result in greater learning and generalization.
FORGETTING AND RECONSTRUCTING HYPOTHESIS
Closely related to the contextual interference principle is the forgetting and reconstructing hypothesis, which emphasizes the role of the construction of previously forgotten action plans (e.g., muscle "memory" for a specific vocalise) as a basis for learning. If tasks are presented in a random format, there is more opportunity to "forget" what action was taken the last time that task was presented, thereby requiring a reconstruction of the motor planning strategies necessary to complete the task. This is believed to solidify the creation of the neural pathways (which occurs when learning a new or novel task) by a complete use and reuse of these newly created paths. Rather than only having to partially "re-trace" the neural steps just taken, the individual is forced to start all over at the beginning of the "path"
Induced forgetting of an acquisition task was studied by Shea, et al. The forgetting was created by performance of either a similar or dissimilar distracter task during the intertrial interval. Results indicated that the retention of the acquisition task was better if the interfering task was similar, rather than different, from the task being acquired. The authors concluded that "forgetting and subsequent reconstruction alone are not sufficient for improved retention. These processes must occur in the context of a similar task for improved retention" (10) One possible way to implement this would be to record or videotape the voice lesson, then require the student to review it before the next lesson (preferably on the same day as the next lesson, but before the lesson time) and complete a written reflection on aspects the student thought he did well and things that need to be improved.
"PARTS" VERSUS "WHOLE" PRACTICE
Another area of relevance in motor learning is the concept of "parts" versus "whole" practice of a complex task. This issue revolves around whether a complex task (e.g., vocal performance) that will ultimately be performed in its entirety (as a "whole") benefits most from a "parts" practice approach or a "whole" practice approach. The "parts" approach consists of a practice routine that breaks down the components of the complex task into separate items, followed by the expectation that the final task will be the simultaneous execution of those subtasks. The "whole" approach to learning a complex task refers to tasks that are practiced only and always as a "whole" event (without breaking it down into its composite parts).
Lim, et al. looked at the effects of part-task and whole-task instructional approaches on acquisition and transfer of a complex cognitive skill. The study also compared two levels of learners' prior knowledge of the task (lower versus higher). The learners exposed to the "whole-task" instructional approach performed significantly better than the "part-task" group of learners in both a skill acquisition task and a transfer or generalization test. (11) A study comparing three approaches to learning a complex polyrhythmic perceptual motor task using partpractice, whole-practice, and part/whole practice, found that the whole practice approach produced better acquisition, retention, and transfer of learning, even if part of the task was practiced separately first (part-practice) followed immediately by a whole-practice approach. (12)
A similar result was found in an investigation of part-whole practice of movement sequences. A 16-element movement sequence was taught under part-whole practice (parts practice followed by whole practice) versus whole-practice only conditions. Although retention tests showed little difference between the two groups, transfer tests revealed that the group who received part-whole practice performed more quickly than the whole-practice group. The suggestion was that the whole-practice group appeared to code the sequence so that it was relatively difficult to fully partition it into separate movements; therefore on the transfer tests, there continued to be residual effects of a "slowed down rate" found from the whole-practice condition. (13)
The implications for the voice studio are relatively clear in this case. Since we as performers must ultimately "perform" the act of singing as a holistic task comprised of many various components woven effortlessly and consistently together, the question is whether it is best to train this "whole" task with a "parts" or a "whole" practice approach. This is a decision worth careful consideration. Like some of the other motor learning concepts examined here, a distinction may be warranted between novice or beginning singing students and more advanced ones.
DISTRIBUTION OF PRACTICE: MASSED VERSUS SPACED PRACTICE SCHEDULES
The frequency with which voice lessons or choir rehearsals are scheduled is often an issue under debate among voice pedagogues. Practice distribution, or practice over time, is a predominant area of research in motor learning concerned with determining the best way to distribute the time spent in work (or "training") versus the time spent resting. Several studies have indicated that practice distribution has large effects both on temporary performance levels during acquisition and relatively permanent influences on learning. (14) "Practice" in this context can be thought of as the "training" or the acquisition stage of learning a new skill.
Two primary practice distribution schedules have been researched: massed and spaced. In a massed practice schedule, all the practice periods occur very closely together with little or no rest time in between periods of practice. In a spaced practice schedule, the time interval between the practice periods is increased significantly, allowing periods of "x" number of hours, days, weeks, or months to go by before another practice period is scheduled.
