bluuebunny/crossref_metadata_2025_split huggingface dataset:
Effects of stimulus intensity and stimulus duration during acoustic priming on audiogenic seizures in C57BL/6J mice
Authors: Schreiber Robert A. 
Published: January 2005

AbstractThe effects of stimulus intensity and stimulus duration were examined in C57BL/6J mice not susceptible to audiogenic seizures (AGS) on the 1st exposure to an acoustic stimulus. Two experiments were performed. In the 1st, 16‐day‐old mice were exposed to 108, 112, 120, or 127 dB for 60 sec. Mice were then tested for susceptibility to AGS at varying ages thereafter. Increasing intensity of noise during priming resulted in heightened peak seizure risk, an extended duration of peak seizure risk, and a prolonged time of seizure risk. In the 2nd experiment, mice were exposed for 5, 15, 30, or 60 sec to 127 dB of noise. Five seconds of noise was barely sufficient to induce later susceptibility to AGS. Increasing stimulus duration from 15 to 30 to 60 sec resulted in increasing seizure risk and duration of peak risk period.
Early protein malnutrition in the rat: Behavioral changes during rehabilitation
Authors: Massaro Thomas F. , Levitsky David A. , Barnes Richard H. 
Published: January 2005

AbstractBehavioral development was studied in 2 groups of rats during the postweaning period. Pups were selected from litters nursed by dams fed either a standard protein (25% casein by weight) or a low protein diet (12% casein) during lactation. Two pups from each litter were housed together and fed the control diet throughout rehabilitation Behavioral observations were made by repeated time‐lapse photography at 5‐day intervals. Differences in h ome cage behavior were observed at the onset of rehabilitation in the postnatally malnourished rats. Increased feeding behavior was observed during the 1st week of rehabilitation. Locomotor behavior was depressed during the rehabilitation period in the experimental animals. Climbing activity, however, was significantly greater. Self‐grooming activity was elevated throughout rehabilitation in post‐natally malnourished animals. During the course of rehabilitation, the behavioral differences between the 2 groups gradually disappeared.
Effect of maternal vitamin a excess on S‐100 in neonatal rat cerebellum: A preliminary study
Authors: Vacca Linda , Hutchings Donald E. 
Published: January 2005

AbstractPregnant rats were administered a teratogenic dose of vitamin A excess on Days 17 and 18 of gestation and intubation controls received the vehicle alone. Pups were sacrificed at birth or on postnatal Days 5 or 10; the cerebellum was removed, frozen, and fixed in preparation for immunohistochemical localization of the brain specific protein, S‐100. Vitamin A produced a transient delay in the appearance of S‐100 in the external granular layer which was no longer evident on Days 5 and 10. These findings corroborate autoradiographic evidence that vitamin A temporarily interferes with neurogenesis. However, the early damage results in permanent behavioral deficits in adulthood despite apparent cytochemical repair.
Response to auditory stimuli in 6‐and 9‐week‐old human infants
Authors: Brown James W. , Leavitt Lewis A. , Graham Frances K. 
Published: January 2005

AbstractResponse to 5‐sec, 75‐dB complex sounds was studied in groups of 24 infants each at 6 and 9 weeks of age. Under conditions appropriate for eliciting orienting, no significant cardiac response appeared at 6 weeks, but a significantly decelerative response did appear at 9 weeks. Measurement of noncardiac responses suggested that sucking suppression is also a component of orienting to sound, that the status of eye‐opening is equivocal, and that previously reported eye‐movement responses are probably a component of startle. We concluded that age changes in orienting may occur in young infants, even when state is controlled, and that the probability of orienting varies with the kind of stimuli employed.
Locomotor‐rotational movements in the ontogeny and play of the laboratory rat RATTUS norvegicus
Authors: Pellis Sergio M. , Pellis Vivien C. 
Published: January 2005

