Facilitation of the effect testosterone on male sexual behavior in rats deprived of REM sleep

The possibility of rapid eye movement sleep deprivation (REMd) altering the effect of testosterone on masculine sexual behavior was investigated. Adult castrated male Wistar rats with no sexual experience were randomly assigned to the following three groups: REMd (using the water tank technique) for 7 days, large platform control for 7 days, and undisturbed sleep control. All subjects were treated with 1 mg testosterone propionate daily for 14 days. Masculine sexual behavior was assessed 3 consecutive days prior to steroid administration and was evaluated daily during the treatment. Frequencies and latencies of mounts, intromissions, and ejaculations, as well as the postejaculatory refractory period were recorded. One hundred percent of the REMd subjects presented mounts, intromissions, and ejaculations sooner than the control group. In almost all parameters, a clear facilitation of sexual activity was observed in the REMd group.     

Subjective Sleep Disturbances in Sexual Assault Survivors: Associations With Trauma and Posttraumatic Stress Disorder Symptom Severity

Prior work implicates sleep disturbance in the development and maintenance of posttraumatic stress disorder (PTSD). However, the majority of this literature has focused on combat veteran men, and limited work has examined links between sleep disturbance and PTSD symptoms in sexual assault survivors. This is a notable gap in the literature, as sexual trauma is disproportionately likely to result in PTSD and is more common in women. We sought to examine the relations between subjective sleep disturbance, sexual assault severity, and PTSD symptoms in a sample of sexual assault survivors with PTSD (PTSD+), without PTSD (PTSD-), and healthy controls. The sample (N = 60) completed the Insomnia Severity Index and prospectively monitored their sleep for 1 week using the Consensus Sleep Diary. The sexual assault survivors also completed the Sexual Experiences Survey and PTSD Checklist-5. Results of group comparisons found that the PTSD+ group reported significantly higher insomnia symptoms, longer sleep onset latency, more nocturnal awakenings, and lower sleep quality compared to the healthy control group and higher insomnia symptoms compared to the PTSD- group. Results of regression analyses in the sexual assault survivors found that insomnia symptoms and number of nocturnal awakenings were significantly associated with higher PTSD symptoms, and sexual assault severity was significantly associated with higher insomnia symptoms, longer sleep onset latency, and lower sleep quality. These findings highlight specific features of sleep disturbance that are linked to trauma and PTSD symptom severity among sexual assault survivors.     

Presenting problems of sexually abused girls receiving psychiatric services

Twenty-three behaviors among those suggested in the literature to be associated with sexual abuse were studied in 195 girls, ages 2-18 years, who were consecutive admissions to three Midwestern mental health agencies. Results indicated that sexually inappropriate behaviors, sleep disturbance, depressed mood, and delinquent behavior occurred more frequently in young abuse victims than in clinic comparisons. Sexually inappropriate behaviors and running away appeared more often in older sexually abused girls, than they appeared in older clinic comparisons. These comparisons of the presenting problems of sexually abused and nonabused girls suggested there are few behavioral "markers" of sexual abuse in clinical samples and that sexual abuse may not be a unique contributing factor in the ontogeny of childhood psychopathology.     

REM sleep: A social bonding mechanism

It is proposed that REm sleep evolved, in part, to promote social bonding between (1) a mammalian infant and the mother and (2) sexual partners. The bonding hypothesis is consistent with the available evidence from psychobiologic studies of the attachment process in infants, with the known physiologic correlates of REM sleep, with the facts concerning the ontogeny and the phylogeny of REM sleep, and with phenomenological properties of dreams.     

Socio-Economic Status,Time Spending,and Sleep Duration in Indian Children and Adolescents

In this article physical activity, screen time, and academic work are studied as mediators between socio-economic status and sleep duration among school children in India. Participants were 268 school children aged 10–15 from Pune, India. They were sampled from private schools and impoverished public schools. We found that the highest socio-economic status children reported almost an hour and a half less sleep than their lowest socio-economic status counterparts. The lower socio-economic status children reported more physical activity and screen time, and the higher socio-economic status children reported spending more time on academic work. Although screen time was negatively related to sleep duration, academic work was the strongest mediator between socio-economic status and sleep duration. Physical activity was not a significant mediator. In India, academic work is a strong predictor of a lower sleep duration among children and adolescents.     

