No Own-Age Bias in Children’s Gaze-Cueing Effects

Sensitivity to another person’s eye gaze is vital for social and language development. In this eye-tracking study, a group of 74 children (6–14 years old) performed a gaze-cueing experiment in which another person’s shift in eye gaze potentially cued the location of a peripheral target. The aim of the present study is to investigate whether children’s gaze-cueing effects are modulated by the other person’s age. In half of the trials, the gaze cue was given by adult models, in the other half of the trials by child models. Regardless of the models’ ages, children displayed an overall gaze-cueing effect. However, results showed no indication of an own-age bias in the performance on the gaze-cueing task; the gaze-cueing effect is similar for both child and adult face cues. These results did not change when we looked at the performance of a subsample of participants (n = 23) who closely matched the age of the child models. Our results do not allow us to disentangle the possibility that children are insensitive to a model’s age or whether they consider models of either age as equally informative. Future research should aim at trying to disentangle these two possibilities

Brain Responses to Faces and Facial Expressions in 5-Month-Olds: An fNIRS Study

Processing faces and understanding facial expressions are crucial skills for social communication. In adults, basic face processing and facial emotion processing rely on specific interacting brain networks. In infancy, however, little is known about when and how these networks develop. The current study uses functional near-infrared spectroscopy (fNIRS) to measure differences in 5-month-olds’ brain activity in response to fearful and happy facial expressions. Our results show that the right occipital region responds to faces, indicating that the face processing network is activated at 5 months. Yet sensitivity to facial emotions appears to be still immature at this age: explorative analyses suggest that if the facial emotion processing network was active this would be mainly visible in the temporal cortex. Together these results indicate that at 5 months, occipital areas already show sensitivity to face processing, while the facial emotion processing network seems not fully developed

Two-year-olds at elevated risk for ASD can learn novel words from their parents

Children diagnosed with autism spectrum disorder (ASD) often have smaller vocabularies in infancy compared to typically-developing children. To understand whether their smaller vocabularies stem from problems in learning, our study compared a prospective risk sample of 18 elevated risk and 11 lower risk 24-month-olds on current vocabulary size and word learning ability using a paradigm in which parents teach their child words. Results revealed that both groups learned novel words, even though parents indicated that infants at elevated risk of ASD knew fewer words. This suggests that these early compromised vocabularies cannot be solely linked to difficulties in word formations

Social information processing in infancy and adolescence : Examining the role of different interaction partners

Over the course of development children learn vital communication skills from interacting with other people. However, how children learn and react might depend on the person they are interacting with. We therefore investigated the possible role of different interaction partners in two developmental samples - toddlers and adolescents. In the first part of this dissertation I examined whether familiarity of the speaker facilitated novel word learning in both a typical sample of two-year-olds and in children at increased risk for autism. Results for the typical population showed that compared to unfamiliar speakers, maternal speech indeed boosts novel word learning. This was the case both when mothers produced speech during live interaction, and when her speech was prerecorded and delivered through loudspeakers. Given these results, I next asked whether toddlers at increased risk for autism can learn novel words from their parents, as these children are typically reported to have smaller vocabularies. Although my results confirm that these high-risk infants lagged behind in their current vocabulary size compared to typically-developing peers, there was no such group difference in their ability to learn novel words from their parents. This suggests that smaller vocabularies observed in children with autism are unlikely to originate in poor word-object mapping, but rather result from deficiencies in for example consolidation of novel words or on higher level social demands of interactive communication. In the second part we examined the development of social processes over the course of adolescence, as there are extensive changes in social behavior during this period. Because of a re-orientation from parents to peers, adolescents are temporarily relatively worse in recognizing adult faces compared to child faces. I first examined whether such a dip could also be observed in other higher social processes (i.e., gaze following, emotion recognition and empathy). Both emotion recognition and empathy abilities gradually increased over adolescence, whereas gaze following did not change over this period. Thus, in contrast to basic face recognition, I did not observe any dip in performance around the onset of puberty for these higher social processes in which children viewed (parts of) adults’ faces. This begged the question whether age of the interaction partner would influence a child’s gaze following behavior. Results, however, showed similar gaze following patterns for both adult and child stimuli, which highlights that children's responses to gaze cues are not modulated by the age of the interaction partner. Based on the research described in this dissertation, I conclude that the type of interaction partner can shape early social development. Clearly familiarity with the interaction partner plays an important role in infants' language processing. Age of the interaction partner (adult versus peers) does not modulate higher social processing in adolescence. It remains an open question how familiarity affects social processing in adolescence, which is a relevant topic for future research. This knowledge is fundamental for the design of early interventions for children with communicative disorders, as it gives insights on who might be suitable to deliver these interventions to the children

Social information processing in infancy and adolescence : Examining the role of different interaction partners

