Development of newborn monkeys was assessed by 2 techniques. The 1st was a film analysis measuring aspects of walking, climbing, and jumping in mother-reared infants. The 2nd used a "Baby-Spin" apparatus consisting of a cloth covered bag which rotated in the vertical plane through 360°, 2 sec spins. Mother-reared monkeys walked and climbed on Week 1 but did not jump until Week 3. The duration of arm and leg movements was constant, but because distance of movements changed the speed of limb movement increased over Weeks 1-5. Chsping and grasping responses were in synchrony from the first week of life. Clasping pressure to initial acceleration increased over the first 3 weeks, with greatest pressures at headdown angles on Weeks 1 and 2, and a double-peaked function, appearing on Weeks 3 and 4 with pressure maxima at both headdown and head-up angles. Developmental changes in clasping could be seen in longitudinal or cross-sectional comparisons, or in comparisons confounded by effects of prior test experience.The clasping and grasping reflexes are primary responses keeping neonate macaque monkeys in close body contact with their mothers. Harlow (1960) proposed that these reflexes provide one major basis for social attachment development, a principal event in the primate infant-mother affectional system. Experiments on rhesus monkeys by Mowbray and Cadell (1962) and by Milbrath (1968) suggest that a strong "involuntary" stage of clasp-grasp behavior is present on Days 1-10 of life, and persists through at least Day 14. After this time clasp-grasp responding appears to be largely "voluntary." Other important neonate behaviors include orienting reactions to visual and auditory stimuli, which develop rapidly from 6-1 1 days; the "release and righting" response, which is fully mature in most rhesus neonates by Day 17; and the response of rigid extension of the extremities when dropped or falling, which disappears in most individuals by Day 17.Previous work on reflex behavior of macaque neonates has used methods involving largely uncontrolled and/or unscaled stimulus situations, physical manipulation of the subject by the experimenter during tests, and rating scale measures of response

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ExtractSleep behavior and bioelectric brain development have been studied by means of polygraphic recordings (respiration, eye movements, muscle activity, and electroencephalogram (EEG)) in 22 infants and young children with phenylketonuria (PKU). The EEGs were analyzed by a special visual pattern recognition program as well as by means of computer spectral analysis. The distribution between rapid eye movement (REM) or active and non-REM (NREM) or quiet sleep was not found to be different from control infants of the same age. Quite contrary to current theories on the biochemical regulation of sleep as derived from acute animal experiments, our results indicate that, under chronic conditions, a normal sequence of quiet and active sleep can be maintained despite a severe lack of blood and cerebrospinal fluid serotonin as it occurs in hyperphenylalaninemia. In the EEG of subjects with PKU the development of a rhythm or sleep spindle (12-16 cps) activity was enhanced and already abnormal as early as 5 weeks after term birth. The frequency of a waves as well as of hypnagogic, monomorphic, 6 activity was shifted toward higher values. Dietary treatment of 4-6 weeks duration and normalization of blood phenylalanine levels did not significantly change the abnormal bioelectric phenomena. SpeculationThe increase in high frequency regular rhythmic activity in the sleep EEG of subjects with PKU can be explained by decreased concentrations of inhibitory synaptic transmitters such as serotonin and 7-aminobutyric acid. The developmental course in the expressivity of sleep spindles during the 1 st year of life, together with reliable methods of quantified EEG analysis, seems to be a rather sensitive indicator of normal or abnormal brain maturation. Introductionshould be, in theory, alterations of sleep behavior be-

To determine if a rank order (RO) would be established among a group of 5 female squirrel monkeys, 14 behaviors were observed and performance in water dominance tests was recorded. Significant positive RO correlations were found between active contact and chasing, and between urine-washing and closed genital display. Significant negative RO correlations were found between active contact and huddling, and between chasing and huddling. The RO determined from the results of the water dominance tests was unstable. It was concluded that the communication system in a subadult female squirrel monkey colony could not be described in terms of a linear RO.

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