Fetal learning: a prospective randomized controlled study

The impact of sound stimulations during pregnancy on fetal learning: a systematic review

BACKGROUND

The developing nervous system in utero is exposed to various stimuli with effects that may be carried forward to the neonatal period. This study aims to investigate the effects of sound stimulation (music and speech) on fetal memory and learning, which was assessed later in neonatal period.

METHODS

The MEDLINE (pubmed), Scopus, EMBASE, and Cochrane Library were searched. Two reviewers selected the studies and extracted the data independently. The quality of eligible studies was assessed using The Joanna Briggs Institute Critical Appraisal Checklist for Randomized Controlled Trials (RCTs).

RESULTS

Overall 3930 articles were retrieved and eight studies met the inclusion criteria. All of the included studies had good general quality; however, high risk of selection and detection bias was detected in most of them. Fetal learning was examined through neonatal electrocardiography (ECG), electroencephalography (EEG), habituation tests, and behavioral responses. Seven studies showed that the infants had learned the fetal sound stimulus and one study indicated that the prenatally stimulated infants performed significantly better on a neonatal behavior test. There was considerable diversity among studies in terms of sound stimulation type, characteristics (intensity and frequency), and duration, as well as outcome assessment methods.

CONCLUSIONS

Prenatal sound stimulation including music and speech can form stimulus-specific memory traces during fetal period and effect neonatal neural system. Further studies with precisely designed methodologies that follow safety recommendations, are needed.

Prenatal Learning and Memory: Review on the Impact of Exposure

BACKGROUND

Prenatal Learning is a topic still debated for its existence, although the concept is well known since ancient times.

OBJECTIVE

The present review highlights the impact of various stimuli on learning and memory in prenatal and postnatal life.

METHODS

For review, various articles from preclinical and clinical studies providing early pieces of evidence of prenatal learning to date were included based on the relevancy of the databases, namely, Scopus, Pubmed, and Google Scholar.

RESULTS

Learning is the process of acquiring skills/ preferences/ habits from the experiences of the exposures of the past. These exposures are the stimuli, which help in categorizing learning into associated or nonassociated learning. The stimuli of adults related to auditory, gustatory, olfactory, visual, touch, etc. are also accessible to the prenatal life in utero either directly or indirectly through the mother. The effects of these stimuli are remarkable during prenatal life and can be seen clearly in infants. These stimuli play an important role in prenatal learning and contribute to neuronal development. The present review summarizes the pieces of evidence for each of these types of learning & their impact on the ex utero life, a futuristic view & the scope of understanding prenatal learning. The review also elucidates the factors affecting prenatal learning.

CONCLUSION

Studies from clinical and preclinical studies reflected the impacts of several aspects of an infant's life and the memory created during prenatal life was found to be most likely carried on to postnatal life.

Effects of music exposure during pregnancy on maternal behavior in mother rats

Several studies have demonstrated the possibility of positive effects of exposure to music during pregnancy on mental function in humans and animals. Although there remains a core belief in the positive effects of music during pregnancy, the underlying neurobehavioral mechanisms of these effects remain unknown. In this study, we aimed to clarify the relationship between maternal nurturing behavior and the oxytocinergic system to elucidate the effect of music on mental health during pregnancy in an experimental investigation using animal models. Pregnant rats were exposed to Mozart sonatas, and their nurturing behavior after delivery was assessed using behavioral analyses. The neural activities of the oxytocinergic system, which are associated with nurturing behavior, were investigated using FosB immunohistochemistry. Music during pregnancy significantly increased the licking behavior of mothers towards pups, which is representative of positive nurturing behavior. In contrast, this alteration in maternal behavior was shown to have no marked effect on the structure or activity of the oxytocinergic system. This study provided possible evidence that exposure to music during pregnancy had a positive effect on postnatal maternal behavior. The results also suggest that the oxytocinergic system, considered a strong candidate for the neural system that regulates maternal behavior, may not be associated with this behavioral change. Understanding the relationship between other neural systems, physiological responses, and nurturing behaviors will provide a more comprehensive explanation of the mechanisms by which music exposure during pregnancy has a positive effect on mental health.

