Sensitivity to Word Order Cues by Normal and Language/Learning Disabled Adults

Plante, E., Gómez, R., & Gerken, L. A. (2002). Sensitivity to word order cues by normal and language/learning disabled adults. Journal of Communication Disorders, 35, 453–462.

The ability to recognize statistical regularities in inputs is considered to be an important learning mechanism emerging early in life and supporting language acquisition (Gómez & Gerken, 1999). Children with specific language impairment (SLI) on the other hand, have been found to have difficulty extracting statistical regularities from the input (Bishop, 1982).

 

In this article, Plante, Gómez, and Gerken (2002) examined statistical learning of sequential word order strings generated by an artificial grammar. Participants included 32 adults with and without personal or familial history of language/learning disabilities (L/LD). In the artificial grammar task, adults listened to novel consonant-vowel-consonant (CVC) words, with grammatical rules regarding syllable sequences for five minutes. After listening to the language, participants were asked to judge whether a new sentence spoken in the novel language obeys or violates the rules of the language.  After only five minutes of exposure to the training set, typically developing adults were able to exceed chance performance, whereas adults with L/LD showed significantly lower performance compared to the control group.

These results suggest that adults with L/LD may have difficulty in recognizing word order compared to typically developing adults. It may be adults with L/LD have more difficulty extracting the regularities available in linguistic input. Another study reviewed in this blog by Evans et al. (2009)  suggested that children with language impairment requirement more repetitions to learn the statistical patterns available in the input.

Blogger: Areej Balilah

What Causes Specific Language Impairment in Children?

Bishop, D.V. (2006). What causes specific language impairment in children? Current Directions in Psychological Science, 15 (5), 217-221.

This week’s article is an update of Bishop’s "The underlying nature of specific language impairment" discussed in the last posting looking at the more broad hypotheses of genetic vs. multiple underlying defictis as explanations for SLI.

            Studies showing that SLI runs in families suggest a genetic influence; however these results can be confounded by the fact that families share environments. Twin studies have been used to test this idea and have shown that monozygotic twins have more similar SLI profiles than dizygotic twins. Nevertheless, SLI does not follow a simple inheritance pattern suggesting that there is no ‘gene for language’. Rather, SLI may be described as a complex genetic disorder, that is, a disorder of several genes interacting with environmental factors. Indeed, Bishop’s own twin studies have provided evidence of separable genetic influences on a phonological short-term memory task (non-word repetition), and a grammatical task (adding inflectional ending to verbs), but not on an auditory perception task.  

            Overall, children with multiple deficits were more likely to be identified as SLI. Multiple routes to language acquisition may provide a protective factor such that redundancies and compensations occur in the system even if a single weakness or deficit exists. Multiple deficits, however, would impair language learning and may result in identification as SLI.

Future directions will continue to examine the development of language abilities over time, and investigate genetic and environmental interactions. 

Blogger: Lauren Perduk is currently completing her Masters of Clinical Science in Speech Language Pathology. She often participants in lab meetings with the Language and Working Memory lab. 

The Underlying Nature of Specific Language Impairment

Bishop, D. V. (1992). The underlying nature of specific language impairment. The Journal of Child Psychology and Psychiatry and Allied Disciplines, 33, 3–66.

In this classic paper entitled "The underlying nature of specific language impairment", Bishop reviews and evaluates six theories that describe SLI in terms of a core deficit in cognitive processing. The aim of this posting is to provide a brief summary of each hypothesis discussed in in this 1992 article.

Hypothesis 1 – Language Impairment as an Output Disorder

According to a view of SLI as an output disorder, the deficit lies in the ability to transform a concept in the mind to speech for output. The idea is that articulatory errors occur with such frequency in these children that this output eventually impairs the lexical route on which the concept based. However, many children with SLI do not have a significant articulatory disorder. As a result, this hypothesis cannot account for SLI.

Hypothesis 2 – Language Impairment as an Auditory Disorder

In a series of studies, Tallal and her colleagues provided evidence for auditory deficits in children with SLI. These children tended to have problems in the perception and production of rapid sequences of stimuli (Tallal & Piercy, 1973a,b).  Several examples of how the auditory perceptual impairment theory can account for several deficits seen in children with SLI are provided including phonological problems (e,g., Tallal, & Piercy, 1974), comprehension difficulties (e.g., Frumkin & Rapin, 1980), and expressive grammatical problems (Leonard et al., 1987). According to Bishop (1992), further work is necessary to fully understanding how the auditory limitations theory can account for different linguistic and non-verbal deficits seen in children with SLI.

