Exposure to the parents' speech is positively associated with preterm infant's face preference.

BACKGROUND: The parents' presence and involvement in neonatal care is a promising approach to improve preterm infants' neurodevelopmental outcomes. We examined whether exposure to the parents' speech is associated with the preterm infant's social-cognitive development. METHODS: The study included infants born before 32 gestational weeks in two neonatal units. Each infant's language environment was assessed from 16-hour recordings using Language Environment Analysis (LENA®). Parental presence was assessed with Closeness Diary for 14 days during the hospital stay. Attention to faces and non-face patterns was measured at the corrected age of seven months using an eye-tracking disengagement test. RESULTS: A total of 63 preterm infants were included. Infants were less likely to disengage their attention from faces (M = 0.55, SD = 0.26) than non-face patterns (M = 0.24, SD = 0.22), p < 0.001, d = 0.84. Exposure to the parents' speech during the neonatal period was positively correlated with the preference for faces over non-face patterns (rs = 0.34, p = 0.009) and with the preference for parents over unfamiliar faces (rs = 0.28, p = 0.034). CONCLUSION: The exposure to the parents' speech during neonatal hospital care is a potential early marker for later social development in preterm infants. IMPACT: The exposure to the parents' speech during neonatal intensive care is a potential early marker for optimal social-cognitive development in preterm infants. This is the first study to show an association between parental vocal contact during neonatal intensive care and early social development (i.e., face preference), measured at seven months of corrected age. Our findings suggest that we should pay attention to the parents' vocal contact with their child in the neonatal intensive care unit and identify need for tailored support for face-to-face and vocal contact.

Language environment and parent-infant close contact in neonatal care and emerging lexical abilities of very preterm children-a longitudinal study.

AIM: This longitudinal study investigated associations between language environment and parent-infant close contact in the neonatal intensive care unit (NICU) and preterm children's lexical abilities. METHODS: NICU language environment of 43 very preterm infants (born<32 gestational weeks) was measured with the Language Environment Analysis System (LENA; variables: number of adult words, conversational turns, and child vocalisations). Parent-infant close contact (holding and skin-to-skin contact) in the NICU was reported using parental closeness diaries. At 15 and 18 months' corrected age, lexical development was measured with screening methods, and eye tracking-based lexical processing was assessed at 18 months. N varied between 29 and 38 in different outcome measures. RESULTS: LENA measured conversational turns and child vocalisations, and parent-infant close contact associated positively with lexical development (r = 0.35-0.57). High numbers of NICU adult words associated negatively with lexical processing (r = -0.38- -0.40). In regression models, conversational turns and parent-infant close contact explained 34%-35% of receptive development. CONCLUSION: Findings suggest that adult-infant turn taking and parent-infant close contact in the NICU are positively associated with lexical development. High numbers of overheard words in the NICU may not favour later lexical processing. Further research is warranted on the significance of NICU language environment on later lexical abilities.

Eye tracking based assessment of lexical processing and early lexical development in very preterm children.

BACKGROUND: Associations between lexical processing and lexical development during the second year of life have been little studied in preterm children. AIMS: To evaluate associations between lexical processing at 18 months and lexical development between 12 and 18 months in very preterm children. STUDY DESIGN: Correlational study. SUBJECTS: 25 Finnish-speaking children born <32 gestational weeks. OUTCOME MEASURES: Lexical processing (reaction time RT; correct looking time CLT) was measured with an eye tracking technology-based task at 18 months' corrected age. Lexical development was measured longitudinally at 12-, 15- and 18-months' corrected age using the following screening instruments: the short form version of the MacArthur Communicative Development Inventories and the Communication and Symbolic Behavior Scale: Infant-Toddler Checklist. RESULTS: The longer the RT of the child, the weaker expressive skills the child had at 12 and 15 months (correlations coefficient values -0.45 to -0.51). The more the child looked at the target image compared to the distractor (CLT), the stronger expressive skills the child had at 18 months (r = 0.45-0.52). A linear regression model with RT and gender as independent variables explained 33 % of the variance in lexical skills at 18 months. A model with CLT explained 40 % of expressive skills at 18 months. CONCLUSIONS: Lexical processing at 18 months was associated with expressive lexical development in very preterm children. The results suggest eye tracking technology based methods may have utility in the assessment of early lexical growth in preterm children, although further research is needed to assess psychometric properties and predictive value of the method.

The validity of the Language Environment Analysis system in two neonatal intensive care units.

AIM: To evaluate the validity of the Language Environment Analysis (LENA) system's automatic measures in two neonatal intensive care units supporting parent-infant closeness, and in two Finno-Ugric languages: Finnish and Estonian. METHODS: The sound environment of 70 very preterm infants was recorded for 16 h in the neonatal intensive care units with the LENA system roughly at the gestational age of 32 (+2) weeks. Of these, the recordings of 14 infants (20%, two 5-min samples with a high percentage of speech, totally 140 min) were analysed in detail and in two different ways. Parental closeness diaries were used to document the presence of the parents. Agreements between LENA system and human coder estimates were analysed. RESULTS: Findings showed a high variation in agreements. The highest agreements were found in female and adult word counts (r = 0.91 and 0.95). The agreements for child vocalisation count, conversational turns and silence were modest or low (r = -0.03 to 0.64). CONCLUSION: Our study provides novel information on the validity of the LENA system in the neonatal intensive care unit. Findings show that the LENA system provides valid information on adult words, but LENA estimates for child vocalisations were less valid at this early age.