Biological Processes Underlying Written Language Acquisition
Stephen Hooper, Ph.D., Departments of Psychiatry and Pediatrics, and The Clinical Center for the Study of Development and Learning, Carolina Institute for Developmental Disabilities, University of North Carolina School of Medicine
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Of or relating to processes of the brain such as awareness, perception, reasoning, memory and judgement.
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Model based on or calculated through theory rather than experience or practice.
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A collection of brain processes responsible for planning, cognitive flexibility, abstract thinking, initiation of appropriate actions and inhibition of inappropriate actions.
The understanding that letters and combinations of letters are the symbols used to represent the speech sounds; and that there are systematic and predictable relationships between written letters and spoken words.
Involves complex behaviour involving self-generated plans and flexible adaptation to the changing demands of a task.
Refers to the support that is given to students in order to facilitate learning. This support may occur as immediate, specific feedback that a teacher offers during student practice (e.g., giving encouragement or cues, breaking the problem down into smaller steps, using a graphic organizer, or providing an example). Scaffolding may be embedded in the features of the instructional design (starting with simpler skills and building progressively to more difficult skills).
Refers to the memory system used to store and actively manipulate temporary information for use; can also be called short-term memory.
Relating to the nature, structure, and variation of language.
The conventions and rules for assembling words into meaningful sentences; syntax varies across languages.
An ability to take in, store, process and use information in an orderly way.
Processes such as reasoning and problem solving.
Pertaining to the perception of the spatial relationships between objects in one's field of vision.
An individual's ability to identify and manipulate the sounds in a language.
Movements that require a high degree of control and precision. These may include drawing shapes, writing, cutting with a scissors, using eating utensils.
Having or involving several dimensions or aspects.
This is a meta-cognitive process in which students actively think about how they are learning or understanding the material, activities, or reading.
A region of the brain responsible for the planning and coordination of complex movements such as those requiring two hands.
A region of the brain responsible for generating the neural impulses controlling execution of movement.
A brain region located in the back of the head between the cerebrum and the brain stem. It plays an important role in the integration of sensory perception, coordination and motor control.
A fold or ridge on the surface of the brain involved in spatial orientation and word representation.
A structure located deep within the brain whose functions include perception, motor control, self-awareness, cognitive functioning, and interpersonal experience.
A brain region located near the top of the frontal lobes and along the walls that divide the left and right hemispheres. It is involved in a wide variety of cognitive and emotional functions. It plays a key role in the brain's ability to process particularly complex and challenging cognitive tasks.
Situated on both the back and the side.
A region located at the front of the brain that has been implicated in planning complex cognitive behaviors, personality expression, decision making and moderating correct social behavior.
A part of the parietal lobe of the brain which integrates information from different sensory modalities and plays an important role in a variety of higher cognitive functions.
The sound or verbal/visual language memory system used for holding and manipulating information while various mental tasks are carried out.
An area in the brain that helps regulate emotion and memory.
A set of brain structures including the hippocampus, amygdala, anterior thalamic nuclei, and limbic cortex, which support a variety of functions including emotion, behavior, long term memory, and olfaction.
Studies that use working hypotheses that are testable using observation or experiment.
A region in the brain in the upper part of the parietal lobe.
An area at the front of the brain, located in the frontal lobe; thought to be responsible for speech production.
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A region in the brain associated with verbal memory.
A subdivision of the brain that serves as a relay station to and from the cerebral cortex and functions in arousal and the integration of sensory information.
The region of the frontal lobe of the brain that is involved in decision making and other cognitive processes; also has a role in emotion.
The lower region of the right frontal lobe, above the orbit of the eye; specializes in higher cognitive function.
A structure in the brain positioned above the cuneus and located in the parietal lobe. It is believed that it contains a sensory-based map of one's own body.
The lower region of the right temporal lobe; involved in auditory processing.
A region of the brain thought to be involved in high-level auditory processing.
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A fold or ridge on the surface of the brain that plays a key role in reading and visual word recognition.
Any of various regions of the cerebral cortex.
A set of specialized cells that serve a specific function (e.g., visual system).
Of or pertaining to the development of neurological pathways in the brain.
The National Center for Education Statistics (2003) in the U.S. reported that only about 28% of fourth graders could write at a proficient level or above (i.e., create an effective response to the task in form, content, and language, demonstrate an awareness of the intended audience, use effective organization appropriate to the task, use sufficient elaboration to clarify and enhance the central idea, etc.), 58% wrote at a basic level (i.e., demonstrate appropriate response to the task in form, content, and language, use some supporting details, demonstrate organization appropriate to the task, and demonstrate sufficient command of spelling, grammar, punctuation, and capitalization to communicate to the reader), and 14% wrote below the basic level. These data are compelling in that they indicate the national significance of writing problems in elementary education. In this regard, the development of writing skills in students presents a significant challenge for educators, particularly in this day of high-stakes testing and heightened accountability. While our understanding of the underlying cognitive
components of reading has proliferated over the past 20 years, we have only begun to understand the basic neurocognitive
factors that may underlie the development of written expression in the formative elementary school years (Edwards, 2003; Graham & Harris, 2005).
