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anguage comprehension is one to be retrieved? Which type of information of the most automatic tasks that (phonological, grammatical, semantic) is humans perform. Yet it is also one used first, or has more influence over how a of the most complex, requiring person understands a text? What processes the simultaneous integration of do people use to correct themselves if they many different types of information, such as realise that they’ve misunderstood a text? Lknowledge about letters and their sounds, What if they don’t realise when this happens? spelling, grammar, word meanings, and For the most part, readers and listeners are general world knowledge. In addition, completely unaware of how their brain is general cognitive abilities such as attention managing these tasks, yet the answers to monitoring, inferencing, and memory questions like these provide crucial clues retrieval are used in order to organise about the nature of the cognitive architecture this information into a single meaningful for language processing. representation. A major part of language comprehension For the most part, we take the ability to is integrating new information with what is accomplish this task for granted. However, already known. Thus, Dr Van Dyke’s work for those with language-based disabilities focuses especially on memory processes. – including developmental disabilities Her research is driven by two hypotheses: (such as dyslexia, specific comprehension the first concerns the potential contribution impairment, or speech deficits) and acquired of poor memory retrieval to reading disabilities (such as language impairment disability, through failure to integrate the after brain injury) – assembling all this right information at the right time during information accurately is a major challenge. comprehension; the second concerns While clinicians and educators are on the the role that interference from similar frontlines in helping individuals to overcome representations of words (or phrases or these challenges, scientists in the field of clauses) plays in inefficient memory retrieval. psycholinguistics are conducting the basic For example, in collaboration with Dr Brian research that investigates: how the brain McElree (New York University, USA), she processes spoken and written language; showed that when a reader’s attention is what brain functions go awry in the case directed towards a group of ‘fixable things’ of language disability; and how to most (e.g. table, sink, truck), he or she has a more effectively remediate deficits when they difficult time processing the verb ‘fixed’ occur. in a sentence like, ‘It was the boat that the guy who lived by the sea fixed in two days’. Dr Julie A Van Dyke and her team at This is because readers have a harder time Haskins Laboratories are working to focusing on fixing ‘the boat’ (the correct develop a computationally precise model, interpretation) because they become referred to as a cognitive architecture, of distracted by the other ‘fixable’ things the mechanisms that support language that are also prominent in their memory. comprehension. This work requires This type of interference occurs when Understanding the methods that reveal information both about retrieval cues become associated with other the real-time processes associated with similar items in memory. In this example, comprehension, and about how the products association was along semantic lines (‘tables’, of comprehension are later accessed ‘sinks’, ‘trucks’, and ‘boats’ are all ‘fixable’). mechanisms of language and retrieved for subsequent use. This is However, interference can also arise along necessary to address questions such as: Are phonological lines (for example, words that comprehension all words, or word meanings, equally likely rhyme: ‘hat’ > ‘mat’, ‘sat’) or lexical lines HASKINS LABORATORIES Haskins Laboratories is a private, not-for-profit research institute founded in 1935, with a scientific mission to investigate the biological basis of speech, language and reading, and their related disabilities. Together with long-standing collaborators from University of Connecticut, Yale Dr Julie A Van Dyke, a senior research scientist in the field of University, and over 40 international partners, Haskins has pioneered the scientific theories that psycholinguistics at Haskins Laboratories, Connecticut, USA, is helping to guide current clinical and educational remediations for speech and reading disabilities. The over- arching mission of the Laboratories is to leverage unravel the mechanisms underlying language comprehension, including cutting-edge science to enable those with language the processes that lead to poor understanding when reading or listening. impairments to participate more fully in society.