Three studies investigating the massed versus spaced practice schedules were completed in the context of aphasia therapy. Aphasia is an expressive, receptive, or mixed language impairment commonly found in patients after a stroke has occurred. Investigators have compared the effect of massed or intensive therapy (also called "constraint induced aphasia therapy" or CIAT) with traditional spaced therapy protocols. Results indicated that although both types of therapy resulted in significantly improved language function, the increase was more pronounced for the patients who received the intense therapy regime (averaging 8.8 hours/week over 11.2 weeks). The traditional therapy schedule (averaging 2.0 hours/ week over 22.9 weeks) practiced by the control groups "failed to achieve comparable improvements." (15)
In addition to massed and spaced practice schedules, a third possible option worth considering is a "self-regulated" practice scheduling method. Keetch, et al.
found that when participants were placed in groups that ordered the practice items into blocked, random, or self-regulated patterns of presentation, the self-regulated group showed the most improvement in performance in retention tasks, even though they did not show any advantage during the acquisition stage. This advantage in the retention task held true regardless of task complexity. (16)
In the voice studio, it is worth questioning the wisdom of the traditional method of voice lesson scheduling, which would be considered "spaced" in the context of motor learning. One might consider teaching a student three times per week for 20 minutes each time rather than one session per week for 60 minutes, in order to approach a more "massed" practice schedule. Although the practicality and complexity of scheduling in the real world may well preclude this, nevertheless it poses an interesting theoretical question.
The other extreme of massed versus spaced practice scheduling is found in day long choir rehearsals in preparation for a performance the same evening, similar to what is commonly required for an all-state choir participant. The assumed benefit of that type of marathon rehearsal needs to be sincerely questioned when one considers the cost in both mental and physical fatigue, and the resulting negative impact on the final performance.
CLOSED VERSUS OPEN TASKS/ CONSTANT VERSUS VARIABLE PRACTICE
Both perceptual and motor tasks can differ in the inherent amount of variability typically expected within a specific task. "Open" tasks are defined as those that contain a great deal of variability (such as fielding ground balls or returning a tennis serve), and it is crucial to successful performance of such tasks that the learner acquire the capability to cope with novel situations. Since the task itself will ultimately involve variability, it is plausible to believe that the most effective practice situations should include some measure of variability as well. "Closed" tasks occur with a great deal of constancy (such as archery or cooking), and for these tasks, the most effective practice situations should incorporate decreased variability (or increased constancy).
In the training of professional voices, it is a general consensus that there are very specific and consistent models or ideals for timbre, range, and flexibility of the voice, which in the context of motor learning would qualify them as "closed" tasks. The characteristics of an acceptable performance are fairly consistent when compared both by Fach and also by regional taste. But what is not strictly controlled, what can never be fully described nor taught in any prescribed manner, is what the performer uniquely brings to the performance in terms of artistic decisions based upon the text, music, and the variance from one performance to another (e.g., a repeat performance of an operatic role from one night to the next may not be an exact carbon copy of the previous night, or being in opera "x" in one company may yield a different resulting performance than being in opera "x" with another company). It is this artistry and these types of parameters that would qualify as "open" tasks.
Some evidence suggests that variable practice may be just as important for closed tasks as it is for open tasks. (17) Variable practice appears to increase the ability to apply the learning that occurred during acquisition to the performance of a novel task and to the performance of novel variations of the task that are well outside the range of the stimuli experienced in the acquisition stage (e.g., private lesson performance versus live peer-reviewed performance in a concert hall).
AUGMENTED FEEDBACK: KNOWLEDGE OF RESULTS/ KNOWLEDGE OF PERFORMANCE
A critical part of learning new motor skills, like vocal performance, is receiving feedback about performance or accuracy. Feedback that is added to what is typically received in the task (sensory or intrinsic feedback) is called augmented feedback. Since its source is outside of the body, augmented feedback is also known as extrinsic feedback. Augmented feedback can have a negative effect on motor skill learning if it is provided too frequently, in a form that is too easy to use, or is presented in a manner upon which the individual can become dependent.
Augmented feedback may be presented in the form of verbal, visual, or auditory information provided to the subject during the acquisition stage of perceptual or motor learning task and may be presented as knowledge of results (KR) or knowledge of performance (KP). While knowledge of performance (KP) provides information
about actual components of the performance itself, knowledge of results (KR) is typically auditory, verbal, or visual post movement information about the performance outcome. Knowledge of results may be specified by type, timing, precision, and relative frequency. It may be immediate or delayed by a specified period of time following a response. It may be presented after every response (100% feedback) or in summary form, after "x" number of responses (e.g., 25% feedback would be provided after every fourth response). KR may be precise or allow a margin of error called a "bandwidth," and it may be quantitative or qualitative in nature.
Precision of knowledge of results refers to the amount of accuracy with which the KR is given. Performance tends to improve with increased precision of KR up to a point, after which increased precision will not result in increased learning. Relevant choices in precision of KR include providing quantitative feedback (e.g., "you were one beat late for that entrance," "you were a half step flat on that high C"); qualitative feedback (e.g., "good" "that was better," "absolutely beautiful!"); or a combination of both types of feedback combined with the use of a goal-related bandwidth of correctness.
