Katarina Michelsson

Crying in separated and non‐separated newborns: sound spectrographic analysis

During the first 1‐2 h after birth crying occurs during separation from the mother and stops on reunion. In rats, such “separation distress calls” have distinct phonetic properties. We examined this early crying by sound spectrography in 29 healthy, full‐term, vaginally delivered babies, randomly assigned either to be kept in a cot or to be placed in body contact with the mother during the 90 min following birth. The former babies cried almost 10 times more than the latter ones. The duration of the cry signal (the smallest element of a cry analysed by spectrography) in both groups was 0.8‐0.9s; the melody contour was flat or slightly rising‐falling with a fundamental frequency of around 500 hertz. The cry is provisionally characterized as a discomfort cry, elicited mainly by separation from the mother.

Twenty-Five Years of Scandinavian Cry Research

The study of crying can be dealt with from many different perspectives: anatomical, physiological, psychological, phonetic, and pediatric. During the last two decades, the cry has also been an important factor in studies of mother-child interaction.

Phonation in the newborn, infant cry

Sound spectrographic studies have shown that the crying of newborn infants has a fundamental frequency of about 400-600 cycles per second, and mostly a slightly rising-falling melody contour. In sick infants, and especially those with diseases affecting the central nervous system, abnormal cry characteristics occur. The fundamental frequency has been increased, and the melody contour is unstable. Various cry characteristics, which rarely occur in cries of healthy infants, are more often present in cries of the sick ones. Studies of cries in newborn infants have been especially aimed to determine whether cry analysis could be successful in diagnostics and in the early detection of the infant at risk for developmental difficulties.

Sound Spectrographic Cry Analysis of Infants with Bacterial Meningitis

A total of 110 pain‐induced cries from 14 infants with bacterial meningitis were analysed by sound spectrographic methods. The infants were between four days and six months old, and the cries were analysed between one and 14 days after the diagnosis. The cry analysis was compared with the crying of 75 full‐term healthy infants. 15 cry attributes were studied.

Pain cry in full-term asphyxiated newborn infants correlated with late findings.

Abstract. 115 pain‐induced cries from 45 full‐term newborn infants with pre‐ and perinatal asphyxia were analyzed by sound spectrographic methods. All the infants had signs of intrauterine asphyxia and Apgar score of 6 or less at 5 min. The mean birth weight was 3170 g. The pain cries were recorded before the age of 8 days, 83 % of the cries before 3 days of age. The cry analysis was compared with the pain cries of 75 full‐term, healthy newborn infants of corresponding birth weight and gestational age. The results showed significant differences between the cries of the asphyxiated newborn and the healthy infants. The duration of the phonation was shorter, the maximum and minimum pitch of the fundamental frequency was significantly higher. Bi‐phonation and vibrato occurred more often, double harmonic break and glottal roll less often. An increase in rising, falling‐rising and flat types of melody was observed. Retrospectively, the cries were more abnormal if the infant was found to be neurologically damaged at the check‐up at 2–8 years.

Nine‐year Follow‐up of Infants Weighing 1 500 g or Less at Birth

ABSTRACT. A nine‐year follow‐up of 116 children born consecutively in 1971‐74 with a birthweight of 1500 g or less showed that 59 had died. Of those who were alive, four had severe motor and/or mental handicaps and three were blind because of retrolental fibroplasia. The low birthweight children without severe handicaps were found to have impaired motor function, speech defects and impaired school achievement more often than the controls. There was a significant correlation between the test results at the age of five and nine years, which indicates that children with school failure can be recognized and early remedial treatment started before school or on starting school.

Sound spectrographic analysis of pain cry in preterm infants

Sound spectrographic cry analysis was performed on 302 cries of 48 preterm infants born at 30-37 gestational weeks. The cries were recorded during the first week of life and thereafter weekly until the infants were discharged. The control series comprised 54 cries from 27 fullterm healthy infants. The results showed that the cries of the smallest prematures compared with the controls were shorter, more high-pitched, and included bi-phonation and glide more often. The cry characteristics changed with increasing conceptual age and the older the child the more the cry pattern resembled that of the fullterm. The cries of the preterm infants when they had reached 38 conceptual weeks were similar to those of newly born fullterm infants. The results indicate that the gestational age should be taken into consideration in cry analysis.

Neonatal risk factors and later neurodevelopmental disturbances.

Background factors of developmental outcome in a group of 386 neonatal ‘at‐risk’ infants and 107 controls were examined in a prospective nine‐year follow‐up study. Dichotomized outcome variables were computed for each of the assessments; neurodevelopmental, motor, psycholinguistic, cognitive and school progress. In the study group, 17 to 29 per cent were found to have significant problems, compared with 10 to 17 per cent of the control group. Children with low birthweight, neonatal neurological symptoms or several neonatal disorders were found to have most problems at the age of nine years. In stepwise logistic regression analyses, smallness for gestational age, neonatal signs of cerebral depression and low social‐class were found to be the most significant predictors of neurodevelopmental problems at age nine. Factors suggesting intra‐uterine hypoxia or poor nutrition were also associated with developmental problems. The background pathology of the neonatal conditions seemed to be of more importance than the neonatal manifestations themselves.

Newborn infants' cry after heel-prick: analysis with sound spectrogram

The aim of the study was to test the hypothesis that a newborn infants cry can be used in conjunction with an instrument to measure pain. Crying due to pain was analysed after a heel‐prick stimulus. In a prospective, descriptive study, 50 healthy newborn infants were subjected to a heel‐prick for phenylketonuria screening. Their cries of pain were recorded and analysed. Duration of the crying sound was analysed and, using a sound spectrogram, the fundamental frequency and the cry melody of the first five cry sounds were analysed. The analysis showed that the crying sound after the painful stimulus of the heel‐prick had a significantly higher fundamental frequency and lasted longer at the first than at the fifth cry. The first cry had a more varied crying melody than the fifth. There were large differences between individual cries from a single infant, as well as in the duration of each cry, total crying time, and fundamental frequencies between infants. While the first cry was more like a cry of pain, the fifth cry more resembled crying for reasons other than pain. The results suggest that newborn infants react to pain in a recognizable way. However, other stimuli may cause a similar reaction. Crying can therefore be used to measure pain in newborn infants only when the cause of crying is known.

Neurodevelopmental Screening at Five Years of Children Who Were At Risk Neonatally

A neurodevelopmental screening test with cumulative scoring for abnormal test responses was performed on 845 five‐year‐old Finnish children who, in the newborn period, had had disorders which placed them in à high‐risk group, and on 70 controls. The results showed à significant difference between the neurodevelopmental scores of the risk‐group children and those of the controls. The scores were higher if the child had had many of the risk factors simultaneously. Boys had significantly higher scores than girls. The mean scores also varied between different risk factors. It is evident that slight neurodevelopmental deviations at the âge of five years can derive from disorders in the newborn period.