Neurobehavioral Syndromes in Cocaine-exposed Newborn Infants

The effects of fetal cocaine exposure on newborn cry characteristics were studied in 80 cocaine-exposed and 80 control infants. The groups were stratified to be similar on maternal demographic characteristics and maternal use of other illegal substances and alcohol during pregnancy. The hypothesis was that excitable cry characteristics were related to the direct effects of cocaine, while depressed cry characteristics were related to the indirect effects of cocaine secondary to low birthweight. Structural equation modeling (EQS) showed direct effects of cocaine on cries with a longer duration, higher fundamental frequency, and a higher and more variable first formant frequency. Indirect effects of cocaine secondary to low birthweight resulted in cries with a longer latency, fewer utterances, lower amplitude, and more dysphonation. Cocaine-exposed infants had a lower birthweight, shorter length, and smaller head circumference than the unexposed controls. Findings were consistent with the notion that 2 neurobehavioral syndromes, excitable and depressed, can be described in cocaine-exposed infants, and that these 2 syndromes are due, respectively, to direct neurotoxic effects and indirect effects secondary to intrauterine growth retardation.     

Crying and infant abuse in rhesus monkeys

This study investigated the relation between crying and infant abuse in group-living rhesus monkeys (Macaca mulatta). The subjects were 10 abusive mothers with their infants and 10 control mother-infant pairs. Abused infants cried more frequently than controls in the first 12 weeks of life, even when cries immediately following abuse were excluded from the analysis. The coos of 5 abused infants differed from those of 5 controls in several acoustic parameters, whereas their screams and geckers were acoustically similar, when recorded in the same context. Abusive mothers were less likely than control mothers to respond positively to the cries of their infants. Although infant cries may increase the probability of abuse being repeated, infant crying per se does not appear to be a major determinant of abuse.     

The Effects of Maternal Alcohol Consumption and Cigarette Smoking during Pregnancy on Acoustic Cry Analysis

During the last trimester of pregnancy, 127 primiparous Irish mothers were interviewed to ascertain their history of alcohol and tobacco use. Confounding effects due to other drugs were not a factor in this sample. Mothers consumed an average of .21 ounces absolute alcohol (AA) per day, with 62% classified as moderate drinkers, 10.6% as heavy drinkers, and 26% as nondrinkers. Neurobehavioral status was measured using acoustic characteristics of the infant's cry, collected on the third day of life. Multiple regression analysis showed that more ounces AA per day was related to more dysphonation and higher first formant, while more cigarette smoking was related to higher pitch, higher second formant, and more variability in the second formant. Analysis of variance comparisons of these 3 alcohol groups demonstrated significant cry effects on infants of heavy drinking mothers.     

Acoustic Characteristics of Naturally Occurring Cries of Infants with "Colic"

Although infantile colic has long been defined by a perceived excessive amount of crying, acoustic attributes of the cry sound may also contribute to perceptions that this early social behavior is excessive or problematic. From an original sample of 76 infants (38 infants referred to physicians for problematic crying, or "colic," and 38 pair-matched comparison infants), 48 infants who produced naturally occurring cry bouts both before and after an evening feeding were studied: 11 infants with Wessel's colic, 15 infants with non-Wessel's colic, and 22 comparison infants. Standard and vociferous cry segments were selected from up to 2 min of tape-recorded crying for spectrum analysis. Vociferous cry segments had a longer duration, a higher fundamental frequency, and a greater percentage of dysphonation than did standard segments. No differences between infant groups were found in cries before feeding. After feeding, infants who were problematic criers, independent of Wessel's criteria, showed a greater percentage of dysphonation in the vociferous cry segment than did comparison infants. This finding resulted from a decrease in dysphonation in the cries of comparison infants after feeding and an increase in those of infants with non-Wessel's colic. The dominant frequency also increased after feeding in the vociferous cries of infants with Wessel's colic, resulting in these infants having higher-pitched cries after feeding than infants in the other 2 groups. Results indicate that infants who are perceived to have problematic crying have objectively different acoustic features in their cry sounds that are particularly aversive, and that complaints about excessive crying cannot be accounted for simply on the basis of reporting bias in overly concerned or emotionally labile parents.     