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Pregnant rats were exposed to Mozart sonatas and their nurturing behavior was investigated.

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Exposure to music during pregnancy has a positive effect on postnatal maternal behavior.

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Maternal behavior had no marked effect on the structure or activity of the oxytocinergic neurons.

A Dynamical, Radically Embodied, and Ecological Theory of Rhythm Development

Musical rhythm abilities-the perception of and coordinated action to the rhythmic structure of music-undergo remarkable change over human development. In the current paper, we introduce a theoretical framework for modeling the development of musical rhythm. The framework, based on Neural Resonance Theory (NRT), explains rhythm development in terms of resonance and attunement, which are formalized using a general theory that includes non-linear resonance and Hebbian plasticity. First, we review the developmental literature on musical rhythm, highlighting several developmental processes related to rhythm perception and action. Next, we offer an exposition of Neural Resonance Theory and argue that elements of the theory are consistent with dynamical, radically embodied (i.e., non-representational) and ecological approaches to cognition and development. We then discuss how dynamical models, implemented as self-organizing networks of neural oscillations with Hebbian plasticity, predict key features of music development. We conclude by illustrating how the notions of dynamical embodiment, resonance, and attunement provide a conceptual language for characterizing musical rhythm development, and, when formalized in physiologically informed dynamical models, provide a theoretical framework for generating testable empirical predictions about musical rhythm development, such as the kinds of native and non-native rhythmic structures infants and children can learn, steady-state evoked potentials to native and non-native musical rhythms, and the effects of short-term (e.g., infant bouncing, infant music classes), long-term (e.g., perceptual narrowing to musical rhythm), and very-long term (e.g., music enculturation, musical training) learning on music perception-action.

The effect of prenatal music therapy on fetal and neonatal status: A systematic review and meta-analysis

OBJECTIVES

This study aims to investigate the effects of prenatal music therapy on fetal and neonatal status.

DESIGN AND SETTING

A systematic review and meta-analysis of randomized controlled trials.

INTERVENTIONS

Ovid MEDLINE, Embase, Web of Science, Cochrane Library, and Chinese Biomedical Literature Database were searched for studies investigating the effects of prenatal music therapy. Two independent investigators carried out the literature selection, data analysis, and evidence quality assessment. Eligible studies were qualitatively described and synthesized using meta-analyses.

MAIN OUTCOME MEASURES

The outcomes included fetal or neonatal status.

RESULTS

After screening the 821 records yielded by the systematic search, we identified nine eligible studies involving 1419 pregnant women. Eight studies were included in the meta-analysis, and three outcomes were synthesized. Compared with no music therapy, prenatal music therapy did not change fetal heart rate (mean difference [95 % CI]: -0.28 [-3.75-3.20] beat/min, P = 0.88, moderate quality), number of fetal movements (mean difference [95 % CI]: 0.50 [-0.79-1.78] time/min, P = 0.45, low quality), or number of accelerations (mean difference [95 % CI]: 0.16 [-0.87-1.19] time/min, P = 0.76, low quality). This result did not change when two studies with a high risk of bias were excluded. Subgroup analysis showed that prenatal music therapy did not change fetal heart rate, number of fetal movements, or number of accelerations in different intervention phases.

CONCLUSIONS

Prenatal music therapy might not change fetal and neonatal status. However, more systematic strategies of prenatal music therapy deserve further exploration.

The Fetal Origins of Human Psychological Development

The human fetus holds the key to unlocking the initial origins and predispositions of all aspects of human psychological development. Despite this, difficulties related to experimentally manipulating the behavior of the fetus to assess capacities have sidelined the fetus within the developmental sciences. Instead, the focus has been on the human infant. With new developments in the fields of obstetrics, medical physics, and psychology, the methodological constraints surrounding research on the human fetus are now reduced. We highlight new approaches and indicate possible new directions in the understanding of the cognitive and perceptual capacities of the human fetus.

