An Integrated Perspective on Spatio-Temporal Attention and Infant Language Acquisition.

Efficiency in the early ability to switch attention toward competing visual stimuli (spatial attention) may be linked to future ability to detect rapid acoustic changes in linguistic stimuli (temporal attention). To test this hypothesis, we compared individual performances in the same cohort of Italian-learning infants in two separate tasks: (i) an overlap task, measuring disengagement efficiency for visual stimuli at 4 months (Experiment 1), and (ii) an auditory discrimination task for trochaic syllabic sequences at 7 months (Experiment 2). Our results indicate that an infant's efficiency in processing competing information in the visual field (i.e., visuospatial attention; Exp. 1) correlates with the subsequent ability to orient temporal attention toward relevant acoustic changes in the speech signal (i.e., temporal attention; Exp. 2). These results point out the involvement of domain-general attentional processes (not specific to language or the sensorial domain) playing a pivotal role in the development of early language skills in infancy.

Attentional engagement during syllable discrimination: The role of salient prosodic cues in 6- to 8-month-old infants.

Prosodic cues drive speech segmentation and guide syllable discrimination. However, less is known about the attentional mechanisms underlying an infant's ability to benefit from prosodic cues. This study investigated how 6- to 8-month-old Italian infants allocate their attention to strong vs. weak syllables after familiarization with four repeats of a single CV sequence with alternating strong and weak syllables (different syllables on each trial). In the discrimination test-phase, either the strong or the weak syllable was replaced by a pure tone matching the suprasegmental characteristics of the segmental syllable, i.e., duration, loudness and pitch, whereas the familiarized stimulus was presented as a control. By using an eye-tracker, attention deployment (fixation times) and cognitive resource allocation (pupil dilation) were measured under conditions of high and low saliency that corresponded to the strong and weak syllabic changes, respectively. Italian learning infants were found to look longer and also to show, through pupil dilation, more attention to changes in strong syllable replacement rather than weak syllable replacement, compared to the control condition. These data offer insights into the strategies used by infants to deploy their attention towards segmental units guided by salient prosodic cues, like the stress pattern of syllables, during speech segmentation.

The effect of spatio-temporal distance between visual stimuli on information processing in children with Specific Language Impairment.

The purpose of this study is to evaluate whether children with Specific Language Impairment (SLI) have a deficit in processing a sequence of two visual stimuli (S1 and S2) presented at different inter-stimulus intervals and in different spatial locations. In particular, the core of this study is to investigate whether S1 identification is disrupted due to a retroactive interference of S2. To this aim, two experiments were planned in which children with SLI and children with typical development (TD), matched by age and non-verbal IQ, were compared (Experiment 1: SLI n=19; TD n=19; Experiment 2: SLI n=16; TD n=16). Results show group differences in the ability to identify a single stimulus surrounded by flankers (Baseline level). Moreover, children with SLI show a stronger negative interference of S2, both for temporal and spatial modulation. These results are discussed in the light of an attentional processing limitation in children with SLI.

Real-time comprehension of gender and number in four- to seven-year-old children: a study of the relationship between Italian clitic pronouns and visual picture referents.

The gender and number of a direct object clitic pronoun are based on the gender and number of the noun to which it refers. Grammatical gender is an intrinsic property of the lexical item that is independent from the natural sex of referents, whereas number is a non-intrinsic feature of nouns based on the conceptual level of quantity. The aim of this paper is to investigate children's ability in matching Italian direct object clitic pronouns to an inanimate visual referent on the basis of number or gender information. The dependent variables are accuracy and response time. A total of sixty-nine children aged from 4;6 to 7;5 participated. The results show that children are more accurate and faster in selecting the referent when they use number information compared to the condition in which this matching operation is led by gender.

Non-word repetition: the relationship between weak syllables and the omission of grammatical morphemes in children with specific language impairment.

Non-word (NW) repetition in children with specific language impairment (SLI) is a skill related to, but genetically separate from, grammatical ability. Prosodic structure of the syllables may bridge the gap between these two abilities. A NW repetition task was compared in a group of 15 preschool Italian children with SLI (ranged in age from 3;11 to 5;8) and 15 younger typically developing children (aged from 2;11 to 3;7) matched for mean length of utterance (TD-MLU). Grammatical ability was tested through a probe for direct-object clitic pronouns which is one of the most useful clinical markers in the Italian language. In NW repetition, children with SLI deleted more syllables than the TD-MLU children. The omission of weak syllables in a pre-stress position was a significant predictor of the omission of clitic pronouns. The present study shows that the link between grammar and NW is due to a prosodic characteristic that is more universally challenging in children with SLI.