Research involving the effects of qualitative versus quantitative KR has shown more improvement in accuracy for quantitative and qualitative KR groups than for groups receiving either a nonsense KR or a no-KR (for both acquisition and retention). Quantitative KR groups perform better than the qualitative KR groups. (18) Qualitative feedback, when provided alone or when combined with quantitative feedback, results in superior skill acquisition, but decreased retention of that skill. (19) Increased response accuracy has been shown to be directly related to increased precision of KR, and this relationship is maintained throughout all the retention blocks as well. (20)
Some research has suggested that feedback after "good" trials or execution of a task enhances learning. It is a generally agreed upon fact that learners prefer to receive feedback after they believe they have had a "good" rather than a "bad" trial. In another experiment, feedback was provided either after "good" or "bad" trials. While there were no group differences during practice, the group receiving the feedback only after "good" trials demonstrated learning advantages in a delayed retention test (without any KR). The results suggested that learning is enhanced or facilitated if feedback is provided after "good" rather than "poor" trials. (21) This harks back to the traditional "positive" versus "negative" reinforcement concepts from psychology.
Studies on the effects of relative frequency of KR have demonstrated that performance accuracy was enhanced when KR was present; however, performance consistency was enhanced with decreased or absent KR. One study looked at the effects of modeled auditory information on a sequential timing task using frequency of the provision of the auditory model as the influencing factor (100% or 50%). Groups who received an auditory model showed enhanced learning. The 50% group did not appear to become dependent on the auditory model, however, significant decrements in performance were observed for the 100% group when the auditory model was withdrawn. (22)
The influence of frequency of feedback (KR) on coordination strategies was studied by Ranganathan, et al. Groups were comprised of 100% KR frequency, 50% KR frequency, and concurrent feedback. These strategies were incorporated into learning a discrete force-production task. Although the concurrent feedback group demonstrated fewer errors during acquisition, they had the highest errors in a no-KR transfer test. This group appeared to adopt a strategy that tended to use multiple solutions to achieve the goal during acquisition, but they were unable to retain this strategy in the no-KR test. (23)
Memmert, et al. studied the conditions of practice in perceptual skill learning looking at not only a blocked versus random comparison, but also an "easy to hard" ordering of task complexity. Results indicated that a training program that gradually increases the difficulty level has no advantage over a training program that randomizes the ordering of task complexity. Also observed was the advantage that the random group had over the blocked group in the retention test and that training with reduced feedback (provided 66% of the time) is not more effective than with 100% feedback training provided one is training a group of novice performers. (24) It is plausible that this difference in the benefit of increased versus decreased frequency of feedback may apply to the training of vocal novices versus more advanced voice students. It is also not uncommon to find a novice or insecure voice student constantly seeking feedback or approval from the voice teacher (100% continuous feedback), which significantly distracts them from the completion of the task, and results in either not completing it at all or doing so with greatly reduced accuracy and precision.
The role of previous experience and the nature of augmented feedback on subsequent learning and retention of a bimanual coordination pattern were investigated. Results indicated that new learning "overshadowed the influence of the intrinsic patterns" (the previous skill and/or knowledge in the same area). The authors also concluded that "learning was also greatly affected by augmented feedback: dynamic, on-line pursuit tracking information was more effective for transfer than static, terminal feedback." (25) This online feedback in effect provided an errorless learning paradigm.
A delayed-KR study was completed which revealed that a delayed-KR approach produced learners who performed significantly less accurately during the acquisition phase of the study but showed a significantly smaller performance decline from acquisition to retention phases. The suggestion based on these results was that the delayed-KR group used a greater variety of intrinsic feedback sources and its members were more likely to report that their usage changed with practice. (26)
Research in the area of augmented feedback is vast, and includes studies on the informational role of KR in motor learning, when to provide KR to the subjects, bandwidth knowledge of results versus relative frequency effects, and error-KR versus no error-KR, among others. Results of these studies have suggested that KR serves to assist the subject in making necessary adjustments between trials, better learning tends to occur under the random presentation of KR schedules than the blocked KR schedules, and random presentation of KR facilitates both skill acquisition and retention. (27)
Knowledge of performance (KP) may be more appropriate in early treatment phases while knowledge of results (KR) is more appropriate as the individual gains more control and "self-monitoring" in their motor processing system. In the voice studio, one might consider incorporating more use of KP for beginning voice students and more use of KR for more advanced voice students.
