Constraints on infants' musical rhythm perception: effects of interval ratio complexity and enculturation

Effects of culture-specific experience on musical rhythm perception are evident by 12 months of age, but the role of culture-general rhythm processing constraints during early infancy has not been explored. Using a habituation procedure with 5- and 7-month-old infants, we investigated effects of temporal interval ratio complexity on discrimination of standard from novel musical patterns containing 200-ms disruptions. Infants were tested in three ratio conditions: simple (2:1), which is typical in Western music, complex (3:2), which is typical in other musical cultures, and highly complex (7:4), which is relatively rare in music throughout the world. Unlike adults and older infants, whose accuracy was predicted by familiarity, younger infants were influenced by ratio complexity, as shown by their successful discrimination in the simple and complex conditions but not in the highly complex condition. The findings suggest that ratio complexity constrains rhythm perception even prior to the acquisition of culture-specific biases.     

Beneficial effects of a music listening intervention on neural speech processing in 0–28-month-old children at risk for dyslexia

Familial risk for developmental dyslexia can compromise auditory and speech processing and subsequent language and literacy development. According to the phonological deficit theory, supporting phonological development during the sensitive infancy period could prevent or ameliorate future dyslexic symptoms. Music is an established method for supporting auditory and speech processing and even language and literacy, but no previous studies have investigated its benefits for infants at risk for developmental language and reading disorders. We pseudo-randomized N∼150 infants at risk for dyslexia to vocal or instrumental music listening interventions at 0–6 months, or to a no-intervention control group. Music listening was used as an easy-to-administer, cost-effective intervention in early infancy. Mismatch responses (MMRs) elicited by speech-sound changes were recorded with electroencephalogram (EEG) before (at birth) and after (at 6 months) the intervention and at a 28 months follow-up. We expected particularly the vocal intervention to promote phonological development, evidenced by enhanced speech-sound MMRs and their fast maturation. We found enhanced positive MMR amplitudes in the vocal music listening intervention group after but not prior to the intervention. Other music activities reported by parents did not differ between the three groups, indicating that the group effects were attributable to the intervention. The results speak for the use of vocal music in early infancy to support speech processing and subsequent language development in infants at developmental risk.

Research Highlights

• Dyslexia-risk infants were pseudo-randomly assigned to a vocal or instrumental music listening intervention at home from birth to 6 months of age.
• Neural mismatch responses (MMRs) to speech-sound changes were enhanced in the vocal music intervention group after but not prior to the intervention.
• Even passive vocal music listening in early infancy can support phonological development known to be deficient in dyslexia-risk.

     

Emotional experience in music fosters 18‐month‐olds' emotion–action understanding: a training study

We examine whether emotional experiences induced via music‐making promote infants' use of emotional cues to predict others' action. Fifteen‐month‐olds were randomly assigned to participate in interactive emotion training either with or without musical engagement for three months. Both groups were then re‐tested with two violation‐of‐expectation paradigms respectively assessing their sensitivity to some expressive features in music and understanding of the link between emotion and behaviour in simple action sequences. The infants who had participated in music, but not those who had not, were surprised by music–face inconsistent displays and were able to interpret an agent's action as guided by her expressed emotion. The findings suggest a privileged role of musical experience in prompting infants to form emotional representations, which support their understanding of the association between affective states and action.     

Music acquisition: effects of enculturation and formal training on development

Musical structure is complex, consisting of a small set of elements that combine to form hierarchical levels of pitch and temporal structure according to grammatical rules. As with language, different systems use different elements and rules for combination. Drawing on recent findings, we propose that music acquisition begins with basic features, such as peripheral frequency-coding mechanisms and multisensory timing connections, and proceeds through enculturation, whereby everyday exposure to a particular music system creates, in a systematic order of acquisition, culture-specific brain structures and representations. Finally, we propose that formal musical training invokes domain-specific processes that affect salience of musical input and the amount of cortical tissue devoted to its processing, as well as domain-general processes of attention and executive functioning.     