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Figure 1 Poor readers (panels C, D) display different eye- movement patterns to good readers (Panels A, B), particularly in sentences with How close is your research to facilitating recognised, comprehension will be poor. This means that a person’s innate memory interference (Panel A in Figure 3) versus increased syntactic processing demands the development of remediation The remediation in this case should be ability need not constrain their language (or retrieval interference (Panel B in Figure 3). (panels B, D). strategies that can help poor readers at the word level, focused on improving reading) comprehension. According to our improve their comprehension skills? decoding ability. In contrast, since our focus theory, comprehension ability is determined In your research you refer to the idea While the scientific basis in support of is specifically on comprehension processes, by whether information can be retrieved of a ‘cognitive architecture’. Could you word reading remediations is extensive, we are more interested in those who have efficiently when it is needed. To achieve this, explain this term? research on effective methods for normal word decoding ability but still struggle two major components must be in place: The use of the term ‘architecture’ is a very teaching comprehension is weak and to comprehend. This is an extremely common individuals must have high quality linguistic deliberate choice. Physical architectures inconsistent. This is partly due to the occurrence, and for this reason much of representations and they must have the create human thoroughfares by specifying complexity of the comprehension task. A our research does not target individuals ability to resist interference from distracting how structures are supported and defining much greater hindrance, however, is the with diagnosed disabilities. However, at the information. These two components lead how spaces are separated. Similarly, lack of detailed process models of how extreme end of this spectrum are those who directly to specific interventions that can more a cognitive architecture specifies a comprehension takes place. For example, have perfectly normal decoding abilities but efficiently target the causes of comprehension thoroughfare for information. Just as a one of the most influential models of who have reading comprehension abilities difficulty. wall will separate people, with doorways reading comprehension – known as ‘The that are at least two standard deviations to control how they interact, so too will a Simple View of Reading’ (Gough & Tunmer, below the level expected for their age. Is there conclusive evidence for cognitive architecture separate types of 1986) – suggests that once a student These individuals have been referred to as interference in encoding and, if so, how information, and include constraints on learns to decode words, then reading ‘Specifically Poor Comprehenders’ (SPC) does it affect language comprehension? how and when information interacts. Thus, comprehension follows automatically and they have a prevalence similar to that Language is apprehended phonologically when we speak of a cognitive architecture from their oral language comprehension of dyslexia (roughly 10% of the general – even written text is transformed into we are referring to a particular processing ability. Yet it is exceedingly common for a population). When our goal is to focus on ‘silent speech’ as we read. This means that model that incorporates hypotheses child with perfectly normal oral language a specific clinical population, this is our phonological features play a fundamental about the mechanisms that support the abilities to exhibit difficulty comprehending group of interest. Recent work with Dr role during encoding: if an individual structure (e.g., memory storage and written material. In order to provide Nicole Landi (University of Connecticut) cannot perceive important phonological retrieval, attentional control), what types effective remediations for such children, suggests that SPC do not notice when they distinctions, those distinctions will not be part of information enters into the structure it is crucial to have a clear understanding retrieve incorrect information, and hence of the individual’s memory representation. (e.g., lexical, grammatical, semantic, of how the processes of comprehending cannot correct themselves. In contrast, For comprehension, however, a word’s pragmatic) and when, and how these written texts differ from comprehending skilled comprehenders realise when they’ve phonological form serves mainly as a components work together, both in normal oral language. This is one of the primary experienced retrieval interference and do ‘handle’ that allows access to its meaning. and impaired processing. For example, in goals of my research. Methods that track correct themselves. This meaning, together with the word’s our model a crucial architectural question comprehension processes as they unfold grammatical context, is what matters most is about how different types of retrieval in real time, together with targeted What are the main implications of in comprehension. We examined this idea cues are weighted during retrieval. If a experimental manipulations enable us to adopting a retrieval–interference in a study led by Dave Kush (Norwegian distractor matches the retrieval cues on identify which types of linguistic knowledge approach in the study of comprehension University of Science and Technology), in their semantic dimension, but not on their and/or general cognitive abilities (such as difficulties? which we asked whether interference from syntactic dimension, will it be retrieved? Or