Hypothesis 3 – Linguistic Interpretations of SLI

The third hypothesis reviewed by Bishop (1992), addresses the possibility that children with SLI are born with a deficit in an “innate language acquisition device” that has been proposed to be responsible for mastering the grammatical relations of a language. There are many ways in which this language acquisition device may cause the characteristic impairments that are observed in SLI.  One possibility is that children with SLI are born with the inability to extract the hierarchical structure of their nature language (Cromer, 1978). Although hierarchical processing deficits have been reported in children with SLI, the same pattern of performance has also been observed in other populations such as children who are deaf (Bishop, 1982), providing contradictory evidence against this theory. An alternative theory is that children with SLI are impaired in their ability to link grammatical structure to meaning (Pinker, 1989). This theory has been applied to children with SLI and their language matched peers, with the finding that children with SLI have a deficit in what appears to be an innate ability to link grammar to meaning, while typically developing children do not show the same pattern of results (Van der Lely, 1990). Although plausible, this finding does not exclude the possibility that auditory perception issues could be the core deficit in SLI.  Bishops concludes his review by stating that the current findings are not well understood and that more sophisticated analyses will need to be conducted before fully rejecting or accepting this theory.

Hypothesis 4 - Explanation of SLI in Terms of Piagetian Theory

Bishops fourth hypothesis explains SLI as being caused by a conceptual deficit. The conceptual deficit is linked to Piaget’s theory of cognitive development: He saw the ability to represent something symbolically (e.g.: using a symbol as a stand-in for an object) as being important for language. Language itself is inherently symbolic, as we are using words to represent our thoughts, actions, beliefs, etc. Some researchers have hypothesized that children with SLI are impaired in their representation of concepts, but the research findings on this are mixed. Some of the tasks used to assess conceptual development in children require verbal skills to complete, so children with SLI naturally do poorly on these. Also, children with SLI seem to do as well as their typically developing peers, it just takes them longer to do the tasks possibly implicating a speed of processing deficit and not a conceptual deficit. Overall, it appears that conceptual development is not impaired in children with SLI, and that their impairment is due to other factors.

Hypothesis 5- Learning Strategies in SLI

In the fifth theory discussed in this paper, Bishop posits that the underlying problem in SLI is a deficit in the rule-learning process. Specifically, children with SLI may have difficulty testing hypotheses about grammar, a process that is thought to be necessary in learning language. Research has been carried out to test how well children with SLI implicitly learn rules in different kinds of tasks, but results vary depending on the difficulty of the tasks. In some cases, children with SLI learn the rules as well as typically developing peers, but have less success in others. Bishop concludes that children with SLI seem to struggle with rule learning mainly when they are required to retain the rules for a time.

Hypothesis 6- Limited Information Processing Capacity as an Explanation for SLI

A limited information processing capacity model has been proposed as an explanation for SLI, where children with SLI have been thought to have a reduced capacity for verbal processing of information. This model has since been altered to account for a limited information processing system that is not restricted to verbal processing but also accounts for SLI deficits reported for some visuospatial and non-verbal information processing tasks as well. One problem with a limited information processing capacity account of SLI is that the theory is so general that it can explain almost any pattern of results in terms of capacity of limitations. Nevertheless, processing capacity in children with SLI remains an area of continued research interest.

Bloggers for hypotheses 1 through 6, respectively: Alberto Filgueirass, Areej Balilah, Alexandra Smith,  Nicolette Noonan, Laura Pauls, & Monica DaSilva 

Putting Struggling Readers on the PHAST Track

Lovett, M.W., Lacerenza, L., & Borden, S.L. (2000). Putting struggling readers on the PHAST track: A program to integrate phonological and strategy-based remedial reading instruction and maximize outcomes. Journal of Learning Disabilities, 33, 458-476.

Children with reading disabilities are frequently found to have phonological processing deficits. Phonological awareness, the ability to isolate and manipulate sounds in the language is particularly problematic for children with reading disabilities. Interventions addressing phonological awareness have been found to be effective.

In this article, the authors review a program of research leading to the development and testing of the PHAST (Phonological and Strategy Training) remedial reading program. The PHAST represents a merging of programs based on phonological analysis and blending, and word identification strategies. Early research by this group indicated that teaching all of the relevant strategies from these programs was more effective then only some, that different skills improved based on the different strategies taught, and that a combined rather than strictly sequential approach to the teaching of these strategies was most effective. The authors then go on to describe their PHAST program, which was designed to implement these best practices in reading remediation incorporating teaching of both specific and metacognitive skills for improving word reading.

Blogger: Lisa Archibald

The Impact of Dual Tasking on Sentence Comprehension in Children with Specific Language Impairment

Leclercq, A. L., Majerus, S., Prigent, G, & Maillart, C. Journal of Speech, Language, and Hearing Research, 56, 265-280.

