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971.
Twenty mother-infant pairs were observed once a week for 7-hour periods when the infants were 2, 3, 4, and 5 weeks old. The occurrence of crying and its relationship to patterning of maternal behaviors was studied in two social contexts: while the mother was holding the infant and while she was not holding the infant. There were significant individual differences in the amount of crying in each of these contexts. The amount of crying in the two contexts was not correlated. Six variables describing forms of maternal attention throughout the 7-hour day were selected, and profiles were formed from measures of these variables. These profiles were found to vary systematically as a function of the amount of crying while the mother was holding the infant. In this context, only physical stimulation increased linearly with increased crying, whereas other forms of attention showed a U-shaped function in relation to increased crying. No relationship was found between crying while the mother was not holding the baby and patterns of interaction. We conclude that the structuring of a mother-infant relationship is reflected in the amount of crying that occurs while mother and infant are in close physical contact. The results also provide evidence that the social context for an infant's crying must be taken into account if the full adaptive value of crying is to be understood.  相似文献   
972.
Examples are given of research on (a) stressful procedures and assessments in the neonatal intensive care nursery and (b) natural caregiving stimulation and self-comforting behaviors that alleviate these stressful experiences. The data from the studies on stressful procedures and assessments revealed that (a) weaning from mechanical ventilation was associated with increased plasma cortisol levels; (b) heelsticks and tube insertions for gavage feedings were accompanied by decreases in oxygen tension (TcPO2); and (c) Brazelton neonatal behavior assessments were followed by increased cortisol levels and decreased growth hormone levels. To alleviate stress, various interventions were tried including caregiver comforting techniques and giving the neonates opportunities to comfort themselves by sucking on pacifiers. The caregiver intervention studies revealed that (a) a simple placement of hands on the head and abdomen of the NICU neonate resulted in a lesser need for oxygen and (b) massaging the NICU neonate resulted in greater weight gain and earlier discharge. In those studies that explored the infant's self-comforting, nonnutritive sucking behavior, the following results emerged: (a) sucking on pacifiers during heelsticks resulted in less crying and lower heart rate and respiration and (b) sucking on pacifiers during tube feedings resulted in smoother bottle feedings later and in greater weight gain. Thus, it appears that several forms of cost-effective interventions can alleviate these stressful procedures and facilitate infant growth and development.  相似文献   
973.
Administration of the Miranda Warnings to deaf suspects poses many legal issues. If police officers, judges, attorneys and psychologists are unaware of these, evidence obtained as a consequence of deaf suspects waiving their Miranda Rights may be inadmissible in court. These issues include the importance of videotaping the police interview, the use of sign language interpreters, the determination of the deaf defendant's reading level and communication capacity, the limitations of lipreading, and other psycholinguistic factors. Recommendations are offered to aid in determining whether a deaf suspect is capable of understanding the Miranda Warnings and how these warnings should be administered.  相似文献   
974.
Forty-four depressed and non-depressed mothers participated in a videotaped interaction with their own infant and then rated the videotape using the Infant Stereotyping Scale and the Interaction Rating Scale. In addition, one half of the mothers rated a videotape of an unfamiliar infant who was labelled psychologically ‘depressed’ and the other half rated a videotape of the same infant with no label given. Both the depressed and non-depressed mothers rated the ‘depressed’ labelled infant more negatively than the non-labelled infant on the attributes of physical potency, cognitive competence, sociability and difficult behaviour. Physical appearance was the only rating that was not biased by the ‘depressed’ label. Mothers' ratings of their own infants were more positive than their ratings of the non-labelled stimulus infant. Depressed mothers did not see their infants more negatively except on one rating. They rated the physical appearance of their own infant more negatively than non-depressed mothers.  相似文献   
975.
This study investigated the sleep/wake states, respiration, and affective behaviors of premature infants who were provided à “breathing” bear in the isolette from 33 to 35 weeks conceptional age (CA). The Breathing Bear is à source of rhythmic stimulation that is optional for the infants. Its “breathing” reflects the breathing rate of the individual infant. At 33 weeks CA, 27 premature infants were provided à Breathing Bear (BrBr) and 26 were given à Non-Breathing Bear (N-BrBr). At 35 weeks, interfeed observations for an average of 1.7 hours were made of the babies' states and state-specific behaviors, along with respiration recordings. By 35 weeks, the BrBr babies showed less wakefulness, more quiet sleep, fewer startles in quiet sleep, and less crying than the N-BrBr babies. In addition, they were more likely to smile and N-BrBr babies were more likely to grimace in active sleep. These findings replicate and extend previous reports of effects of the Breathing Bear on neurobehavioral organization. They also suggest that less negative affect is expressed by the BrBr babies; and they point to the importance of future study of preterm infants' affective expressions, both in sleep and in waking.  相似文献   
976.
