[Auditory perception and fetal reaction to react to sound stimulation (author's transl)]

The confirmation of techniques used to stimulate the fetus in utero led us to an exhaustive study of spontaneous intra-uterine noises and those modified by different stimuli (while evaluating the diagnosis of fetal distress with flat cardiac rhythm during pregnancy). By the use of elaborate techniques simultaneously we could appreciate the signal and analyse the information obtained and we able to show incontrovertibly that over and above the basal sound that the fetus could hear it could appreciate the mother's voice and other voices, which were perfectly audible to it but lacking in tone because the sharp frequencies were absorbed. The first results of stimulation using calibrated sounds seem to confirm that the fetus does not react to a sound stimulus when it is in a state of fetal distress, but when there is no fetal distress it does react immediately by change in the heart rate, often associated with movements. This technique, incidentally, can be used to show if the fetus can hear well in the uterus in cases of family deafness or of rubella associated with pregnancy.

Related Concept Videos

Hearing01:31

Hearing

When we hear a sound, our nervous system is detecting sound waves—pressure waves of mechanical energy traveling through a medium. The frequency of the wave is perceived as pitch, while the amplitude is perceived as loudness.
Auditory Pathway01:15

Auditory Pathway

Auditory pathways constitute the complex neural circuits responsible for transmitting and interpreting auditory information from the peripheral auditory system to the brain. Sound waves are initially captured by the outer ear, funneled through the ear canal, and reach the tympanic membrane (eardrum). These vibrations are transmitted via the middle ear's ossicles to the inner ear's cochlea.
When viewed cross-sectionally, the cochlea reveals the scala vestibuli and scala tympani flanking the...
Auditory Perception01:17

Auditory Perception

The auditory system is essential for sound perception, utilizing various critical structures. When sound waves enter the outer ear, they travel through the ear canal and cause the eardrum to vibrate. These vibrations are then transmitted to the middle ear, where three tiny bones – the malleus, incus, and stapes – amplify the sound. This amplification is crucial, as it ensures that the sound vibrations are strong enough to be conveyed to the inner ear. These vibrations then reach the cochlea, a...
Perceiving Loudness, Pitch, and Location01:21

Perceiving Loudness, Pitch, and Location

The human brain perceives pitch through two primary mechanisms reflected in place theory and frequency theory. Each mechanism describes how sound waves are interpreted as specific pitches by the brain, offering insights into the intricate processes of auditory perception.
Place theory, or place coding, suggests that different pitches are heard because various sound waves activate specific locations along the cochlea's basilar membrane. The brain determines the pitch of a sound by identifying...
Hearing During Infancy and Toddlerhood01:29

Hearing During Infancy and Toddlerhood

Hearing begins developing before birth. Fetuses respond to sounds in the womb through changes in brain activity, heart rate, and body movements, showing sensitivity to auditory stimulation. After birth, hearing continues to develop rapidly, supporting language learning and environmental awareness.Auditory Acuity and Sound LocalizationAuditory acuity refers to the ability to detect sounds. Newborns are especially responsive to human voices and can detect many speech sounds, although their...
Perceiving Language Sounds and Structure During Infancy01:20

Perceiving Language Sounds and Structure During Infancy

Infants are born with a predisposition to perceive and categorize basic linguistic sounds. Early in development, they can discriminate sounds from many languages and detect differences in rhythm and pattern. This sensitivity may begin before birth. Newborns exposed to two languages prenatally can recognize both, indicating that fetal language exposure influences later auditory discrimination.Recognition of Familiar SoundsBy five months, infants show preferences for familiar auditory stimuli,...