Clinical markers in Italian-speaking children with and without specific language impairment: a study of non-word and real word repetition as predictors of grammatical ability.

BACKGROUND: In many languages a weakness in non-word repetition serves as a useful clinical marker of specific language impairment (SLI) in children. However, recent work in Italian has shown that the repetition of real words may also have clinical utility. For young typically developing Italian children, real word repetition is more predictive of particular grammatical abilities than is non-word repetition. This finding is important because these particular grammatical abilities--the production of present-tense third-person plural inflections and direct-object clitic pronouns--are precisely those that are problematic for Italian-speaking children with SLI. Along with their grammatical requirements, these two morpheme types present a significant phonological/prosodic challenge for these children. AIMS: To replicate the findings with young typically developing Italian children and to determine whether real word repetition is also more predictive of the use of these two morpheme types than is non-word repetition in a group of Italian-speaking children with SLI. METHODS & PROCEDURES: Seventeen Italian-speaking children with SLI and 17 younger typically developing children matched for mean length of utterance participated in tasks of real word and non-word repetition as well as tasks requiring the production of direct-object clitic pronouns and present-tense third-person plural inflections. OUTCOMES & RESULTS: Children with SLI were less accurate than their younger peers on all measures. Importantly, for the younger typically developing children, real word repetition explained a significant amount of variance in the use of third-person plural inflections and direct-object clitic pronouns. For the children with SLI, in contrast, non-word repetition was a significant predictor, whereas real word repetition was not a contributing factor. CONCLUSIONS & IMPLICATIONS: It is argued that in Italian SLI, the grammatical details showing the greatest weakness present phonological/prosodic obstacles as well as grammatical challenges to these children. Consequently, non-word repetition emerges as a predictor of these grammatical weaknesses in SLI, unlike the profile observed in typically developing Italian children.

The effects of production demands on grammatical weaknesses in specific language impairment: the case of clitic pronouns in Italian.

PURPOSE: Extended optional use of direct object clitic pronouns (e.g., la in Paula la vede ["Paula sees her"]) appears to be a clinical marker for specific language impairment (SLI) in Italian. In this study, we examined whether sentence production demands might influence the degree to which Italian-speaking children with SLI produced clitics. METHOD: Preschool-age children with SLI ( n = 15) and 2 groups of younger typically developing children ( n = 15 each) participated. Production demands were varied through use of a syntactic priming task. RESULTS: The children with SLI were more likely than the comparison children to omit the clitic in a control condition in which they had to describe a target picture without the benefit of a preceding sentence prime. The children with SLI were also more likely to describe target pictures using a default clitic or a clitic that had appeared in the preceding prime sentence but was inappropriate for the target. CONCLUSIONS: The findings suggest that children with SLI have difficulty generating a sentence containing a grammatical slot for a clitic when production demands are increased, and when they succeed in generating such a sentence, they often cannot at the same time retrieve the appropriate clitic form.

Real-word and nonword repetition in Italian-speaking children with specific language impairment: a study of diagnostic accuracy.

PURPOSE: Using 2 different scoring methods, the authors examined the diagnostic accuracy of both real-word and nonword repetition in identifying Italian-speaking children with and without specific language impairment (SLI). METHOD: A total of 34 children ages 3;11-5;8 (years;months) participated--17 children with SLI and 17 typically developing children matched for age (TD-A children). Children completed real-word and nonword repetition tasks. The capacity of real-word and nonword repetition tasks to discriminate children with SLI from TD-A was examined through binary logistic regression and receiver operating characteristic curves. RESULTS: Both real-word and nonword repetition showed good (or excellent) sensitivity and specificity in distinguishing children with SLI from their TD peers. CONCLUSIONS: Nonword repetition appears to be a useful diagnostic indicator for Italian, as in other languages. In addition, real-word repetition also holds promise. The contributions of each type of measure are discussed.

Visual attentional engagement deficits in children with specific language impairment and their role in real-time language processing.

