In this issue of Topics in Language Disorders, the authors address discourse intervention across the life span. The discourse demands for preschoolers are very different from those experienced by school-aged children and adolescents or adults. To make matters more complex, discourse is not a unified construct but, rather, consists of various levels of representation including the surface code, textbase, situation model, pragmatic communication, and discourse genre (Graesser, Millis, & Zwaan, 1997; Kintsch, 1998).

Speech-language pathologists and other language specialists often are most comfortable working on surface code skills that include the words and sentence structures used to convey meaning. These make important contributions to discourse, but they are not all there is. For example, consider the sentences, "The hummingbird's tiny wings were invisible to the naked eye, as he fluttered above the flower. After obtaining what he had come for he disappeared as quickly as he had appeared." The main clause in the first sentence contains an elaborated noun phrase that describes the hummingbird's wings ("The hummingbird's tiny wings"). The adverbial clause, "as he fluttered above the flower," indicates the condition under which the wings were invisible. To understand this sentence, one must understand the temporal relationships between "as" and "were invisible" and the deictic coherence of the fact that "he" refers to the hummingbird and not the person who was observing the hummingbird. In addition to using syntactic knowledge to build an understanding of this utterance using surface code information, the individual must also possess semantic knowledge related to the meanings of "invisible" and "naked eye."

Discourse also involves the textbase, which refers to the propositions or meaning units conveyed by the surface code. In the aforementioned example, propositions generated by the listener or reader may include "the hummingbird had wings," "the wings were small," "the wings were invisible," "the bird was fluttering," "the bird was above the flower," and "the wings were invisible during the time at which the bird was fluttering above the flower."

The situation, which is sometimes termed mental model, is another level of discourse and contains information about the topic of a paragraph that is revealed through a causally connected chain of events as they develop. In the case of the hummingbird passage, the mental model encompassed an agent (a hummingbird), a setting (above the flower), actions (hummingbird fluttered, got what he came for, disappeared quickly), and events that were inferentially suggested (the wings were not really invisible, but very small, he went to the flower to get food, he got food, and he was very fast, hard to see).

The pragmatic communication level, which is also part of discourse use, signifies the interchange between the speaker and the listener, or the reader and the writer, who in this example may be a bird expert talking to a layperson who knows little about the hummingbird as he exists in nature. The last level is termed discourse genre and is used to describe the category of discourse. Two common types of discourse are narrative and expository or informational discourse (Graesser, Person, & Hu, 2002).

A narrative is a series of events connected in a logical order and is typically produced as a monologue (Boudreau, 2000). Within the narrative genre are scripts (e.g., sequence of events as part of routine experience), personal events (e.g., sequence of events to describe what happened during a visit to the library), and fictional stories (e.g., sequence of events motivated by goal plans). Using the aforementioned hummingbird example, a script might be told about the habitual rounds the bird makes as he goes about his task of foraging for nectar in flowers. A personal event story might be told about rescuing an injured hummingbird, and a fictional story might be composed about a hummingbird who gets lost and has to find his way back home.

These different types of narrative discourse are used to share and relay information in preschool and kindergarten and later during early school-age to accomplish various academic tasks as outlined in the Common Core State Standards (CCSS; National Governors Association Center for Best Practices & Council of Chief State School Officers, 2010).

By fourth grade, the CCSS recommend that students read and receive literacy instruction in an equal (50/50) proportion of informational and narrative texts (National Governors Association Center for Best Practices & Council of Chief State School Officers, 2010). The proportion of informational to narrative texts increases to 70/30 by Grade 12. Informational discourse typically contains unfamiliar concepts and vocabulary, presented in an unfamiliar text structure (e.g., cause-effect, problem-solution). These factors cause a significant burden on working memory, making informational discourse particularly difficult to comprehend. If students are to be successful in developing comprehension and compositional skills in the informational genre, they will require evidence-based instruction that focuses on text structure, specific linguistic targets (referential, causal, temporal, spatial, adversative, logical, and deictic coherence relations), and higher level language skills (e.g., comprehension monitoring). As part of this process, students are expected to learn to process academic language in textbooks, as well as in storybooks. In written text, knowledge of coherence relations such as headers, subheaders, highlighted words, signaling devices (topic sentences), and other organizational and paragraph conventions is also required and must be explicitly taught (Graesser, McNamara, & Louwerse, 2003).

Clearly, the levels of discourse representation discussed earlier (surface code, textbase, situation model, pragmatic communication) are easier for children and adults because the events are more closely related to things that occur in their daily lives. It is more difficult for most students to process information at each of these levels in the informational genre, particularly when there is a paucity of world knowledge available for constructing a situation model or engaging in pragmatic communication about the topic. Interestingly, as individuals age, the importance of sharing and relaying information becomes the primary function of discourse interactions, shifting once again to narrative over informational discourse.

This forum is unique because discourse intervention is discussed from a life span approach, spanning preschool through adulthood. In the first article, the importance of oral narratives as a means of sharing and relaying information and for use in early academic tasks is emphasized in a review of preschool narrative-based language intervention studies. The authors (Petersen & Spencer, 2016) focus their discussion on treatment of culturally and linguistically diverse preschoolers and the importance of personal-themed stories as a means for strengthening comprehension and use of structure and academic language abilities.

The next article (Gillam & Gillam, 2016) addresses the importance of the development and stabilization of cognitive and linguistic skills necessary for academic success in the school-age years. It emphasizes the implications of training specific metacognitive skills necessary for students to integrate oral and written discourse information with existing knowledge for recalling, paraphrasing, retelling, summarizing, composing, and learning new information in the narrative genre.

The next two articles address topics related to oral and written knowledge and skills in the informational discourse genre. The first of these two articles (Danzak & Arfe, 2016) highlights microstructural and macrostructural text features and the impact of language-specific persuasive writing skills displayed by bilingual high school students learning English, secondary to Italian. The article highlights the role of language-specific constraints, as well as cross-language transfer of discourse skills in written composition. The next article (Ward-Lonergan & Duthie, 2016) presents a comprehensive review of intervention techniques, strategies, and approaches to facilitate proficiency in literacy by improving skills in expository (informational) reading comprehension.

The last two articles address discourse topics in older populations. The first of the two (Cannizzaro, Stephens, Breidenstein, & Crovo, 2016) is an exploratory, quantitative, observational study of brain function during naturalistic discourse processing and production in non-brain-injured adults. In this study, neuroimaging technology is used to examine brain function during narrative discourse tasks performed by typical adults. This study highlights potential neural underpinnings of discourse processing in adults to potentially inform treatment of those with impairments. The final article (Milman, 2016) provides a review of studies of integrated discourse treatment approaches that incorporate training on isolated linguistic topics within discourse-level contexts for older patients with aphasia.

Discourse is a critical tool for communicating and sharing events from our daily life, as well as for conveying and learning new information. There is a focus on narrative discourse early in people's lives with a deliberate shift toward informational discourse in later elementary and adolescence, primarily driven by the central role of academics during that time. Interestingly, there is a return to predominance of narrative discourse in adulthood, as interests and daily experiences shift back to the desire to communicate and share events with others, although some adults express a preference for reading informational texts over novels. As Issue Editor, my goal is that the articles in this forum will be useful for clinicians working with patients at different points along the developmental continuum who will face a variety of discourse challenges in their daily lives.

-Sandra Gillam, PhD

Utah State University, Logan

Issue Editor

[email protected]

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