Interpersonal synchrony increases prosocial behavior in infants

Adults who move together to a shared musical beat synchronously as opposed to asynchronously are subsequently more likely to display prosocial behaviors toward each other. The development of musical behaviors during infancy has been described previously, but the social implications of such behaviors in infancy have been little studied. In Experiment 1, each of 48 14‐month‐old infants was held by an assistant and gently bounced to music while facing the experimenter, who bounced either in‐synchrony or out‐of‐synchrony with the way the infant was bounced. The infants were then placed in a situation in which they had the opportunity to help the experimenter by handing objects to her that she had ‘accidently’ dropped. We found that 14‐month‐old infants were more likely to engage in altruistic behavior and help the experimenter after having been bounced to music in synchrony with her, compared to infants who were bounced to music asynchronously with her. The results of Experiment 2, using anti‐phase bouncing, suggest that this is due to the contingency of the synchronous movements as opposed to movement symmetry. These findings support the hypothesis that interpersonal motor synchrony might be one key component of musical engagement that encourages social bonds among group members, and suggest that this motor synchrony to music may promote the very early development of altruistic behavior. A video abstract of this article can be viewed at http://www.youtube.com/watch?v=IaqWehfDm7c&feature=youtu.be     

The impact of the home musical environment on infants’ language development

There is strong evidence that musical engagement influences children’s language development but little research has been carried out on the relationship between the home musical environment and language development in infancy. The current study assessed musical exposure at home (including parental singing) and language development in 64 infants (8.5–18 months). Results showed that the home musical environment significantly predicted gesture development. For a subgroup of infants’ below 12 months, both parental singing and overall home musical environment score significantly predicted word comprehension. These findings represent the first demonstration that an enriched musical environment in infancy can promote development of communication skills.     

音乐训练对统计学习能力的促进作用

统计学习能力作为快速习得环境中信息规则的先决条件之一,有助于个体以较小的消耗代价适应环境。音乐训练作为一种由多个感官共同参与的强化活动,被广泛认为是有助于提升认知能力的有效手段。随着统计学习在音乐适应中核心地位的确认以及音乐训练效应的反复验证,近年来,陆续有研究在行为表现和脑机制上证实了音乐训练能够增强个体对输入信息中统计规则的敏感性、促进听觉统计学习能力的提升。然而,关于音乐训练能否促进视觉等其他模态的统计学习能力,目前还存在不一致的结果。未来研究还应对跨模态统计学习能力的音乐训练促进效应做进一步探索;也可选用新手被试进行音乐训练干预,以明确音乐训练与各模态统计学习能力增强之间的因果关系。     

Familiarity overrides complexity in rhythm perception: a cross-cultural comparison of American and Turkish listeners

Despite the ubiquity of dancing and synchronized movement to music, relatively few studies have examined cognitive representations of musical rhythm and meter among listeners from contrasting cultures. We aimed to disentangle the contributions of culture-general and culture-specific influences by examining American and Turkish listeners' detection of temporal disruptions (varying in size from 50-250 ms in duration) to three types of stimuli: simple rhythms found in both American and Turkish music, complex rhythms found only in Turkish music, and highly complex rhythms that are rare in all cultures. Americans were most accurate when detecting disruptions to the simple rhythm. However, they performed less accurately but comparably in both the complex and highly complex conditions. By contrast, Turkish participants performed accurately and indistinguishably in both simple and complex conditions. However, they performed less accurately in the unfamiliar, highly complex condition. Together, these experiments implicate a crucial role of culture-specific listening experience and acquired musical knowledge in rhythmic pattern perception.     

