Sequence-based methods for detecting and evaluating the human gut mycobiome.

UNLABELLED: We surveyed the fungal microbiota in 16 faecal samples from healthy humans with a vegetarian diet. Fungi were identified using molecular cloning, 454 pyrosequencing and a Luminex analyte-specific reagent (ASR) assay, all targeting the ITS region of the rRNA genes. Fungi were detected in each faecal sample and at least 46 distinct fungal operational taxonomic units (OTUs) were detected, from two phyla - Ascomycota and Basidiomycota. Fusarium was the most abundant genus, followed by Malassezia, Penicillium, Aspergillus and Candida. Commonly detected fungi such as Aspergillus and Penicillium, as well as known dietary fungi Agaricus bisporus and Ophiocordyceps sinensis, are presumed to be transient, allochthonous members due to their abundance in the environment or dietary associations. No single method identified the full diversity of fungi in all samples; pyrosequencing detected more distinct OTUs than the other methods, but failed to detect OTUs in some samples that were detected by cloning and/or ASR assays. ASRs were limited by the commercially available assays, but the potential to design new, optimized assays, coupled with speed and cost, makes the ASR method worthy of further study. SIGNIFICANCE AND IMPACT OF THE STUDY: Fungi play a role in human gut ecology and health. The field lags immensely behind bacterial gut microbiota research, and studies continue to identify new fungi in faecal samples from healthy humans. However, many of these 'new' species are incapable of growth in the human GI tract, let alone making a meaningful contribution to the gut microbial community. Fungi actually inhabiting and impacting the gut likely constitute a small set of species, and an optimized, targeted, probe-based assay may prove to be the most sensible way of quantifying their abundances.

Homophobia and physical aggression toward homosexual and heterosexual individuals.

This study examined the relationship between homophobia (defined as self-reported negative affect, avoidance, and aggression toward homosexuals) and homosexual aggression. Self-identified heterosexual college men were assigned to homophobic (n = 26) and nonhomophobic (n = 26) groups on the basis of their scores on the Homophobia Scale (HS; L. W. Wright, H. E. Adams, & J. A. Bernat, 1999). Physical aggression was examined by having participants administer shocks to a fictitious opponent during a competitive reaction time (RT) task under the impression that the study was examining the relationship between sexually explicit material and RT. Participants were exposed to a male homosexual erotic videotape, their affective reactions were assessed, and they then competed in the RT task against either a heterosexual or a homosexual opponent. The homophobic group reported significantly more negative affect, anxiety, and anger-hostility after watching the homosexual erotic videotape than did the nonhomophobic group. Additionally, the homophobic group was significantly more aggressive toward the homosexual opponent, but the groups did not differ in aggression toward the heterosexual opponent.

Sexually aggressive and nonaggressive men: sexual arousal and judgments in response to acquaintance rape and consensual analogues.

Self-identified sexually aggressive (SA) and nonaggressive (NA) college men listened to audiotape analogues of consensual sexual intercourse and acquaintance rape. Phallometric and decision-latency methodology was used to examine sexual arousal and decisions to stop sexual advances in each scenario. Both groups showed increases in penile response to the consensual scenario. Consistent with the inhibition model of sexual aggression, the SA group showed greater sexual arousal and failed to inhibit responding when force was introduced in the rape, whereas the NA group exhibited less arousal and greater inhibition to force. The SA group allowed the rape to continue significantly longer than the NA group. These effects were greatly magnified in SA men who endorsed high calloused sexual beliefs, implying that a cognitive set that justifies sexual aggression and lacks victim empathy may disinhibit sexual arousal and potentiate coercive decision making.

The effect of alcohol on the responses of sexually coercive and noncoercive men to an experimental rape analogue.

This study examined the impact of the psychological and pharmacological effects of alcohol on the ability of sexually coercive and noncoercive men to discriminate when a female wants a partner to stop sexual advances. In a 2 (alcohol vs. no alcohol) x 2 (expectancy vs. no expectancy) x 2 (sexually coercive vs. noncoercive status) randomized factorial design, male college students were exposed to an audiotape of a date rape. Participants who consumed, or expected to consume, alcohol took significantly longer to determine that the man should refrain from attempting further sexual contact. In addition, nonsexually coercive participants assigned to conditions in which they expected to consume alcohol responded similarly to their sexually coercive counterparts in their responses. The implications of these findings are discussed.

Sexual arousal to erotic and aggressive stimuli in sexually coercive and noncoercive men.