Residual effects of emotion are reflected in enhanced visual activity after sleep

Research has investigated how sleep affects emotional memory and how emotion enhances visual processing, but these questions are typically asked by re-presenting an emotional stimulus at retrieval. For the first time, we investigate whether sleep affects neural activity during retrieval when the memory cue is a neutral context that was previously presented with either emotional or nonemotional content during encoding. Participants encoded scenes composed of a negative or neutral object on a neutral background either in the morning (preceding 12 hours awake; wake group) or evening (preceding 12 hours including a night of sleep; sleep group). At retrieval, participants viewed the backgrounds without their objects, distinguishing new backgrounds from those previously studied. Occipital activity was greater within the sleep group than the wake group specifically during the successful retrieval of neutral backgrounds that had been studied with negative (but not neutral) objects. Moreover, there was enhanced connectivity between the middle occipital gyrus and hippocampus following sleep. Within the sleep group, the percentage of REM sleep obtained correlated with activity in the middle occipital gyrus, lingual gyrus, and cuneus during the successful retrieval of neutral backgrounds previously paired with negative objects. These results confirm that emotion affects neural activity during retrieval even when the cues themselves are neutral, and demonstrate, for the first time, that this residual effect of emotion on visual activity is greater after sleep and may be maximized by REM sleep.     

A review of mentation in REM and NREM sleep: "covert" REM sleep as a possible reconciliation of two opposing models

Numerous studies have replicated the finding of mentation in both rapid eye movement (REM) and nonrapid eye movement (NREM) sleep. However, two different theoretical models have been proposed to account for this finding: (1) a one-generator model, in which mentation is generated by a single set of processes regardless of physiological differences between REM and NREM sleep; and (2) a two-generator model, in which qualitatively different generators produce cognitive activity in the two states. First, research is reviewed demonstrating conclusively that mentation can occur in NREM sleep; global estimates show an average mentation recall rate of about 50% from NREM sleep--a value that has increased substantially over the years. Second, nine different types of research on REM and NREM cognitive activity are examined for evidence supporting or refuting the two models. The evidence largely, but not completely, favors the two-generator model. Finally, in a preliminary attempt to reconcile the two models, an alternative model is proposed that assumes the existence of covert REM sleep processes during NREM sleep. Such covert activity may be responsible for much of the dreamlike cognitive activity occurring in NREM sleep.     

Memory consolidation during sleep: interactive effects of sleep stages and HPA regulation

Sleep is critically involved in the consolidation of previously acquired memory traces. However, nocturnal sleep is not uniform but is subject to distinct changes in electrophysiological and neuroendocrine activity. Specifically, the first half of the night is dominated by slow wave sleep (SWS), whereas rapid eye movement (REM) sleep prevails in the second half. Concomitantly, hypothalamo-pituitary-adrenal (HPA) activity as indicated by cortisol release is suppressed to a minimum during early sleep, while drastically increasing during late sleep. We have shown that the different sleep stages and the concomitant glucocorticoid release are interactively involved in the consolidation of different types of memories. SWS-rich early sleep has been demonstrated to benefit mainly the consolidation of hippocampus-dependent declarative memories (i.e. facts and episodes). In contrast, REM sleep-rich late sleep was shown to improve in particular emotional memories involving amygdalar function, as well as procedural memories (for skills) not depending on hippocampal or amygdalar function. Enhancing plasma glucocorticoid concentrations during SWS-rich early sleep counteracted hippocampus-dependent declarative memory consolidation, but did not affect hippocampus-independent procedural memory. Preventing the increase in cortisol during late REM sleep-rich sleep by administration of metyrapone impaired hippocampus-dependent declarative memory but enhanced amygdala-dependent emotional aspects of memory. The data underscore the importance of pituitary-adrenal inhibition during early SWS-rich sleep for efficient consolidation of declarative memory. The increase in cortisol release during late REM sleep-rich sleep may counteract an overshooting consolidation of emotional memories.     

