Joanne Arciuli

Statistical Learning Is Related to Reading Ability in Children and Adults

There is little empirical evidence showing a direct link between a capacity for statistical learning (SL) and proficiency with natural language. Moreover, discussion of the role of SL in language acquisition has seldom focused on literacy development. Our study addressed these issues by investigating the relationship between SL and reading ability in typically developing children and healthy adults. We tested SL using visually presented stimuli within a triplet learning paradigm and examined reading ability by administering the Wide Range Achievement Test (WRAT-4; Wilkinson & Robertson, 2006). A total of 38 typically developing children (mean age of 9;5 years, range 6;4-12;5) and 37 healthy adults (mean age of 21 years, range 18-34) were assessed. In children, SL was significantly related to reading ability. Importantly, this relationship was independent of grade and also age. The adult data, too, revealed that SL was significantly related to reading ability. A regression analysis of the combined child and adult data revealed that SL accounted for a unique amount of variance in reading ability, after age and attention had been taken into consideration. For the first time, this study provides empirical evidence that a capacity for more effective SL is related to higher reading ability in the general population.

The processing of lexical stress during visual word recognition: Typicality effects and orthographic correlates

Many studies that have examined reading at the single-word level have been restricted to the processing of monosyllabic stimuli, and, as a result, lexical stress has not been widely investigated. In the experiments reported here, we used disyllabic words and nonwords to investigate the processing of lexical stress during visual word recognition. In Experiments 1 and 2, we found an effect of stress typicality in naming and lexical decision. Typically stressed words (trochaic nouns and iambic verbs) elicited fewer errors than atypically stressed words (iambic nouns and trochaic verbs). In Experiment 3, we carried out an analysis of 340 word endings and found clear orthographic correlates of both grammatical category and lexical stress in word endings. In Experiment 4, we demonstrated that readers are sensitive to these cues in their processing of nonwords during two tasks: sentence construction and stress assignment. We discuss the implications of these findings with regard to psycholinguistic models of single-word reading.

Statistical learning in typically developing children: the role of age and speed of stimulus presentation

It is possible that statistical learning (SL) plays a role in almost every mental activity. Indeed, research on SL has grown rapidly over recent decades in an effort to better understand perception and cognition. Yet, there remain gaps in our understanding of how SL operates, in particular with regard to its (im)mutability. Here, we investigated whether participant-related variables (such as age) and task-related variables (such as speed of stimulus presentation) affect visual statistical learning (VSL) in typically developing children. We tested 183 participants ranging in age from 5 to 12 years and compared three speeds of presentation (using stimulus durations of 800, 400 and 200 msecs). A multiple regression analysis revealed significant effects of both age and speed of presentation - after attention during familiarization and gender had been taken into consideration. VSL followed a developmental trajectory whereby learning increased with age. The amount of learning increased with longer presentation times (as shown by Turk-Browne, Jungé & Scholl, 2005, in their study of adults). There was no significant interaction between the two variables. These findings assist in elucidating the nature of statistical learning itself. While statistical learning can be observed in very young children and at remarkably fast presentation times, participant- and task-related variables do impact upon this type of learning. The findings reported here may serve to enhance our understanding of individual differences in the cognitive and perceptual processes that are thought to rely, at least in part, on SL (e.g. language processing and object recognition).

Stressing what is important: Orthographic cues and lexical stress assignment

Computational models of reading have typically focused on monosyllabic words. However extending those models to polysyllabic word reading can uncover critical points of distinction between competing models. We present a connectionist model of stress assignment that learned to map orthography onto stress position for English disyllabic words. We compared the performance of the connectionist model to Rastle and Colthearts [(2000).] rule-based model of stress assignment for words and nonwords. The connectionist model performed well on predicting human performance in reading nonwords that both contained and did not contain affixes, whereas the Rastle and Coltheart model performed well only on nonwords with affixes. The connectionist model provides an important first step to simulating all aspects of polysyllabic word reading, and indicates that a probabilistic approach to stress assignment can reflect human performance on stress assignment for both words and nonwords.

Individual Differences in Statistical Learning Predict Children's Comprehension of Syntax.

Variability in childrens language acquisition is likely due to a number of cognitive and social variables. The current study investigated whether individual differences in statistical learning (SL), which has been implicated in language acquisition, independently predicted 6- to 8-year-olds comprehension of syntax. Sixty-eight (N = 68) English-speaking children completed a test of comprehension of four syntactic structures, a test of SL utilizing nonlinguistic visual stimuli, and several additional control measures. The results revealed that SL independently predicted comprehension of two syntactic structures that show considerable variability in this age range: passives and object relative clauses. These data suggest that individual differences in childrens capacity for SL are associated with the acquisition of the syntax of natural languages.