Guidance is a technique frequently used in teaching, athletics, and rehabilitation. It is also a technique frequently used in the voice studio. The learner is guided in some way through the specific tasks to be learned. These guidance procedures tend to prevent the learner from making errors in the task. In the guidance hypothesis, it is predicted that the guiding properties of augmented feedback are beneficial for learning when used to reduce error, but detrimental when relied upon. Therefore, heavy use of a guided form of feedback might be detrimental for learning. (28) Additionally, physical guidance conditions sometimes result in the poorest retention, while auditory feedback during acquisition produces less error during both the acquisition and retention phases. (29)
Yiu, et al. completed research using biofeedback in the form of electroymyography (EMG) when used in the context of a voice production task (learning a relaxed laryngeal musculature task during spoken reading). This EMG feedback was either provided during the task (concurrent) or following a successful execution of the task (terminal). Decreased muscle activation levels from baseline measures through training and retention no-feedback testing phases were observed. Additionally, not only did the target muscles improve in performance (more relaxed), but this benefit generalized to another untargeted muscle group (orofacial sites).30 In another study, real-time visual feedback of voice acoustics was incorporated in the training of singing skills. The visual display allowed the singer to see how well their voice approached the desired "target" and to immediately observe the effect of altering their manner of singing. This visual feedback was facilitative in the development of motor skills and helped students in the modification of their auditory perceptual models of appropriate singing voice qualities. (31)
However, "real-time" or on-line visualized acoustic biofeedback must be used with caution in certain circumstances. Syrja, et al. completed a study on the effect of two-month vocal exercising with and without spectral biofeedback on student actors' speaking voices. The authors used real-time spectrum analysis with the target of a "ringing" voice quality with strong overtones in the 3-5 kHz range. Fundamental frequency, sound pressure level (SPL), and long-term average spectrum (LTAS) analyses were completed. Although the sound energy at 3-5 kHz did increase, it was not correlated with increased SPL. Fundamental frequency slightly increased in the biofeedback group and slightly decreased in the control group. Relative decibel level of the fundamental frequency decreased, however, in the biofeedback group which the authors believed suggested tighter adduction. They concluded that although visual feedback may add some efficacy in voice training, there may be an accompanying risk of hyperfunctional voice production, especially if other sensory feedback is neglected (e.g., proprioceptive feedback). (32)
This is an area worth examination in voice instruction. How are we "guiding" our students? Are we providing physical cues as feedback? Are we providing verbal guidance (e.g., auditory feedback)? Which of the two types of guidance is best in terms of true vocal learning? The research would suggest that while both may be beneficial to a point, auditory feedback may be the superior choice, and too much of either type of guidance could prove detrimental to our students' ultimate learning experience. This may fly in the face of what so many voice pedagogues have been doing for a long time, providing both an auditory and physical model for their students to emulate (for example, proper breathing techniques, or physical "cues" about the "correctness" of a particular placement of the tone or timbre). Perhaps the wisest course of action would be not to "throw the baby out with the bath water," however, until more specific research can be completed in the context of actual voice studios.
ERRORLESS VERSUS ERRORFUL LEARNING
Errorless learning attempts to provide an acquisition phase that discourages any errors whatsoever from being made, in order to strengthen the perceptual trace that ultimately leads to retention; (33) whereas errorful learning provides an acquisition (training) phase in which individuals are allowed to make errors, because it is through the execution of these errors that the individual defines and refines the production and retention of the target behavior. (34) In the voice studio, we must determine how many and what types of "errors" we will allow/tolerate before responding with a comment or corrective suggestion.
Wills, et al. looked at prediction errors and attention in the presence and absence of feedback. It is often assumed that we learn more when our predictions (about our accuracy) turn out to be incorrect than when they turn out to be correct. One explanation for this is that we
seem to direct visual (or auditory) attention toward the likely causes of the previous "prediction errors." This can happen rapidly (< 200 ms) after the error-causing object is presented. The authors conclude that substantial learning can sometimes be the result of simple exposure to objects, and that this may be the result of directing attention toward the likely causes of previous prediction errors. (35)
In another study, intermodal transfer from a visual to an auditory discrimination task was investigated using an errorless learning procedure. Two training procedures were employed, trial-and-error and errorless. Results indicated that errorless learning was effective in transferring from a visual to an auditory discrimination task. This would imply that if the goal is ultimately the transfer of learning from one modality to another (for example, from an auditory goal to a physical goal or vice-versa in the voice studio), then perhaps "errorless" learning would be best. Once again, it may be that this errorless learning is best suited to novice singers while "errorful" learning facilitates the best results with more experienced and advanced singers. (36)
The concepts of frequency of KR, the guidance hypothesis, and errorful versus errorless learning are somewhat related. One hundred percent KR creates a very strong guidance effect and prevents or discourages the learner from making mistakes (errorless learning), while 25% KR allows for more errorful learning and decreases the guidance effect.
Many investigators in the perceptual and motor learning domain have researched the relationships between implicit and explicit memory and the type of task being learned. Studies in errorless versus errorful learning have shown that tasks or situations that facilitate retrieval of implicit memory for the learned material (such as learning names with a first letter cue) will benefit from errorless learning methods, while those that require the explicit recall of novel associations (such as learning routes around a room or judging vocal qualities) will not benefit from errorless learning, and in fact appear to benefit to some extent from the trial and error learning mode. (37)
The challenge, then, is to determine whether the majority of techniques and skills acquired in a voice training regime require the use of implicit or explicit memory, or some combination of both. It may be that in the confines of a voice lesson with supervision resulting in another person acting as "judge," the training is more "errorless" (calling upon implicit memory); while in the practice room when the student has to rely solely on his own judgments, the training is more "errorful" (calling upon explicit memory). Alternatively, it may be that inexperienced or beginning voice teachers tend to strive for a more "errorless" lesson environment than more experienced teachers, who feel the confidence to allow the student to engage in a bit more "self-discovery." Perhaps the best type of learning or recall is task-specific; for example, the execution of an accurate rendition of the musical score itself needs by virtue to be "errorless" (using implicit memory), while the execution of a recently acquired specific vocal technique may benefit most from "errorful" learning (using explicit memory) and will most likely be more "errorful" in production.
