Biological vs experiential factors in phobic conditioning

The present study was performed as a test of phobic conditioning being a case of prepared learning (Seligman, 1971). Skin conductance responses were conditioned in three groups of subjects to either slides of snakes and spiders; electric outlets; or geometric shapes, as conditioned stimuli (CSs) with shock to the forearm as the unconditioned stimulus (UCS). The purpose of the experiment was to compare electrodermal conditioning to potentially phobic CSs, i.e. snakes and spiders, with conditioning to fear-relevant, but non-phobic, CSs, i.e. electric outlets.Each subject saw two pictures, either a snake or a spider; or two different slides of electric outlets; or two different geometric shapes. Only one of the two cues (the CS + ) was immediately followed by the shock-UCS during the acquisition phase. Thus, a differential paradigm was used. There were 4 habituation, 12 acquisition, and 16 extinction trials. The duration of the pictures was 8 sec with an intertrial interval of between 35–45 sec.The results showed reliable effects of conditioning in all three groups during the acquisition phase. Furthermore, a significant interaction during extinction is reported, indicating responses to potentially phobic CSs to be more resistant to extinction than responses to the other two classes of stimuli. It is concluded that the present results favor an interpretation of phobic conditioning in terms of biologically prepared learning.     

Effects of morphine hydrochloride on social encounters between male mice

The effects of a single injection of morphine hydrochloride (0.3, 0.6, or 1.25 mg/kg) or physiological saline (0.9% NaCI) on the agonistic behaviour elicited by isolation in male mice were examined. Individually housed mice were exposed to anosmic “standard opponents” 30 minutes after drug administration, and the encounters were videotaped and evaluated using an ethologically based analysis. Morphine (at 0.6 and 1.25 mg/kg) significantly and dose-dependently decreased time spent in offensive (“threat” and “attack”) and “digging” behaviours but markedly increased “non-social exploration” without a significant increase of “immobility.” The lowest dose was completely ineffective in producing changes in any of the behaviours studied. It is concluded that these results present a specific ethopharmacological profile characterized by suppression of aggressive behaviour, increase in non-social explotation, and no evident impairment of motor activity. © 1993 Wiley-Liss, Inc.     

Gender-specific social experiences and the development of aggressive and sexual behavior in male mice

This study examined influences of gender-specific social experiences on the development of aggressive and sexual behavior in male mice. To determine the effects of gender-specific social experience three different types of groups were constituted after the animals had been weaned. The subjects were randomly assigned to different treatments. Female groups were composed of one experimental male and three female cohabitants. Male groups were composed of five experimental males each, and the mixed-sex groups were composed of two experimental males and of two females. The experimental subjects stayed in these groups until the age of approximately three months, when the testing for sexual and aggressive behavior commenced. For the sexuality tests, a receptive female was placed in the home cage of the experimental male for ten minutes. A nonaggressive male was placed in the home cage of the experimental male for seven minutes for the aggression tests. The experimental males were administered both sexuality and aggression tests, the sequence of testing sexual and aggressive behavior was systematically varied in order to control the influence of the two different types of behavioral tests. The results showed that males with only male social experiences showed fewer responses and were less active in both the aggression and sexuality tests than the males from the two other types of groups. Significant positive correlations between activity during aggression and sexual tests were obtained for all three groups. © 1994 Wiley-Liss, Inc.     

Economic deprivation,experiential deprivation and social loneliness in unemployed and employed youth

One hundred and forty‐eight youth were allocated to one of four occupational sub‐groups: 47 unemployed with no access to paid work; 32 unemployed with access to some paid work; 30 unemployed with access to regular paid work; and 39 full‐time employed. All participants were assessed for levels of Economic Deprivation, Experiential Deprivation, Social Loneliness and Psychological Distress. Results indicated that Economic Deprivation and Experiential Deprivation varied according to occupational status, with those full‐time employed having the least deprivation and those not attached to the work‐force experiencing the most. Levels of deprivation were related to levels of Psychological Distress. Social Loneliness also varied across the occupational groupings. The unemployed with access to regular paid work experienced the least Social Loneliness; the unemployed with no paid work experienced the most. Lastly, both Economic and Experiential Deprivation were able to predict Psychological Distress; only Experiential Deprivation was able to predict Social Loneliness. Results are discussed in the context of Jahoda's ( 1982 ) deprivation model and Weiss's ( 1973 , 1974 ) social loneliness model. Copyright © 2001 John Wiley & Sons, Ltd.     

Genetic basis for male aggression and survivorship in wild house mice (Mus domesticus)

Work on the genetic region of the house mice known as the t-complex has produced the hypothesis that mice heterozygous for t-haplotypes (+/t) may have a selective advantage over wild-type (+/+) males owing to the greater aggressiveness of +/t males. We tested this hypothesis by examining the behavior of +/+ and +/t mice placed in four large outdoor enclosures. We found that +/t males were dominant over +/+ males. Furthermore, in the outdoor enclosures +/t males had higher survivorship than +/+ males, both as adults and juveniles. However, males of the two genotypes did not differ in home range size. We suggest that t-haplotypes may be, in part, maintained in mouse populations because of a selective advantage in heterozygous males. © 1996 Wiley-Liss, Inc.     