Dreaming without REM sleep

To test whether mental activities collected from non-REM sleep are influenced by REM sleep, we suppressed REM sleep using clomipramine 50mg (an antidepressant) or placebo in the evening, in a double blind cross-over design, in 11 healthy young men. Subjects were awakened every hour and asked about their mental activity. The marked (81%, range 39-98%) REM-sleep suppression induced by clomipramine did not substantially affect any aspects of dream recall (report length, complexity, bizarreness, pleasantness and self-perception of dream or thought-like mentation). Since long, complex and bizarre dreams persist even after suppressing REM sleep either partially or totally, it suggests that the generation of mental activity during sleep is independent of sleep stage.     

The case against memory consolidation in REM sleep

We present evidence disputing the hypothesis that memories are processed or consolidated in REM sleep. A review of REM deprivation (REMD) studies in animals shows these reports to be about equally divided in showing that REMD does, or does not, disrupt learning/memory. The studies supporting a relationship between REM sleep and memory have been strongly criticized for the confounding effects of very stressful REM deprivation techniques. The three major classes of antidepressant drugs, monoamine oxidase inhibitors (MAOIs), tricyclic antidepressants (TCAs), and selective serotonin reuptake inhibitors (SSRIs), profoundly suppress REM sleep. The MAOIs virtually abolish REM sleep, and the TCAs and SSRIs have been shown to produce immediate (40-85%) and sustained (30-50%) reductions in REM sleep. Despite marked suppression of REM sleep, these classes of antidepressants on the whole do not disrupt learning/memory. There have been a few reports of patients who have survived bilateral lesions of the pons with few lingering complications. Although these lesions essentially abolished REM sleep, the patients reportedly led normal lives. Recent functional imaging studies in humans have revealed patterns of brain activity in REM sleep that are consistent with dream processes but not with memory consolidation. We propose that the primary function of REM sleep is to provide periodic endogenous stimulation to the brain which serves to maintain requisite levels of central nervous system (CNS) activity throughout sleep. REM is the mechanism used by the brain to promote recovery from sleep. We believe that the cumulative evidence indicates that REM sleep serves no role in the processing or consolidation of memory.     

The Sexual Double Standard: Fact or Fiction?

In contemporary society it is widely believed that men are socially rewarded for sexual activity, whereas women are derogated for sexual activity. To determine whether a sexual double standard exists, both undergraduate (n = 144) and Internet (n = 8,080) participants evaluated experimental targets who were described as either male or female and as having a variable number of sexual partners. Targets were more likely to be derogated as the number of sexual partners increased, and this effect held for both male and female targets. These results suggest that, although people do evaluate others as a function of sexual activity, people do not necessarily hold men and women to different sexual standards.     

Between the sheets: Investigating young adults' communication during sexual activity

The present study investigated young adults' self‐reported communication during sexual activity and its link to sexual and relational outcomes. The associations between two forms of communication during sexual activity (i.e., positive relational disclosures and erotic talk) and orgasm and relationship satisfaction were explored. Additionally, the study tested whether orgasm mediated the association between communication during sexual activity and relationship satisfaction. Three‐hundred and nineteen young adults (237 women, 82 men) ranging in age from 18–32 years (M = 19) completed a survey within 2 hours of a recent sexual episode addressing their communication during sexual activity. Results revealed that positive relational disclosures, but not erotic talk, predicted the likelihood of orgasm, controlling for participants' biological sex. More specifically, individuals who disclosed more positive feelings during sexual activity were more likely to orgasm. Additionally, the more individuals disclosed positive thoughts and feelings for their partners during sexual activity or the more they engaged in mutualistic erotic talk that included intimacy and bonding, the higher their reported relationship satisfaction after sexual activity. The implications of these findings for research on sexual satisfaction, relational health, and the post sex disclosures model are discussed.     

Factors associated with the sexual experiences of underprivileged Mexican adolescents.