Memory Traces Formed in Utero-Newborns' Autonomic and Neuronal Responses to Prenatal Stimuli and the Maternal Voice

In our pilot study, we exposed third-trimester fetuses, from week 34 of gestation onwards, twice daily to a maternal spoken nursery rhyme. Two and five weeks after birth, 34 newborns, who were either familiarized with rhyme stimulation in utero or stimulation naïve, were (re-)exposed to the familiar, as well as to a novel and unfamiliar, rhyme, both spoken with the maternal and an unfamiliar female voice. For the stimulation-naïve group, both rhymes were unfamiliar. During stimulus presentation, heart rate activity and high-density electroencephalography were collected and newborns’ responses during familiar and unfamiliar stimulation were analyzed. All newborns demonstrated stronger speech–brain coupling at 1 Hz during the presentation of the maternal voice vs. the unfamiliar female voice. Rhyme familiarity originating from prenatal exposure had no effect on speech–brain coupling in experimentally stimulated newborns. Furthermore, only stimulation-naïve newborns demonstrated an increase in heart rate during the presentation of the unfamiliar female voice. The results indicate prenatal familiarization to auditory speech and point to the specific significance of the maternal voice already in two- to five-week-old newborns.

Sleep, Little Baby: The Calming Effects of Prenatal Speech Exposure on Newborns' Sleep and Heartrate

In a pilot study, 34 fetuses were stimulated daily with a maternal spoken nursery rhyme from week 34 of gestation onward and re-exposed two and five weeks after birth to this familiar, as well as to an unfamiliar rhyme, both spoken with the maternal and an unfamiliar female voice. During auditory stimulation, newborns were continuously monitored with polysomnography using video-monitored hdEEG. Afterward, changes in sleep–wake-state proportions during familiar and unfamiliar voice stimulation were analyzed. Our preliminary results demonstrate a general calming effect of auditory stimulation exclusively in infants who were prenatally “familiarized” with a spoken nursery rhyme, as evidenced by less waking states, more time spent in quiet (deep) sleep, and lower heartrates. A stimulation naïve group, on the other hand, demonstrated no such effects. Stimulus-specific effects related to the familiarity of the prenatally replayed voice or rhyme were not evident in newborns. Together, these results suggest “fetal learning” at a basic level and point to a familiarization with auditory stimuli prior to birth, which is evident in the first weeks of life in behavioral states and heartrate physiology of the newborn.

Subcortico-Cortical Functional Connectivity in the Fetal Brain: A Cognitive Development Blueprint

Recent evidence has shown that patterns of cortico-cortical functional synchronization are consistently traceable by the end of the third trimester of pregnancy. The involvement of subcortical structures in early functional and cognitive development has never been explicitly investigated, notwithstanding their pivotal role in different cognitive processes. We address this issue by exploring subcortico-cortical functional connectivity at rest in a group of normally developing fetuses between the 25th and 32nd weeks of gestation. Results show significant functional coupling between subcortical nuclei and cortical networks related to: (i) sensorimotor processing, (ii) decision making, and (iii) learning capabilities. This functional maturation framework unearths a Cognitive Development Blueprint, according to which grounding cognitive skills are planned to develop with higher ontogenetic priority. Specifically, our evidence suggests that a newborn already possesses the ability to: (i) perceive the world and interact with it, (ii) create salient representations for the selection of adaptive behaviors, and (iii) store, retrieve, and evaluate the outcomes of interactions, in order to gradually improve adaptation to the extrauterine environment.

The effect of prenatal exposure to music on fetal movements and fetal heart rate: a pilot study

OBJECTIVE

To assess and compare fetal cardiac parameters of fetuses listening to music before and during nonstress test, only during the test or never.