PREDICTING INDIVIDUAL DIFFERENCES IN SKILL ACQUISITION
A good deal of interest has been demonstrated over the last fifteen years in the individual differences in abilities, skills, and genetic predisposition versus extensive exposure or practice of a specific task. An ability is a "hypothetical construct that underlies or supports performance in a number of tasks or activities" and is usually a relatively stable characteristic or trait for that individual. This differs from a skill, in that abilities are "the underlying capabilities that support certain skills." The ability itself is relatively stable, while the skills can be modified, improved, or even decline with decreased use. A given skill may be comprised of a number of different abilities. (38) To some extent, an ability can be thought of as similar to a person's IQ, while skills are the amount or type of information learned as a result of an individual's underlying IQ. In the voice studio, this appears as differences noted between singers that are attributed to having "more" or "less" natural underlying talent or ability.
Research has shown that individual differences in performance can be caused by being either an expert or a novice for a given task or set of tasks. The principle of specificity is a theory about the structure of motor abilities which states that motor tasks are thought to be composed of many independent abilities. (39) This principle may extend to the differences seen between experts and novices. When differences occur, they often are specific to the task or knowledge represented by the nature of the expert's "expertise." However, some research has failed to show any differences between experts and non-experts in general measures of motor ability, such as response time, visual abilities, and general knowledge. Some studies have revealed significant differences between these groups while others have not reached statistical significance. A few of these studies have compared musicians to nonmusicians (40) and the differences between experienced and novice listeners. (41) These differences in individual results are hypothesized to be due to the efficacy of training methods, specific acoustic properties requisite in a given voice quality, or the interference of extraneous variables.
Ericsson, et al. presented a theoretical framework that explained expert performance as an end result of many years of practice and efforts to improve performance, and that most expert performers began their childhood with a regimen of effortful activities (deliberate practice) designed to optimize improvement. Individual differences among expert performers are closely related to amounts of deliberate practice. The authors conclude that many characteristics once believed to reflect innate talents are actually the result of intense practice extended for a minimum of 10 years. (42)
While this large amount of practice over time is without a doubt a contributor to ultimate success and the attainment of the professional singer status, individual differences also may play a role in determining which individuals will reach the highest levels of skilled performance in tasks involving speech and accuracy of motor movements (e.g., singing). Ackerman, et al. presented an overview of new developments in understanding skilled performance. They stated that content abilities (like math, verbal, and spatial abilities) can be important predictors of individual differences in performances of novice learners (or beginning singers). Two other ability types, perceptual speed and psychomotor ability, are thought to be as good, if not better, predictors of performance after extensive practice (or advanced singers). The authors stated that "although practice is the primary determinant of individual differences in skilled performance of tasks with significant motor requirements, the sheer amount of practice provides only a moderate amount of explanatory power. The kind of practice (e.g., motivated, purposeful) appears to be an important factor, especially for sports and musical skills." This sounds reminiscent of the old "it's not the quantity but the quality that counts" adage used to describe important activities, accomplishments, and achievements, or time spent on any important feature of one's life. (43)
THEORY VERSUS PRACTICEFINAL CONSIDERATIONS
It is perhaps understandable that the experienced voice pedagogue is somewhat reticent to plunge into this "strange and new world" of motor learning principles with any attempt to apply them to the voice studio. This may be particularly true for those gifted teachers whose students have traveled far and wide and enjoyed successful and rewarding professional singing careers. The true artist, however, is never afraid of looking at things in a different light, exploring new options, and even changing one's perspective. The artist's willingness to remain open-minded and to truly live out one's days as a "life-long learner" may indeed result in volitional changes in habitual patterns of behavior or vocal pedagogic practices. In this regard, they are not so unlike the scientists who have researched and developed these principles. It is reassuring to find that many of the motor learning principles reviewed in this article have traditionally been a part of the training of the singing voice; now one must remain open to continuing to grow as a professional, even if change and growth is at times "painful." A tremendous amount of energy and effort has gone into trying to understand the underlying principles that guide our ability to learn. Perhaps it is incumbent upon us as teaching professionals to seek ways of applying this information to the work that we do in training our young artists.
The very first rehearsal of the new cycle had left no doubts that the Winterreise was in stark contrast to the general run of sentimentally complacent Lieder of the age. Schubert was therefore understandably reluctant to part with the songs before they had attained their definitive form; certainly none of his other songs underwent so much revision and re-touching as did those of the Winterreise.
Dietrich Fischer-Dieskau, Schubert's Songs: A Biographical Study, p. 259.