Key Research Questions
Recent Research Results
What theoretical models guide the study of the neurobiological processes underlying written language acquisition?
What theoretical models guide the study of the neurobiological processes underlying written language acquisition?
What neurocognitive functions are associated with the acquisition of written language and how do they affect writing at different developmental time points?
What neurological systems contribute to the development of written language?
There have been several theoretical models proposed to describe the cognitive functions involved in written expression (e.g., Kellogg, 1996), with these models generally invoking various language, short-term
and long-term memory
, and executive functions
. The model proposed by Hayes and Flower (1980), and subsequently revised by Hayes (2006), has been one of the most influential in the field of written expression; however, the various subcomponents of the current Hayes model are unconstrained, particularly from a developmental perspective, and their interactions over time remain relatively unknown.
A Developmental Model of Written Expression.
A more contemporary model of written expression is based on the work of Juel (1988) – the Simple View of Writing
. Berninger and colleagues (Berninger & Amtmann, 2003; Berninger & Winn, 2006) have expanded this model into the Not-So-Simple View of Writing
which includes three major components: transcription (for handwriting, letter production, spelling, and word production); executive functions (for planning, monitoring, and revising); and text generation. The latter component, text generation, occurs at the word, sentence, and text levels; consequently, automatic production of letters is necessary, but not sufficient, as spelling words via the alphabetic principle
and related orthographic elements are necessary for writing proficiency (Jones & Christensen, 1999). In addition to moving from picture processing and production to writing processing and production (Adi-Japha & Freeman, 2001), beginning writers have immature self-regulation functions
, thus requiring considerable teacher modeling and scaffolding
(Berninger & Richards, 2002). Beginning writers at this stage also benefit from integrated reading-writing instruction, although it is important to note that proficient reading also is not sufficient for competent written expression (Abbott et al., 1997).
According to this developmental model, lower level neuropsychological functions are related directly to initial writing skills, and they appear to have their largest impact on the transcription subcomponent of the writing process. The writing of early elementary school students will be constrained by factors related to graphomotor output (e.g., letter formation), memory for letters and words, emergent working memory
capacity, and linguistic
capabilities (Berninger & Winn, 2006). By the middle of elementary school many, but not all, children have sufficient transcription skills, and their writing will progress with increased emphasis placed on text generation and executive functions. Explicit instruction aimed at both the syntax
and discourse levels (e.g., content, organization, clarity, etc.) also is required (Graham & Harris, 2000; Graham et al., 2001). Further, developing writers continue to need explicit instruction in the planning (De La Paz, 1997; Graham & Harris, 2000) and reviewing/revising (e.g., Graham, 1997) components of composing as most students are not fully self-regulated writers at this developmental period (Graham & Harris, 2003). In general, the Not-So-Simple View of Writing Model
postulates that neuropsychological, linguistic, and related cognitive constraints may be recursive throughout the development of the writing process, but that each of these constraints will exert relatively greater influence at different points in the developmental process.
What neurocognitive functions are associated with the acquisition of written language and how do they affect writing at different developmental time points?
Over 15 years ago Levine et al. (1993) theorized about the importance of a variety of neuropsychological functions in the writing process (e.g., memory, attention, graphomotor output, sequential processing
, higher-order cognition
, language, visual-spatial
functions); however, no data were available to support when or to what degree these functions influenced the writing process. At the same time, Abbott and Berninger (1993) noted that oral language/verbal reasoning, including such functions as sentence memory, word finding, phonological processing
, and reading, contributed to composition fluency. Berninger and Rutberg (1992) also described the importance of fine-motor
planning and control to the development of writing in early elementary grade children.
More recent studies have begun to document the cognitive abilities associated with "expert" writers (Berninger et al., 2002; Gregg & Mather, 2002; Hayes, 2000; Torrance, Fidalgo, & Garcia, 2007). Recent work by our research group with fourth and fifth grade students with and without writing problems documented not only working memory deficits, but broader memory problems (Hooper et al., 2009) and executive dysfunctions (Hooper et al., 2002) that can undermine the writing process. Our group also has examined the multidimensionality
manifested in elementary school students with and without writing problems (Hooper et al., 2006; Sandler et al., 1992; Wakely et al., 2006), with results suggestive of the presence of multiple written language subtypes in the regular education setting—including both typical and atypical cognitive-linguistic profiles. Consistent with cognitive components described in the Not-So-Simple View of Writing
, these studies collectively have shown the importance of specific linguistic factors (e.g., semantics, grammar), along with academic functions such as reading and spelling, as key dimensions of written expression.
Perhaps one of the most studied neurocognitive functions in the area of written language is working memory (Lea & Levy, 1999; McCutchen, 2000). Working memory is important to written expression because it underlies the active maintenance of multiple ideas, the retrieval of grammatical rules from long-term memory, and the recursive self-monitoring
that is required during the act of writing (Kellogg, 1999). Working memory contributes to the management of these simultaneous processes, and a breakdown may lead to problems with written output (Levy & Marek, 1999). McCutchen (2000) noted that poor writers typically have reduced working memory capacity when compared to good writers, and Swanson and Berninger (1996) reported that working memory has both general and domain-specific contributions to the writing process.