Shared musical knowledge in 11‐month‐old infants

Five‐month‐old infants selectively attend to novel people who sing melodies originally learned from a parent, but not melodies learned from a musical toy or from an unfamiliar singing adult, suggesting that music conveys social information to infant listeners. Here, we test this interpretation further in older infants with a more direct measure of social preferences. We randomly assigned 64 11‐month‐old infants to 1–2 weeks’ exposure to one of two novel play songs that a parent either sang or produced by activating a recording inside a toy. Infants then viewed videos of two new people, each singing one song. When the people, now silent, each presented the infant with an object, infants in both conditions preferentially chose the object endorsed by the singer of the familiar song. Nevertheless, infants’ visual attention to that object was predicted by the degree of song exposure only for infants who learned from the singing of a parent. Eleven‐month‐olds thus garner social information from songs, whether learned from singing people or from social play with musical toys, but parental singing has distinctive effects on infants’ responses to new singers. Both findings support the hypothesis that infants endow music with social meaning. These findings raise questions concerning the types of music and behavioral contexts that elicit infants’ social responses to those who share music with them, and they support suggestions concerning the psychological functions of music both in contemporary environments and in the environments in which humans evolved.     

Effects of Kindermusik training on infants’ rhythmic enculturation

Phillips‐Silver and Trainor (2005) demonstrated a link between movement and the metrical interpretation of rhythm patterns in 7‐month‐old infants. Infants bounced on every second beat of a rhythmic pattern with no auditory accents later preferred to listen to an accented version of the pattern with accents every second beat (duple or march meter), whereas infants bounced on every third beat of the same rhythmic pattern preferred to listen to a version with accents every third beat (triple or waltz meter). The present study compared infants participating in Kindermusik classes with infants not participating in music classes. In Kindermusik classes infants receive enriched experience moving to music. Following Western musical norms, the majority of the music samples in the classes are in duple meter. During the preference test, Kindermusik infants listened longer overall, indicating heightened interest in musical rhythms. Both groups listened longer to the accented version that matched how they had been bounced, but only the Kindermusik group showed a stronger preference in the case of duple bouncing than in the case of triple bouncing. We conclude that musical classes for infants can accelerate the development of culture‐specific metrical perception.     

Older but not younger infants associate own‐race faces with happy music and other‐race faces with sad music

We used a novel intermodal association task to examine whether infants associate own‐ and other‐race faces with music of different emotional valences. Three‐ to 9‐month‐olds saw a series of neutral own‐ or other‐race faces paired with happy or sad musical excerpts. Three‐ to 6‐month‐olds did not show any specific association between face race and music. At 9 months, however, infants looked longer at own‐race faces paired with happy music than at own‐race faces paired with sad music. Nine‐month‐olds also looked longer at other‐race faces paired with sad music than at other‐race faces paired with happy music. These results indicate that infants with nearly exclusive own‐race face experience develop associations between face race and music emotional valence in the first year of life. The potential implications of such associations for developing racial biases in early childhood are discussed.     

People and objects affect the quality of vocalizations in infants with down syndrome

The vocalizations of eight infants with Down syndrome were recorded longitudinally in relation to different social and non-social contexts. The infants were observed biweekly from 8 to 24 weeks and monthly up to 40 weeks. At each visit the infants were presented with their mother, a female stranger, and a rattle puppet, each alternately active and passive. Each condition lasted 60 sec. The results showed that by 4 months of age, the infants produced different types of vocal sounds in relation to environmental contexts. They produced significantly more melodic (speechlike) sounds, vocalic (non-speechlike) sounds, and emotional (crying, laughing and fussing) sounds when facing people than objects. By 6 months of age, these utterances began to be distinguished between mother and female stranger and active and passive adults. However, within the communicative context the overall amount of vocalic (non-speechlike) sounds produced was larger than the amount of melodic (speechlike) sounds. It is suggested that this low output of melodic sounds in the overall vocal production of these infants may adversely affect the development of more appropriate vocal behaviour.     