Adult Perception of Emotion Intensity in Human Infant Cries: Effects of Infant Age and Cry Acoustics

The relation between adult perception of emotion intensity in the cries of 1- and 6-month-old infants and the acoustic characteristics of the cries was examined. In the first study, adults who were inexperienced in child care rated 40 cries on 3 emotion intensity scales: anger, fear, and distress. The cries of 6-month-olds were rated as being significantly more intense. Different acoustic variables accounted for emotion intensity ratings for the 2 infant ages. Peak amplitude and noisiness of the cry predicted adult judgments of intensity ratings of 1-month-olds' cries; a measure of amplitude ratio (in 2 frequency bands) was the best predictor of intensity ratings of 6-month-olds' cries. In the second study, parents of infants rated the same cries on the same scales. They also rated the older infants' cries as being more intense. The 2 adult groups did not differ on their ratings, and a regression equation derived from one adult group predicted the other adult group's rating of the same infant age better than it predicted its own ratings for the other infant age. Infant age, and its associated acoustic features, seems to be a more important determinant of adults' perception of emotion intensity than are such adult characteristics as gender or infant-care experience.     

The effects of within-group and between-group methodologies in the study of perceptions of infant crying

Recent studies have indicated that various infant cry patterns can be reliably distinguished when directly compared with other infant cry patterns. The purpose of this study was to compare the effects of this within-group method of cry presentation (in which listeners are exposed to 2 types of cry patterns) with the effects of a between-group methodology (in which listeners are exposed to only 1 type of infant cry pattern). 4 groups of adult listeners rated the tape-recorded cries of low- and high-risk infants on 4 Likert-type scale items during experimental phases. In phase 1, subjects were exposed to either the cries of low-risk or high-risk infants but not both. In phase 2, subjects were exposed to both low-risk and high-risk infant cries. In phase 3, subjects were exposed to the cries they heard in phase 1. Whereas all scale items differentiated the low- and high-risk infant cries during the within-group analyses of phase 2, all scale items did not differentiate low- and high-risk infant cries during the between-group phase of the experiment. The specific pattern of results indicate that within-group methods of cry presentation accentuate the perceptual distance among cry types and may actually create many reliable differences that would not be found in between-group comparisons.     

Psychophysiological and perceptual responses to infant cries varying in pitch: comparison of adults with low and high scores on the Child Abuse Potential Inventory.

Based on their scores on the Child Abuse Potential (CAP) Inventory, 30 nonparent adults were classified as either having high CAP scores (n = 15) or low CAP scores (n = 15). Subjects' heart rate and skin conductance were assessed as they listened to audio-taped presentations of four "normal" phonated infant cries and four high-pitched, hyperphonated infant cries. Subjects also rated the cries on several perceptual items. Results showed that both groups of subjects found hyperphonated cries more aversive, distressing, urgent, arousing, and sick than phonated cry sounds. Similarly, all listeners' showed higher skin conductance levels (SCL) in response to hyperphonated than phonated cries. SCL became attenuated over time in response to phonated, but not hyperphonated, cries. Adults in the high-CAP group, showed marginally higher heart rates than low-CAP adults following presentation of all infant cry sounds and responded to phonated cries with marginally higher skin conductance levels than low-CAP adults. The responses of high-CAP nonparent adults are similar to those of parents with histories of physically abusive interactions with their infants.     

Infant Crying and Adults'' Anticipated Caregiving Responses: Acoustic and Contextual Influences

These studies assessed adults' latencies to signal that they would respond to infant crying as functions of (1) the degree of infant distress they perceived in the cry, and (2) contextual information relevant to caregiving. In the first study (N = 34), listeners waited longer to respond to cries that they had earlier rated as sounding less distressed than when they heard cries of higher distress. Further, those who had been told that the infant needed sleep waited longer to respond than those without this information. This effect of context information, however, was limited to the latencies; in another study (N = 50), listeners' ratings of distress were not affected. Several acoustic features of the cries correlated with distress ratings and with latencies to signal a caregiving response. Taken together, the results suggest that adults' responses to crying are influenced both by acoustic gradations in the cry itself and by the caregiving context. Ratings of degree of distress manifest in the cry, in other words, may be highly predictive of caregiving behavior but not wholly so. Finally, although certain acoustic variations related to greater perceived distress and speed of response, differences were apparent between infants in the magnitude of these variations. The implication that the general process of cry perception may be calibrated, or fine tuned, to the range of acoustic variation provided by individual infants is discussed.     