(1.) R. A. Schmidt and T. D. Lee, Motor Control and Learning: A Behavioral Emphasis, 4th ed. (Champaign, IL: Human Kinetics, 2005).
(2.) S. W. Keele, "Movement Control in Skilled Motor Performance," Psychological Bulletin 70 (1968): 387-403.
(3.) J. B. Shea and R. L. Morgan, "Contextual Interference Effects on the Acquisition, Retention, and Transfer of a Motor Skill," Journal of Experimental Psychology: Human Learning and Memory no. 5 (August 1979): 179-87.
(4.) D. J. Burns and M. V. Ladd, "The Simultaneous Learning Effect: Why Does Simultaneous Task Learning Improve Retention?" American Journal of Psychology 119, no. 3 (September 2006): 385-405.
(5.) D. W. Han and C. H. Shea, "Auditory Model: Effects on Learning Under Blocked and Random Practice Schedules" Research Quarterly for Exercise and Sport 79, no. 4 (January 2008): 476-486.
(6.) D. Rohrer, "The Effects of Spacing and Mixing Practice Problems," Journal for Research in Mathematics Education 40, no. 1 (August 2009): 4-17.
(7.) W. F. Battig, "Intratask Interference as a Source of Facilitation in Transfer and Retention," in R. F. Thompson and J. F. Voss, eds., Topics in Learning and Performance (New York: Academic Press, 1972).
(8.) S. Ollis, C. Button, and M. Fairweather, "The Influence of Professional Expertise and Task Complexity Upon the Potency of the Contextual Interference Effect" Acta Psychologica 118, no. 3 (September 2005): 229-44.
(9.) T. D. Lee, R. A. Magill, and D. Weeks, "Influence of Practice Schedule on Testing Schema Theory Predictions in Adults" Journal of Motor Behavior 17 (1985): 283-99; T. D. Lee and H. Carnahan, "When to Provide Knowledge of Results During Motor Learning: Scheduling Effects" Human Performance 3 (June 1990): 87-105; D. A. Simon and R. A. Bjork, "Metacognition in Motor Learning," Journal of Experimental Psychology: Learning, Memory, and Cognition 27, no. 4 (July 2001): 907-12; D. A. Simon, T. D. Lee, and J. Cullen, "Win-Shift, Lose-Stay: Contingent Switching and Contextual Interference in Motor Learning," Perceptual and Motor Skills 107, no. 2 (October 2008): 407-218.
(10.) J. B. Shea and D. L. Wright, "When Forgetting Benefits Motor Retention," Research Quarterly of Exercise Sports 62, no. 3 (September 1991): 293-301.
(11.) J. Lim, R. Reiser, and Z. Olina, "The Effects of Part-Task and Whole-Task Instructional Approaches on Acquisition and Transfer of a Complex Cognitive Skill," Educational Technology Research & Development 57, no. 1 (February 2009): 61-77.
(12.) S. Kurtz and T. D. Lee, "Part and Whole Perceptual-Motor Practice of a Polyrhythm," Neuroscience Letters 338, no. 3 (March 2003): 205-209.
(13.) J. H. Park, H. Wilde, and C. H. Shea, "Part-Whole Practice of Movement Sequences," Journal of Motor Behavior 36, no. 1 (March 2004): 51-61.
(14.) T. D. Lee and E. D. Genovese, "Distribution of Practice in Motor Skill Acquisition: Learning and Performance Effects Reconsidered," Research Quarterly for Exercise and Sport 59 (1988): 277-87; J. A. Adams and B. Reynolds, "Effect of Shift in Distribution of Practice Conditions Following Interpolated Rest," Journal of Experimental Psychology 47 (1954): 32-26.
(15.) M. Meinzer, D. Djundja, G. Barthel, T. Elbert, and B. Rockstroh, "Long-term Stability of Improved Language Functions in Chronic Aphasia After Constraint-Induced Aphasia Therapy," Stroke 36, no. 7 (July 2005): 1462-6; F. Pulvermuller, B. Neininger, T. Elbert, B. Mohr, B. Rockstroh, P. Koebbel, and E. Taub, "Constraint-Induced Therapy of Chronic Aphasia After Stroke," Stroke 32, no. 1 (January 2001): 1621-6; S. K. Bhogal, R.Teasell, and M. Speechley, "Intensity of Aphasia Therapy, Impact on Recovery" Stroke 34, no. 4 (April 2003): 987-93.
(16.) K. M. Keetch and T. D. Lee, "The Effect of Self-Regulated and Experimenter-Imposed Practice Schedules on Motor Learning for Tasks of Varying Difficulty," Research Quarterly for Exercise and Sport 78, no. 5 (December 2007): 476-486.
(17.) Lee, Magill, and Weeks; D. C. Shapiro and R. A. Schmidt, "The Schema Theory: Recent Evidence and Developmental Implications," in J. A. Kelso and J. Clark, eds., The Development of Movement Control and Coordination (New York: Wiley, 1982), 113-150; J. H. A. Van Rossum, "Schmidt's Schema Theory: The Empirical Base of the Variability. Error-Free Learning in the Rehabilitation of People with Memory Impairments," Journal of Head Trauma Rehabilitation 11, no. 2 (April 1996): 54-64.