Structural and experiential factors in newborns’ preference for speech sounds

It is well established that newborns prefer some sounds over others. It is widely believed that these preferences reflect past experience, either prenatally or in the immediate postnatal environment. However, it is also possible that structural factors are involved. The frequency of occurrence of different sounds in the languages of the world may provide evidence of such structural factors. If structural factors are important, and if frequency of occurrence of sounds in the world’s languages reflects structural factors, then we might expect newborn preference for sounds to reflect their frequency across languages. In this study, newborns were presented with two cv pairs consisting of a trilled /r/ and a bunched /r/ followed by the vowel //. The newborns were either of English‐speaking or Spanish‐speaking origin. The bunched /r/ occurs in American English and is not frequent in the languages of the world. It does not occur in Spanish. The trilled /r/ occurs in Spanish and is a frequent consonant in the languages of the world. It does not occur in American English. Results showed that newborns of both linguistic backgrounds preferred to listen to the trilled /r/. It is hypothesized that the frequency of occurrence of a sound in the languages of the world may reflect structurally based ease of production and ease of perception, the latter leading to the newborn preference.     

Effects of male social status on reproductive success and on behavior in mice (Mus musculus)

Differences in reproduction as well as in behavior in the presence of females were evaluated according to dominant and subordinate male rank in albino mice, in the temporary absence of each male's antagonist. Dominant males reproduced more successfully than subordinate males. Subordinate males were generally inactive, except for displacement activities, during the first 15 min they were exposed to female partners. These findings suggest that mechanisms other than male-male interference or mating order may be operating or influencing behavior and reproductive results.     

Genetic and experiential influences on behavior: Twins reunited at seventy-eight years

Twins living in different countries offer opportunities to explore associations between observed differences and experiential effects. This report compared the life histories, cognitive abilities, personality traits, psychomotor skills, medical characteristics, job satisfaction, social support and social relations of dizygotic (DZ) female twins reunited at 78, the world’s longest separated set. The twins’ advanced age also enabled a study of how co-twin differences in aging may be associated with current behavioral and social differences. Consistent with previous studies, these dizygotic reared apart (DZA) twins showed discordance across some, but not all, traits. Their different rearing situations and life histories may explain current differences in their responses to meeting their twin. This case highlights the importance of both genetic and rearing factors on behavior, but does not allow firm conclusions regarding the extent to which these sources explain individual developmental differences. However, such data contribute to the growing number of cross-culturally separated twins, generating novel hypotheses that may be assessed using larger samples.     

Effects of social stress on tumor development in dominant male mice with diverse behavioral activity profiles

We examined the influence of individual psychological profile and social behavior on tumor development in dominant male mice. Male OF1 mice were subjected to an open field test (OFT) to observe their motor activity and latency. Subsequently, the animals were divided into three groups: Stress-Non-Inoculated (SNI), Stress-Inoculated (SI) and Control-Inoculated (CI). The SI and CI groups were inoculated with tumor cells and the SNI group with vehicle. SNI and SI were exposed to social stress with an anosmic intruder six (T1) and twenty one (T2) days after inoculation and their behavior was analyzed. After T2, subjects were put down and the pulmonary metastatic foci counted. SI developed greater pulmonary metastasis than CI, indicating an effect of stress despite the animal's dominant status. Active animals developed less pulmonary metastasis than their passive counterparts. No differences were found in social behavior at T1. Differences were found, however, in some behavioral categories at T2 between SI and SNI, and between active and passive animals. These differences indicate an effect of tumor development on social behavior that is more evident in passive subjects.     

Antecedents and reactions to health-related social control

A model of the antecedents and reactions to health-related social control is proposed. This model suggests health behavior characteristics, including type, frequency, and severity of consequences, are social control antecedents. Social control is then thought to elicit better health behavior and emotions. Attributions to explain social control are proposed to effect emotional reactions and behavior. Undergraduates read hypothetical scenarios to test the proposed model. Study 1 found that health-compromising behaviors and behaviors with more severe consequences elicited more social control. Study 2 found that, compared to negative tactics, positive social control tactics elicited more behavior change, and compared to social/appearance concerns, attributions to health elicited positive emotions. Attributions did not moderate the impact of social control on emotions or behavior.     

Genetic and experiential manipulation of fear-related behavior in Japanese quail chicks (Coturnix coturnix japonica)

We examined effects of environmental enrichment and regular handling on fear-related responses in chicks of Japanese quail (Coturnix coturnix japonica) selected over several generations for short or long tonic immobility (STI and LTI, respectively). STI chicks froze less, vocalized and walked sooner and more in an open field, emerged sooner from a hole-in-the-wall box, and showed shorter TI reactions than did chicks of the LTI line. Similarly, environmental enrichment reduced silence and inactivity in the open field, accelerated emergence, and attenuated TI. Regular handling promoted open-field vocalization and reduced the duration of TI but exerted no other significant effects. Principal component analysis showed that the responses in the 3 tests were not independent, which implies that they measured the same underlying factor. The genetic and experiential manipulation of stimulus-specific fears and of general fearfulness is discussed.     

Environmental and cognitive factors in social play

The impact of differing play environments, as well as cognitive and social egocentrism factors, on the social play of preschoolers was examined. Fifteen boys and thirteen girls (55 months of age) were allowed free access to two distinctly different environments containing play materials which were aimed at exercising either big or fine muscle coordination. The children's cognitive abilities and social egocentrism were also measured. The results indicate that the play environment strongly influenced the type of social play as well as the size of the play groups. Differences in cognitive level and social egocentrism influenced the children's choice of play environment, suggesting an organism-environment interaction in the children's social play. The results indicate that today's generation of children may not be less social in their play, as Barnes has suggested, but that differences between studies may be a consequence of differing play environments and not generational differences.     

Psychosocial factors affecting custodial and visitation arrangements

This article reviews psychosocial factors that may influence the custodial and access arrangements for children during separation, divorce and remarriage. Custodial arrangements for children following the divorce of their parents are discussed. Elements to consider in determining the custodial arrangement that provides for the best interests of children include child, adult, interpersonal and social environmental factors. It is recommended that all of these factors be considered in drafting a custodial agreement that will serve the best interest of children following a marital and family breakup or remarriage.