Over the course of development children learn vital communication skills from interacting with other people. However, how children learn and react might depend on the person they are interacting with. We therefore investigated the possible role of different interaction partners in two developmental samples - toddlers and adolescents. In the first part of this dissertation I examined whether familiarity of the speaker facilitated novel word learning in both a typical sample of two-year-olds and in children at increased risk for autism. Results for the typical population showed that compared to unfamiliar speakers, maternal speech indeed boosts novel word learning. This was the case both when mothers produced speech during live interaction, and when her speech was prerecorded and delivered through loudspeakers. Given these results, I next asked whether toddlers at increased risk for autism can learn novel words from their parents, as these children are typically reported to have smaller vocabularies. Although my results confirm that these high-risk infants lagged behind in their current vocabulary size compared to typically-developing peers, there was no such group difference in their ability to learn novel words from their parents. This suggests that smaller vocabularies observed in children with autism are unlikely to originate in poor word-object mapping, but rather result from deficiencies in for example consolidation of novel words or on higher level social demands of interactive communication. In the second part we examined the development of social processes over the course of adolescence, as there are extensive changes in social behavior during this period. Because of a re-orientation from parents to peers, adolescents are temporarily relatively worse in recognizing adult faces compared to child faces. I first examined whether such a dip could also be observed in other higher social processes (i.e., gaze following, emotion recognition and empathy). Both emotion recognition and empathy abilities gradually increased over adolescence, whereas gaze following did not change over this period. Thus, in contrast to basic face recognition, I did not observe any dip in performance around the onset of puberty for these higher social processes in which children viewed (parts of) adults’ faces. This begged the question whether age of the interaction partner would influence a child’s gaze following behavior. Results, however, showed similar gaze following patterns for both adult and child stimuli, which highlights that children's responses to gaze cues are not modulated by the age of the interaction partner. Based on the research described in this dissertation, I conclude that the type of interaction partner can shape early social development. Clearly familiarity with the interaction partner plays an important role in infants' language processing. Age of the interaction partner (adult versus peers) does not modulate higher social processing in adolescence. It remains an open question how familiarity affects social processing in adolescence, which is a relevant topic for future research. This knowledge is fundamental for the design of early interventions for children with communicative disorders, as it gives insights on who might be suitable to deliver these interventions to the children

Beneficial effects of the mother’s voice on infants’ novel word learning

This dataset contains raw data files of the study "Beneficial effects of the mother’s voice on infants’ novel word learning (under review)". Abstract: For language acquisition, the maternal voice is special as it is the voice infants are most familiar with. The current eye-tracking study investigated whether 24-month-olds (n =149) learn novel words easier while listening to their mothers compared to unfamiliar speakers. Results show that maternal speech facilitates the formation of new word-object mappings across two different settings: a live setting in which an infant is actively taught by the infant’s mother or the experimenter, and a prerecorded setting in which the voice of either the infant’s own or another infant’s mother is played over loudspeakers. Furthermore, this study explored whether infants' pointing gestures and novel word repetitions during task serve as meaningful indexes of word learning behavior. Infants who repeated more target words during task also show a larger learning effect in their looking behavior. Thus, maternal speech as well as infants’ willingness to repeat novel words are positively linked with novel word learning

Beneficial effects of the mother’s voice on infants’ novel word learning

This dataset contains raw data files of the study "Beneficial effects of the mother’s voice on infants’ novel word learning (under review)". Abstract: For language acquisition, the maternal voice is special as it is the voice infants are most familiar with. The current eye-tracking study investigated whether 24-month-olds (n =149) learn novel words easier while listening to their mothers compared to unfamiliar speakers. Results show that maternal speech facilitates the formation of new word-object mappings across two different settings: a live setting in which an infant is actively taught by the infant’s mother or the experimenter, and a prerecorded setting in which the voice of either the infant’s own or another infant’s mother is played over loudspeakers. Furthermore, this study explored whether infants' pointing gestures and novel word repetitions during task serve as meaningful indexes of word learning behavior. Infants who repeated more target words during task also show a larger learning effect in their looking behavior. Thus, maternal speech as well as infants’ willingness to repeat novel words are positively linked with novel word learning

No Own-Age Bias in Children's Gaze-Cueing Effects

Sensitivity to another person’s eye gaze is vital for social and language development. In this eye-tracking study, a group of 74 children (6–14 years old) performed a gaze-cueing experiment in which another person’s shift in eye gaze potentially cued the location of a peripheral target. The aim of the present study is to investigate whether children’s gaze-cueing effects are modulated by the other person’s age. In half of the trials, the gaze cue was given by adult models, in the other half of the trials by child models. Regardless of the models’ ages, children displayed an overall gaze-cueing effect. However, results showed no indication of an own-age bias in the performance on the gaze-cueing task; the gaze-cueing effect is similar for both child and adult face cues. These results did not change when we looked at the performance of a subsample of participants (n = 23) who closely matched the age of the child models. Our results do not allow us to disentangle the possibility that children are insensitive to a model’s age or whether they consider models of either age as equally informative. Future research should aim at trying to disentangle these two possibilities

No Own-Age Bias in Children's Gaze-Cueing Effects

Sensitivity to another person’s eye gaze is vital for social and language development. In this eye-tracking study, a group of 74 children (6–14 years old) performed a gaze-cueing experiment in which another person’s shift in eye gaze potentially cued the location of a peripheral target. The aim of the present study is to investigate whether children’s gaze-cueing effects are modulated by the other person’s age. In half of the trials, the gaze cue was given by adult models, in the other half of the trials by child models. Regardless of the models’ ages, children displayed an overall gaze-cueing effect. However, results showed no indication of an own-age bias in the performance on the gaze-cueing task; the gaze-cueing effect is similar for both child and adult face cues. These results did not change when we looked at the performance of a subsample of participants (n = 23) who closely matched the age of the child models. Our results do not allow us to disentangle the possibility that children are insensitive to a model’s age or whether they consider models of either age as equally informative. Future research should aim at trying to disentangle these two possibilities