AbstractDuring postnatal development, young laboratory rats, Rattus norvegicus, exhibit a variety of locomotor‐rotational movements, that is, runs and jerk‐jumps, in both playful and nonplayful contexts. The frequency of movement types differed between contexts. Some contexts, such as exploration and sleeping, contained spontaneously (i.e., possible eliciting stimuli were not observed) occurring jerk‐jumps which varied with increasing age. In some contexts, such as social play, in which locomotor‐rotational movements were elicited by observed stimuli, the frequency of jerk‐jumps remained similar throughout ontogeny. During social play some locomotor‐rotational movements were found to have immediate functions, such as achieving advantage over the partner during play‐fighting, and as a means of terminating sensory input from the partner at the end of social contact.
The response of young peking duklings to sibling distress calls
Authors: Gaioni Stephen J. , Applebaum Steven , Goldsmith Jane 
Published: January 2005

AbstractPeking ducklings were tested at 1‐2 or 7‐8 days of age for their tendency to inhibit their own distress calling in response to the distress calls of siblings. At both ages the ducklings displayed a significant inhibitory response of the sibling calls, although the response of the older birds was greater. When the younger ducklings were subsequently tested with variety of acoustic stimuli that wee similar to the nonspecific calls, however, they showed the same degree of response specificity; displayed by older ducklings in previous research: in both cases the ducklings more strongly inhibited their vocalizing in response to the sibling calls than to most of these other stimuli. Finally, it was demonstrated that this differential responsiveness to sibling calls was not due merely to differences in pretest exposure to the sibling calls vs these other stimuli. This sensitivity of 1–2‐day‐old ducklings to sibling distress calls is of interest because (1) this age period is of great importance for the formation of social attachments, including sibling bonds, (2) distress calls are known to play an important role in maintaining family cohesion, and (3) it stands in contrast to the common view that young precocial birds do not respond to sibling distress calls.
Alleviation of infantile amnesia in rats by means of a pharmacological contextual state
Authors: Richardson Rick , Riccio David C. , Jonke Theresa 
Published: January 2005

AbstractAlthough a number of studies have demonstrated that the relatively rapid rate of forgetting in young rats (i.e., infantile amnesia) can be alleviated by various reminder treatments, the possibility of enhancing retention by other procedures seems largely unexplored. Given the putative importance of contextual cues as sources of memory retrieval, this experiment examined whether the presence of a distinctive pharmacological state at training and testing could override infantile amnesia. Weanling rats were given pentobarbital or saline prior to Pavlovian fear‐conditioning. When tested 1 week later, subjects in the same‐state drug condition showed better retention than the same‐state saline group. This finding extends previous work on memory recovery in young animals by demonstrating alleviation of infantile amnesia without a re‐exposure to the CS or UCS during the retention interval.
Correlations among measures of playfulness and skillfulness in captive common marmosets (Callithrix jacchus jacchus)
Authors: Chalmers N. R. , Locke‐Haydon J. 
Published: January 2005

AbstractInfant sensorimotor and social skills, playfulness, and nonplayful behaviors were measured in common marmosets from 6 to 22 weeks old. Different measures of skill showed a low concordance, implying that skill is a multiple rather than unitary attribute. Significant correlations were found between the amount of social play infants performed from 11 to 13 weeks of age and their performance at 14 weeks in (1) competitive food tests with their mothers, and in (2) their ability to negotiate an obstacle for a food reward. Significant correlations were also found between these skills and nonplayful behaviors, however comparable analyses at other ages revealed few significant correlations, suggesting that the association between social play and skills is restricted to the age when infants are rapidly becoming independent of their caregivers both for locomotion and food. Age‐specific correlations occurred between changes in levels of skills and both playful and nonplayful behavious. Our results are consistent with the hypothesis that social play promotes the development of skills, but alternative explanations are possible.
Differential rearing experience, gender, and radial maze performance
Authors: Juraska Janice M. , Henderson Constance , Müller Jutta 
Published: January 2005