Verbal and Behavioral Responsiveness to the Cries of Atypical Infants

A total of 176 subjects (53 male students, 65 female students, and 58 mothers) were exposed to 1 of 6 types of infant cries coming from an adjacent room while their behavioral and affective responses were observed. The cries were the pain cries of 2 normal newborns, 1 infant with maladie du cri du chat, 1 with Down syndrome, 1 asphyxiated infant with brain damage, and one asphyxiated infant without brain damage. Subsequently the subjects rated the overhead cry on a series of affective, attributional, and perceptual dimensions. The results indicated that the 6 cries differentially affected the subjects' affective, self-reported, and behavioral responses, as well as their tendency to report not hearing the cry. In general, the findings suggested that the highest- pitched cries (those of the asphyxiated infants), in comparison to the lowest-pitched cries (those of the normal and Down infants), elicited less optimal responses from the listeners.     

Prenatal Risk and Infant Regulation: Indirect Pathways via Fetal Growth and Maternal Prenatal Stress and Anger

Pathways from maternal tobacco, marijuana, stress, and anger in pregnancy to infant reactivity and regulation (RR) at 9 months of infant age were examined in a low‐income, diverse sample beginning in the first trimester of pregnancy, with fetal growth and postnatal stress/anger as potential mediators, and infant sex as a moderator. Participants were 247 dyads (173 substance‐exposed infants). There were no direct effects of prenatal risk on RR and no moderation by sex. However, there were significant indirect effects on RR via poor fetal growth and higher postnatal anger. The study adds to the sparse literature on joint effects of tobacco and marijuana, and highlights the role of fetal growth and maternal anger as important pathways from prenatal risk to infant RR.     

Newborn pain cries and vagal tone: parallel changes in response to circumcision

Clinical studies have demonstrated that the cries of chronically stressed, medically compromised infants are characteristically higher and more variable in pitch than those of healthy infants. Other studies have indicated that the vagal tone of chronically stressed infants is significantly reduced in comparison to that of normal infants. A neural model of cry production has been proposed which suggests that decreased vagal tone among infants at risk may, in fact, be related to these increases in cry pitch. Using routine, unanesthetized circumcision as a model of stress, we were able to examine the relation between cry acoustics and vagal tone in normal, healthy newborns undergoing an acutely stressful event. Vocalizations, heart, and respiratory waveforms were continuously recorded from 49 (32 experimental; 17 control) 1-2-day-old, full-term infants during preoperative, surgical, and postoperative periods. Vagal tone, as measured by the amplitude of respiratory sinus arrhythmia extracted from heart period data, was significantly reduced during the severe stress of circumcision, and these reductions were paralleled by significant increases in the pitch of the infants' cries. In addition, individual differences in vagal tone measured prior to circumcision surgery were predictive of physiological and acoustic reactivity to subsequent stress. These results emphasize the potential role of vagal control of the autonomic nervous system during stress.     

Cross-cultural differences in maternal perceptions of cries of low- and high-risk infants

The tape-recorded cries of low- and high-risk newborn infants were rated by 150 inner-city Anglo-American, Black-American, and Cuban-American mothers during the hospital lying-in period following childbirth. Half of each cultural group was primiparous and half was multiparous. The mothers rated the cries along 4 perceptual and 6 caregiving response scale items. Reliable differences were found between low- and high-risk infant cries on all perceptual responses with the effects of culture and parental experience affecting the degree of differences. Generally, Anglo-American mothers found the cries more distressing, urgent, arousing, and sick sounding than Black-American mothers, while Cuban-American mothers showed similarities to both Black- and Anglo-American mothers depending on the scale items. The ratings on the caregiving response scale items paralleled cultural differences found on the perception scale items and previous reports of the mother-infant interaction patterns of other Anglo-, Black-, and Cuban-American samples. The results are discussed as being important in developing nonethnocentric views of the functional significance of the behaviors of the infant at risk, yet as providing evidence of the cross-cultural significance of the cry sound of the infant at risk.     