In order to become a proficient user of language, infants must detect temporal cues embedded within the noisy acoustic spectra of ongoing speech by efficient attentional engagement. According to the neuro-constructivist approach, a multi-sensory dysfunction of attentional engagement - hampering the temporal sampling of stimuli - might be responsible for language deficits typically shown in children with Specific Language Impairment (SLI). In the present study, the efficiency of visual attentional engagement was investigated in 22 children with SLI and 22 typically developing (TD) children by measuring attentional masking (AM). AM refers to impaired identification of the first of two sequentially presented masked objects (O1 and O2) in which the O1-O2 interval was manipulated. Lexical and grammatical comprehension abilities were also tested in both groups. Children with SLI showed a sluggish engagement of temporal attention, and individual differences in AM accounted for a significant percentage of unique variance in grammatical performance. Our results suggest that an attentional engagement deficit - probably linked to a dysfunction of the right fronto-parietal attentional network - might be a contributing factor in these children's language impairments.

Putting singular and plural morphology in context*.

This study explores the development of children's knowledge of linguistic and pragmatic aspects of singular and plural in Italian, for definite articles (Experiment 1) and verbs (Experiment 2). Participants aged three to adult were asked to pick objects from two dishes, each with a different number of items on them (one vs. two), following the morphological information. Results show that children understand that singular forms refer to 'one' at about age four, whereas they understand that plural forms refer to 'more than one' when they are older than six. Moreover, children use singular and plural knowledge in appropriate relation with the referential context only when they are about six.

A cross-linguistic study of real-word and non-word repetition as predictors of grammatical competence in children with typical language development.

BACKGROUND: Although relationships among non-word repetition, real-word repetition and grammatical ability have been documented, it is important to study whether the specific nature of these relationships is tied to the characteristics of a given language. AIMS: The aim of this study is to explore the potential cross-linguistic differences (Italian and English) in the relationship among non-word repetition, real-word repetition, and grammatical ability in three-and four-year-old children with typical language development. METHODS & PROCEDURES: To reach this goal, two repetition tasks (one real-word list and one non-word list for each language) were used. In Italian the grammatical categories were the third person plural inflection and the direct-object clitic pronouns, while in English they were the third person singular present tense inflection and the past tense in regular and irregular forms. OUTCOMES & RESULTS: A cross-linguistic comparison showed that in both Italian and English, non-word repetition was a significant predictor of grammatical ability. However, performance on real-word repetition explained children's grammatical ability in Italian but not in English. CONCLUSIONS & IMPLICATIONS: Abilities underlying non-word repetition performance (e.g., the processing and/or storage of phonological material) play an important role in the development of children's grammatical abilities in both languages. Lexical ability (indexed by real-word repetition) showed a close relationship to grammatical ability in Italian but not in English. Implications of the findings are discussed in terms of cross-linguistic differences, genetic research, clinical intervention and methodological issues.

Real-word repetition as a predictor of grammatical competence in Italian children with typical language development.

BACKGROUND: Non-word repetition in children is a skill related to, but separable from grammatical ability. Lexical skill may bridge the gap between these two abilities. AIMS: The main aim was to determine whether real-word-repetition tasks could be better as predictors of grammatical ability than non-word-repetition tasks in children with typical language. This proposal was pursued because lexical knowledge was assumed to make performance in repetition tasks more representative of other language abilities, whereas non-word-repetition tasks are heavily influenced by phonological short-term memory. METHODS & PROCEDURES: In order to investigate this possibility, three repetition tasks (two real-word lists characterized by different lexical knowledge and one non-word list), were compared in three groups of three- to four-year-olds with typical language (42 children). Grammatical ability was tested through probes for third-person plural inflection and direct-object critic use. OUTCOMES & RESULTS: Real words were repeated more accurately than non-words and the non-words were more sensitive to Syllable length than real words. Performance on all repetition tasks was correlated with grammatical ability, but real words predicted variance in grammatical ability to a greater extent than non-words. CONCLUSIONS & IMPLICATIONS: Given the lexical information contained in real words, repetition of such words was a better predictor of grammatical ability than non-word repetition. Future research should replicate and extend these results. Tasks using real words may also have considerable clinical potential; for this reason, these tasks might also be included in studies of children with language impairment.