By Matthew Nishimoto

Experts possess a large (potentially unlimited) number of domain-specific schemas. Hierarchically organized schemas represent experts’ knowledge in the domain and allow experts to categorize multiple elements of related information as a single, higher level element. When confronted with a specific configuration of elements, experts are able to recognize the pattern as a familiar schema and treat (and act on) the whole configuration as a single unit. When brought into working memory, a single, high-level element requires considerably less working memory capacity for processing than the many low-level elements it incorporates, thus reducing the burden on working memory. As a consequence, acquired schemas, held in long term memory, allow experts to avoid processing overwhelming amounts of information and effectively reduce the burden on limited capacity working memory. In addition . . . experts are able to bypass working memory capacity limitations by having many of their schemas highly automated due to extensive practice.[1]

Guitarists in the position of teaching guitar to students—studio teachers, college professors, classroom teachers—are expected to hold a level of expertise. Through instruction, guitar pedagogues are further expected to transform that expert knowledge into representations of information that novice guitarists cannot only understand but apply. Representations of this expert content knowledge as consumed by novices can manifest in many forms: explanations, modeling, written/drawn representations, etc. This article is intended to shed light on a particular negative phenomenon related to this process of content expertise and its transfer, via instruction, to novices. This phenomenon is known as the expert blind spot effect, the tendency for content experts to represent their advanced knowledge by their own internal expert schema rather than the representation that may be appropriate for a novice learner.[2]

I. The Underlying Theory

Teacher knowledges framework

In his groundbreaking work, Lee Shulman delineated the sources of teacher knowledge in instruction and the importance of the three interacting domains of content knowledge, pedagogical knowledge, and pedagogical content knowledge.[3] These three domains of teacher knowledge can be conceptualized simply as what, why, and how. Content knowledge is the storage and organization of subject matter—the what—in the mind of the teacher. Pedagogical knowledge is the reasoning and rationale—the why—for providing information in certain ways, formats, or utilizing certain approaches when teaching. Pedagogical content knowledge is the transformation of content knowledge using pedagogical knowledge—the how—into representations understandable and appropriate to the learner. Shulman stated that expert knowledge in content matter is equally as important as expert knowledge in pedagogy. He further reasoned that in an instructional context these domains of knowledge should not operate in isolation; expert content knowledge is as useless pedagogically as skill without content understanding. The simultaneous intersection of these two domains in concert—pedagogical content knowledge—is the key knowledge necessary for effective teaching (Figure 1).

The expert blind spot theory

As briefly defined earlier, the expert blind spot effect is the phenomenon wherein content experts tend to represent their advanced knowledge through internal expert schema rather than what may be appropriate for a novice learner. A major assumption (albeit empirically supported) of this perspective is that individuals with expertise are not necessarily more intelligent or wield greater intellectual resources; instead they have acquired specifically organized knowledge from long-term practice. Experts also represent problems and information at a deeper level using these advanced organizing principles and expert heuristics. The expert blind spot theory extends Shulman’s initial conclusion that expert content knowledge is instructionally useless in the absence of pedagogical knowledge. It is not just useless without pedagogical knowledge, it is detrimental to learners due to the tendency towards inappropriately advanced representation of the content. In instances where an individual’s content knowledge is vastly superior to the individual’s knowledge of pedagogy, content knowledge eclipses the domain of pedagogical content knowledge in instructional decisions (Figure 2). While this line of logic describes the potential negative consequence of content expertise, of further paramount importance is the finding that teachers are completely unaware that this occurs in their instruction; hence, the blind spot. Mitchell Nathan and Anthony Petrosino, major researchers in this field, summarize this overall perspective:

We do not contend that expert-levels of content knowledge are bad for teaching—on the contrary, it is clearly crucial. Rather, we present evidence suggesting that advanced subject matter knowledge without concomitant knowledge of how novices actually learn and develop within a content area can lead to views of instruction that align more closely with the organization favored by the subject matter experts and the domain of the discipline than the learning needs of students.[4]

II. Implications for the Guitar Pedagogue

This theory has been researched in a classroom teacher context with an emphasis on core subject areas. But, because of the internal cognitive nature of the expert blind spot effect, it has repercussions for guitar pedagogues regardless of the context of instruction. In essence, this is not just a classroom phenomenon; this is a phenomenon that occurs in the minds of teachers regardless of where they teach, who they teach, and what they teach. Guitarists in instructional positions inherently possess expertise in the fields of music, guitar, and performance, and are therefore vulnerable to the effects of the expert blind spot. Even if guitar pedagogues have considered their approach, methods, instruction, and pedagogy, and find no faults of this nature, they may still be affected because…

