ABSTRACT
The research aims to reveal neural indicators of recognition for iconic words and the possible cross-modal multisensory integration behind this process. The goals of this research are twofold: (1) to register event-related potentials (ERP) in the brain in the process of visual and auditory recognition of Russian imitative words on different de-iconization stages; and (2) to establish whether differences in the brain activity arise while processing visual and auditory stimuli of different nature. Sound imitative (onomatopoeic, mimetic, and ideophonic) words are words with iconic correlation between form and meaning (iconicity being a relationship of resemblance). Russian adult participants (n = 110) were presented with 15 stimuli both visually and auditorily. The stimuli material was equally distributed into three groups according to the criterion of (historical) iconicity loss: five explicit sound imitative (SI) words, five implicit SI words and five non-SI words. It was established that there was no statistically significant difference between visually presented explicit or implicit SI words and non-SI words respectively. However, statistically significant differences were registered for auditorily presented explicit SI words in contrast to implicit SI words in the N400 ERP component, as well as implicit SI words in contrast to non-SI words in the P300 ERP component. We thoroughly analyzed the integrative brain activity in response to explicit IS words and compared it to that in response to implicit SI and non-SI words presented auditorily. The data yielded by this analysis showed the N400 ERP component was more prominent during the recognition process of the explicit SI words received from the central channels (specifically Cz). We assume that these results indicate a specific brain response associated with directed attention in the process of performing cognitive decision making tasks regarding explicit and implicit SI words presented auditorily. This may reflect a higher level of cognitive complexity in identifying this type of stimuli considering the experimental task challenges that may involve cross-modal integration process.
ABSTRACT
BACKGROUND: computer-based screenings are usually used for early detection of a child's mental development problems. However, there are no such screenings in Russia yet. This study aimed to elaborate scales for rapid monitoring of mental development of 3-year-olds. METHODS: 863 children took part in the study, among them 814 children of the group Norm, 49 children with developmental delay (DD), including 23 children with symptoms of autistic spectrum disorder (ASD). The multifactor study of mental development tool was used as a part of a software complex for longitudinal research for data collection. This study used a set of 233 tasks that were adequate for 3-year-olds. Exploratory and confirmatory factor analysis was used for the elaboration and factor validation of the scales. The structure of the relationship between scales and age was refined using structural equation modeling. RESULTS: as a result of the research, screening scales were elaborated: "Logical reasoning", "Motor skills", "General awareness", "Executive functions". The factor validity and reliability of scales were proved. The high discriminability of the scales in distinguishing the "Norm" and "DD" samples was revealed. The developed test norms take into account the child's age in days and allow identifying a "risk group" with an expected forecast accuracy of at least 90%. The obtained scales meet psychometric requirements for their application and allow creating an online screening system for wide application.
