Search Results (6)

Humming is a ubiquitous yet understudied form of human vocalisation that may play a role in regulating internal bodily states during early development. Unlike speech or singing with lyrics, humming consists of continuous, semantically unstructured vocal sounds produced with a closed mouth. It generates sustained sonic, vibratory and respiratory patterns that engage interoceptive and autonomic processes. This paper explores the hypothesis that humming critically contributes to homeostatic regulation in caregiver–infant interaction. Drawing on research in developmental psychology, perinatal care and vocal practice, we propose that humming provides a simple mechanism through which caregivers may scaffold the infant’s developing interoceptive awareness, paving the way to subsequent social cognition abilities. Through slow rhythmic breathing, chest and cranial vibration, and temporally structured vocal phrasing, humming may influence cardio-respiratory rhythms and support autonomic balance while also organising moments of social engagement. Evidence is gathered from studies of maternal humming during kangaroo care with preterm infants, showing that these vocalisations can stabilise physiological parameters and invite infant vocal participation. We argue that humming may function as an embodied, interoceptive form of co-regulation for both infants and caregivers, linking physiological homeostasis with early communicative exchange. Full article

Aim: We compared early vocal development in children “at risk” for cerebral palsy (CP) with typically developing (TD) infants aged 6 to 15 months using the SAEVD-R, investigating potential pre-linguistic markers of communication impairment. Additionally, we sought to examine the agreement between the SAEVD-R and IMP, which uses parent report, in identifying departure from typical vocal development in at-risk infants. Method: Utilising a longitudinal cohort study, >10,000 vocalisations of 33 infants (15 at risk for CP and 18 TD) were assessed at 6, 9, 12, and 15 months using the SAEVD-R. Generalised linear mixed models (GLMMs) compared groups, and Spearman correlations explored IMP ceiling scores and SAEVD-R measures. Results: At 6 months, both TD and CP groups reached SAEVD-R vocalisation level 3 (expansion). By 9 months, 51% of TD infants progressed to advanced babbling (levels 4 and 5), while 80% of at-risk infants remained at level 3. At 12 and 15 months, over 90% of TD children advanced, compared to 67% at 12 months and 53% at 15 months for at-risk infants, who stayed at the pre-canonical stage. Strong correlations were found between IMP scores and vocalisation levels at 9 and 12 months. Remaining at the pre-canonical stage at 12 months correlated with delayed vocal development as per IMP scores. Interpretation: TD infants achieved higher SAEVD-R levels than at-risk infants. At 12 months, IMP scores effectively identified infants with speech-like vocalisation difficulties, demonstrating its clinical utility in identifying atypical vocal development in infants at risk for CP. Full article

The implementation of an intervention protocol aimed at increasing vocal complexity in three pre-linguistic children with cerebral palsy (two males, starting age 15 months, and one female, starting age 16 months) was evaluated utilising a repeated ABA case series design. The study progressed until the children were 36 months of age. Weekly probes with trained and untrained items were administered across each of three intervention blocks. Successive blocks targeted more advanced protophone production and speech movement patterns, individualised for each participant. Positive treatment effects were seen for all participants in terms of a greater rate of achievement of target protophone categories and speech movement patterns. Tau coefficients for trained items demonstrated overall moderate to large AB phase contrast effect sizes, with limited evidence of generalisation to untrained items. Control items featuring protophones and speech movements not targeted for intervention showed no change across phases for any participant. Our data suggest that emerging speech-production skills in prelinguistic infants with CP can be positively influenced through a multimodal intervention focused on capitalising on early periods of plasticity when language learning is most sensitive. Full article

Prematurity deprives infants of the prenatal sensory stimulation essential to their correct development; in addition, the stressful environment of the NICU impacts negatively on their growth. The purpose of this review was to investigate the effects of NICU noise pollution on preterm infants and parents. We focused on the systems and projects used to control and modulate sounds, as well as on those special devices and innovative systems used to deliver maternal sounds and vibrations to this population. The results showed beneficial effects on the preterm infants in different areas such as physiological, autonomic, and neurobehavioral development. Although most of these studies highlight positive reactions, there is also a general acknowledgement of the current limits: small and heterogeneous groups, lack of structured variable measurements, systematic control groups, longitudinal studies, and normative values. The mother’s presence is always preferred, but the use of music therapy and the devices analyzed, although not able to replace her presence, aim to soften her absence through familiar and protective stimuli, which is a very powerful aid during the COVID-19 pandemic. Full article

The social context in which a salient human vocalisation is heard shapes the affective information it conveys. However, few studies have investigated how visual contextual cues lead to differential processing of such vocalisations. The prefrontal cortex (PFC) is implicated in processing of contextual information and evaluation of saliency of vocalisations. Using functional Near-Infrared Spectroscopy (fNIRS), we investigated PFC responses of young adults (N = 18) to emotive infant and adult vocalisations while they passively viewed the scenes of two categories of environmental contexts: a domestic environment (DE) and an outdoors environment (OE). Compared to a home setting (DE) which is associated with a fixed mental representation (e.g., expect seeing a living room in a typical house), the outdoor setting (OE) is more variable and less predictable, thus might demand greater processing effort. From our previous study in Azhari et al. (2018) that employed the same experimental paradigm, the OE context was found to elicit greater physiological arousal compared to the DE context. Similarly, we hypothesised that greater PFC activation will be observed when salient vocalisations are paired with the OE compared to the DE condition. Our finding supported this hypothesis: the left rostrolateral PFC, an area of the brain that facilitates relational integration, exhibited greater activation in the OE than DE condition which suggests that greater cognitive resources are required to process outdoor situational information together with salient vocalisations. The result from this study bears relevance in deepening our understanding of how contextual information differentially modulates the processing of salient vocalisations. Full article

We tested whether dogs and 14–16-month-old infants are able to integrate intersensory information when presented with conspecific and heterospecific faces and vocalisations. The looking behaviour of dogs and infants was recorded with a non-invasive eye-tracking technique while they were concurrently presented with a dog and a female human portrait accompanied with acoustic stimuli of female human speech and a dog’s bark. Dogs showed evidence of both con- and heterospecific intermodal matching, while infants’ looking preferences indicated effective auditory–visual matching only when presented with the audio and visual stimuli of the non-conspecifics. The results of the present study provided further evidence that domestic dogs and human infants have similar socio-cognitive skills and highlighted the importance of comparative examinations on intermodal perception. Full article