Aware or not, it truly is a blind spot

The expert blind spot can be compared to an actual neurological-visual blind spot in every person’s eye. This visual blind spot occurs due to a gap in visual receptors on the retina where the optic nerve exits the eye. Objects in the visual field that fall into the blind spot are not perceived because they are automatically “filled-in” by neurological processes. V. S. Ramachandran states that “the surprising thing is that even if you close one eye and glance around the room, you are still not aware of the blind spot unless you carefully look for it. Again, you don’t notice the gap because your visual system obligingly fills in the missing information.”[5] The key to this comparison is the unawareness of this visual blind spot due to the automatic “filling-in” by neurological processes. Further, awareness of the visual blind spot did not affect its functioning; awareness of the blind spot does not restore vision to it. Likewise, unawareness of a pedagogical blind spot is due to the automatic “eclipsing” of cognitive processes, wherein expert content knowledge schema “fill-in” the gap in pedagogical content knowledge. Even if the pedagogical blind spot is known, it will still act in the same fashion.  Illustrating this concept, a series of studies explored the effects of expertise on predictions of novice performance.[6] They found that experts severely underestimated the difficulty that novices face. Even when participant experts were made aware of their tendency to underestimate novice difficulties (their pedagogical blind spot) through cognitive debiasing methods (recalling their own experience, being presented with a list of potential difficulties novice would face), there was no effect on the accuracy of the experts’ predictions. In essence, these findings showed that awareness of the blind spot did not mediate its negative effects. Equally disconcerting is the finding in these studies that there may be a correlation between level of expertise and vulnerability to the blind spot. Essentially, the higher the level of expertise possessed by an expert, the more severe the effect of the blind spot.

Guitar performance as expert representations

As stated earlier, the founder of the teacher knowledges framework, Lee Shulman, as well as research literature of the expert blind spot state that, instructionally, content expertise is useless without interacting pedagogical knowledge. In the world of guitar performance, a serious rebuttal could be made against this assertion. It could be argued that a truly expertly performed guitar recital could be extremely educational, edifying, and a model performance for novices in the audience. One would be hard-pressed to find a guitarist who did not reflect on the performance of another to improve his or her own. 

Unfortunately, this practice lies at the center of the expert blind spot: expert representations presented to novices. Experts do indeed learn well from the model performance of others. This is due to their advanced organization and hierarchy of knowledge that may be largely automated. Through this, experts can see, examine, and understand several aspects of a performance simultaneously and transfer that analysis to their own performance. “Experts bring their activated schemas to the process of constructing mental representations of a situation or task. They may not need any additional instructional guidance because their schemas provide full guidance.”[7] The novice, however, neither has the cognitive capacity nor the knowledge to attempt this. The novice will perceive those aspects of the expert performance that are readily familiar, perhaps extending existing scaffolds and schema, but more likely perpetuating and reinforcing novice conceptions. Though the novice guitarist may begin to imitate the expert performance quite well, that is all that it is: imitation without understanding, replication without thought. This idea outlines a conception parallel to the expert blind spot effect: the expertise reversal effect, wherein the methods by which novices learn are inappropriate for experts and vice versa.  Although this is a separate strand of “expertise” literature, the assertion is identical—expert representations are inappropriate for the instruction of novices without proper guiding pedagogy.

The analysis and application of information from an expertly executed guitar performance is an example of high-element interactivity material.[8] High-element interactivity material imposes a hefty cognitive load due to the interacting nature of the elements that cannot be processed simultaneously without sacrificing understanding (in the novice guitarist). A guitar performance is an amalgamation of several simultaneously interacting elements: pitches, harmony, tempo, timbre, tone, color, dynamics, articulation, technique, interpretation, style, form, themes, etc. The implication outlined here is not that expert guitar performances are instructionally inappropriate, but like any analysis and application endeavor, they must be framed appropriately based on the novice’s current knowledge, scaffolds, and schema; pedagogy must drive the use of modeled expert performance. When a teacher breaks down the elements of the performance for novice understanding, then appropriate pedagogy—instructional guidance of the novice—is reintroduced. 

Research has provided powerful evidence that understanding of highly complex material is better achieved by a two-phase, isolated-interacting-elements learning approach.[9] In the first phase, element-interactivity is artificially reduced—presenting material as isolated elements or guiding novices to isolate interacting elements. In this way novices may construct appropriate individual schema. In the second phase, all information is reintroduced, the assertion being that the previously constructed individual schema will facilitate learning of the simultaneous-interacting material.

When perceived in this manner, the appropriateness of the masterclass model for an audience becomes apparent. Perhaps this is why the masterclass model has persisted as a dominant form of impactful study. In the ideal, it is an effective use of content expertise combined with pedagogy.  Not only is a masterclass a presentation of performance, but it is a pedagogical consideration of the performance. Elements that may have interacted during the performance are isolated for focused practice or intervention. But, according to the two-phase model, the learning process should conclude with a reintroduction of the high-element interactivity material—the guitar performance. Therefore, the implication for the masterclass model is that the masterclass should conclude with yet another performance of the material for the benefit not only of the participant but for the audience. This practice is not necessarily standard in the masterclass model, but expertise research suggests that it should be. 