This study investigated factors associated with the sexual experiences of 523 underprivileged Mexican adolescents. Approximately 41% of the males and 24% of the females were sexually active, with more than half not using contraceptives. Multivariate logistic regression analysis revealed that sexual activity was strongly associated with age, knowledge about sexually transmitted diseases, and attitudes toward sexuality. Positive affective responsiveness in the family was associated with sexual activity and number of sexual partners. Family problem solving and roles were also associated with sexual activity. The use of contraceptives was negatively related to affective involvement between parents, and being a victim of sexual abuse was negatively associated with number of persons in the family. These findings support the notion that affective environment within the family is a factor in adolescent sexuality.     

Role of Religion in Preventing Youth Sexual Activity in Malaysia: A Mixed Methods Study

One of the popular approaches of preventing youth sexual activity in Malaysia is using religion to promote premarital sexual abstinence. Despite this intervention, youth continue to practise premarital sex. Thus, the purpose of this exploratory mixed methods study was to understand the role of religion on sexual activity among college students in Klang Valley, Malaysia. A self-administered questionnaire survey to determine the relationship between religiosity and youth sexual activity was carried out on 1026 students recruited from 12 randomly selected colleges. Concurrently, face-to-face interviews were conducted on 15 students to explore how religiosity had influenced their decision on sexual activity. The survey data were analysed using logistic regression, while the qualitative data from the interviews were examined using thematic analysis with separate analysis for each gender. Both quantitative and qualitative results were then compared and integrated. Religious activity significantly reduced the risk of continuing sexual activity among female students (AOR = 0.67, CI = 0.47, 0.95, p = 0.02) but not male students. There was no significant relationship of religious affiliation and intrinsic religiosity (inner faith) to sexual activity by gender. Having faith in religion and strong sexual desire were the main themes that explained participants’ sexual behaviour. Engaging in religious activity might be effective at preventing female students from being sexually active. However, when sexual urges and desires are beyond control, religiosity might not be effective.     

Heart-rate variability during nocturnal sleep in mentally retarded children.

Heart-rate variability in four normal and 30 mentally retarded children was investigated during nocturnal sleep. In four normal and 25 mentally retarded subjects, a high frequency component defined as spectral activity between 0.15 and 0.5 Hz was found in the compressed spectral array of the power spectra. A periodic change was seen in the high frequency component which corresponded precisely to the sleep cycle. However, four children with mental retardation did not show normally expected changes in the high frequency components specific to the sleep stages: a quantity of the high frequency component in only one sleep cycle (n=2; 6 mo. and 3 yr., 8 mo.), a decreased quantity and discontinuity of the high frequency component in only the second sleep cycle (n=1; 1 yr., 2 mo.), and no high frequency component in any sleep cycle (n=1; 3 mo.) These findings suggest that some mentally retarded children have an abnormal parasympathetic nervous activity.     

The reciprocal relation between sleep and memory in infancy: Memory‐dependent adjustment of sleep spindles and spindle‐dependent improvement of memories

Sleep spindle activity in infants supports their formation of generalized memories during sleep, indicating that specific sleep processes affect the consolidation of memories early in life. Characteristics of sleep spindles depend on the infant's developmental state and are known to be associated with trait‐like factors such as intelligence. It is, however, largely unknown which state‐like factors affect sleep spindles in infancy. By varying infants’ wake experience in a within‐subject design, here we provide evidence for a learning‐ and memory‐dependent modulation of infant spindle activity. In a lexical‐semantic learning session before a nap, 14‐ to 16‐month‐old infants were exposed to unknown words as labels for exemplars of unknown object categories. In a memory test on the next day, generalization to novel category exemplars was tested. In a nonlearning control session preceding a nap on another day, the same infants heard known words as labels for exemplars of already known categories. Central–parietal fast sleep spindles increased after the encoding of unknown object–word pairings compared to known pairings, evidencing that an infant's spindle activity varies depending on its prior knowledge for newly encoded information. Correlations suggest that enhanced spindle activity was particularly triggered, when similar unknown pairings were not generalized immediately during encoding. The spindle increase triggered by previously not generalized object–word pairings, moreover, boosted the formation of generalized memories for these pairings. Overall, the results provide first evidence for a fine‐tuned regulation of infant sleep quality according to current consolidation requirements, which improves the infant long‐term memory for new experiences.     