AbstractSince both differential rearing and gender have been known to affect maze abilities, the present study examines the performance of male and female hooded rats raised from weaning in either a complex environment (EC) or isolated environment (IC) on the 17‐arm radial maze. In two separate replications, EC rats learned the maze more quickly and accurately than IC rats, as assessed by total errors, the number of correct choices to the first error, and the number correct in the first 17 choices. However, EC rats were more likely than IC rats to employ an adjacent‐arm strategy which may have contributed to their superior performance. There were no gender differences or environment by gender interaction effects on any measure of accuracy or adjacent arm strategy in either replication. It appears that the performance of both male and female rats on the 17‐arm radial maze is similarly influenced by the rearing environment.
Contribution of self‐grooming to onset of puberty in male rats
Authors: Moore Celia L. , Rogers Sigrid A. 
Published: January 2005

AbstractSelf‐grooming was observed to increase during the prepubertal period of Long‐Evans rats. Males were significantly more likely than females to engage in genital grooming during this period. To determine whether self‐grooming contributes to the onset of puberty, males were fitted with collars that either prevented or allowed self‐grooming of hindquarters or were left uncollared from 27 to 48 or 55 days of age when autopsied to determine weight of accessory organs. Ventral, dorsal, and lateral prostrates and seminal vesicles were significantly lighter in those rats wearing collars that prevented self‐grooming. It was concluded that self‐grooming, probably of the genitals, contributes to accessory organ growth in males of this species.
Ontogenesis of learning. II. Variation in the rat's reflexive and learned responses to acoustic stimulation
Authors: Hyson Richard L. , Rudy Jerry W. 
Published: January 2005

AbstractThe onotogenesis of the rat's reflexive and simple learned reactions to acoustic stimulation was investigated in five experiments. The pattern of restults suggests that (a)reflexive reactions to tonal stimulation emerge earleir in ontogenesis that the capacity to learn about thses stimuli, and (b)the age at which simple Pavlovian conditioning is first obsrved depedens on the nature of the acoustic conditioned stimulus (CS). Specifically, these data suggest that pups are not capable of simple Pavlovian conditioning to a 2000hyphen;Hz tone (CS) paired with an oral infusion of sucrose (US) until they are 14–15 days old. The same acoustic stimulus will, however, evoke reflexive reactions (startle inspiration) in pups as young as 10–12 days old. Additionally when a different auditory stimulus (an intermittent trains of clicks) serves as the CS, there is evidence of conditioning in pups only 12–13 days old. It is suggested that these age‐related dissociations in the emergence of reflexive and simple learned responses to sound reflect a caudal‐to‐rostral maturational sequence of the components of the ascending auditory system.
Effects of maturation and priming on audiogenic seizure thresholds in mice
Authors: Fuller John L. 
Published: January 2005

AbstractThe rise and fall of audiogenic seizure vulnerability were followed in three lines of mice selected for brain/body weight ratio and in the heterogeneous stock from which they were derived. Over a period of 12 to 24 days, susceptibility increased and then declined. Subjects retested after a 2‐day interval were more susceptible, but this priming effect declined steadily. Differences in seizure threshold varied unsystematically among the lines. No sex differences in susceptibility were found. Mice who seized were heavier on the average than nonseizers of the same age and line. It is proposed that mice with a slower development rate are less susceptible to the stimulus used to evoke seizures. If so, rapid development may tend to lower the threshold of audiogenic seizures in mice.
Development of locomotor activity of rat pups in figure‐eight mazes
Authors: Ruppert Patricia H. , Dean Karen F. , Reiter Lawrence W. 
Published: January 2005

AbstractIn a series of four experiments, social and experiential factors that influence the development of motor activity in rat pups were examined. Motor activity was monitored from postnatal Days 13 to 21 as photocell interruptions in figure‐eight mazes and comparisons were made between (1) pups maintained in a nest box containing a dam and siblings and allowed access to the maze for 23 hr/day, (2) pups tested daily for 1 hr/day vs pups tested only on postnatal Days 15, 18, or 21, (3) pups tested daily for either 5 min, 30 min, or 1 hr/day, and (4) pups tested daily for 30 min/day either singly in a maze, paired with a littermate, or paired with an anesthetized pup of the same age. A monotonic increase in activity was seen for nest‐box testing, minimal developmental change was seen for pups tested on only a single day or for pups tested with an anesthetized pup, whereas all other groups showed an inverted U‐shaped profile of activity which was influenced by the duration of testing and/or the presence of a littermate. These data emphasize the relevance of environmental factors as determinants of preweaning behavior.
Development of maternal behaviors in prepubertal rats at three ages: Age‐characteristic patterns of responses
Authors: Brunelli Susan A. , Shindledecker Richard D. , Hofer Myron A. 
Published: January 2005