Instructional explanations as expert representations

Instructional explanations are purposefully provided with the goal of teaching a certain concept in a certain way. They can be thought of as pedagogical decisions aimed to provide answers to questions that are implicitly or explicitly posed. The goal and character of instructional explanations depend on the previously acquired skills and knowledge of the learner. Absolute novices, in the early phase of a skill acquisition, need instructional explanations that introduce basic concepts and new knowledge or skills. This simplistic approach precludes the use of expert representations during the initial phase of learning. Beyond the initial phase, novices may develop faulty knowledge, misconceptions, or encounter difficulties reconciling the knowledge and skills. In this stage, novices may be introduced to more complex or expert representations but only as a means to restructure their misconceptions or to improve their problem-solving skills with regard to the concept at hand. This use of a more expert representation is pedagogically driven based on the novice’s level of skill acquisition and prior knowledge. Interestingly, as a novice approaches the graduation threshold past “noviceship,” the pedagogical usefulness of instructional explanations wanes. In the final phases of skill acquisition, practice and application is the primary pedagogy, while instructional explanations are supplemental to this process.

Effective instructional explanation-use is not only pedagogically guided by the learner; it is also guided by the context and format of instruction, the medium of presentation, and the instructional epistemology of the teacher. The nature of guitar instruction and music pedagogy in general lends toward constructivist approaches to instruction. Constructivist methods of instruction place emphasis on the facilitation of learning by the teacher rather than direct, didactic instruction.  Through this approach, ultimately, learners are responsible for engaging and achieving learning on their own.[10] In this philosophical orientation, instructional explanations are considered a supplement rather than the primary means of instruction. In specific contexts, such as the tutoring model (identical to the private lesson model of guitar instruction), interactive methods to instructional explanations are shown to be effective, encouraging learners to construct their own explanations rather than rely on the tutor’s explanations.[11] These learner-generated explanations are also produced in the processing of written explanations because the learner can return to the material repeatedly to generate more meaningful schema for understanding.[12]

Guitar pedagogues can and should take advantage of the adaptive nature of verbal explanations—adjusting explanations based on the novice’s level and prior knowledge while also giving ample opportunities for novice guitarists to attempt to produce self-generated explanations and understanding of content. Rather than introducing a new concept with an explanation, the instructor should allow students to discover concepts (or better, guide students toward discovering concepts) with the instructor facilitating development through explanations after discovery. In this way, scaffolds are self-generated in the novice that can then be broadened, reinforced, and developed by the instructor’s explanations. Further, when instructional explanations are student-based and student-reactive, they can bypass the expert blind spot effect (an instructor-generated, inappropriately expertise-laden explanation, in this case).

Music notation as expert representations

Specific and almost exclusive to the field of music instruction is the fact that the predominant means of representation in our craft—music notation, scores, sheet music, and music vocabulary—is an expert representation almost immediately introduced to novices in most instructional situations. Even if a guitar score is not necessarily virtuosic in nature, an expert guitarist will implicitly process information from the score that is not apparent to the novice (much like literary subtext). The expert’s activated schema simultaneously and automatically engage the score in a very different way than a novice guitarist. For instance, even before reaching the notation, cues from the title, composer, and era will be taken into consideration for style, interpretation, and performance; elements often overlooked by a novice. Another simple consideration for the novice would be the key signature. But to the expert guitarist, a key signature will illicit an automatic retrieval of multiple internal schema such as a mental fretboard map of the key, common chords and formations in the key, practical positions, and component finger patterns (among many possible other schema). Because guitar music will be processed differently by the student than by the teacher, it is important for the guitar pedagogue to treat it as an expert representation. It is then the responsibility of the instructor to frame facilitative instruction of a piece appropriately to the skill level and knowledge of the novice and take a constructivist approach to the discovery of skills in the piece.

Light at the end of the tunnel: A positive impact of expert representations for novices

Despite the negative repercussions of the expert blind spot, there is light at the end of the tunnel.  Abstract and advanced concepts as presented by expert instruction facilitate more advanced schema in the novice. And while these advanced schemas initially hinder understanding and performance, the transfer of knowledge to another task within the same domain is facilitated by them, resulting in enhanced understanding and performance.[13] For example, explaining a section of arpeggios in a Bach piece as a figured-bass chord progression (as compared to simply demonstrating or explaining each arpeggio) will slow the learning process in novice guitarists as they process the multiple complex elements and attempt to construct schemas. But, when they encounter similar musical material in other repertoire, they will have a deeper and more abstract understanding that will facilitate faster learning of the new material and a better performance. 

