Searching for the Grand Unifying Theory: Reflections on the Field of LD

A recent overview of the field of learning disabilities (Torgesen, 2004) laid out several issues that will likely consume the field for the foreseeable future, including problems of definition and etiology, differentiation of learning disabilities from other disabilities, and issues in identification and service delivery. There is little to disagree about here. My views on the future of the field are further informed and colored by my own research focus on social and cultural aspects of learning and motivation for individuals with disabilities and students in at-risk circumstances. Before describing this view of the future, it is useful to step back for a moment and briefly (and, admittedly, incompletely) characterize where the field has been. It has been approximately half a century since learning disabilities were first recognized in the United States. Throughout that time ubiquitous "paradigm wars" have been a prominent feature of the discourse surrounding the field (Andrews et al., 2000; Brantlinger, 1997). The early focus on remediation of visual/perceptual and visual/motor processing difficulties slowly gave way to the behaviorally rooted direct instruction approach targeting discrete, observable behaviors. In turn, the field was transformed with the advent of the "cognitive revolution." The focus on observable behavior gave way to trying to understand the internal cognitive processes underlying specific tasks from an information-processing framework. Later, affective factors were recognized as critical since it became evident that just because students were strategic and knowledgeable about how to successfully perform a task, it did not mean that they would do so. Psychometrics and psychological science formed the disciplinary foundation for much of this work. Much later in the development of the field, attention came to be paid to the observation that additional factors were necessary to gain a fuller understanding of learning disabilities. Loosely termed here sociocultural factors, they include student-related features such as language, culture, and socioeconomic status, and also non-student contextual factors such as the social organization of classrooms and the correspondence, or lack thereof, between classrooms and communities (Kalyanpur & Harry, 1999; Torres-Velasquez, 1999). The unique constellation of information structures and processes, motivational beliefs about oneself as a learner and knower, strategies and understandings of problems, and even the meaning of academics and schooling, has increasingly come to be understood as being mediated at least in part by sociocultural factors (Okagaki, 2001; Pintrich, 1999; Spencer, 1999). The focus on these factors has been driven at least in part by the astounding increase in population diversity in the country as well as by continuing concern over equity in service delivery, educational outcomes, and overrepresentation (Losen & Orfield, 2002; National Research Council, 2002). A Personal Perspective My own focus on social and cultural factors was not spurred by my doctoral training in special education (primarily from a cognitive orientation), but by newly uncovered (at the time, in the late 1970s) issues of overrepresentation of African American and Latino students due to prevailing assessment and classification practices (Mercer, 1973). At the beginning of the 1980s, investigations into assessment and classification procedures were considered to be of primary importance (Mercer, Rueda, & Cardoza, 1986; Rueda & Mercer, 1985). In my case, it soon became apparent that coming up with more accurate sorting measures and procedures to figure out a more correct or accurate "box" was not the most critical issue. Not only did this focus not provide guidance on how to address the initial problem (low achievement), it became evident that early reading and literacy seemed to be the root of most early achievement problems and referrals (Lyon, 1985), especially for students from specific ethnic/racial groups (African American and Latino), SES groups (low), and language backgrounds (nonnative speakers of English). …