Behavioral, physiological (i.e., endocrine), and anatomical consequences of crowding in mice were studied in a situation where animals were in auditory, visual, olfactory, and tactile contact but restrained from full physical interactions, to prevent overt aggression. Males that cohabited with females undisturbed by neighboring conspecifics showed greater propensity to attack same-sex intruders and had higher plasma testosterone levels than did their “crowded” counterparts, that is, males cohabiting with females and housed adjacent to other male/female pairs. In this respect, the latter animals resembled submissive males. However, a significant increase in weight of androgen-dependent target organs (i.e., seminal vesicles and preputial glands) was found in crowded males. These data indicate that despite the observed inhibition of social aggression these males are not physiologically comparable (homologous) to male mice that experienced defeat and the stress of submission during fighting. The intriguing possibility that different conversion pathway of testosterone are accelerated, as a result of social communication, in males living in these two environments and the behavioral implications of these possibilities are discussed. Finally, the parental behavior of crowded animals, although not freely interacting with each other, was disrupted, causing a marked decrease in reproductive success. In this situation a high incidence of infanticide of their offspring by both parents was observed, whereas this behavior was virtually absent in non-crowded male/female pairs.  相似文献   
977.
To determine whether infants of “depressed” mothers interact better with their nondepressed fathers, twenty-six 3- to 6-month-old infants were videotaped during face-to-face interactions with their parents. The “depressed” mother group consisted of twelve 3- to 6-month-old infants and their “depressed” mothers and nondepressed fathers. The control group was composed of 14 nondepressed mothers and nondepressed fathers and their 3- to 6-month-old infants. In the “depressed” mother group, the nondepressed fathers received better interaction ratings than the “depressed” mothers. In turn, the infants received better interaction ratings when they interacted with their nondepressed fathers than with their “depressed” mothers. In contrast, nondepressed fathers and mothers and their infants in the control group did not differ on any of their interaction ratings. These findings suggest that infants' difficult interaction behaviors noted during interactions with their “depressed” mothers may not extend to their nondepressed fathers. The data are discussed with respect to the notion that nondepressed fathers may “buffer” the effects of maternal depression on infant interaction behavior.  相似文献   
978.
The automatic skeletal motor responses of 20 male and 20 female student subjects (aged 20–36) receiving a painful stimulation (electric shock) were studied by examining voluntary concomitant extensions and flexions of the arm. These movements were either of long duration, allowing for an on-line control of their execution or, of short duration, requiring extensive pre-programming. Subjects were instructed either to push or to pull a lever upon receipt of an acoustic signal, which was paired or unpaired with an electric shock. Latencies for long duration movements (regardless of direction) were reduced by reception of painful stimulation. Latencies of short duration extensions and flexions were respectively reduced and increased by painful stimulation. Latencies of short duration movements were larger for females than males, regardless of movement direction. These data suggest that painful stimulation elicits automatic movements which affect programming of the termination of simultaneous voluntary movements. Implications of these findings for the study of aggressive behavior are discussed. © 1994 Wiley-Liss, Inc.  相似文献   
979.
Immature rats are able to give maternal care to pups and may increase their inclusive fitness by helping newborn siblings. Immature males are generally reported to be more maternal than females. In this research we studied sex differences and the extent to which they may be due to a different emotional response to novelty. We studied maternal response in two groups of immature rats of both sexes: in the naive group, juveniles aged from 18 to 30 days were given one test and showed clear-cut sex differences. The experience group was submitted to repeated tests from 18 to 30 days of age, thus eliminating the effects of novelty: as a result, all differences between sexes disappeared. A second experiment was designed in 24-day-old females to differentiate the effects of repeated handling and exposure to the test situation from that of repeated exposure to pups; moreover, the effects of an anxiety-reducing drug (diazepam) were studied. Exposure to pups is particularly efficient in facilitating maternal response. Diazepam injection was also effective, but its control showed that the injection per se was responsible for the effect. In conclusion, our results stress the importance of response to novelty and suggest that sex differences in maternal behavior of immature rats may be modulated by different emotional responses by males and females. In fact, emotionality competes with, and may exert an inhibitory effect on, the expression of a vast array of behaviors. © 1994 Wiley-Liss, Inc.  相似文献   
980.
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