What neurological systems contribute to the development of written language acquisition?
Based on the neurocognitive functions that purportedly contribute to the development of written language, it has been speculated that there are many more brain areas involved during the act of writing than for other academic domains (Hale & Fiorello, 2004). Based on the Not-So-Simple View of Writing
, it is likely that different brain systems are primarily involved at different developmental periods. To date, however, there are few studies that have identified the various neurological systems contributing to the development of written language.
Berninger and Richards (2002) provided a list of possible brain structures that could be involved in various writing functions. For example, they noted that the supplementary motor region
, primary and secondary motor areas
, and anterior cerebellum
were brain regions that could be involved in graphomotor output (i.e., writing), and that the supramarginal gyrus
, and anterior cingulate
were key structures important to the phonologic-orthographic (i.e., sound-writing) component. For written expression, they postulated the involvement of the left dorsolateral prefrontal cortex
for the goal setting, planning, monitoring, and revising functions; the prefrontal cortex, left inferior parietal cortex
, and left supramarginal gyrus for phonological working memory
; the hippocampus
for the long-term memory aspects of written expression; and aspects of the limbic system
for the motivational and emotional components of written output.
At present, empirical studies
have begun to verify these structure-function relationships in written expression. Initial lesion studies (i.e., studies of patients with deficits that arise following a brain injury) implicated the superior parietal lobe
and middle frontal regions
as critical to intact written expression (Roeltgen, 2003). In addition, neuroimaging studies
have begun to demonstrate linkages between various fine-motor or graphomotor movements and various brain structures such as the premotor cortex, supplementary motor cortex, cerebellum, basal ganglia
, left temporal cortex
, left anterior cingulate, and orbitofrontal cortex
(Deus, Junque, Pujol, Vendrell, Vila, & Capdevila, 1997; Filipović, Papathanasiou, Whurr, Rothwell, & Jahanshahi, 2008; James & Gauthier, 2006; Jenkins, Brooks, Nixon, Frackowiak, & Passingham, 1994; Katanoda, Yoshikawa, & Sugishita, 2001; Menon & Desmond, 2001; Nicholson et al., 1999; van Mier, Temple, Perlmutter, Raichle, & Petersen, 1998; Richards et al., 2009). For example, Richards et al. (2009) showed that sequential finger movements were associated with key brain regions deemed important to written expression in good but not poor elementary school writers. These brain regions included the left superior parietal, right inferior frontal orbital
, right precuneus
, right inferior temporal
, and left inferior temporal
areas. Additionally, activation in these regions was significantly correlated with handwriting, spelling, and composing. In one of the few studies where participants were required to write (i.e., sentences from dictation), Menon and Desmond (2001) used functional magnetic resonance imaging (fMRI)
to show the left superior parietal lobe and left inferior frontal gyrus
to be key brain regions involved in written output. An exciting line of research also has begun to examine the neurological substrates involved in higher-order writing skills. Using fMRI, Berninger et al. (2009) demonstrated greater activation in prefrontal cortical regions
associated with working memory during an idea generation task. Finally, Pugh et al. (2006) noted that there likely is a high degree of overlap between the neural systems
serving both oral and written language and to some extent, reading (Caplan, 2004), and that the study of these associated systems will be important for increasing our understanding of the neurological bases of written language. Taken together, these findings have begun to target the basic neural systems important to written expression.
The study of the neurobiological foundations of written language acquisition is an exciting area of scientific inquiry. Over the past two decades significant advances have been made with respect to our understanding of written language from a cognitive perspective, particularly with respect to neurodevelopmental
models that parallel cognitive growth and development. Future studies should continue to examine the various nuances of these models and how they relate to specific evidence-based interventions for children struggling with written output. Additionally, a downward extension of these models to preschool populations may provide critical knowledge with respect to early intervention efforts. Similarly, the field has begun to make gains in our understanding of the neurological substrates involved in written expression. Additional neurologically-based studies of impaired, at-risk, and typical writers at different developmental time points will also be useful in advancing this emergent knowledge-base. Finally, as evidence-based educational interventions begin to surface, perhaps by employing subtype X treatment methodology (Hooper et al., 2006), it will be interesting to determine if such interventions can modify brain activation patterns in conjunction with improvements in written expression.
This encyclopedia entry has provided an overview of the basic biological processes that contribute to the acquisition of written language skills. An important neurodevelopmental model of written language was discussed and its associated neurocognitive abilities detailed. Additionally, the available neurological findings to date were noted, with a specific focus on the emergent neuroimaging findings. Although the basic notion of how written language skills develop remains somewhat elusive, the field has begun to assert findings that have increased our understanding of this critical output function, and future research efforts undoubtedly will further our understanding over the next decade.
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