STUDY DESIGN

Thirty healthy mother-fetus dyads were randomized in a 1:1:1 ratio to one of three groups: group A in which fetuses were submitted to prelistening phase (33rd + 0 to 36th + 3 week) and listening sessions during 4 nonstress tests, group B in which fetuses were submitted to listening sessions during 4 nonstress tests, and group C receiving 4 nonstress tests without any listening. We assessed mean fetal heart rate, fetal heart rate accelerations, fetal heart rate decelerations, fetal movements and uterine contractility.

RESULTS

Fetuses of the group A, who had already listened to a particular piece of music during previous sessions, had significantly increased their heart rate accelerations and movements during the music listening session of the last nonstress test. No significant changes were observed in the number of uterine contractions.

CONCLUSIONS

Our findings show that fetuses slightly respond to that music they know, but they do not significantly respond to unknown music.

Regular Music Exposure in Juvenile Rats Facilitates Conditioned Fear Extinction and Reduces Anxiety after Foot Shock in Adulthood

Music exposure is known to play a positive role in learning and memory and can be a complementary treatment for anxiety and fear. However, whether juvenile music exposure affects adult behavior is not known. Two-week-old Sprague-Dawley rats were exposed to music for 2 hours daily or to background noise (controls) for a period of 3 weeks. At 60 days of age, rats were subjected to auditory fear conditioning, fear extinction training, and anxiety-like behavior assessments or to anterior cingulate cortex (ACC) brain-derived neurotrophic factor (BDNF) assays. We found that the music-exposed rats showed significantly less freezing behaviors during fear extinction training and spent more time in the open arm of the elevated plus maze after fear conditioning when compared with the control rats. Moreover, the BDNF levels in the ACC in the music group were significantly higher than those of the controls with the fear conditioning session. This result suggests that music exposure in juvenile rats decreases anxiety-like behaviors, facilitates fear extinction, and increases BDNF levels in the ACC in adulthood after a stressful event.

The human newborn's umwelt: Unexplored pathways and perspectives

Historically, newborns, and especially premature newborns, were thought to "feel nothing." However, over the past decades, a growing body of evidence has shown that newborns are aware of their environment, but the extent and the onset of some sensory capacities remain largely unknown. The goal of this review is to update our current knowledge concerning newborns' perceptual world and how ready they are to cope with an entirely different sensory environment following birth. We aim to establish not only how and when each sensory ability arises during the pre-/postbirth period but also discuss how senses are studied. We conclude that although many studies converge to show that newborns are clearly sentient beings, much is still unknown. Further, we identify a series of internal and external factors that could explain discrepancies between studies, and we propose perspectives for future studies. Finally, through examples from animal studies, we illustrate the importance of this detailed knowledge to pursue the enhancement of newborns' daily living conditions. Indeed, this is a prerequisite for assessing the effects of the physical environment and routine procedures on newborns' welfare.

Maternal singing of lullabies during pregnancy and after birth: Effects on mother-infant bonding and on newborns' behaviour. Concurrent Cohort Study

BACKGROUND

Mother-infant bonding is of great importance for the development and the well-being of the baby. The aim of this Concurrent Cohort Study was to investigate the effects of mothers singing lullabies on bonding, newborns' behaviour and maternal stress.

METHODS

Eighty-three (singing cohort) and 85 (concurrent cohort) women were recruited at antenatal classes at 24 weeks g.a. and followed up to 3 months after birth. The Prenatal Attachment Inventory (PAI) and the Mother-to-Infant Bonding Scale (MIBS) were used to assess maternal-foetal attachment and postnatal bonding.

FINDINGS

No significant influence was found on Prenatal Attachment; by contrast, Postnatal Bonding was significantly greater (i.e. lower MIBS) in the singing group 3 months after birth (mean 1.28 vs 1.96; p=0.001). In the same singing group, the incidence of neonatal crying episodes in the first month was significantly lower (18.5% vs 28.2; p<0.0001) as were the infantile colic (64.7% vs 38.3%; p=0.003) and perceived maternal stress (29.6% vs 36.5%; p<0.05). Infantile colic was reduced in the singing group, even in the second month after birth (22.8% vs 36.5; p=0.002). At the same time, a reduction was observed in the neonatal nightly awakening (1.5% vs 4.7; p<0.0001).