AbstractIndividual 18‐, 24‐, or 30‐day‐old male and female Wistar prepubertal rats (juveniles) were continuously exposed to 3–8‐day old pups in order to determine developmental differences in the expression of maternal and other behaviors during the process of sensitization. The results that emerged from this study are as follows: (a) Maternal behaviors are neither consistent nor integrated in their expression prepubertally; (b) exposure to pups facilitates the emergence of some maternal behaviors in juveniles more easily than others, e.g., retrieving and anogenital licking more than ventral crouching or nestbuilding; (c) there are age‐related differences in the expression of different maternal behaviors, e.g., 24‐day‐olds retrieve more than at other ages; (d) in our strain, few, if any, gender differences are apparent in the expression of maternal behaviors prepubertally; (e) juvenile play behaviors (charge, pounce) are related to retrieving behavior in the context of exposure to pups. Overall, the results suggest that maternal behaviors are distinct developmentally and probably involve different mechanisms in prepubertal animals.
Social facilitation of eclosion in the fire ant, Solenopsis invicta
Authors: Lamon Brent , Topoff Howard 
Published: January 2005

AbstractIn colonies of the fire ant, Solenopsis invicta, eclosion is facilitated by adult workers which strip away and consume the pupal cuticle. This stage‐specific social interaction involves chemical stimuli which are present at the onset of eclosion, concurrent with the initiation of gross movements and separation of the pupal cuticle. Fire ant workers retrieved inanimate objects treated with an extract of eclosing pupae and placed them in the colony brood chamber with the appropriate age group where they were tended by several workers. The facilitation of eclosion by adult colony members appears to be an obligatory process in the development of this species; pupae denied the aid of adult workers during eclosion are unable to remove the pupal cuticle and rapidly succumb.
Associative factors and the development of pecking in the ring dove
Authors: Graf Joan S. , Balsam Peter D. , Silver Rae 
Published: January 2005

AbstractIn these studies, descriptive information on the diet and feeding behavior of ring dove squab is considered in the context of an analysis of the mechanisms underlying the development of eating. Experiment I shows that squab begin to peck at grain around Day 13 and both the rate and efficiency of pecking increase through Day 21 when the squab are weaned. Experiment II shows that squab reared without seed in their home cage do not develop normal levels of pecking unless exposure to seed is followed in close temporal proximity by interaction with parents. It is concluded that an association between some aspect of squab's interaction with seed and a parentally provided unconditioned stimulus is sufficient for normal pecking ot develop. The nature of these associations and their contribution to the ontogeny of independent feeding are discussed.
Deficits in response inhibition and attention in rats rendered mentally retarded by early subcortical brain damage
Authors: Thompson Robert , Harmon David , Yu Jen 
Published: January 2005

AbstractYoung rats with lesions to either the globus pallidus, substantia nigra, median raphe, or pontine reticular formation have previously been reported to be deficient in learning a wide variety of laboratory tasks. In the current study, weanling rats subjected to one of these lesions were rested for three weeks, then examined for acquisition and extinction of a water‐motivated straight alley task, and finally tested on luminous flux discriminations of increasing difficulty. All brain‐damaged groups were slower than the controls in extinguishing the alley task and only the median raphe group failed to show an impairment on the discrimination problems. These results and others suggest that the foregoing lesions produce deficits in inhibitory and attentional processes. The possibility is discussed that young rats bearing these lesions might serve as a model for the investigation of the neurobiological and cognitive disturbances underlying certain classes of mental retardation in children.
Effects of unusually early visual stimulation on the development of homing behavior in the rat pup
Authors: Kenny Patricia A. , Turkewitz Gerald 
Published: January 2005

