Processing Verb Meanings and the Declarative/Procedural Model: A Developmental Study

According to the Declarative/Procedural Model, the lexicon depends on declarative memory while grammar relies on procedural memory. Furthermore, procedural memory underlies the sequential processing of language. Thus, this system is important for predicting the next item in a sentence. Verb processing represents a good candidate to test this assumption. Semantic representations of verbs include information about the protagonists in the situations they refer to. This semantic knowledge is acquired implicitly and used during verb processing, such that the processing of a verb preactivates its typical patients (e.g., the window for break). Thus, determining how the patient typicality effect appears during children’s cognitive development could provide evidence about the memory system that is dedicated to this effect. Two studies are presented in which French children aged 6–10 and adults made grammaticality judgments on 80 auditorily presented sentences. In Experiment 1, the verb was followed by a typical patient or by a less typical patient. In Experiment 2, grammatical sentences were constructed such that the verb was followed either by a typical patient or by a noun that could not be a patient of that verb. The typicality effect occurs in younger children and is interpreted in terms of developmental invariance. We suggest that this effect may depend on procedural memory, in line with studies that showed that meaning is necessary to allow procedural memory to learn the sequence of words in a sentence.

Efficiency of lexical access in children with autism spectrum disorders: does modality matter?

The provision of visual support to individuals with an autism spectrum disorder (ASD) is widely recommended. We explored one mechanism underlying the use of visual supports: efficiency of language processing. Two groups of children, one with and one without an ASD, participated. The groups had comparable oral and written language skills and nonverbal cognitive abilities. In two semantic priming experiments, prime modality and prime-target relatedness were manipulated. Response time and accuracy of lexical decisions on the spoken word targets were measured. In the first uni-modal experiment, both groups demonstrated significant priming effects. In the second experiment which was cross-modal, no effect for relatedness or group was found. This result is considered in the light of the attentional capacity required for access to the lexicon via written stimuli within the developing semantic system. These preliminary findings are also considered with respect to the use of visual support for children with ASD.

Auditory implicit semantic priming in Spanish-speaking children with and without specific language impairment

We analyzed whether Spanish-speaking children with Specific Language Impairment (SLI) showed deficits in lexical-semantic processing/organization, and whether these lexical measures correlated with standardized measures of language abilities. Fourteen children with Typical Language Development (TLD) and 16 age-matched children with SLI (8;0-9;11 years) participated. In a Lexical Decision (LD) task with implicit semantic priming, children judged whether a given speech pair contained two words (semantically related/unrelated) or a word-pseudoword. Children received a comprehensive language and reading test battery. Children with TLD exhibited significant semantic priming; they were faster for semantically related word pairs than for unrelated (p < .001) and than for word-pseudoword pairs (p < .0002). The group with SLI did not exhibit significant semantic priming, despite showing more variability. Children with SLI made significantly slower LDs [F(1, 26) = 4.61, p < .05, partial η2 = .15] and more errors [F(1, 26) = 4.16, p < .05, partial η2 = .13] than children with TLD. Mean response time across all LD conditions and the receptive vocabulary (PPVT-III) were significantly negativity correlated for children with SLI (r = -.71, p = .004). Children with SLI, especially those with the poorest language scores, showed a semantic-lexical deficit and a weakness in lexical-semantic association networks. Their performance on the LD task was significantly slower and poorer than for children with TLD. Increasing a child's vocabulary may benefit lexical access.

Lexical priming in fluent and with developmental stuttering children

PURPOSE

To examine the possible relationship between lexical variables (categorization and naming) and developmental stuttering.

METHODS

Thirty Brazilian Portuguese speaking children with ages ranging from 7 to 9 years and 11 months participated in the study. We applied a lexical priming paradigm to experimentally investigate whether children with developmental stuttering (Research Group) differed from their fluent peers (Control Group), with respect to reaction time in three conditions - control (without prime); semantically related prime, and semantically independent prime - of two experimental tasks: categorization and naming of the target stimulus.

RESULTS

No difference between groups was observed in reaction time on the categorization task. However, there was a condition effect showing that, for both groups, reaction time was shorter in the semantically related prime condition when compared to the no prime condition. In the naming task, a between-group difference was observed in reaction time, indicating a longer reaction time in the Research Group than the Control Group. There was no condition effect on naming, i.e. the Research Group showed slower reaction time regardless of prime type.

CONCLUSIONS

The results confirm the hypothesis that, in children with developmental stuttering, readiness in motor programming of speech is slowed when compared to fluent children. There is no difference between groups when the lexical function does not require speech readiness.

Gray-white matter and cerebrospinal fluid volume differences in children with Specific Language Impairment and/or Reading Disability

We studied gray-white matter and cerebrospinal fluid (CSF) alterations that may be critical for language, through an optimized voxel-based morphometry evaluation in children with Specific Language Impairment (SLI), compared to Typical Language Development (TLD). Ten children with SLI (8;5-10;9) and 14 children with TLD (8;2-11;8) participated. They received a comprehensive language and reading test battery. We also analyzed a subgroup of six children with SLI+RD (Reading Disability). Brain images from 3-Tesla MRIs were analyzed with intelligence, age, gender, and total intracranial volume as covariates. Children with SLI or SLI+RD exhibited a significant lower overall gray matter volume than children with TLD. Particularly, children with SLI showed a significantly lower volume of gray matter compared to children with TLD in the right postcentral parietal gyrus (BA4), and left and right medial occipital gyri (BA19). The group with SLI also exhibited a significantly greater volume of gray matter in the right superior occipital gyrus (BA19), which may reflect a brain reorganization to compensate for their lower volumes at medial occipital gyri. Children with SLI+RD, compared to children with TLD, showed a significantly lower volume of: (a) gray matter in the right postcentral parietal gyrus; and (b) white matter in the right inferior longitudinal fasciculus (RILF), which interconnects the temporal and occipital lobes. Children with TLD exhibited a significantly lower CSF volume than children with SLI and children with SLI+RD respectively, who had somewhat smaller volumes of gray matter allowing for more CSF volume. The significant lower gray matter volume at the right postcentral parietal gyrus and greater cerebrospinal fluid volume may prove to be unique markers for SLI. We discuss the association of poor knowledge/visual representations and language input to brain development. Our comorbid study showed that a significant lower volume of white matter in the right inferior longitudinal fasciculus may be unique to children with SLI and Reading Disability. It was significantly associated to reading comprehension of sentences and receptive language composite z-score, especially receptive vocabulary and oral comprehension of stories.