retrieving information from memory) matter Our research represents a major paradigm phonologically similar items held in memory more narrowly, which of several different Figure 3 most when reading specific types of texts shift in the field of reading and language (i.e., coat, wrote, note) would affect how syntactic cues matters more in a given Both encoding and retrieval interfer- (i.e., narratives, expositions, discourses, comprehension. Traditionally, the primary participants read ‘It was the boat that the context? These questions are akin to ence invoked increased activation in dorsal-lateral pre-frontal cortex, which etc.). Data of this sort can be directly explanation for poor comprehension was guy who drank coffee sailed in two days’. asking whether the door between active has been associated with conflict translated into classroom practices that can low working memory capacity, with an We found definite effects of interference memory and passive memory is like a control. However, retrieval interference improve how children are taught to read. associated assumption that a person’s from the distracting words at the point of sliding door, through which anything could was uniquely associated with posterior activations, which have been related to working memory capacity was an innate reading ‘boat’. However, these differences pass, or whether it is more like a revolving the integration of syntactic structures. How similar are the reading disabilities and immutable trait. From this perspective, had no bearing on how well participants door, which imposes a particular order on that you focus on to the more well- remediations are only weakly motivated, comprehended the sentence. What seems to the entities that pass through it. Highly known reading disabilities such as since the core-deficit is viewed as part matter more is whether readers can perceive articulated models of this sort play a crucial dyslexia? of an individual’s genetic makeup. The distinctions along semantic or syntactic role in language research, and especially in Figure 2 Dyslexia is a disability at the word reading breakthrough associated with the cue-based dimensions, and this is entirely dependent disability research, because they capture Event-related brain activity in good level, and is present in roughly 10% of the retrieval approach is the understanding that on the quality of their semantic and syntactic the underlying regularities in how the brain and poor readers while reading short passages. Good readers are better at general population. Obviously, dyslexia the mechanisms of language processing encodings. Interestingly, data from a recent manages information, and reveal ‘pressure realising when additional information can produce poor comprehension; when (including reading comprehension) require fMRI study show a qualitatively different points’ in the system where breakdowns must be retrieved (increased P300), individual words cannot be efficiently only the most minimal memory capacity. pattern of brain activation for encoding may occur. and at integrating that information into a coherent meaning representation (increased P600).

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(words that have an associated meaning: ‘hat’ > ‘hair’, ‘wig’). Dr Van Dyke has Detail suggested that retrieval interference such as this is pervasive in language processing, RESEARCH OBJECTIVES and is one of the main factors affecting Dr Van Dyke explores the cognitive comprehension ability. architecture that supports online reading and language comprehension GATHERING THE DATA processes, with a special focus on Dr Van Dyke and her team employ a range memory retrieval as a key component of of experimental methods in their research. skilled and disabled language use. The real-time behavioural measurement techniques they use include: eye-tracking FUNDING technology to study people’s eye National Institute of Child Health and movements while they are reading (see Human Development Figure 1); speed–accuracy tradeoff (SAT), which tracks changes in response accuracy COLLABORATORS with the accumulation of information over • Morgan L Bontrager (Haskins) time; and electroencephalography (EEG), • Andrew A Jahn (Haskins) which records the electrical activity of the • Clinton L Johns (Haskins) brain as it processes information (see Figure • Victor Kuperman (McMaster) 2). These techniques allow the language • Dave Kush (Norwegian University of processing architecture of the brain to Science and Technology) be characterised with precision, and are • Kazunaga Matsuki (McMaster) complemented by magnetic resonance • Ashley G Lewis (Haskins) imaging (MRI), which allows the team to • Nicole Landi (University of characterise the neurobiological foundations Connecticut and Haskins) of skilled and disabled reading. BIO Dr Van Dyke’s research is also rare in its information. Rather, there is a memory FINDING EFFECTIVE REMEDIATIONS Dr Julie A Van Dyke is a Senior Research effort to create an individualised skill profile Dr Van Dyke and colleagues have shown mechanism that encodes and stores It may seem logical to assume that poor Scientist at Haskins Laboratories, for all study participants. To accomplish partially processed information, which is readers do not possess the cue-based and holds adjunct Professorships at this, her team administers a broad range that both poor and skilled readers alike later retrieved and patched together into a retrieval system used by skilled McMaster University and the City of cognitive assessments which provides (hopefully) coherent understanding. readers, perhaps instead relying University of New York Graduate information on language-related abilities employ efficient, direct-access