Sally E. Armitage

Bio: Sally E. Armitage is an academic researcher from University of Cambridge. The author has contributed to research in topics: Amniotic sac & Sound (medical instrument). The author has an hindex of 4, co-authored 4 publications receiving 164 citations.

The fetal sound environment of sheep.

Abstract: Hydrophones implanted inside the intact amniotic sac recorded sounds available to fetal lambs. Unlike recordings made from outside the intact amnion in human subjects, sounds produced at levels similar to normal conversation from outside the ewe were picked up without masking by maternal cardiovascular sounds. Noises from inside the mother were intermittent and linked to her activity.

The Sound Environment of the Foetal Sheep

Abstract: The sound environment of the foetal lamb was recorded using a hydrophone implanted a few weeks before term in a small number of pregnant ewes. It was implanted inside the amniotic sac and sutured loosely to the foetal neck, to move with the foetus. Results differ from those reported earlier for the human foetus: sounds from the maternal cardiovascular system were picked up only rarely, at very low frequencies and at sound pressures around, or below, the human auditory threshold. Other sounds from within the mother occurred intermittently and rose to a high sound pressure only at frequencies above about 300 Hz. Sounds from outside the mother were picked up by the implanted hydrophone when the external sound level rose above 65-70 dB SPL, and the attenuation in sound pressure was rarely more than 30 dB and, especially at low frequencies, usually much less. However, attenuation due to the transmission of sound through the body wall and other tissues tended to change from time to time. It is concluded that the foetal lamb's sound environment consists of (1) intermittent low frequency sounds associated largely with the ewe's feeding and digestive processes and (2) sounds such as vocalisations from the flock, human voices and other sounds from outside the mother.

Postnatal Consequences of Prenatal Sound Stimulation in the Sheep

Abstract: Two experiments were carried out to test the hypothesis that prenatal sound stimulation has postnatal effects in sheep. In the first, a group of domesticated ewes was stimulated with an alien sound and their lambs' response to the same sound was compared with that of lambs born to unstimulated mothers. In the second experiment a group of Soay ewes was stimulated with an alien sound and a comparable group stimulated with a series of bleats. Lambs born to these ewes were tested with both sound stimuli. Lambs tested with sound patterns which they had not heard before birth showed more heart rate acceleration during or after stimulation than did lambs tested with sounds which could already have been familiar. This difference was much greater in the response to alien than to species sounds, and it was less consistent on the first than on subsequent trials. There was also a tendency for a marked change in the respiratory pattern, evidenced as a sigh, to occur in response to familiar sound.

Sound stimulation available to the sheep foetus.

Abstract: Work on the uterine sound environment has been carried out by implanting a hydrophone on the neck of the foetus in two pregnant ewes a few weeks before term. Stimulation with sounds of known amplitude and the use of calibrated microphones and a frequency analyser enabled us to assess (1) the amount of attenuation of sounds of different frequency when they had passed through the maternal tissues and amniotic fluid to become available to the foetus, (2) the absolute level of sound entering the amnion from within the mother and (3) the recognizability of external sound such as speech, when recorded from within the uterus. One puzzling feature of the results has been our inability to hear those sounds which are commonly believed to constitute a predominant stimulus for the foetus: those produced by the maternal cardiovascular system.

The discovery of spoken language

Abstract: Surveying the terrain a brief historical perspective on language acquisition research early research on speech perception how speech perception develops in the first year the role of memory and attentional processes in the development of speech perception how attention to sound properties may facilitate learning other elements of linguistic organization relating perception to production wrapping things up. Appendix - methodology used in studies of infant speech perception.

Prenatal maternal speech influences newborns' perception of speech sounds

Abstract: Pregnant women recited a particular speech passage aloud each day during their last 6 weeks of pregnancy. Their newborns were tested with an operant-choice procedure to determine whether the sounds of the recited passage were more reinforcing than the sounds of a novel passage. The previously recited passage was more reinforcing. The reinforcing value of the two passages did not differ for a matched group of control subjects. Thus, third-trimester fetuses experience their mothers' speech sounds and that prenatal auditory experience can influence postnatal auditory preferences.