Word acquisition could be mediated by the neurocognitive mechanism known as fast mapping (FM). It refers to a process of incidental exclusion-based learning and is believed to be a critical mechanism for the rapid build-up of lexicon, although its neural mechanisms are still poorly understood. To investigate the neural bases of this key learning skill, we used event-related potentials (ERPs) and employed an audio-visual paradigm that included a counterbalanced set of familiar and novel spoken word forms presented, in a single exposure, in conjunction with novel and familiar images. To define learning-related brain dynamics, passive auditory ERPs, known to index long-term memory trace activation, were recorded before and after the FM task. Following the single FM learning exposure, we found a significant enhancement in neural activation elicited by the newly trained word form, which was expressed at ~200–400 ms after the word onset. No similar amplitude increase was found either for the native familiar word used as a control stimulus in the same learning paradigm or for similar control stimuli which were not subject to training. Topographic analysis suggested a left-lateral shift of the ERP scalp distribution for the novel FM word form, underpinned by fronto-temporal cortical sources, which may indicate the involvement of pre-existing neurolinguistic networks for mastering new word forms with native phonology. Overall, the near-instant changes in neural activity after a single-shot novel word training indicate that FM could promote rapid integration of newly learned items into the brain’s neural lexicon, even in adulthood.

This study examined the effect of a social–emotional intervention implemented in one St. Petersburg (Russian Federation) institution (called a Baby Home, BH) on the general behavioral development of preterm children (gestational ages of 30–36 weeks) during their first 2 years of life. The intervention consisted of training caregivers and implementing structural changes to create a more family-like environment. The study included preterm (N = 56) and full-term (N = 93) children from one BH that implemented the intervention and from another BH with no intervention. Children were assessed at 3, 6, 9, 12, 18, and 24 months of age with the Battelle Development Inventory (^{LINC Associates, 1988}). The results showed that the intervention positively influenced the general behavioral development of BH preterm children throughout their first 2 years of life compared with preterm children from the no intervention BH. Also, results indicated that the intervention effect was developmentally similar for preterm and for full-term children, but preterm children consistently scored lower than full-term children during their first 2 years living in the BH. In general, our research emphasizes the crucial role of warm, sensitive, and responsive interactions with a constant and emotionally available caregiver for healthy child development for both term and preterm children.

Prematurity is one of the most crucial risk factors negatively affecting the maturation of the auditory system. Children born preterm demonstrate high rates of hearing impairments. Auditory processing difficulties in preterm children might be a result of disturbances in the central auditory system development and/or sensory deprivation due to peripheral hearing loss. To investigate auditory processing in preterm children, we utilized a set of psychoacoustic tests to assess temporal processing and speech intelligibility. A total of 241 children aged 6–11 years old (136 born preterm and 105 healthy full-term children forming the control group) were assessed. The preterm children were divided into three groups based on their peripheral hearing status: 74 normal hearing (NH group); 30 children with bilateral permanent sensorineural hearing loss (SNHL group) and 32 children with bilateral auditory neuropathy spectrum disorder (ANSD group). The results showed significantly worse performance in all tests in premature children compared with full-term children. NH and SNHL groups showed significant age-related improvement in speech recognition thresholds in noise that might signify a “bottom-up” auditory processing maturation effect. Overall, all premature children had signs of auditory processing disorders of varying degrees. Analyzing and understanding the auditory processing specificity in preterm children can positively contribute to the more effective implementation of rehabilitation programs.

Objective. Systematization and generalization of research data on the impact of early institutionalization on biological indicators of children's development, and a description of the underlying physiological mechanisms and relations between biological indicators and their behavioral manifestations in children. Background. Early deprivation is a significant social-psychological factor that dramatically affects the subsequent mental health and development of children. To date, a wide amount of data on the biological effects of early institutional deprivation has been accumulated in the research literature while this information is little represented in Russia. To understand the specificity of the biological and behavioral development of children with institutionalization experience transferred from Russian institutions into domestic adoptive or foster care families there is a need to analyze, systematize and generalize information on bio-behavioral consequences of early institutionalization. Conclusions. Research results indicate in children with early institutional experience a significant change in biological development manifested in negative changes in morphofunctional development and microstructural organization of the brain, and characteristics of its activity, in cortisol secretion, violations of immunity, changes in DNA methylation profiling, in microbiome. Biological changes and their behavioral correlates are associated with such institutional conditions as the severity of deprivation and duration of institutionalization (the age of the child's transfer from institution to family). In order to prevent developmental, somatic and mental health disorders associated with the long-term impact of early deprivation, the state policy in the field of early childhood and the work of the professional society have to fulfil the rights of the child to live in the family in relationship with sensitive and responsive emotionally available primary caregivers.

Rapid acquisition of new words and construction of large vocabularies is a unique capacity of developing human brain. This process is to a large degree mediated by a neurocognitive mechanism known as «fast mapping» (FM) which allows the child to quickly map new words onto neural representations after even a single exposure to them, using context-driven inference. However, the neurophysiological bases of this mechanism are still poorly understood. To address this open question, we used event-related potentials (ERPs) to investigate brain dynamics elicited by novel words following a single-shot audiovisual semantic learning task and to estimate cortical underpinnings of this process in healthy preschool children. We found that a single presentation of novel words in association with novel objects leads to a decrease in the brain’s activation, registered as an early N400 effect for newly learnt word forms, indicating rapid lexicosemantic memory trace formation in the developing brain. Interestingly, source analysis indicated this effect to be chiefly underpinned by activity modulations in the right-hemispheric temporal cortices, indicating their involvement in speech processing at an early age (known to be diminished later in life). Overall, current findings provide the electrophysiological evidence of the specific mechanism in the developing brain that promotes rapid integration of novel word representations into neocortical lexicosemantic networks after a single exposure, subserving efficient native word acquisition and mastering the mother tongue.