It has been thought that children with specific language impairment (SLI) have poor attention, which may sometimes be the cause of their poor performance on language tasks. In this study, the authors argue that comprehending sentences may be especially taxing on one’s mental resources for attention. Comprehending a sentence involves engaging in multiple processes including: Processing the words as you hear them, accessing long-term memory for word meaning, and maintaining and updating the products of the sentence while still interpreting and incorporating incoming information. In order to manipulate this complex set of information, the child needs to have sufficient attention.

In the present study, the authors used a dual-task paradigm to asses how attention was related to sentence processing capacities in children with SLI and typically develop children. The sentence comprehension task was the primary task, and an interfering non-verbal task, presumed to tax one’s attentional resources, was the secondary task. Performance of children with SLI was compared to age-matched and grammar-matched control groups. It was hypothesized that while engaging in the attentionally-demanding secondary task, the performance of the children with SLI on the primary sentence recall task would be especially impaired because of a resource-sharing trade-off.

The results of this study revealed that children with SLI have poor attentional capacity. For children with SLI and their grammatical controls, performance on the sentence comprehension task was impaired when they were also engaged in the secondary non-verbal task. However, these results do not support the hypothesis that poor attentional abilities are a core deficit in SLI. Rather, because children with SLI and younger, grammar matched controls demonstrated similar levels of performance on the dual task, it was suggested that SLI is characterized by a slowed development of attentional and language domains, rather than an attention deficit.

These findings suggest that the development of attention in children with SLI may lag behind their peers, and this does have implications for their language abilities.

Blogger: Nicolette Noonan is a Master’s student in the Speech and Language Sciences program.

Assessment and Treatment of Working Memory Deficits in School-Age Children: The Role of the Speech-Language Pathologist

Boudreau, D., & Costanza-Smith, A. (2011). Assessment and treatment of working memory deficits in school-age children: The role of the speech-language pathologist. Language, Speech, and Hearing Sciences in Schools, 42, 152-166.

This article provides a clinically useful summary of working memory theory, relationship to language and language impairment, and assessment and intervention issues.

Working memory refers to the temporary storage and processing of information. Working memory is considered to have both domain-specific short-term storage (memory) systems for holding information in mind, and a domain-general central executive responsible for controlling attention and allocating resources (Baddeley & Hitch, 1974). The short-term memory system responsible for holding phonological information in mind, phonological short-term memory, is thought to play an important role in the learning of new word forms (Gathercole, 2006). Working memory for phonological/verbal information taps both phonological short-term memory and the central executive, and is referred to as functional working memory by Boudreau and Costanza-Smith. Functional working memory has been found to be related to more complex skills such as language comprehension and academic achievement. As well, poor phonological short-term memory and functional working memory have been implicated in language impairment given evidence that children with language impairment do poorly on such tasks.

Clinicians may find information about a child’s phonological short-term memory and functional memory are in psychoeducational assessment reports. In addition, standardized tests of phonological processing and language sometimes include tasks that tap these processes. Evidence regarding working memory intervention is reviewed along with classroom strategies that may facilitate learning in children with weak working memory.

Blogger: Lisa Archibald

In Two Minds: Dual-Process Accounts of Reasoning

Evans, J.S. (2003). In two minds: dual-process accounts of reasoning. TRENDS in Cognitive Sciences, Volume 7 (10), 454-459.

Sometimes we take action before we’ve even realized we’re thinking about it. We hold our hand out to catch a ball; we produce a well-formed sentence. At other times, we use our brains to work out a problem like the answer to a difficult math equation, or to form an opinion on a particular issue. In this review paper, Evans (2003) describes these two distinct forms of reasoning, and argues that they are supported by separate cognitive systems in the brain.

System 1 is sometimes called our implicit reasoning, or unconscious system. It is thought to be the universal cognition that is shared between humans and other animals. Even though the brain goes through many steps using this type of reasoning, we’re usually only aware of the end product (in Evan’s terms, ‘only the final product is posted to consciousness’). System 1 processes are based on associative learning that activates specific neural networks. As a result, System 1 knowledge is based on prior experiences and beliefs. When we experience a flame and the sensation of heat together repeatedly, we begin to associate fire with heat and pull away from fire even without thinking about it. Evan’s argues that the learning mechanisms of this system are domain-general, but that the function is domain-specific.

