The proximate causes, survival value, ontogeny, and evolutionary history of human infant crying are examined. Experiments and field observations involving infant distress vocalizations and begging calls in avian, mammalian, and nonhuman primate species are considered, as are ethnographic records of infant care and responses to crying in nonindustrialized societies. It is argued that human infant crying evolved as a primarily acoustic, graded signal, that it is a fairly reliable, if imperfect, indicator of need for parental care and that its primary function is to promote parental caregiving. Selection pressures that may have shaped the evolution of crying and its potential for corruption through dishonesty also are discussed.

This study examined adult characteristics associated with different responses to infant distress. One hundred eighty-eight parents viewed four 20-second segments of videotape in which a 4-weekold infant was either (a) fussing mildly, (b) fussing vigorously, (c) crying, or (d) crying vigorously. Participants rated their emotional reactions and perception of cry characteristics following each segment. Participants then viewed a 4-minute videotape depicting the same infant progressing from calm to vigorous crying, and indicated when they would intervene to pick up the infant. Relatively high levels of empathy and extraversion and low levels of conscientiousness were associated with more sensitive responses to infant distress. Infant-rearing attitudes had a strong impact on response patterns as well, suggesting that education may be an effective means of increasing parental sensitivity.RESUMEN: Este estudio examinó las características adultas asociadas con diferentes respuestas a la angustia infantil. Ciento ochentayocho padres/madres vieron cuatro segmentos de vídeo de 20 segundos, en los cuales un infante de 4 semanas de nacido estaba (1) alborotando suavemente, o (2) alborotando fuertemente, o (3) llorando, o bien (4) llorando fuertemente. Los participantes evaluaron sus reacciones emocionales y sus percepciones de las características del llanto a continuación de cada segmento. Los participantes entonces vieron un vídeo de cuatro minutos que presentaba al mismo infante en forma progresiva desde el estado de calma hasta llegar al llanto fuerte, e indicaron cuándo ellos intervendrían para alzar en brazos al infante. Relativamente, los altos niveles de empatía y extroversión, y los bajos niveles de escrupulosidad, fueron asociados con respuestas más sensibles a la angustia del infante. Las actitudes de crianza de infantes también tuvieron un fuerte impacto en las respuestas de los padres, lo cual sugiere que la educación pudiera ser un medio efectivo de incrementar la sensibilidad de los padres.RÉ SUMÉ : Cette étude a examiné les caractéristiques adultes associées à différentes réactions à la détresse des nourrissons. Cent quatre-vingt huit parents ont visionné quatre segments vidéo de vingt secondes dans lesquels un nourrisson de quatre semaines (1) s'agitait modérément, ou (2)

Emotional tears may be uniquely human and are an effective signal of distress in adults. The present study explored whether tears signal distress in younger criers and whether the effect of tears on observers is similar in magnitude across the life span. Participants rated photographs of crying infants, young children, and adults, with tears digitally removed or added. The effectiveness of tears in conveying sadness and eliciting sympathy was greatest for images of adults, intermediate for images of children, and least potent for images of infants. These findings suggest that the signal value of tears varies with the age of the crier. The results may shed light on the functional significance of crying at different stages of human development.

This study investigated the effectiveness of orally delivered sucrose in calming agitated 2-and 4week-old infants. Sucrose arrested crying and reduced heart rate and gross activity in 2-week-olds but was ineffective in calming 4-week-olds unless accompanied by eye contact. These results were confirmed in a second study in which the experimenter deliberately either held or avoided the infants' gaze. For infants who received sucrose in the absence of eye contact, or water along with eye contact, crying was only modestly reduced, and this effect was not sustained. The emergent necessity of conjoint visual and gustatory stimulation at 4 weeks of age may mark a transition from calming by nonsocial proximate stimulation, such as sweet taste, to calming by specific, distal social interactions. Implications of the findings for the formation of infant-caregiver affectional ties are discussed.Recent studies on the ability of different substances to calm newborn humans and rats and to protect them against pain have revealed the following: (a) Microliter volumes of milk, fat (corn oil), and the sugars sucrose, glucose, and fructose (but not lactose, the milk sugar) arrest crying in infant rats (Blass &

Crying conveys evidence about an infant’s state and neurological health which, when carefully assessed, can provide diagnostic information for parents and clinicians. When crying is inconsolable or judged to be excessive, it can stress parents, disrupt parenting and, in rare cases, place an infant at risk for abuse. Research has revealed physiological and neural responses to crying that may predispose some adults to maltreat infants. Although this work suggests that parental vulnerabilities contribute to insensitive or aggressive reactions, there is a growing recognition that exposure to large doses of crying may be a challenge for all adults. Support programmes that inform parents about infant crying, enhance parenting, and improve parental wellbeing and coping, are under development with promising initial findings.