While this phenomenon could be the unraveling of the expert blind spot, essentially revealing that in the long term expert representations are positive, there is a caveat: constant and pervasive overuse of expert representations in instruction will overwhelm the novice. In the practical realm, this leads to confusion, burnout, and general discouragement. Use of expert representations to this specific end—the transfer of knowledge between tasks and situations within a domain—must be purposeful and intentional; it must be the explicit goal of the instruction provided rather than a side-effect of the lack of pedagogical knowledge. 

Mitiating the expert blind spot effect

Awareness of the expert blind spot alone is not enough to mediate its effects. Deliberate and purposeful actions must be taken to minimize the impact of the blind spot in instruction.  Because the expert blind spot is a metaphor for an actual visual phenomenon, the following recommendations for mediating it are presented in similar metaphorical language.

• Add an eye. The visual blind spot in your eye only appears when one eye is closed.  When both eyes are open they compensate for each other, and there are no blind spots in the visual field. Equally, adding another perspective to your instruction can both reveal and compensate for your expert blind spot. Have a colleague observe your teaching or sit in on a lesson. It could be even more effective if that colleague has considerable pedagogical knowledge but not the same content knowledge as you (another instrument or department). Make sure to receive feedback and specific recommendations from them.
• Balance your prescription. According to the teacher knowledges framework, there are only two knowledges: content and pedagogical. It is the interaction of these two that create the third and most important teacher knowledge: pedagogical content knowledge (Figure 1). As an expert of guitar your vast content knowledge can easily overwhelm your pedagogical content knowledge leading to the expert blind spot effect. An elegantly simple intervention is the development and broadening of your general pedagogical knowledge. Topics to study include human cognition (how people learn, attain skills, and retain information), constructivism (the educational philosophy, ontological stance, and approaches to effective instruction), teaching models, and even classroom management theories.
• Close your expert eyes. In the spirit of a constructivist approach, the best way to introduce new concepts is through student discovery, self-generation of concepts, and reinforcement through application. This process requires expert teachers to take a facilitative role and shelve their expertise in the early phases of concept/skill acquisition. Place the responsibility of learning on students and guide their progress, shape their understanding, and eventually you can reopen your expert eyes to polish their development.

III. Conclusion

It is important that we accept that in our field one of our greatest strengths, expertise, is also a double-edged sword. It may be found that the expert blind spot effect is the root of many of the instructional issues that guitarists face, both students and teachers. Insight into its existence should be an impetus for guitar educators to take efforts to mediate their own expert blind spot.  And while this article focused on instruction, these concepts can be furthered to include reform of guitar materials, curricula, and methods. These efforts could continue to improve guitar pedagogy and remove one more challenge faced by the guitar pedagogue.

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[1] Slava Kalyuga et al., “The Expertise Reversal Effect,” Educational Psychologist 38, no. 1 (2003): 27.

[2] Mitchell J. Nathan, Kenneth R. Koedinger and Martha W. Alibali, “Expert Blind Spot: When Content Knowledge Eclipses Pedagogical Content Knowledge,” in Proceedings of the Third International Conference on Cognitive Science (Beijing: USTC Press, 2001), 45.

[3] Lee S. Shulman, “Those Who Understand: Knowledge Growth in Teaching,” Educational Researcher15, no. 2 (1986): 9.

[4] Mitchell J.Nathan and Anthony Petrosino, “Expert Blind Spot among Preservice Teachers,” American Educational Research Journal 40, no. 4 (2003): 906.

[5] Vilayanur S. Ramachandran, Sandra Blakeslee and Neil Shah, Phantoms in the Brain: Probing the Mysteries of the Human Mind (New York: William Morrow, 1998), 90.

[6] Pamela J. Hinds, Michael Patterson and Jeffrey Pfeffer, “Bothered by Abstraction: The Effect of Expertise on Knowledge Transfer and Subsequent Novice Performance,” Journal of Applied Psychology 86, no. 6 (2001): 1232.

[7]Kalyuga et al., 24.

[8] Edwina Pollock, Paul Chandler and John Sweller, “Assimilating Complex Information,” Learning and Instruction 12, no. 1 (2002): 62.

[9] Ibid.

[10] J. G. Brooks, “Transforming Knowledge of How People Learn into Meaningful Instruction,” Handbook of Educational Theories, B. J. Irby et al., eds. (Charlotte, NC: Information Age, 2013): 271.

[11] Michelene TH Chi et al., “Learning from Human Tutoring,” Cognitive Science 25, no. 4 (2001): 517.

[12] Joerg Wittwer and Alexander Renkl, “Why Instructional Explanations Often Do Not Work: A Framework for Understanding the Effectiveness of Instructional Explanations,” Educational Psychologist 43, no. 1 (2008): 52.

[13] Hinds et al., 26.