Daily activities and sleep quality in young adults

Daily activity levels were investigated as related to sleep quality in young adult college students aged 18 to 30 years. 85 participants (20 men, 65 women) completed the Young Adult Daily Activity Scale (YADAS). This 37-item checklist has 34 items based on focus group discussion points of college students' typical daily activities and three blank items for students to include their daily activities if not in the listing. The tabulation of type and amount of waking daily activities represents a unique measurement of factors that may affect sleep quality. The participants also rated their typical sleep quality using a standard 5-point scale (low indicating poor sleep). Correlations of sleep ratings and activities were not significant.     

"Central arousal" and sexual responsiveness in the snail, Helix aspersa

In molluscs, a "central arousal" system is thought to positively modulate both an animal's level of activity and its behavioral responsiveness. This hypothesis is examined in Helix aspersa by testing the relationships between activity, feeding, and sexual behavior. Activity, feeding, and mating exhibit parallel daily rhythms. Snails are most active, and eat and mate most frequently, during scotophase and the first 3 h of photophase. Handling and injections of serotonin (5 x 10(-7) m/kg body wt) increase general activity. Inducing activity during late photophase increases food consumption, but it does not induce sexual activity. Moreover, serotonin and handling have no effect on sexual arousal; treated snails show no increase in genital eversion stage and require the same length of courtship as controls. If snails are sexually deprived, increasing activity in late photophase does increase copulation frequency, but snails do not copulate more frequently than do unhandled snails tested during early photophase. These results suggest that while manipulations thought to increase central arousal do increase activity and responsiveness to food stimuli, they do not directly affect sexual proclivity or sexual arousal. Moreover, the relationship between feeding and sexual behavior differs between Helix and Aplysia. This difference between the two species may be related to the differences in their reproductive strategies.     

Patterns of marijuana use and physical health indicators among Canadian youth

We examine how trajectories of marijuana use in Canadian youth (ages 15 to 28) are related to physical health indicators in adolescence and young adulthood. Youth were initially recruited in 2003 (N = 662; 48% male; ages 12 to 18) and followed for six waves. Five trajectories of marijuana use (Abstainers-29%, Occasional users-27%, Decreasers-14%, Increasers-20% and Chronic users-11%) were identified. Chronic users reported more physical symptoms, poorer physical self-concept, less physical activity, poorer eating practices, less sleep, and higher number of sexual partners during adolescence than other classes. Decreasers also reported poorer physical self-concept and poorer eating practices than abstainers. Other trajectory classes showed few significant health problems. Chronic users also reported more acute health problems (i.e. serious injuries, early sexual debut, higher number of sexual partners, greater likelihood of having a STI) in young adulthood than all other classes contributing to costs of healthcare. Youth who engage in early, frequent and continued use of marijuana from adolescence to young adulthood are at-risk of physical health problems in adolescence and young adulthood.     

Brain-mind states: reciprocal variation in thoughts and hallucinations

The exclusion of thinking from recent studies of sleep mentation has hindered a full appreciation of how cognitive activity differs across the states of waking and sleep. To overcome this limitation, this study investigated thoughts and hallucinations using experience sampling, home-based sleep-wake monitoring, and formal analyses of the psychological data. The prevalence of thoughts decreased gradually from waking through sleep onset and non-REM sleep, to reach its nadir in REM sleep, whereas hallucinations increased sharply across these states. Furthermore, multiple occurrences of hallucinations but not of thoughts increased significantly from sleep onset through non-REM sleep, to a peak in REM sleep. This reciprocity in thoughts and hallucinations might reflect a progressive shift from high to low aminergic-to-cholinergic neuromodulatory ratios across wake-sleep states, accompanied by an array of changes in the regional activation patterns of the brain.