CONCLUSIONS

Mothers singing lullabies could improve maternal-infant bonding. It could also have positive effects on neonatal behaviour and maternal stress.

Antenatal Training with Music and Maternal Talk Concurrently May Reduce Autistic-Like Behaviors at around 3 Years of Age

Antenatal training through music and maternal talk to the unborn fetus is a topic of general interest for parents-to-be in China, but we still lack a comprehensive assessment of their effects on the development of autistic-like behaviors during early childhood. During 2014-2016, 34,749 parents of children around the age of 3 years who were enrolled at kindergarten in the Longhua district of Shenzhen participated in this study. Self-administered questionnaires regarding demographics, antenatal music training, and maternal talk to the fetus during pregnancy were completed by the children's primary caregivers. Autistic-like behaviors were assessed using the Autism Behavioral Checklist. Tobit regression analyses revealed that antenatal music training and maternal talk to the fetus was associated with a reduction in autistic-like behaviors in children, with a dose-dependent relationship. Furthermore, factorial analysis of covariance indicated a significant interaction effect between antenatal music training and maternal talk to the fetus on the autistic-like behaviors and found that children who often experienced antenatal music training and maternal talk concurrently had the lowest risk of autistic-like behaviors, while children who were never exposed to maternal talk and only sometimes experienced antenatal music training had the highest risk. Our results suggest that antenatal training through both music and maternal talk to the unborn fetus might reduce the risk of children's autistic-like behaviors at around 3 years of age.

Rhythm perception, production, and synchronization during the perinatal period

Sensori-motor synchronization (SMS) is the coordination of rhythmic movement with an external rhythm. It plays a central role in motor, cognitive, and social behavior. SMS is commonly studied in adults and in children from four years of age onward. Prior to this age, the ability has rarely been investigated due to a lack of available methods. The present paper reviews what is known about SMS in young children, infants, newborns, and fetuses. The review highlights fetal and infant perception of rhythm and cross modal perception of rhythm, fetal, and infant production of rhythm and cross modal production of rhythm, and the contexts in which production of rhythm can be observed in infants. A primary question is whether infants, even newborns, can modify their spontaneous rhythmical motor behavior in response to external rhythmical stimulation. Spontaneous sucking, crying, and leg movements have been studied in the presence or absence of rhythmical auditory stimulation. Findings suggest that the interaction between movement and sound is present at birth and that SMS can be observed in special conditions and within a narrow range of tempi, particularly near the infant's own spontaneous motor tempo. The discussion centers on the fundamental role of SMS in interaction and communication at the beginning of life.

Music and early language acquisition

Language is typically viewed as fundamental to human intelligence. Music, while recognized as a human universal, is often treated as an ancillary ability - one dependent on or derivative of language. In contrast, we argue that it is more productive from a developmental perspective to describe spoken language as a special type of music. A review of existing studies presents a compelling case that musical hearing and ability is essential to language acquisition. In addition, we challenge the prevailing view that music cognition matures more slowly than language and is more difficult; instead, we argue that music learning matches the speed and effort of language acquisition. We conclude that music merits a central place in our understanding of human development.

Maternal Music Exposure during Pregnancy Influences Neonatal Behaviour: An Open-Label Randomized Controlled Trial

Objective. This study evaluated the effect of antenatal music exposure to primigravida healthy mothers on the behaviour of their term appropriate-for-date newborns assessed using Brazelton Neonatal Behavioral Assessment Scale (BNBAS). Methods. This was a single-centre, randomized, open-label controlled trial. Primigravida mothers aged 19–29 years, free of chronic medical diseases or significant deafness, with singleton pregnancy, with a gestation of 20 weeks or less, were randomized to listen to a pre-recorded music cassette for approximately 1 hour/day in addition to standard antenatal care (intervention arm) or standard care only (control arm). Perinatal factors with adverse effect on neonatal behaviour were deemed as protocol violations. Outcome measure included scores on 7 clusters of BNBAS. Primary analysis was per protocol. The trial is registered with ClinicalTrials.gov (NCT01278329). Results. One hundred and twenty-six newborns in the music group and 134 in the control group were subjected to BNBAS assessment. The infants of mothers exposed to music during pregnancy performed significantly better on 5 of the 7 BNBAS clusters. The maximal beneficial effect was seen with respect to orientation (ES 1.13, 95% CI 0.82–1.44, P < 0.0001) and habituation (ES 1.05, 95% CI 0.53–1.57, P = 0.0001). Conclusion. Prenatal music exposure to mother significantly and favourably influences neonatal behaviour.

