“Music was my first love, it will be my last. Music of the future, music of the past.” This text of the song of John Miles holds true for many of us independent of our cultural background.  Music has always existed and has profoundly affected humans in our physical, mental, emotional and spiritual well-being.  However, it is only in recent years that parents as well as scientists have become increasingly interested in the way music may influence us before we are even born.  Truthfully, I have never seriously considered the mysteries of fetal sound awareness before my pregnancy.  Now, being a first-time pregnant mother-to-be, I resolved to delve deeper into the recent studies that surround the effects of music on early development in the womb.  A vast majority of people think that babies that are stimulated by music before birth tend to exhibit accelerated visual, linguistic, and motor development.  Although most studies do not support the common belief that playing music to fetuses and infants increases their overall intelligence, experts agree that music and sound stimulation does alter fetal behavior and can benefit a prenate if used correctly.

The sense of hearing is probably the most developed of all senses before birth.  The ear first appears in the 3^rd week of pregnancy, and it becomes functional by the 16^th week. A healthy, normally developing fetus can begin hearing by the 24^th week of gestation.  From ultrasound observations, it is evident that the fetus hears and responds to a sound pulse starting about 16 weeks of age (Shahidullah). Surprisingly, this is even before the ear construction is fully complete.  According to another study, by about 30 weeks fetuses begin to respond to brief episodes (2–3 seconds) of relatively loud sounds with heart rate acceleration and body movement. (Kisilevsky). As gestation advances, the frequency and magnitude of responses increases and the threshold necessary to cause the responses decreases. Clearly, by late gestation the fetus can hear, and fetal auditory perceptual abilities become more sensitive as the auditory system matures.

A mother’s womb provides a pretty safe auditory environment for a growing baby. A common interpretation of noise level uses decibels (dB) as a measure of sound intensity or loudness. For instance, a whisper can register 30 dB, a normal conversation is about 60 dB, and rush hour traffic can average to about 70 dB. On the other hand, shouted conversations and motorcycles reach about 100 dB. Rock music has been measured as 115 dB and the pain threshold begins at 125 dB. Yet, recent research with hydrophones has revealed that the womb is a “relatively quiet place” – something comparable to what we experience in our normal environment between 50 and 60 dB (Deliege).  With such a safe sound environment surrounding them, it comes as no surprise that babies react to a sudden loud disruption in their usually quiet home. However music is seldom a sudden jolting noise, and it can be argued that if a fetus shows significant response to a particular song, it is not merely responding to a disruption of its usual surroundings.

Early studies attempting to characterize the effects of music on fetal behavior were not very successful.  For instance, in 1985 researchers played various classical music pieces to fetuses from 30 weeks old via headphones placed on the maternal abdomen.  The researchers then noted that variability in fetal heart rate occurred during the music. However, fetal responses were not uniform, with heart rate increasing for some and decreasing for others.  Later, other researchers speculated that perhaps the fetal responses were mediated by the emotional reaction of the mother while she was hearing the same music (Olds, C).  Nonetheless, a later series of studies that examined learning before birth found a more consistent fetal reaction to sound.  An increase in body movements was elicited by the theme song of a television soap opera in a group of 36–37 week old fetuses whose mothers had watched the program throughout their pregnancies.  However, the babies showed no change in behavior when the theme song was played backwards or when a theme song of a program their mother had not watched during pregnancy was played (Hepper). Taken together, these findings indicate that fetal response to a particular piece of music largely depends on their prior experience with the music.  Such experience dependent responses also clearly show that babies have the ability to recognize and learn sounds they hear in the womb.