Sexual arousal to erotic stimuli depicting various levels of force were examined among college men. Study 1 used phallometric indices to measure penile circumferential change during combined audio-tape and slide presentations varying in degree of force. The results indicated that the sexually coercive group exhibited more penile tumescence than controls to scenes involving verbal pressure and verbal threats. Analyses across time blocks suggested that control participants inhibited sexual arousal with the introduction of force cues but that the sexually coercive group did not. Study 2 was a replication of Study 1 without slides. Both groups showed increases in penile tumescence in response to the consent scenario. Only the sexually coercive men demonstrated significant tumescence in response to force scenarios. The results indicated that the sexually coercive males had a lower threshold for arousal to sexual cues and did not inhibit sexual arousal when force cues were introduced.

Is homophobia associated with homosexual arousal?

The authors investigated the role of homosexual arousal in exclusively heterosexual men who admitted negative affect toward homosexual individuals. Participants consisted of a group of homophobic men (n = 35) and a group of nonhomophobic men (n = 29); they were assigned to groups on the basis of their scores on the Index of Homophobia (W. W. Hudson & W. A. Ricketts, 1980). The men were exposed to sexually explicit erotic stimuli consisting of heterosexual, male homosexual, and lesbian videotapes, and changes in penile circumference were monitored. They also completed an Aggression Questionnaire (A. H. Buss & M. Perry, 1992). Both groups exhibited increases in penile circumference to the heterosexual and female homosexual videos. Only the homophobic men showed an increase in penile erection to male homosexual stimuli. The groups did not differ in aggression. Homophobia is apparently associated with homosexual arousal that the homophobic individual is either unaware of or denies.

Somatothymia in chronic pain patients.

Somatothymia is the use of somatic language to communicate affective distress. A total of 152 chronic pain patients completed a systems review checklist and the Minnesota Multiphasic Personality Inventory. Associated features of somatic symptoms and the meaningfulness of somatic symptoms as a communication, common physical areas of somatic focus, patterns of affective distress in high and low somatothymics, and the utility of select variables classifying high and low somatothymics were evaluated. The results indicate that a systems review checklist can be used as a quick, useful, and initial screen for somatothymia and that somatic symptoms can in fact communicate affective distress.

Validity and ethics of penile circumference measures of sexual arousal: a reply to McConaghy.

McConaghy (1989) argued that the validity of penile circumference responses (PCRs) is at best unestablished and that penile volume responses (PVRs) have been demonstrated to be clearly superior indices of sexual arousal and orientation. In his critique, McConaghy stated that (i) penile erection has been incorrectly identified with sexual arousal, (ii) that PCRs have not been shown to accurately discriminate between divergent patterns of sexual arousal (including paraphilias), (iii) that the methodologies used to compare the two types of transducers are inappropriate, and (iv) that PCRs should not be used for diagnostic and treatment decisions. In this paper, McConaghy's criticisms are reviewed in the context of the existing literature on the subject. Although PCRs and PVRs involve different methodologies, they generally yield results that bear more similarities than differences. Furthermore, there is an extensive and growing literature on the use of PCR measures with various paraphilias. Several of McConaghy's arguments should be considered tentative while others are clearly unsubstantiated. Most of McConaghy's concerns over the validity and uses of PCR measures are empirical questions. Suggestions for future research are offered.

Voluntary control of penile tumescence among homosexual and heterosexual subjects.

Voluntary control of erectile responses represents a major threat to the validity of penile plethysmography. This study was designed to determine whether individuals can mimic a sexual orientation that differs from their actual sexual orientation. Since the presumed mechanism underlying voluntary control of penile tumescence involves a shift in attentional focus, a recall test was employed to assess the relationship between the ability to influence erectile responses and recall of critical test stimuli. Homosexual and heterosexual subjects were exposed to sexual materials under standard and "faking" instructions. The faking instructions consisted of asking subjects to suppress erectile responses to preferred stimuli and to enhance penile tumescence in the presence of nonpreferred stimuli. Across groups, results revealed some degree of suppression of erections but no significant enhancement of erections. Self-reported cognitive arousal under both conditions was consistent with erectile data. However, subjects' perceived control over erectile responses tended to be greater than their actual performance. No significant differences in recall were obtained. The recall procedure appears to interfere with subjects' ability to control erectile responses. Implications for clinical applications of penile plethysmography are summarized with suggestions for future research.

An identification of low back pain groups using biobehavioral variables.

A multivariate predictive model of low back pain (LBP) was developed. Following a semi-structured interview, 73 participants were assigned to dysfunctional chronic low back pain (DCLBP), functional chronic low back pain (FCLBP), acute low back pain (ALBP), and healthy control (HC) groups. All participants underwent a comprehensive physical, psychophysiological, and psychological evaluation. Multivariate analyses indicated no psychophysiological, few physical, and many psychological differences among the groups. The DCLBP group was found to be most impaired in flexion (p<.001), and the HC group performed the most total work (ft-lb) in extension (p<.001). Psychologically, the DCLBP group displayed greater levels of emotional distress and characterological disturbances and were more functionally impaired (p<.001). Few differences between FCLBP and HC were found. A classification analysis using physical and psychological variables correctly classified 83.3% of DCLBP patients, and it was found that the ALBP group was heterogeneous with some patients having a dysfunctional profile and other patients having a functional profile. The psychological variables were more potent predictors of group membership than were the physical variables. These findings indicate that potential DCLBP and FCLBP patients can be identified shortly following an injury, suggesting important implications for assessment and treatment of low back pain in general, and more specifically, for reducing health care costs and human suffering.