The role of early auditory development in attachment and communication

Auditory perception and learning take place during the third trimester of gestation. Fetuses and newborns who lack typical auditory experience can go on to develop typical socioemotional attachment and language, given a supportive environment. For hospitalized preterm infants in developmentally sensitive neonatal intensive care units, detrimental effects of deviant early auditory experience may be remediated by later experience, but much is unknown about the causes of language deficits of prematurity. Prenatal auditory stimulation programs that incorporate audio speakers against the maternal belly should be discouraged because of possible overstimulation effects on the developing auditory system and sleep/wake state organization.

A melodic contour repeatedly experienced by human near-term fetuses elicits a profound cardiac reaction one month after birth

BACKGROUND

Human hearing develops progressively during the last trimester of gestation. Near-term fetuses can discriminate acoustic features, such as frequencies and spectra, and process complex auditory streams. Fetal and neonatal studies show that they can remember frequently recurring sounds. However, existing data can only show retention intervals up to several days after birth.

METHODOLOGY/PRINCIPAL FINDINGS

Here we show that auditory memories can last at least six weeks. Experimental fetuses were given precisely controlled exposure to a descending piano melody twice daily during the 35(th), 36(th), and 37(th) weeks of gestation. Six weeks later we assessed the cardiac responses of 25 exposed infants and 25 naive control infants, while in quiet sleep, to the descending melody and to an ascending control piano melody. The melodies had precisely inverse contours, but similar spectra, identical duration, tempo and rhythm, thus, almost identical amplitude envelopes. All infants displayed a significant heart rate change. In exposed infants, the descending melody evoked a cardiac deceleration that was twice larger than the decelerations elicited by the ascending melody and by both melodies in control infants.

CONCLUSIONS/SIGNIFICANCE

Thus, 3-weeks of prenatal exposure to a specific melodic contour affects infants 'auditory processing' or perception, i.e., impacts the autonomic nervous system at least six weeks later, when infants are 1-month old. Our results extend the retention interval over which a prenatally acquired memory of a specific sound stream can be observed from 3-4 days to six weeks. The long-term memory for the descending melody is interpreted in terms of enduring neurophysiological tuning and its significance for the developmental psychobiology of attention and perception, including early speech perception, is discussed.

Julia's placebo effect

Placebo analgesia is the occurrence of an analgesic drug effect without drugs. The response is learned through conditioning and mediated by expectancy. It lies on the up-regulation of the pain-modulating areas and the down-regulation of the pain-encoding regions. A further mechanism is the retrieval of the brain circuit activity previously excited by drugs. We describe the case of an infant affected by a tracheal agenesis who underwent a series of operative and diagnostic bronchoscopies for which she received midazolam and fentanyl. After 61 procedures the infant showed a somatosensory response which in our interpretation reflected a placebo effect. Ontogenetic considerations and specific observations indicate that the infant had the appropriate competences in her learning and memory systems and nociceptive and antinociceptive circuits for the placebo effect to take place. Generalizing, the introduction of placebo manipulation in infant pain management may be taken into consideration; its approach through observational and experimental studies is the preliminary target.

Fetal and neonatal habituation in infants of diabetic mothers

OBJECTIVE

To evaluate whether maternal diabetes alters the habituation ability of fetuses and newborns.