Child abuse potential among mothers of substance-exposed and nonexposed infants and toddlers

OBJECTIVE: The purpose of this longitudinal study was to determine whether there were differences in child abuse potential among mothers who were nonusers, drug users who accepted treatment, and drug users who rejected offers of treatment, over the first 2 years of their children's lives. METHOD: Participants were mothers of 140 infants, classified into Nonuser (n = 48), Treatment (n = 72), or Refuser (n = 20) groups. The Child Abuse Potential (CAP) Inventory [Milner, J. S. 1980. The Child Abuse Potential Inventory: Manual. Webster, NC: Psytec Corporation] was administered when infants were 4, 9, 12, 18, and 24 months. RESULTS: Results of mixed-model analyses of variances showed no group differences on CAP Inventory abuse scale scores. There were significant group differences in lie scale scores on the CAP Inventory, such that lie scale scores for the Nonuser group were significantly higher than lie scale scores for the Treatment group. CONCLUSIONS: Overall, results support the position that low-income women with many risk factors in their lives are at high risk for potential child abuse, but that their drug use status and drug treatment status does not differentiate them from their nonuser peers from a similar social and demographic background.     

On the importance of fundamental frequency and other acoustic features in cry perception and infant development

This study examined acoustic correlates of adults' ratings of infants' cries. Parents and nonparents rated 12 spontaneous cries from young infants on 8 items describing the cries' aversiveness and on 9 semantic differential items. The results indicated that the duration, the amount of dysphonation, and proportion of energy in various frequency bands were highly correlated with adults' ratings. Further, the pattern of correlations between each of the 17 rating scale items and the acoustic attributes was virtually the same, suggesting that the items represented a single underlying dimension of perceived aversiveness. Finally, no differences were found between the results for parents and nonparents. General issues in the study of cry perception are discussed.     

Drug use,the transition from school to work and occupational achievement in the United States

To determine the effects of drug use on entry into the labor force and subsequent socioeconomic achievement, we estimated duration models of the time elapsed since first leaving school to the first fulltime civilian job and jobs held at ages 24–25 and 28–29. The duration models show inconsistent drug effects: women who use illicit drugs other than marijuana delay entry into the labor force while men who use alcohol daily experience a somewhat more rapid entry. Blacks and those with a lower level of educational attainment enter the labor force more slowly than non-blacks and those with higher educational levels. The more important determinants of occupational outcomes at entry and later points in the work career are the human capital variables, i.e. educational attainment and experience. Duration of time since leaving school to first job has a statistically significant and negative impact on earnings, which increases over time for men but not for women. Being black is consistently associated with higher earnings among women. Holding constant other determinants of socioeconomic achievement, such as family background factors, marital status, race, and participation in different activities and roles during high school, effects of drug use among men and women and across earnings and prestige of the job are weak and inconsistent. The only statistically significant effect is the positive impact of marijuana use on males’ earnings at age 29. The findings lead us to conclude that drug use has only minor impact on occupational achievement in early adulthood.     

Acculturation, substance use, and deviant behavior: examining separation and family conflict as mediators

This longitudinal study examined how separation and family conflict mediated the effects of two acculturation variables (English language use and generational status) on substance use (alcohol, tobacco, and marijuana use) and deviant behavior outcomes in a Mexican American high school age sample. Structural equation modeling indicated that separation was a significant mediator of the relationship between acculturation and alcohol use, tobacco use, and deviant behavior. Family conflict mediated the effects of acculturation on marijuana use and deviant behavior. Model comparisons across gender groups suggested that generational status was an influential acculturation measure for females but not males. Additionally, English language use maintained a direct effect on marijuana use among females, whereas this relationship was mediated by separation for males.     