Furthermore, both prenates and newborns demonstrate a preference for certain types of musical sounds and rhythms over others.  For instance, the pioneering New Zealand fetologist, William Liley, found that from at least 25 weeks on, an unborn child would jump in rhythm to an orchestral performance. Research conducted in a London maternity hospital found that four to five month fetuses were soothed by Vivaldi and Mozart but disturbed by loud passages of Beethoven, Brahms and various types of rock music (Deliege). New evidence of cognitive development in the prenatal era is presented by researcher William Sallenbach, who made systematic, in-depth observations of his own daughter’s behavior from weeks 32 to 34 inside the uterus. Sallenbach observed that in the last trimester of pregnancy, the prenate’s learning state shows movement from abstraction and generalization to one of increased specificity and differentiation. For instance, during a bonding session using calm music, the prenate was observed moving her hands gently. However, in a special musical arrangement with a modern twist (where dissonant sounds were included) the baby’s reactions were more rhythmic and almost panicking (Sallenbach).  Though such research shows us that babies demonstrate an innate preference for music that is consonant rather than dissonant, mothers still have great autonomy in the selection of music which they would prefer for their precious bundles to hear.  Our ultimate objective, of course should be to create not a musical genius but a person well integrated in his physical, emotional, intellectual and spiritual self.  Because babies prefer musical sounds to dissonant noise, an exposure to a variety of musical types would be the best stimulation a mother could offer to her unborn baby.

In addition, many researchers have noted that babies have a preference for stories, rhymes, and poems first heard in the womb. When the mother reads out loud, the sound is received by her baby in part via bone conduction.  After the sixth month, the fetus can be observed moving in rhythm to the mother’s speech patterns. Even when the baby is born, he/she reacts to familiar rhythms and speech patterns in a positive way – by looking toward the sound, smiling, and showing other evidence of recognition. Such an observation serves as further evidence of babies’ capabilities to retain certain sounds in their memory. Further research seems to indicate that prenates exposed to lullabies inside the uterus can actually be calmed by the music and even lulled to sleep (Hepper).  Surely, a calming effect that reduces hyperactivity and stabilizes heart rate is beneficial to a growing developing baby.

The elements of music – namely tonal pitch, timbre, intensity and rhythm – are also elements used in speaking a language. For this reason, prenatal exposure to music can essentially prepare the ear, body and brain to hear, integrate, and produce language sounds.  Different elements might be effective to achieve this preparation – the first of course being the pure effect of music – but also the combination of a musical experience expressed by the mother’s voice.  A maternal voice is the main sound stimulus throughout the perinatal period, and the voice continues from prenatal to postnatal life.  Thus, a mother’s voice forms a type of sensory “bridge” into postnatal life that is hardly available from other prenatal sensations.  In addition, the mother’s voice has been proven to have an impact on the developing brain.  At birth, newborns react to musical rhythms of speech and thus orient to the social world. It is even hypothesized that this relationship is essentially “musical” because babies do not yet understand the meaning of words. By listening to the mother, the fetus actually learns her musical speech-features (Deliege).  Prenatal exposure to real music (not just the musical elements of human speech) will even further enhance this wonderful innate ability to learn through music.  Music can thus be considered a “pre-linguistic language” which is nourishing and stimulating to the whole human being, sustaining and awakening the qualities in us that are wordless and otherwise inexpressible.

Not only does music heard prenatally stimulate a baby’s inherent learning ability, it can actually enhance his/her future memorization capabilities.  Using Howard Gardner’s famous concept of multiple intelligences (spatial, kinesthetic, interpersonal, intrapersonal, linguistic, logical, and musical) one researcher has presented evidence for musical intelligence before birth.  A 1991 study discovered that prenates exposed to a certain musical piece during pregnancy responded with focused and rapt attention to this music after birth.  On hearing the music after birth, these newborns had a significant decrease in heart rate and movements, and shifted into a more alert state (Hepper).  This ability to react to music heard from past experience in the womb is good evidence of long-term memory being used.  Although more research needs to be conducted in this area, many doctors agree that if used correctly, music can be one of the earliest forms of exercising the brain and long-term memory.

The powerful connection between sound and prenatal memory/learning have been revealed in formal experiments, parental observations, clinical records, and first person reports.  Although some studies disagree as to the extent of influence music has on an unborn child, one thing is certain: sound and music is an important element that can be beneficial to a baby’s development inside the womb.  I know my growing baby can hear, react, and learn from different sounds, so I am always singing, talking, and playing music to my baby.  Undoubtedly, the complexity of hearing and learning is always being discovered by the tiny lives that have yet to take their first breath in our loud and musical world.