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Data for 331 cri du chat cases, including 34 Danish probands, are reviewed. The incidence nad the prevalence among the mentally retarded population amounted to 1/45,000 and 1.5/1000, respectively. No striking association with prenatal events, parental ages, or birth order could be demonstrated. There was a significant excess of females. Parental translocations were present in slightly more than 10% of the families, while more rare cytogenetic aberrations (mosaicism, rings, and de novo translocations) accounted for less than 10% of all cases. The phenotypically relevant segment has been narrowed down to the midportion of the 5p15 band. Clinical, radiologic, and dermatoglyphic features are summarized and discussed, with special attention to the abnormal cry, which persists in many older probands, and to developmental abnormalities. No obvious correlation could be detected between clinical features and the localization of the deletion. No marker locus has yet been assigned to the short arm of chromosome 5. Treatment and prevention are briefly discussed.

Maximal inspiratory and expiratory airway pressures (PI max and PE max) were measured in 100 healthy infants (51 males, 49 females; age range, 0.06-3.76 years) by occluding the airway with a suitable face mask during a crying effort. Mean values +/- SD for PI max and PE max were 118 +/- 21 cm H2O and 125 +/- 35 cm H2O, respectively. Maximal inspiratory pressure was independent of age, sex, and anthropometrics, while maximal expiratory pressure showed a low but statistically significant positive correlation with body weight (P less than 0.001).

Fourteen infants who were undergoing routine immunization were studied from a multidimensional perspective. The measures used were heart rate, crying, body movement/posturing, and voice spectrographs. There was wide variability between infants on the measures, especially on the cry spectrographs, although facial expression was consistent across infants. The pattern that did emerge was characterized by an initial response: a drop in heart rate, a long, high pitched cry followed by a period of apnea, rigidity of the torso and limbs, and a facial expression of pain. This was followed by a sharp increase in heart rate, lower pitched, but dysphonated cries, less body rigidity, but still facial expression was of pain. Finally, in the second half of the minute's response, heart rate remained elevated, cries were lower pitched, more rhythmic, with a rising-falling pattern, and were mostly phonated, and body posturing returned to normal. Those faces that could be viewed also were returning to the at rest configuration. It was suggested that facial expression may be the most consistent across-infant indicator of pain at this point in time.

The concept of pain in infancy was explored. It was suggested that our every day usage of the term pain be applied to infants. Essentially this suggestion is that we infer that an infant has a subjective experience that is unpleasant when there is evidence of tissue damage and the infant responds with signs of distress, such as crying, increased heart rate, facial expression consistent with distress or other signs. Conceptualizations of adult clinical pain and infant emotions were compared. It was proposed that our concept of infant pain should be multivariate and should include the ecological context in which pain occurs. In section 2 methodological issues were discussed. Ethical concerns for the protection of infant rights were voiced. Numerous opportunities for studying infant pain produced by necessary medical procedures were pointed out. A number of response systems which offer promise in understanding infant pain were reviewed with respect to their proven applicability to infant emotional and cognitive processes or to adult pain processes. This paper attempted to organize information which will be helpful to the researcher interested in infant pain or developmental processes in pain. From the preceding it should be obvious how remarkably little data we have which bears directly on the issue. The close association between the study of pain and the study of emotion has been shown. The study of emotional development, while ahead of the study of developmental aspects of pain, still lags far behind the study of cognitive development. Recently there has been a call for increased study of the development of emotion. The study of the development of pain might well proceed hand in hand. The present state of the field of infant pain is such that almost any data will add to our knowledge base. The complexity of the concept and the wide range of response systems would suggest that multidisciplinary research teams may develop some of the best research efforts. A multidisciplinary approach has been found to be essential in the treatment of chronic pain, for example. A listing of some of the types of professionals who would contribute would include: physicians, nurses, psychologists, biologists (including those trained in neurophysiology, ethology and endocrinology), sociologists and anthropologists. University medical centers seem an ideal environment for conducting such research, given the close proximity of various specialists and an available subject population.