(18.) M. H. Trowbridge and H. Cason, "An Experimental Study of Thorndike's Theory of Learning," Journal of General Psychology 7 (1932): 245-260.
(19.) N. C. Kilduski and M. S. Rice, "Qualitative and Quantitative Knowledge of Results: Effects on Motor Learning," American Journal of Occupational Therapy 57, no. 3 (May/June 2003): 329-36.
(20.) D. M. Bennett and R. W. Simmons, "Effects of Precision of Knowledge of Results on Acquisition and Retention of a Simple Motor Skill" Perceptual and Motor Skills 58 (June 1984): 784-86.
(21.) S. Chiviacowsky and G. Wulf, "Feedback After Good Trials Enhances Learning," Research Quarterly for Exercise and Sport 78, no. 2 (March 2007): 40-47.
(22.) Q. L. Lai, C. H. Shea, and M. Little, "Effects of Modeled Auditory Information on a Sequential Timing Task," Research Quarterly for Exercise and Sport 71, no. 4 (December 2000): 349-356.
(23.) R. Ranganathan and K. M. Newell, "Influence of Augmented Feedback on Coordination Strategies," Journal of Motor Behavior 41, no. 4 (July 2009): 317-330.
(24.) D. Memmert, N. Hagemann, R. Althoetmar, S. Geppert, and D. Seller, "Conditions of Practice in Perceptual Skill Learning," Research Quarterly for Exercise and Sport 80, no. 1 (March 2009): 32-43.
(25.) S. R. Hurley and T. D. Lee, "The Influence of Augmented Feedback and Prior Learning on the Acquisition of a New Bimanual Coordination Pattern" Human Movement Science 25, no. 3 (June 2006): 339-48.
(26.) D. I. Anderson, R. A. Magill, H. Sekiya, and G. Ryan, "Support for an Explanation of the Guidance Effect in Motor Skill Learning," Journal of Motor Behavior 37, no. 3 (May 2005): 231-238.
(27.) J. R. Blackwell and K. M. Newell, "The Informational Role of Knowledge of Results in Motor Learning," Acta Psychologica 92, no. 2 (July 1996): 119-129; Lee and Carnahan, "When to Provide Knowledge"; T. D. Lee and H. Carnahan, "Bandwidth Knowledge of Results and Motor Learning: More Than Just a Relative Frequency Effect" The Quarterly Journal of Experimental Psychology 42:A (November 1990b): 777-89.
(28.) R. A. Schmidt, D. E. Young, S. Swinnen, and D. C. Shapiro, "Summary Knowledge of Results for Skill Acquisition: Support for the Guidance Hypothesis," Journal of Experimental Psychology: Learning, Memory, and Cognition 15, no. 2 (March 1989): 352-9.
(29.) C. J. Winstein, P. S. Pohl, and R. Lewthwaite, "Effects of Physical Guidance and Knowledge of Results on Motor Learning-Support for the Guidance Hypothesis," Research Quarterly for Exercise and Sport 65, no. 4 (March 1994): 316323; R. M. Kohl and C. H. Shea, "Augmenting Motor Responses with Auditory Information-Guidance Hypothesis Implications," Human Performance 8, no. 4 (February 1995): 327-43.
(30.) E. M. Yiu, K. Verdolini, and L. P. Chow, "Electromyographic Study of Motor Learning for a Voice Production Task," Journal of Speech, Language, and Hearing Research 48, no. 6 (December 2005): 1254-1268.
(31.) W. Thorpe, P. Wilson, J. Crane, J. Van Doom, and J. Callaghan, "Real-Time Visual Feedback of Voice Acoustics for the Training of Singing Skills" Australian Journal of Psychology 55 (August 2003): 94-96.
(32.) T. Syrja, A. M. Laukkanen, M. Laitala, and T. Leino, "Effects of Two-Month Vocal Exercising With and Without Spectral Biofeedback on Student Actors' Speaking Voice," Logopedics Phoniatrics Vocology 29, no. 2 (June 2004): 66-76.
(33.) J. A. Adams, "A Closed-Loop Theory of Motor Learning," Journal of Motor Behavior 3 (1971): 111-50.
(34.) R. A. Schmidt, "A Schema Theory of Discrete Motor Skill Learning," Psychological Review 82 (July 1975): 225-60.
(35.) A. J. Wills, "Prediction Errors and Attention in the Presence and Absence of Feedback," Current Directions in Psychological Science 18, no. 2 (April 2009): 95-100.
(36.) J. Arantes and M. Berg. "Intermodal Transfer from a Visual to an Auditory Discrimination Using an Errorless Learning Procedure," Behavioral Processes 81, no. 2 (June 2009): 303-308.
