Learning in mature mice (Peromyscus leucopus) subjected to deep hypothermia as neonates

In certain species of nonhibernating rodents, although young nestlings cease breathing and heart action when their body temperature is lowered to near freezing, the nestlings need only be rewarmed to recover. This remarkable capacity for immediate recovery has been known many years, but long-range consequences of deep neonatal hypothermia have never before been investigated. Mice (Peromyscus leucopus) that had been exposed to four 2.5-hr episodes of deep (2-4 degrees C) hypothermia when 4-10 days old were later compared with littermate controls in their performance on two learning tasks. The two groups did not differ in their acquisition or extinction of a lithium-induced learned taste aversion to sucrose. Nor did they differ in learning to find a hidden platform in a swimming pool. Thus in a nonhibernating rodent species, deep hypothermia experienced neonatally--unlike similar hypothermia administered in adulthood--seems not to induce deficits in subsequent learning capabilities. The resistance of neonates to damage probably represents an adaptation, for their modest thermoregulatory abilities render them vulnerable to deep hypothermia in frigid environments.     

Neonatal responsiveness as a function of maternal contact and obstetrical drugs

This work was designed to study changes in neonatal behavior during the first two days of life. Infants in Part I were from middle-class backgrounds. Half of these infants had unrestricted maternal contact during the first two days of life, the other half had contact with their mothers only at feeding time. Infants in Part II were from low socio-economic backgrounds. They were cared for entirely by the nursery staff during the first two days of life, so that differences in maternal style did not affect their behavior. Half of these babies were born to mothers who received 50 mg meperidine during labor, half to mothers who received no meperidine. This work provided evidence for the sensitivity of the neonate during the first two days of life. Both those infants who received unrestricted maternal contact and those whose mothers had received no obstetrical drugs exhibited more behavioral change than those who received low maternal contact or whose mothers had received meperidine during labor. High maternal contact and absence of obstetrical drugs also resulted in increased sensitivity to some environmental stimuli.     

Modeling a tactile sensory register

A detailed analysis was made of the data of a previous paper by Bliss et al (1966). That paper describes a series of experiments, in which 2 to 12 simultaneous air-jet stimuli were presented on the 24 phalanges of both hands. In addition, new data from an early blind S, whose performance was significantly better, is compared to the data of the original four Ss. Memory properties of all five Ss estimated by whole- and partial-reporting techniques gave evidence for a tactile short-term memory that (1) has a duration of a few seconds, (2) varies considerably in size (but not in temporal characteristics) for different Ss, and (3) has a capacity limited by spatial resolution. Tactile masking did not account for the limited spatial resolution, but a stimulus-spreading (or lateral-excitation) model did.     

Comparisons of stimulus learning and response learning in a punishment situation

These experiments use a procedure in which a rat is trained to make two topographically distinct responses on a single manipulandum, and then one of the responses is punished. Differential suppression of the punished response is taken as evidence of response learning, whereas the common suppression of both responses is attributed to stimulus learning or to general and nonassociative factors. Thus, this procedure begins the experimental separation of animals learning about the consequences of their behavior and animals learning what happens in a particular environment. A further separation is effected by using two such manipulanda; this procedure begins to distinguish between stimulus learning about the manipulandum and the more gereral factors that cause suppression. Some parameters affecting the relative importance of stimulus learning and response learning are examined.     

Role relevant sex typing and opportunity in agentic and communal domains1

The hypothesis associating psychological androgyny with greater personal adjustment has recently been contradicted in several studies in which masculine individuals, regardless of gender, generally appeared to be better adjusted than either androgynous or feminine persons. In the present research, five studies involving 363 subjects tested the hypothesis that such data may reflect a culture that values and differentially rewards agentic (masculine) characteristics and competencies in both men and women while taking communal (feminine) characteristics somewhat for granted. Subjects evaluating candidates for agentic roles preferred masculine candidates (regardless of gender). Masculine and androgynous persons were preferred for a communal role, while feminine persons were almost never chosen for either agentic or communal roles.     

Nonconscious acquisition of information.

The authors review and summarize evidence for the process of acquisition of information outside of conscious awareness (covariations, nonconscious indirect and interactive inferences, self-perpetuation of procedural knowledge). Data indicate that as compared with consciously controlled cognition, the nonconscious information-acquisition processes are not only much faster but are also structurally more sophisticated, in that they are capable of efficient processing of multidimensional and interactive relations between variables. Those mechanisms of nonconscious acquisition of information provide a major channel for the development of procedural knowledge that is indispensable for such important aspects of cognitive functioning as encoding and interpretation of stimuli and the triggering of emotional reactions.     

A theological perspective on social exchange theory

This article provides a brief review of the basic principles of social exchange theory with an emphasis on a social exchange model of conflict. The key concepts of justice, reciprocity, and equity comprised in social exchange theory are addressed from a social and theological perspective.     

At-risk children in Christian families concerning alcohol use

Health educators proposing alcohol prevention programs for a church setting face a variety of problems. Information only preventive types of alcohol programs are being increasingly criticized. The purpose of this study was to identify variables that best predict use of alcohol for children in fundamentalist Protestant Christian families. Three hundred and two students currently enrolled in a mandatory health course at a fundamentalist Protestant Christian university responded to a questionnaire designed to identify contextual or environmental risk factors for alcohol use. A significant difference was found in five of 15 established environmental factors. This paper suggests that an alcohol education program that focused on these differences would be advantageous for the health educator to carry out in the church setting.     

Visual experience, visual field size, and the development of nonvisual sensitivity to the spatial structure of outdoor neighborhoods explored by walking.

When places are explored without vision, observers go from temporally sequenced, circuitous inputs available along walks to knowledge of spatial structure (i.e., straight-line distances and directions characterizing the simultaneous arrangement of the objects passed along the way). Studies show that a life history of vision helps develop nonvisual sensitivity, but they are unspecific on the formative experiences or the underlying processes. This study compared judgments of straight-line distances and directions among landmarks in a familiar area of town by partially sighted persons who varied in types and ages of visual impairment. Those with early childhood loss of broad-field vision and those blind from birth performed significantly worse than those with early or late acuity loss and those with late field loss. Broad-field visual experience facilitates perceptual development by providing a basis for proprioceptive and efferent information from locomotion against distances and directions relative to the surrounding environment. Differences in the perception of walking, in turn, cause the observed differences in sensitivity to spatial structure.     

Effect of time of day on the relationship between mood state, anaerobic power, and capacity

Mood state was estimated in six men using the Profile of Mood States questionnaire, with a "right now" directional set prior to performance of a modified Wingate power test, once at 03.00 hr., 09.00 hr., 15.00 hr., and 21.00 hr., on different days. Anaerobic power was measured as peak power output in 5 sec., and anaerobic capacity was measured as total external work performed during the 30-sec. test. Intraindividual difference scores were calculated as a subject's score minus his mean over the four tests. Multiple regression analyses showed that time of day and the Profile of Mood States fatigue score accounted for 51% of the variance in peak power and 62% of the variance in anaerobic capacity. However, the relationships between fatigue and subsequent anaerobic power and capacity reached statistical significance only at 21.00 hr. These results suggest that intraindividual differences in the mood state are related to subsequent performance. Greater than usual levels of fatigue are associated with reduced performance capacity. However, this relationship is dynamic and is dependent upon the time of day.