Two studies were conducted to determine the relationship between variability in acoustic features of the infant cry and medical risk factors. In study 1, 3 groups of preterm infants (healthy, sick and CNS pathology) were compared with term infants at 40 weeks gestational age. The cry was analyzed by computer. The coefficient of variability of cry amplitude and the formant features of the cry differed among the groups of preterm infants. In study 2, 3 groups of term infants at low, moderate and high levels of hyperbilirubinemia were compared on the cry measures. More variability in the formant features of the cry was found in infants with higher levels of bilirubin. The correlation between the coefficient of variation in the cry formants and level of bilirubin was statistically significant. These two studies suggest that variability in the acoustic features of the cry relate to the medical status of the infant and may provide a measure of neurophysiological integrity.

We hypothesized that changes in brain-stem auditory evoked responses related to bilirubin would be associated with changes in cry because of the anatomic proximity in the brain stem of cranial nerves 8 (auditory) and 9 to 12 (vagal complex, which controls cry). Brain-stem auditory evoked responses and computerized cry analysis were used to study the concurrent effects of moderate hyperbilirubinemia on auditory function and cry. Fifty term infants were divided equally into two groups on the basis of serum bilirubin concentrations: low (less than 8 mg/dl; 136) mumol/L and moderate (10 to 20 mg/dl, 170 to 342 mumol/L). Forty-three infants had successful tracings of brain-stem auditory evoked responses recorded with a Cadwell model 5200A evoked response unit during two successive trials, and a cry recording of each infant was analyzed by computer. The moderate serum bilirubin group had an increase in percent cry phonation (p less than 0.02) and an increase in the variability of the first formant (p less than 0.04) in comparison with the low serum bilirubin group. Serum bilirubin values correlated positively with brain-stem conduction time (r = 0.36, p less than 0.01), percent phonation (r = 0.42, p less than 0.004), and variability of the first formant (r = 0.39, p less than 0.02). Percent phonation, the voiced component produced by increased neural control, correlated with the interpeak of waves latencies I to III (r = 0.32, p less than 0.03) and brain-stem conduction time (wave I to V) (r = 0.35, p less than 0.01). We conclude that hyperbilirubinemia affects adjoining areas of the brain stem that control hearing and cry production.

To determine if crying alters cerebral hemodynamics and oxidative metabolism in the brain, near infrared spectrophotometry was used to assess relative changes in cerebral blood volume and the oxidation-reduction state of cytochrome aa3. Thirty-six crying episodes were observed, 20 in healthy infants and 16 in infants with respiratory problems. Throughout all crying episodes cerebral blood volume and oxidized cytochrome aa3 demonstrated oscillatory fluctuations every 10 to 20 seconds, with maximum changes during prolonged exhalations. In 86% of episodes baseline blood volume rose and remained elevated during the cry. The relative content of deoxyhemoglobin in cerebral blood also rose, indicating that venous blood is the major contributor to the increase in blood volume. Changes in baseline cytochrome aa3 oxidation varied with the presence of lung disease and with the chronologic age of the infant. Cytochrome reduction with crying occurred significantly more often in infants with respiratory problems than in healthy infants. Cytochrome aa3 became more oxidized in 82% of crying episodes in healthy infants older than 3 days of age, but no change in cytochrome oxidation was usually noted in those younger than 3 days. Thus crying alters cerebral blood volume in all neonates in a pattern consistent with cyclic obstruction to cerebral venous return; it decreases cerebral oxygenation in infants with respiratory problems.

In normal children aged one month to 16 years, the plasma active renin concentration (PARC) was measured with a renin immunoradiometricassay (IRMA) kit, and was compared with plasma renin activity (PRA). The IRMA for renin was found to be independent of the amount of renin substrate and not affected by the dilution of plasma samples, and was therefore proved to be a simple and reliable method. PRA measured in non-diluted plasma samples correlated well with PARC. In the age-related change, PARC in infants was significantly higher than that in older children. In infants, PARC was markedly higher in the crying state than that in the non-crying state. In normal children aged 7 to 11 years, PARC was significantly increased in the upright position compared to the supine position. These findings suggest that a hyperresponse of PARC to acute stress during blood sampling may cause an increase in active renin secretion in infants, and that stimulation by short-term standing may accelerate the activation of inactive renin or the release of active renin.

Studies of arterialized capillary blood gases and acid-base values were performed on 712 normal persons who were between the ages of 29 days and 24 years. The results were divided for clinical use into six groups by age; linear regression lines were constructed for better understanding of the development of blood gas levels and the acid-base balance. The blood pH essentially remained unchanged throughout the study period. The oxygen and carbon dioxide pressures, base excess of extracellular fluid, and buffer base and bicarbonate levels are lower in infants than in children and adults; adult values are reached at approximately 7 to 12 years of age. The probable explanation for the lower values in infants is discussed. The effects of crying on the composition of blood gases are mentioned.