System 2 is thought to have evolved more recently and to be unique to humans. Its processes are slower, operate in sequence, and are under voluntary control. This system requires the use of working memory (WM) and is therefore restricted to the limitations of WM (e.g., how much you can hold in mind at one time). The purpose of System 2 is for abstract, hypothetical thinking. Consider the example of how I decided to get to campus today: System 1 instinctively reaches for the car keys as this is how I have travelled to campus all winter long; however, System 2 constructs a mental model of possibilities, such as taking into account it is now Spring, the temperature is warmer, and the roads are clear, therefore I could dust of my bicycle and get some exercise while I travel to school, which has health benefits compared to sitting in a car driving. System 2 would also take into consideration the fact that my bicycle will require a tune up in order to use it and I unfortunately do not have enough time to do the work if I am to arrive on time, therefore I should drive to campus today in my car and make some time on the weekend to get my bicycle ready. It is clear from this example that the two processes interact with one another depending on what is being reasoned.

One technique used to investigate these two systems is a deductive reasoning paradigm. The participant judges whether an argument is true or false requiring reasoning using System 2. Sometimes the argument uses familiar information in a believable or unbelievable way. Judgments influenced by this prior knowledge reflect the influence of System 1.  Neuropsychological studies employing functional magnetic resonance imaging (fMRI) provides additional evidence for the distinction between System 1 and 2 processes because separate brain areas are activated on tasks tapping System 1 and/or 2.

Of interest to our lab is how these systems might influence language learning.

Blogger: Ian Gallant is about to graduate from the Masters of Clinical Science degree in Speech Language Pathology. He hangs out in the LWM lab on a regular basis. 

Morpheme Learning of Children With Specific Language Impairment Under Controlled Instructional Conditions

Connell, P. & Stone, C. (1992). Morpheme learning of children with specific language impairment under controlled instructional conditions. Journal of Speech and Hearing Research, Volume 35, 844-852.

Connell and Stone (1992) examined how children with Specific Language Impairment (SLI) learn differently than Typically Developing (TD) children. The study investigated language learning in children with SLI under controlled experimental teaching conditions. According to Connell’s previous work (1986), children with SLI do not differ from children with TD in learning language rules during teaching sessions under an imitation condition that requires imitating and producing language rules. In comparison, children with SLI showed poorer learning of language rules under a modeling condition that required only listening to the input.    

The 1992 study compared the comprehension and production performance of children with SLI, and either age or language - matched groups. Specifically, it examined children’s mastery of learning the new morphemes under modeling and imitation instruction conditions. Using a computerized language- teaching program, children were taught a set of invented morphemes over a two-week period. The results indicated that for morpheme comprehension, there was no difference between children with SLI and the control groups under modeling or imitation conditions. On the other hand, for morpheme production, children with SLI scored significantly lower than the other groups in the modeling, but not the imitation condition. In sum, children with SLI produced the invented new morphemes more reliably under imitation trials than modeling trials. However, TD children showed no such preferences regarding either the molding or imitation instruction.

These results suggest that children with SLI may fail to learn language simply from hearing language models. Rather, children with SLI may benefit from learning in a richer context involving production and comprehension.

Blogger: Areej Balilah

Learning Non-Adjacent Regularities at Age 0;7

Gervain, J., & Werker, J.F. (In press). Learning non-adjacent regularities at age 0;7. Journal of Child Language, DOI:10.1017/S0305000912000256

The ability to learn rules is an important part of language learning. Infants have been found to be able to learn certain regularities involving both adjacent repetitions (e.g., ‘wo fe fe’) and non-adjacent repetitions (e.g., ‘wo fe wo’). This study compared learning of adjacent and non-adjacent repetitions in 7-month old infants to examine evidence that these patterns are processed differently in the brain.

In each of two experiments, infants completed a test phase: the infant heard a ‘word’ that either followed a pattern (e.g., adjacent repetition) or had no pattern (e.g., ‘wo fe  ga’) at the same time they looked to a light. If the infant noticed, or was familiar with, the pattern of the word being played, the infant would look away quickly. If the word being played was novel, the infant would look longer. A ‘looking time difference’ would show that the infant discriminated the pattern from the novel words. In Experiment 1, there was a familiarization phase: the infants heard words that followed the pattern (e.g., adjacent repetition) for 2 minutes prior to the test phase. In Experiment 2, the infant completed the test phase only with no familiarization phase.

Infants showed a ‘looking time difference’ for both adjacent and non-adjacent repetitions in Experiment 1 with the familiarization phase, but not Experiment 2. There were no differences in learning across trials for adjacent or non-adjacent repetitions.  These results indicate that the infants learned the relevant rule during the familiarization phase in Experiment 1. There was no evidence of a different learning mechanism for adjacent vs. non-adjacent repetitions, though more research at other stages of development is needed.

The findings provide further evidence of the importance of pattern learning in language acquisition. Children with language impairment may need more explicit (‘meta’) strategies to notice/learn linguistics patterns/rules.

Blogger: Lisa Archibald