The effects of exposure to violence and victimization across life domains on adolescent substance use

This study uses longitudinal data from the Project on Human Development in Chicago Neighborhoods (PHDCN) to examine the effects of exposure to school violence, community violence, child abuse, and parental intimate partner violence (IPV) on youths’ subsequent alcohol and marijuana use. We also examine the cumulative effects of being exposed to violence across these domains. Longitudinal data were obtained from 1,655 adolescents and their primary caregivers participating in the PHDCN. The effects of adolescents’ exposure to various forms of violence across different life domains were examined relative to adolescents’ frequency of alcohol and marijuana use three years later. Multivariate statistical models were employed to control for a range of child, parent, and family risk factors. Exposure to violence in a one-year period increased the frequency of substance use three years later, though the specific relationships between victimization and use varied for alcohol and marijuana use. Community violence and child abuse, but not school violence or exposure to IPV, were predictive of future marijuana use. None of the independent measures of exposure to violence significantly predicted future alcohol use. Finally, the accumulation of exposure to violence across life domains was detrimental to both future alcohol and marijuana use. The findings support prior research indicating that exposure to multiple forms of violence, across multiple domains of life, negatively impacts adolescent outcomes, including substance use. The findings also suggest that the context in which exposure to violence occurs should be considered in future research, since the more domains in which youth are exposed to violence, the fewer “safe havens” they have available. Finally, a better understanding of the types of violence youth encounter and the contexts in which these experiences occur can help inform intervention efforts aimed at reducing victimization and its negative consequences.     

Child maltreatment and marijuana problems in young adults: Examining the role of motives and emotion dysregulation

It is well established that childhood maltreatment is an important predictor of marijuana use, but few studies have examined the mechanisms underlying this relationship. The current study examines marijuana motives as mediators of the relationship between childhood maltreatment and marijuana use in a sample of young adults. In addition, pathways from childhood maltreatment to emotion dysregulation, coping motives, and marijuana use were explored. Participants were 125 young adults (ages 19–25, 66.9% female) recruited through online community advertising. All participants completed questionnaires assessing childhood maltreatment, emotion dysregulation, marijuana motives, past year and past three-month marijuana use, and marijuana problems. Correlational analyses revealed bivariate relationships between childhood maltreatment, emotion dysregulation, marijuana motives and marijuana problems (rs = .24–.50). Mediation analyses revealed that coping motives mediated the relationship between childhood maltreatment and marijuana problems, and emotion dysregulation was associated with marijuana problems both directly and indirectly via coping motives. The present findings highlight emotion dysregulation and coping motives as important underlying mechanisms in the relationship between childhood maltreatment and marijuana problems.     

Neonatal pain cries: effect of circumcision on acoustic features and perceived urgency

The relation between neonatal cry features elicited by painful circumcision procedures and the perceived urgency of those cries was investigated. Vocalizations were recorded during circumcision of 30 normal newborn males, analyzed by spectrographic methods and validated with computer techniques. The most invasive procedures elicited significantly longer crying bouts; shorter quiet intervals; shorter, more frequent vocalizations; higher peak fundamental frequencies; fewer harmonics; and greater variability of the fundamental. Cries elicited by the most intrusive procedures were judged by adult listeners to be the most urgent, and cries from similarly invasive procedures were judged to be of the same degree of urgency. Cries appeared to be judged along 3 dimensions described by harmonic, temporal, and pitch characteristics. Subjective judgments and objective quantitative data converge to demonstrate that infants' cries are perceived as varying and, objectively, do systematically vary with respect to the intensity of painful stimuli.     

Cognitive Set and Coping Strategy Affect Mothers' Sensitivity to Infant Cries: A Signal Detection Approach

We used Signal Detection methodology to examine how cognitiveset affects mothers' response to an infant cry. We asked whether a cry from a "difficult" versus an "easy" infant would elicit a change in sensitivity or response bias in mother processing of these cries. Thirty-eight mothers of 4- to 6-month-old infants participated in a Signal Detection task in which they were asked whether they could detect differences between a standard cry and 1 to 4 cry variants. Cry variants differed from the standard cry in small, systematic changes in fundamental frequency. The task was conducted in 2 parts; each part constituted a condition wherein mother received a cognitive set manipulation that labeled the identical cry as coming from either a'difficult'or an "easy" infant. An increase in mothers' sensitivity was associated with the "difficult" infant cognitive set. We examined as well how a coping strategy(illusion of control) affected cry signal processing. Mothers who Exhibited high illusory control were least -sensitive in detecting differences between cries. Two information-prcessing, measures response time and heart rate, were also collected and showed that greater sensitivity was associated with more efficient processing of the cry signal.