In this preliminary study the authors try a functional analysis of the mother-child dyad's communicative behaviour during the first year of life. They single out in the operant discrimination and in the model those processes which underlie the development of this particular communicative relationship. This analysis if done in the nursing, crying and playing context.

The transcutaneous oxygen partial pressure (PtcO2) was monitored in 50 healthy, normally and spontaneously delivered newborns. Measurements were performed during the first to fourth day of life. The electrode temperature was 44.5 degrees C. The mean PtcO2 level recorded during about 45 min was 9.2 kPa (S.D. 1.4) recorded from the minute-to-minute values. The PtcO2 level normally oscillated to a certain extent and the oscillations were closely related to the breathing pattern of the patient. When the patient fell asleep during measurement, the normal oscillating pattern was replaced by a "silent pattern". During crying, the PtcO2 level showed four main reaction aptterns. A decrease in the PtcO2 level could be observed during breast-feeding. One child, recently fed, vomited a small amount of breast milk after a short period of crying and apparently had a laryngospasm, shown by a sudden drop in the PtcO2 level without any other signs of discomfort. The study shows that PtcO2 (and thus also PaO2) very sensitively reacts to changes in activity. This implies that earlier used methods for determination of PaO2 might give values that are not representative for the steady state as the sampling method per se might influence the recorded PO2 value.

It has been suggested that the cry may reflect the neurophysiologic integrity of the infant and relate to later developmental outcome. In this study, the cry was recorded at term conceptional age in 18 preterm and 13 term infants using a standardized procedure and analyzed by high-speed computer. At 18 months of age, a significant number of infants were correctly classified as scoring high or low on the Bayley Scales of Infant Development based on the mean and variability in the fundamental frequency, variability in the first formant, and the amplitude of the cry. At 5 years of age, a significant number of infants were correctly classified on the McCarthy General Cognitive Index and on the verbal, perceptual-performance, and quantitative subscales based on the variability of the fundamental frequency, variability of the first formant, and amplitude and duration of the cry. Although preliminary, this study supports the potential use of the cry as a noninvasive measure to detect developmental outcome in the infant at risk.

Robustoxin, a polypeptide consisting of a chain of 42 amino acid residues in a known sequence, has been isolated by cation exchange chromatography from the crude venom of the male funnel-web spider (Atrax robustus). Physiological activity or toxicity in the venom fractions was detected by production of fasciculation in mouse phrenic nerve-hemidiaphragm preparations and by lethality in new-born mice. In the present experiments in Macaca fascicularis monkeys anaesthetized with pentobarbitone, robustoxin (5-30 micrograms/kg infused i.v. over 5 min) produced immediate disturbances in respiration (including dyspnoea and apnoea), blood pressure and heart rate followed by severe hypotension (mean systemic blood pressure less than 50 mmHg) or death due to respiratory and circulatory failure within 196 min. Robustoxin also produced lachrymation, salivation, generalized skeletal muscle fasciculation and a parallel increase in body temperature, and increased firing in skeletal motor and autonomic nerves. These effects closely resembled those produced by i.v. infusions over 5 min of 50 micrograms/kg of crude venom from male A. robustus spiders. Crude venom from female A. robustus spiders (500 micrograms/kg i.v. over 5 min) produced some of the effects elicited by robustoxin and crude venom from male spiders, but to a much less marked extent. It was concluded that robustoxin is responsible for the neurotoxic and lethal effects of human envenomation by male A. robustus spiders.

This article reviews the literature concerning infants' vocalizations and their relation to development of language and to diagnosis in studies of pathology. Some researchers believe that pre-speech vocalizations are reflexes, random activities that serve as practice for motor activities. Others believe they are directly related to the development of language. The literature reviewed dealing with the relationship between abnormal cries and pathology suggest a differential diagnosis of certain pathologies. Crying should be included in the collected symptoms to achieve a more accurate and comprehensive diagnosis.

The different types of crying which can be observed in the healthy and in the sick infant are described. Recent findings on behavioral and electrophysiological research are reviewed which led to a better understanding of the characteristics and possible causes of the different crying behaviors as well as of the effectiveness of therapeutical interventions.