Pornography, videotape and the Internet

Pornography has had a significant role in the promotion and diffusion of new communication technologies. New technologies have also altered the nature of pornography in the last few decades. These technologies include VCRs, camcorders, Minitel, computers, and the Internet. Pornographic products have served to stimulate interest in these new technologies, despite their higher initial costs. The attractions include greater perceived privacy and easier access. As each of these technologies matures and prices drop, the importance of pornographic products diminishes relatively, but not absolutely. Another pattern is the elimination of the distinctions among producers, distributors, and consumers as do-it-yourself video and computers have permitted a “democratization” of pornography. At the risk of appearing indifferent to moral issues, the author focuses on pornography's importance in diffusing new technologies (VCRs, camcorders, Minitel, computers, and the Internet), and how these technologies have reshaped the nature of pornography. Driving this transformation have been the great capitalist engines of innovation and the quest for profits. Like war, pornography has served as an agent of change for both, and similarly benefitted greatly     

The neuronal growth-associated protein GAP-43 interacts with rabaptin-5 and participates in endocytosis

Structural plasticity of nerve cells is a requirement for activity-dependent changes in the brain. The growth-associated protein GAP-43 is thought to be one determinant of such plasticity, although the molecular mechanism by which it mediates dynamic structural alterations at the synapse is not known. GAP-43 is bound by calmodulin when Ca2+ levels are low, and releases the calmodulin when Ca2+ levels rise, suggesting that calmodulin may act as a negative regulator of GAP-43 during periods of low activity in the neurons. To identify the function of GAP-43 during activity-dependent increases in Ca2+ levels, when it is not bound to calmodulin, we sought proteins with which GAP-43 interacts in the presence of Ca2+. We show here that rabaptin-5, an effector of the small GTPase Rab5 that mediates membrane fusion in endocytosis, is one such protein. We demonstrate that GAP-43 regulates endocytosis and synaptic vesicle recycling. Modulation of endocytosis by GAP-43, in association with rabaptin-5, may constitute a common molecular mechanism by which GAP-43 regulates membrane dynamics during its known roles in activity-dependent neurotransmitter release and neurite outgrowth.     

Pregnancy block in house mice (Mus domesticus) as a function of t-complex genotype: Examination of the mate choice and male infanticide hypotheses.

Pregnancy block, whereby recently mated female mice abort their pregnancies when exposed to novel (strange) males, was studied in house mice (Mus domesticus) differing in t-complex genotype; t-mutations are deleterious and +/t females avoid +/t males as mates. The results of Experiment 1, in which the genotype of the female, stud male, and strange male was systematically varied, showed that pregnancy block was most frequent when the strange male was +/+. Because this effect was not enhanced among +/t females when stud males were +/t, the results cannot clearly be explained by the hypothesis that pregnancy block is a manifestation of mate choice. Moreover, the "strange male" effect in Experiment 1 is unlikely to be a female response correlated with the risk of male infanticide, as +/+ and +/t males did not differ in their infanticidal tendencies (Experiments 2 & 3). Alternative hypotheses, including a modified version of the male choice hypothesis, are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Effects of pre- and postpubertal social experience on sexual and social behavior in male and female brown lemmings (Lemmus sibiricus).

In 3 studies, male and female brown lemmings were either isolated at weaning (18 days) or then housed with siblings for another 10 days before being isolated. Before testing for sexual behavior at the age of 75–103 days, half of each group of males received a series of exposures to estrous females and half of each group of females was housed with a stud male. The results of mating tests indicate that whereas prior sexual experience facilitated subsequent copulatory behavior in both sexes, prepubertal interactions subsequently facilitated contact social and sexual behavior in males but did not increase the behavioral scores of females, who engaged in high levels of sexual behavior regardless of prepubertal experience. The effect of prior copulatory activity on male sexual performance could not be attributed to increasing age (i.e., maturational processes) because the behavior of males tested once but at different ages did not differ appreciably. Prepubertal social interaction appeared to predispose males to benefit from sexual experience later in life. (35 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Facsimile's false starts

The development of the 150-year-old facsimile concept is recounted. The factors that have made it such a popular technology are examined. Its evolution from use in niche markets only to broader use, and the shift of initiative in developing the technology to Japan in the 1980s, are discussed. Standards setting, advantages of facsimile, and legal issues are addressed     

Relationship between self-esteem and sensory (perceptual) constancy.

This study explored the relationship between self-esteem and sensory constancy, as measured by the perception of shape. 85 preadolescent males, representing 5 types of self-esteem, were individually asked to match a geometric shape with 1 of a graded series of rectangles. The procedure was intended to elicit judgments in accord with sensory rather than phenomenal constancy. These judgments were obtained under stress and nonstress orientations. The results, indicating that persons high in their estimates of personal worth are better able to attain sensory constancy, were limited to the stress condition. It is hypothesized that persons high in self-esteem can adapt more appropriately to instructions and adopt an analytic attitude excluding distracting stimuli. (20 ref.) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Effects of olfactory cues on sexual behavior in the brown lemming, Lemmus trimucronatus..

Tested 3 groups of 12 female lemmings each to determine the effects of odor familiarity on measures of reproductive behavior. A familiar odor (FO) group was exposed to the bedding of a particular male for 1 wk, then tested with that male. A 2nd female group (unfamiliar odor; UO) was exposed to the bedding of a male for 1 wk, then tested with a different male. A 3rd group (control; CO) was not exposed to male bedding prior to being tested with a male. The FO females engaged in higher frequencies of contact social behaviors than did UO and CO females. Males with FO females ejaculated more frequently than did the males with UO and CO females. Latencies to first display of sexual behaviors (female:lordosis; male:mount, thrust, and ejaculation) were lower for FO pairs. Results suggest that previous exposure of females to the odor of a given male facilitates sexual behaviors when such females are later paired with that male. (30 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Social olfaction in male brown lemmings (Lemmus sibiricus?=?trimucronatus) and collared lemmings (Dicrostonyx groenlandicus): II. Discrimination of mated and unmated females.

Four experiments were conducted with 32 brown and 80 collared male lemmings. When tested in a Y-maze olfactometer, both species preferred the odor of unmated receptive females to the odor of females with which they had just copulated. Similarly, sexually satiated Ss preferred the odor of an unmated receptive female to that of a strange female that had recently copulated with another male. Sexually experienced Ss without recent copulatory experience also demonstrated this preference, but sexually naive Ss did not. Sexually satiated collared lemmings preferred the odor of bedding from a novel estrous female to bedding from the female with which they had just copulated even when the bedding was collected before mating occurred. Results suggest that discrimination between prior mates and unmated females may be based on individual recognition as well as recognition of subclasses of females (i.e., mated vs unmated, familiar vs unfamiliar). (22 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)