Investigation of individual differences in newborn infants

The purpose of the study was to investigate the first manifestations of variation in human beings. The objective was to describe differences that first appear and to clarify some of the dimensions and limits which form the background of such variations. Thirty-nine neonates, all of whom, according to medical opinion, were normal, were used as subjects. Each child was observed for eight 30-minute periods while lying in his cot, and two or three times whilst being fed by his mother. These observation periods were spaced throughout the first, third, and fifth days of life and were planned to take account of the infant's age and feeding cycles. All recording was done in code by the same observer. The following analyses were carried out on cotside data and results were as described: Three states of infant behaviour which were named 'sleep’, 'specific activity', and 'mass activity' were differentiated in terms of the amount and type of movements that infants showed, and individuals were compared to see whether consistent dispositions toward either sleep or mass activity could be found. No such consistency was found. Individuals were compared to see whether or not some babies were consistently more active during sleep or mass activity than others. Results of this analysis were ambiguous. Head, facial, body, limb and extremity movements were totalled for each infant each day and results were compared to see whether infants differed in the sequences they showed. Results indicated that there were no established sequences during the first week. Mass activity was analyzed and seven differently structured patterns were found. Most of these became more frequent as the child grew older, and there were some differences in the patterns shown by different babies. Data from feeding observations enabled a comparison to be made between the feeding situations of bottle and breast fed infants. As a result it was found that breast fed infants experience a wider variety of maternal emotions, tend to be less skillfully handled and to show more signs of frustration. There was no significant difference between the two types of feeding group in proneness to sleep or mass activity.Arts, Faculty ofPsychology, Department ofGraduat