STUDY DESIGN

Two nonrandomized clinical trials were performed. First, we studied prenatal fetuses of women with pregestational diabetes, and control subjects matched for gestational age, and then we studied infants of diabetic mothers (IDM) and control subjects matched for gestational age and mode of delivery. Fetus and newborns were stimulated with vibroacoustic stimulus.

RESULTS

In fetuses of diabetic mothers, the ability to habituate was lower, and the habituation rate was higher than in control subjects to all habituation tests. In the neonatal period, ability to habituate was lower (59% vs 100%; P< .001), and the habituation rate was higher (18 [14-21] vs 4 [1.2-6.8]; P< .001) in the IDM than in the control infants. We found a significant negative correlation between maternal glycosylated hemoglobin in each trimester of pregnancy and habituation ability in IDM.

CONCLUSIONS

Fetuses and infants of diabetic mothers have impaired habituation ability, which is related to the degree of maternal metabolic control.

[Fetal audition. Myth or reality]

Fetal sensory abilities have been considered for a long time as a philosophical question. The aim of this review is to investigate the scientifically proven knowledge about fetal audition. Fetal audition seems to depend on gestational age and sound characteristics. The onset of human fetal hearing is observed at about 26-28 weeks gestational age. Noises from the placenta, the maternal organs and the maternal voice play a major role as current in utero auditory stimuli. Many studies demonstrate that the fetus forms memories of his hearing experiences allowing some authors to use the term "fetal learning". The fetus can memorize not only his mother's voice but also more complex acoustic external sounds with a big ability of discrimination. Moreover, most studies strengthen the hypothesis of an implicit musical ability of the human brain.

Fetal magnetoencephalography

The assessment of the neurological integrity of the human fetus in utero is a technically challenging problem. New brain imaging devices can substantially improve our capabilities to describe functional brain activity in the fetus. It has been well established by fetal behavioral studies and investigations in preterm and term newborns that the brain is functional in utero. The major effort required to perform effective neurological functional investigations is designation of an integrated approach to neurological assessment and the generation of normative data. Currently, it is possible to record evoked brain activity elicited by auditory and visual stimulation from the fetus. In addition, there is growing evidence that spontaneous brain activity can be recorded in the fetus. This paper explores the current status of the brain-imaging field for fetal investigations and currently available data.

Foetal response to music and voice

OBJECTIVE

To examine whether prenatal exposure to music and voice alters foetal behaviour and whether foetal response to music differs from human voice.

SUBJECTS AND METHODS

A prospective observational study was conducted in 20 normal term pregnant mothers. Ten foetuses were exposed to music and voice for 15 s at different sound pressure levels to find out the optimal setting for the auditory stimulation. Music, voice and sham were played to another 10 foetuses via a headphone on the maternal abdomen. The sound pressure level was 105 db and 94 db for music and voice, respectively. Computerised assessment of foetal heart rate and activity were recorded. 90 actocardiograms were obtained for the whole group. One way anova followed by posthoc (Student-Newman-Keuls method) analysis was used to find if there is significant difference in foetal response to music and voice versus sham.

RESULTS

Foetuses responded with heart rate acceleration and motor response to both music and voice. This was statistically significant compared to sham. There was no significant difference between the foetal heart rate acceleration to music and voice.

CONCLUSION

Prenatal exposure to music and voice alters the foetal behaviour. No difference was detected in foetal response to music and voice.

Fetal magnetoencephalography: current progress and trends

Multimodal testing is the key to successful fetal neurological assessment. New mutichannel SQUID (Superconducting Quantum Interference Device) sensor devices can now be used to effectively record fetal auditory evoked responses (fAER) and visual evoked responses (VER), spontaneous brain activity, and heart activity. In this paper, we review the current progress in the area of fetal magnetoencephalography (fMEG) and also present an overview of the studies performed using a system called SARA that is specifically designed for fetal MEG studies. With the capability of recording spontaneous and evoked magnetic fields, we believe the monitoring of the neurological status of the fetus can be effectively implemented and can encourage the development of new strategies of intervention for the high-risk fetus.