Advancing our understanding of the link between statistical learning and language acquisition: The need for longitudinal data

Mastery of language can be a struggle for some children. Amongst those that succeed in achieving this feat there is variability in proficiency. Cognitive scientists remain intrigued by this variation. A now substantial body of research suggests that language acquisition is underpinned by a child’s capacity for statistical learning (SL). Moreover, a growing body of research has demonstrated that variability in SL is associated with variability in language proficiency. Yet, there is a striking lack of longitudinal data. To date, there has been no comprehensive investigation of whether a capacity for SL in young children is, in fact, associated with language proficiency in subsequent years. Here we review key studies that have led to the need for this longitudinal research. Advancing the language acquisition debate via longitudinal research has the potential to transform our understanding of typical development as well as disorders such as autism, specific language impairment, and dyslexia.

Why Word Learning is not Fast.

Upon fast mapping, children rarely retain new words even over intervals as short as 5 min. In this study, we asked whether the memory process of encoding or consolidation is the bottleneck to retention. Forty-nine children, mean age 33 months, were exposed to eight 2- or-3-syllable nonce neighbors of words in their existing lexicons. Didactic training consisted of six exposures to each word in the context of its referent, an unfamiliar toy. Productions were elicited four times: immediately following the examiner’s model, and at 1-min-, 5-min-, and multiday retention intervals. At the final two intervals, the examiner said the first syllable and provided a beat gesture highlighting target word length in syllables as a cue following any erred production. The children were highly accurate at immediate posttest. Accuracy fell sharply over the 1-min retention interval and again after an additional 5 min. Performance then stabilized such that the 5-min and multiday posttests yielded comparable performance. Given this time course, we conclude that it was not the post-encoding process of consolidation but the process of encoding itself that presented the primary bottleneck to retention. Patterns of errors and responses to cueing upon error suggested that word forms were particularly vulnerable to partial decay during the time course of encoding.

“Um, I can tell you're lying”: Linguistic markers of deception versus truth-telling in speech

Lying is a deliberate attempt to transmit messages that mislead others. Analysis of language behaviors holds great promise as an objective method of detecting deception. The current study reports on the frequency of use and acoustic nature of “um” and “like” during laboratory-elicited lying versus truth-telling. Results obtained using a within-participants false opinion paradigm showed that instances of “um” occur less frequently and are of shorter duration during lying compared to truth-telling. There were no significant differences in relation to “like.” These findings contribute to our understanding of the linguistic markers of deception behavior. They also assist in our understanding of the role of “um” in communication more generally. Our results suggest that “um” may not be accurately conceptualized as a filled pause/hesitation or speech disfluency/error whose increased usage coincides with increased cognitive load or increased arousal during lying. It may instead carry a lexical status similar to interjections and form an important part of authentic, effortless communication, which is somewhat lacking during lying.

Effects of stress typicality during spoken word recognition by native and nonnative speakers of English: evidence from onset gating.

Onset gating was used to investigate the effects of stress typicality during the processing of disyllabic nouns and verbs by 34 native and 36 nonnative speakers of English. We utilized 50-msec increments and included two conditions. In the silenced condition, only word onsets were presented (the participants had no information about the duration or stress pattern of the entire word). In the filtered condition, word onsets were presented with a low-pass filtered version of the remainder of the word (this type of filtering provides duration and stress information in the absence of phonemic information). The results demonstrated significant effects of stress typicality in both groups of speakers. Typically stressed trochaic nouns and iambic verbs exhibited advantaged processing, as compared with atypically stressed iambic nouns and trochaic verbs. There was no significant effect of presentation condition (silenced or filtered). The results are discussed in light of recent research in which the effects of lexical stress during spoken word recognition have been investigated.

Putting an "end" to the motor cortex representations of action words.

Language processing is an example of implicit learning of multiple statistical cues that provide probabilistic information regarding word structure and use. Much of the current debate about language embodiment is devoted to how action words are represented in the brain, with motor cortex activity evoked by these words assumed to selectively reflect conceptual content and/or its simulation. We investigated whether motor cortex activity evoked by manual action words (e.g., caress) might reflect sensitivity to probabilistic orthographic–phonological cues to grammatical category embedded within individual words. We first review neuroimaging data demonstrating that nonwords evoke activity much more reliably than action words along the entire motor strip, encompassing regions proposed to be action category specific. Using fMRI, we found that disyllabic words denoting manual actions evoked increased motor cortex activity compared with non-body-part-related words (e.g., canyon), activity which overlaps that evoked by observing and executing hand movements. This result is typically interpreted in support of language embodiment. Crucially, we also found that disyllabic nonwords containing endings with probabilistic cues predictive of verb status (e.g., -eve) evoked increased activity compared with nonwords with endings predictive of noun status (e.g., -age) in the identical motor area. Thus, motor cortex responses to action words cannot be assumed to selectively reflect conceptual content and/or its simulation. Our results clearly demonstrate motor cortex activity reflects implicit processing of ortho-phonological statistical regularities that help to distinguish a words grammatical class.