Patterns of sexual arousal of accused child molesters involved in custody disputes.

Penile plethysmography was used to examine sexual preferences of individuals accused of child molestation in the course of custody conflicts. Information regarding the alleged offenders, victims, and sex offense was gathered. In comparison to accused offenders who are not engaged in custody disputes, the subjects were more often accused of sexually abusing a younger child who was a biological relative. The source of accusations was usually the mother. Additionally, the custody-dispute subjects were less likely to have a prior criminal history. Penile tumescence data suggested that the subjects involved in custody disputes were less sexually aroused by children than those subjects who were not involved in custody conflicts. However, the results revealed that in both groups a substantial number of subjects responded equally or more to the child stimuli. In sum, the alleged offenders involved in custody disputes appeared less deviant on several measures.

Detection of noncontingent feedback in EMG biofeedback.

Noncontingent feedback is frequently used as a placebo control procedure in biofeedback research. Researchers, however, have criticized this procedure for lacking credibility because of easy detection. The present study examined detection of false feedback in biofeedback with EMG. Contingent feedback (CF), truly random false feedback (FF), and controlled false feedback (CFF) groups were compared for changes in EMG levels, report of inaccurate feedback, and report of learning muscle activity reduction. The results indicated that FF procedures are easily detected; therefore, difference found between the FF and CF groups may be influenced by extraneous variables. The CFF group did not detect false feedback, but subjects reported some suspicions in later trials. With more trials, CFF may have also been detected. These results indicate a need for more attention to appropriate placebo control procedures in evaluating the parameters and efficacy of biofeedback.

Pain responsivity in women with premenstrual syndrome across the menstrual cycle.

11 women with a clinical diagnosis of Premenstrual Syndrome (PMS) and 10 control women with no such diagnosis were compared on pain threshold and pain-tolerance measures in the intermenstrual and premenstrual phases of their menstrual cycles. No significant differences were found between the groups for behavioral measures of pain sensitivity. Ratings of pain intensity, however, were higher in both phases for the PMS group.

Autonomic arousal and pain sensitivity in women with premenstrual syndrome at different phases of the menstrual cycle.

Eleven women with a clinical diagnosis of premenstrual syndrome (PMS) and ten non-PMS control women were compared on physiological measures in the intermenstrual and premenstrual phases of their menstrual cycle. Heart rate (HR) and skin conductance level (SCL) were monitored during baseline conditions and in response to a stressful laboratory procedure. Analyses for HR revealed a three-way interaction (groups X phase X tests) which approached significance indicating that the PMS group was generally lower during the intermenstrual testing but was higher in the premenstrual phase. No significant differences were observed on behavioral measures (pain threshold, pain tolerance) between the groups. Pain intensity ratings were found to be overall higher in the PMS group irrespective of menstrual cycle phase. The role of cognitive-perceptual processes is discussed in the context of the acquisition and maintenance of PMS symptomatology.

Can migraine headaches be modified by operant pain techniques?

Migraine headaches are a common problem with many individuals and are usually treated by drug and/or biofeedback therapies. The following case history discussed the implementation of an operant approach to the modification of migraine headache, assumed to be associated with secondary gain and unresponsive to other treatment procedures. The operant program described below resulted in the elimination of head pain behaviors and a correlated increase in prosocial and well behaviors.

Jealousy: loss of relationship rewards, loss of self-esteem, depression, anxiety, and anger.

White's (1981) theory of romantic jealousy states that the loss (or anticipated loss) of a romantic partner to a rival causes two kinds of suffering: loss (or anticipated loss) of relationship rewards and loss (or anticipated loss) of self-esteem. Elaborating this theory, we proposed that loss of relationship rewards causes depression, whereas loss of self-esteem causes anxiety and anger. General support was found for White's theory and the elaborations, but not for the hypothesis that the loss of self-esteem causes anxiety. Anxiety may be a product of both loss of self-esteem and loss of relationship rewards.

Modification of disease phobia using a multifaceted exposure program.

By the use of a multifaceted exposure program that lasted 16 weeks, a 27-year-old male was treated for debilitating and irrational fears of having a heart attack. The subject reported reductions in daily anxiety ratings and Valium intake at midtreatment and further reductions at the conclusion of treatment. These changes were maintained at 6- and 12-month followup assessments. The subject's reports were confirmed by his spouse. The results are discussed in terms of the behavioral characteristics and etiology of disease phobia.