(37.) J. J. Evans, B. A. Wilson, U. Schuri, J. Andrade, A. Baddeley, O. Bruna, T. Canavan, S. Della Sala, R. Green, R. Laaksonen, L. Lorenzi, and I. Taussik, "A Comparison of 'Errorless' and 'Trial-and-Error' Learning Methods for Teaching Individuals with Acquired Memory Deficits," Neuropsychological Rehabilitation 10, no. 1 (January 2000): 67-101.
(38.) R. A. Schmidt, D. Young, S. Swinnen, and D. Shapiro, "Summary Knowledge of Results for Skill Acquisition: Support for the Guidance Hypothesis," Journal of Experimental Psychology: Learning, Memory, and Cognition 15, no. 2 (March 1989): 352-9.
(39.) F. M. Henry, "Specificity Versus Generality in Learning Motor Skill," in R. C. Brown and G. S. Kenyon, eds., Classical Studies on Physical Activity (Engelwood Cliffs, NJ: Prentice-Hall, 1968; original work published in 1958).
(40.) C. C. Bergan and I. R. Titze, "Perception of Pitch and Roughness in Vocal Signals with Subharmonics," Journal of Voice 15, no. 2 (June 2001): 165-75; C. C. Bergan, I. R. Titze, and B. Story, "Perception of Two Vocal Qualities in a Synthesized Vocal Utterance: Ring and Pressed Voice," Journal of Voice 18, no. 3 (September 2004): 305-317; I. R. Titze, C. C. Bergan, E. J. Hunter, and B. Story, "Source and Filter Adjustments Affecting the Perception of the Vocal Qualities Twang and Yawn," Logopedics, Phoniatrics, and Vocology 28, no. 4 (October 2003): 147-155.
(41.) Y. Wang, M. M. Spence, A. Jongman, and J. A. Sereno, "Training American Listeners to Perceive Mandarin Tones," Journal of the Acoustical Society of America 106, no. 6 (1999): 3649-58; Y. Wang, A. Jongman, and J. A. Sereno, "Acoustic and Perceptual Evaluation of Mandarin Tone Productions Before and After Perceptual Training," Journal of the Acoustical Society of America 113, no. 2 (February 2003): 1033-43.
(42.) K. A. Ericsson, R. T. Krampert, and C. Teschromer, "The Role of Deliberate Practice in the Acquisition of Expert Performance," Psychological Review 100, no. 3 (July 1993): 363-406.
(43.) P. L. Ackerman, "New Developments in Understanding Skilled Performance," Association for Psychological Science 16, no. 5 (2007): 235-239.
Christine Bergan, MM, PhD, CCC-SLP is the program director of the speech-language pathology and audiology program at Stephen F. Austin State University in Nacogdoches, Texas, where she also serves as assistant professor. She teaches both graduate and undergraduate level courses and supervises graduate student clinicians who assess and treat a wide range of patients with diverse etiologies. She has a master's degree in vocal performance from University of Northern Iowa and a master's degree in speech-language pathology from the University of Iowa. She completed a PhD in Voice Science (Speech and Hearing Science) from the University of Iowa under the direction of Ingo Titze. Her dissertation topic was the application of perceptual-motor learning principles to auditory training in the perception of voice qualities.
Dr. Bergan has been the primary author of two published articles and second author of a third published article: "Perception of Pitch and Roughness in Vocal Signals with Subharmonics," Journal of Voice (2001); "Perception of Two Vocal Qualities in a Synthesized Vocal Utterance: Ring and Pressed Voice," Journal of Voice (2003); and "Source and Filter Adjustments Affecting the Perception of the Vocal Qualities Twang and Yawn," Logopedics, Phoniatrics, and Vocology (2003). In addition, she has appeared as guest presenter at three of the annual Symposium: Care of the Professional Voice conventions in Philadelphia, PA, sponsored by the Voice Foundation, most recently this past June, 2009.
Dr. Bergan is a member of The Voice Foundation, National Association of Teachers of Singing, and the American Speech and Hearing Association, through which she is a licensed speech-language pathologist. She has appeared as guest lecturer or presenter at workshops in Oklahoma and Texas focusing on the integration of voice science into vocal artistry and the possibilities that exist in careers that combine the two domains.
Dr. Bergan has continued to be an active performer both as a soloist and as a member of the St. Louis Symphony Chorus from June, 2008-June, 2009. She has performed as a soloist in Carnegie Hall, on NPR, and as the guest artist with symphony orchestras across the Midwest. She continues to teach private voice and piano lessons, and has over twenty years of experience as a private studio voice teacher. Her love of singing and teaching singing has been combined with an immense respect and appreciation for voice science, and her passion continues to be the successful marriage of art and science.
|Printer friendly Cite/link Email Feedback|
|Title Annotation:||MINDFUL VOICE|
|Publication:||Journal of Singing|
|Date:||Mar 1, 2010|
|Previous Article:||Music theory for voice students.|
|Next Article:||Louis Graveure, 1888-1965.|