retrieval on inefficient, exhaustive searches Center. She earned her PhD in such as phonological processing, word during listening comprehension With her colleagues, Dr Van Dyke has of the contents of memory. Cognitive Psychology from the decoding, knowledge of syntax, vocabulary, demonstrated that a direct-access However, with Dr Clinton Johns University of Pittsburgh, a MSc and reading experience, as well as on more information retrieval mechanism that (Haskins Laboratories), Dr Van in Computational Linguistics general cognitive capacities such as IQ, best matched to particular subgroups of as here: ‘the dog, which had barked at the operates based on retrieval cues is Dyke has shown that both poor from Carnegie Mellon University, processing speed, and visual memory. readers. cat in the neighbour’s yard all morning, the key to skilled adult reading. Such a and skilled readers alike employ and BA in Computer Science from A particular emphasis in her project is to waited by the door’. Understanding this mechanism can compensate for limited efficient, direct-access retrieval during the University of Delaware. When not in include data from individuals who are not MANAGING INFORMATION sentence puts more emphasis on a person’s memory capacity, explain individual listening comprehension. This means the lab, Julie enjoys spending time with high-school graduates and who do not (and A functional cognitive architecture ability to organise information in memory variation in language comprehension, that poor readers possess the same basic her husband and four daughters. Her may not plan to) pursue higher education. supporting language comprehension must and to make appropriate connections: in and account for specific difficulty language-processing architecture as research is inspired by mothering a child This group has been largely overlooked in accommodate the fact that linguistic input – this case, to realise that it is the dog that encountered in understanding certain skilled readers. Potential remediations with spoken language impairment and previous language research, but is essential words, phrases, sentences, texts – contains waited, and not someone or something else complex grammatical constructions. In should therefore focus on reducing poor dyslexia. for providing a representative sample of many different kinds of information, that can ‘wait’, such as the cat. To do this, principle, retrieval cues can be virtually readers’ sensitivity to interference from reading ability in the general population. but can only be processed serially (e.g., a comprehender must accurately encode anything, such as a smell, a sound, a colour distracting information. Dr Van Dyke’s CONTACT Because the scale of such datasets is large – in a word-by-word fashion). This is the the grammatical relations in the sentence, or a place, that acts as a guide to what work points to the importance of using Dr Julie A Van Dyke they are more comprehensive than is typical essential challenge for the language and use these grammatical cues to select a person is supposed to remember. In instructional techniques that encourage Haskins Laboratories in psycholinguistic research – Dr Van Dyke comprehension system: to reconcile the the appropriate animate noun for the verb the case of written or spoken language learners to draw distinctions between word 300 George Street, Suite 900 and her colleagues have pioneered the use hard constraint of the serial experience of ‘waited’. comprehension, it is a person’s encoding of meanings and grammatical functions, as New Haven, CT 06511 of innovative analysis techniques. With Dr linguistic information, with the simultaneous the linguistic dimensions (e.g., phonology, well as direct their attention to appropriate Kazunaga Matsuki and Dr Victor Kuperman processing and comprehension of its Figuring out how these processes occur grammar, meaning) that matters most. linguistic cues when processing a sentence. E: [email protected] (McMaster University, Canada), Dr Van Dyke multi-dimensional features. In some cases, is important because the human ability People who have comprehension Beyond helping children and adults learn T: +1 203-865-6163 x 214 has demonstrated that a machine-learning this is not so challenging. For example, to manage and process several separate difficulties tend to have low-quality word to read, this research may also provide W: http://www.haskinslabs.org/research/ technique known as Random Forests can understanding a phrase like, ‘the dog pieces of information concurrently is representations stored in memory. These a new perspective for understanding research-areas/haskins-complab determine which assessments are most waited by the door’ is straightforward, limited: some studies suggest we can poor representations can lead to confusions acquired language deficits (e.g., due to important for explaining variation in her because each word can be easily integrated only hold between one and four items of among similarly encoded items, and stroke or brain injury), including potentially /drjvandyke experimental measures. The outcome of with what came before it. However, in many information in memory at a time. Therefore, poor comprehenders can have difficulty identifying networks of brain regions /HaskinsCompLab these studies can provide critical guidance cases, words that must be understood a complex sentence cannot be understood retrieving the correct representations when associated with managing different types of @HaskinsCompLab about which instructional techniques are together are separated from each other, in its entirety as one block piece of they need them. interference (see Figure 3).

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