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The development of home orientation was evaluated in 2-14-day-old kittens nursing from mothers fed a protein-restricted or control diet during late gestation and lactation. Although restricted kittens remained in the home when placed in it, their ability to return to the home was delayed when they were removed from it. Restricted kittens also exhibited aberrant locomotor development and an increased frequency of loss of balance (upsets) en route to the home. During postnatal Week 1, vocalization frequency, an index of kitten disturbance when outside the home, was increased in restricted kittens tested in the home, and in adjacent and diagonal corners. Restricted kittens persisted in vocalizing more frequently than controls in home and adjacent corner tests during Week 2. Taken together, these data suggest that maternal protein restriction during late gestation and lactation disrupts the development of home orientation behavior by impairing locomotor function and increasing emotional responsiveness.

Nitrous oxide has acquired widespread use as a tool for managing young dentally anxious children. Clinical impressions have suggested it eliminates uncooperative behavior while alleviating anxiety and facilitating coping skills. Data to support these claims documenting the effects of nitrous oxide across sequential visits has not previously been presented. Research which attempts to clarify the impact of a particular intervention on anxiety reduction, the development of coping skills, or the modification of patient attitudes toward care can anticipate numerous and complex methodological obstacles. Nevertheless, it seems important that longitudinal approaches which examine the anxiety process prospectively are necessary to clarify the immediate and long-term consequences of proposed anxiety management strategies. Further work seems particularly urgent to develop improved methods, in which to assess and measure childhood dental anxiety and the impact of strategies directed at its reduction. Further study which addresses these issues is needed to guide best the effective and appropriate use of nitrous oxide for the pediatric patient.

13 male Long-Evans hooded rats were tested on a CRF-50 reinforcement schedule. Total response time as well as time and total activity responses away from the bar were significantly influenced by injections of methylphenidate (1.2 mg/kg I.P.). In general, the data supported previous findings of reduced response rate to the drug. However, methylphenidate (a CNS stimulant) increased activity that was not related to bar pressing. Analysis of activity response to drug should include total time and activity as well as operant rates.

Avoidance conditioning during pregnancy, changes in caretaker behavior during lactation, and changes in offspring catecholamine levels and behavior were investigated in C57BL/6J mice. Three equal groups of mice were employed. One group was avoidance conditioned prior to pregnancy and continued to avoid shock during pregnancy; a 2nd group was avoidance conditioned during pregnancy; and the 3rd group served as untreated controls. Offspring were crossfostered after birth. During lactation the proportion of time the caretaker spent on the nest was observed. At weaning pups were individually housed. Offspring dopamine concentrations were measured in the corpus striatum at birth and at days 22 and 42 of age. Their performance was evaluated in the open field at Day 42 of age. The results showed that mice receiving avoidance conditioning prior to parturition were more likely to cannibalize their offspring at parturition than were control animals. Furthermore, preparturiently avoidance conditioned mice spent less time on the nest if they reared offspring from biological mothers who had been avoidance conditioned when compared to similarly treated caretakers who reared offspring from untreated control biological mothers. Regardless of postnatal experiences, adult offspring from avoidance conditioned biological mothers had significantly reduced levels of dopamine in tissue from the corpus striatum and were significantly less active in the open field when compared with offspring from control biological mothers. Behavioral results support the findings of others that the prenatal environment plays an important role in shaping the later behavior of offspring. The decrease in dopamine levels suggests that avoidance training as one form of psychosocial stimulation during pregnancy can be disruptive to the development of the dopamine regulatory mechanisms.

At 3 days of age, rats were (i) subjected to a febrile convulsion, or (ii) were handled, or (iii) were not handled. Evaluation at 30 days of age revealed that animals in the first group were heaviest and most resistant to audiogenic seizure stimuli. No differerences were found in maze-learning ability or activity level.

Young dogs were maintained in isolation from other dogs and under varying degrees of exposure to an alien species (mature rabbits). Parametric observations indicate that an interspecific social attachment develops during the initial hours of co-habitation. The later social interaction patterns of the dogs were influenced, but not irrevocably fixed, by the early cross-specific rearing experience.