AbstractTwo studies examined the theory that early limitations on sensory functioning contribute to the organization of a structure for perceptual development and intersensory functioning. Rat pups' eyelids were surgically opened on Day 7, following which the development of homing to their nest site was investigated, with each animal alone in its living cage. Control pups increased homing until Day 14, and then decreased. Experimental pups showed no such decline, with the highest rate of homing evident on the last day of testing. The importance of visual cues for this altered development of homing was examined. Visual cues for the home were reduced by removing all shavings during testing, while leaving an odorous substrate in place. Under these conditions, both groups showed the characteristic increase and decline in homing, suggesting that premature eyelid opening results in a modification of the distribution of attention to visual and olfactory characteristics of the nest.
Impoverished rearing conditions increase stress‐induced irritability in mice
Authors: Riittinen M.‐L. , Lindroos F. , Kimanen A. , Pieninkeroinen E. , Pieninkeroinen I. , Sippola J. , Veilahti J. , Bergström M. , Johansson G. 
Published: January 2005

AbstractIrritability was tested in mice reared in four environmental conditions: impoverished (IC), impoverished + overstimulated (ICS), enriched (EC), and enriched + overstimulated (ECS) conditions. The test used was a modified “bottle brush” test. Both overstimulations and individual housing increased irritability interacting positively with each other. Individual housing but not overstimulation decreased avoidance behavior in the mice.
Sex‐related behavior of immature wild mountain gorillas
Authors: Nadler Ronald D. 
Published: January 2005

AbstractSex‐related behavior in immature wild mountain gorillas consisted primarily of gental stimulating episodes in which one animal thrusted against the body of another. Whereas the immature males used the D‐V position predominantly, a single immature female that performed as an actor used the V‐V position exclusively. All episodes of genital stimulating behavior originated in the context of play and most actors were older (and larger) than recipients of such behavior. The data support the findings of earlier research but suggest that genital stimulating behavior among immature gorillas occurs more frequently than previously thought. These results in conjunction with comparable data on pygmy and common chimpanzees and orangutans suggest that genital‐stimulating behavior by immature individuals is a species‐typical phenomenon in the behavioral development of the great apes.
Social interactions among rats housed in grouped and enriched conditions
Authors: Renner Michael J. , Rosenzweig Mark R. 
Published: January 2005

AbstractTwo experiments examine the hypothesis that brain differences found in environmental enrichment are due to differences in social interaction. Both experiments compare enriched versus group housed rats using videotape records of home cage activity, scored with a protocol developed by the authors. Experiment 1 examines social interactions in group and enriched housed rats in the first 30 days postweaning; In Experiment 2 rats were housed in the differential environments from 90 to 120 days of age, an age at which rats have been reported no longer to engage in play; in addition, weights of sections of the brain were obtained at sacrifice and these showed typical patterns of differences among rats from differential environments. Neither experiment revealed any consistent pattern of differences in social interaction, either by chi‐square comparisons of overall profiles of social activity or by discriminant analysis applied to behavioral observations. No evidence was found in support of the hypothesis that play is responsible for the effects of environmental enrichment.
Discrimination between conspecific and allospecific infants by male gerbils and mice before and after experience of their own young
Authors: Elwood Robert W. , Ostermeyer Malcolm C. 
Published: January 2005

AbstractPrior to the birth of their 1st litter, male gerbils generally respond paternally toward both gerbil and mouse pups. Once they have experience of their own pups, however, they continue to respond paternally toward unrelated gerbil pups but kill mouse pups. Male CSI mice, on the other hand, respond paternally to unrelated mouse pups both before and after the birth of their own litter but tend to ignore gerbil pups at these times. These data are discussed with respect to infanticide, onset of paternal care and the narrowing of effective stimuli for eliciting paternal care.