Training of 7-month-old infants’ manual object exploration skills: Effects of active and observational experience

In the present study, a fine motor training was developed and evaluated in which infants were trained to manually explore objects in an advanced manner. Fifty 7-month-old infants were randomly assigned to three different training conditions: (1) to an active manual exploration training, in which they learned to explore objects efficiently, (2) to an observational manual exploration training, in which they observed how an adult performed sophisticated actions on objects, or (3) to a control group receiving no training. The results impressively indicate that infants with a low level of object exploration skill prior to the training showed the most training effects as compared to infants with proficient object exploratory actions. Interestingly, this differential training effect was true for both the active and observational training, highlighting the role of social learning in infancy. Importantly, our study shows for the first time the impact of normal individual variation in infants’ manual object exploration skills on the effects of a fine motor training.     

Origins of the human pointing gesture: a training study

Despite its importance in the development of children’s skills of social cognition and communication, very little is known about the ontogenetic origins of the pointing gesture. We report a training study in which mothers gave children one month of extra daily experience with pointing as compared with a control group who had extra experience with musical activities. One hundred and two infants of 9, 10, or 11 months of age were seen at the beginning, middle, and end of this one‐month period and tested for declarative pointing and gaze following. Infants’ability to point with the index finger at the end of the study was not affected by the training but was instead predicted by infants’ prior ability to follow the gaze direction of an adult. The frequency with which infants pointed indexically was also affected by infant gaze following ability and, in addition, by maternal pointing frequency in free play, but not by training. In contrast, infants’ ability to monitor their partner’s gaze when pointing, and the frequency with which they did so, was affected by both training and maternal pointing frequency in free play. These results suggest that prior social cognitive advances, rather than adult socialization of pointing per se, determine the developmental onset of indexical pointing, but socialization processes such as imitation and adult shaping subsequently affect both infants’ ability to monitor their interlocutor’s gaze while they point and how frequently infants choose to point.     

基于视听双通道的音乐情绪加工机制及情绪类型和音乐经验的影响

为了探讨视听双通道下的音乐情绪加工机制及音乐情绪类型和音乐训练背景对加工机制的影响,本研究采用表达开心和悲伤的音乐表演视频为材料,比较音乐组被试和非音乐组被试在单听觉通道、单视觉通道和视听双通道三种情境下的情绪评定速度、正确率和强度。结果发现：1）视听双通道与单视觉通道差异显著,与单听觉通道差异不显著。2）非音乐组被试对悲伤的评定正确率高于音乐组被试,对开心的评定正确率低于音乐组被试。说明音乐情绪加工的视听双通道整合优势仅相对单视觉通道存在;非音乐组被试对视觉通道情绪信息的变化更敏感,音乐组被试更依赖音乐经验;可在音乐表演时加入协调的视觉通道情绪信息帮助没有音乐训练经验的听赏者。     

Development of the perception of musical relations: semitone and diatonic structure

In the present research we examined the development of sensitivity to two musical relations significant in Western tonal music, the semitone and diatonic structure. Infants and preschool children were tested for their detection of a semitone change in any position of a five-note melody. Two standard melodies were used, one composed of diatonic tones only and the other containing a non-diatonic tone. In Experiment 1, children from 4 to 6 years of age were superior in detecting the semitone change in the diatonic context compared with the nondiatonic context. In Experiment 2, infants 9 to 11 months of age detected the semitone change in all positions, but their performance was not influenced by diatonic context. These findings indicate that infants and children can discriminate a semitone in a musical context and that the priority of diatonic structure emerges by 4 to 6 years of age.     

Development of frontal electroencephalogram (EEG) and heart rate (ECG) responses to affective musical stimuli during the first 12 months of post-natal life

We examined the development of infants' regional electrocortical (EEG) and heart rate (ECG) responses to affective musical stimuli during the first 12 months of post-natal life. Separate groups of infants were seen at 3 (n=33), 6 (n=42), 9 (n=52), and 12 (n=40) months of age at which time regional EEG and ECG responses were continuously recorded during a baseline condition and during the presentation of three orchestral pieces that were known to vary in affective valence and intensity (happy, sad, fear). Overall, there were two important findings. First, we found that although the overall amount of EEG 4-8 Hz power increased between 3 and 12 months, the distribution of EEG power changed across age, with the younger infants (3- and 6-month-olds) showing no difference between frontal and parietal regions, but the older infants (9- and 12-month-olds) showing relatively more activation at frontal than at parietal sites. This development likely reflects the maturation of frontal lobe function. Second, we found that the presentation of affective music significantly increased brain activity at 3 months of age, had seemingly little effect at 6 and 9 months, and significantly attenuated brain activity at 12 months. Findings suggest that there is a clear developmental change in the effect of music on brain activity in the first year, with music having a "calming" influence on infants by the end of the first year of life.     

为什么和声能诱发音乐情感?——音乐协和性的作用及其认知机制

音乐是高级意识活动产生的声音艺术, 对人类的情感表达和交流具有重要意义。作为连接音乐与情绪的核心要素, 协和性的形成原理至今仍然未有定论。人类如何加工多个音符构成的和声?为什么一些和声听起来协和(愉悦), 一些和声听起来不协和(不愉悦)?协和感究竟是自下而上的声学感知还是自上而下的审美体验?从古希腊时代至今, 这些问题就一直吸引着学者的目光。物理学家从协和与不协和的声学区别中寻找答案, 生理学家从听觉生理机制方面分析协和感的产生, 心理学家研究协和音程偏好是与生俱来的还是后天形成的。目前, 音乐协和性的理论内容主要以西方音乐为主, 中国传统民族音乐迫切需要开展相关的实证研究。     

The joint role of trained,untrained, and observed actions at the origins of goal recognition

Recent findings across a variety of domains reveal the benefits of self-produced experience on object exploration, object knowledge, attention, and action perception. The influence of active experience may be particularly important in infancy, when motor development is undergoing great changes. Despite the importance of self-produced experience, we know that infants and young children are eventually able to gain knowledge through purely observational experience. In the current work, three-month-old infants were given experience with object-directed actions in one of three forms and their recognition of the goal of grasping actions was then assessed in a habituation paradigm. All infants were given the chance to manually interact with the toys without assistance (a difficult task for most three-month-olds). Two of the three groups were then given additional experience with object-directed actions, either through active training (in which Velcro mittens helped infants act more efficiently) or observational training. Findings support the conclusion that self-produced experience is uniquely informative for action perception and suggest that individual differences in spontaneous motor activity may interact with observational experience to inform action perception early in life.     

Individual differences in non-clinical maternal depression impact infant affect and behavior during the still-face paradigm across the first year

Maternal depression can significantly impact mothers’ sensitivity to their infants’ needs as well as infants’ social and emotional development. The still-face paradigm (SFP) is widely used to assess infants’ understanding of the contingency between their own behavior and that of their caregivers, as well as infants’ ability to self-regulate arousal levels during sudden changes in maternal responsiveness. Infants of clinically depressed mothers display blunted levels of negative affect compared to infants of non-depressed mothers during the still-face (SF) phase. However, little is known about whether individual differences in elevated, non-clinical levels of maternal depression similarly affect mother-infant interactions. The current study examines the longitudinal effects of non-clinical maternal depression on infant and maternal behaviors during the SFP. Infants (N = 63) were assessed at 5 and 9 months and maternal depression was assessed at 5 months using the Beck Depression Inventory (BDI). Infants of mothers with elevated levels of depression displayed less negative engagement during the SF phase compared to infants of mothers with lower levels of depression. This effect was present at 5 months, but not at 9 months. Findings demonstrate that non-clinical levels of maternal depressive symptomatology can have a significant impact on infants’ affective regulation during the first half of the first year of life, but this does not necessarily have a long-lasting influence later in infancy. Interventions may want to target mothers with non-clinical depression to promote healthy infant social and emotional development.