Morphometric analysis of cervical neuroforaminal dimensions from C2-T1 using computed tomography of 1,000 patients.

BACKGROUND: Race and sex differences are not consistently reported in the literature. Fundamentally, anatomical differences of cervical neuroforaminal dimensions (CNFD) amongst these groups would be important to know. PURPOSE: To establish normative radiographic morphometric measurements of CNFD and uncover the influence of patient sex, race, and ethnicity while also considering anthropometric characteristics. STUDY DESIGN: Retrospective radiographic morphometric study. PATIENT SAMPLE: A total of 1,000 patients between 18 and 35 years of age who were free of spinal pathology. OUTCOME MEASURES: Foraminal height, axial width, and area of cervical neural foramen. METHODS: Cervical CTs were reviewed to measure CNFD, defined as follows: foraminal height, axial width, and area. Statistical analyses were performed to assess associations between CNFD, and patient height, weight, sex, race, and ethnicity. RESULTS: CNFD measurements followed a bimodal distribution pattern moving caudally from C2-T1. Irrespective of disc level, cervical CNFD were as follows: left and right widths of 6.6±1.5 and 6.6±1.5 mm, heights of 9.4±2.4 and 9.4±3.2 mm, and areas of 60.0±19.5 and 60.6±20.7 mm2. Left and right foraminal width were highest at C2-C3 and lowest at C3-C4. Left and right foraminal height were highest at C7-T1 and C6-C7, respectively and lowest at C3-C4. Left and right foraminal areas were highest at C2-C3 and lowest at C3-C4. Significant differences were observed for all CNFD measurements across disc levels. CNFD did not vary based on laterality. Significant CNFD differences were observed with respect to patient sex, race, and ethnicity. Male height and area were larger compared to females. In contrast, female foraminal width was larger compared to males. The Asian cohort demonstrated the largest foraminal widths. White and Hispanic patients demonstrated the largest foraminal heights and areas. Black patients demonstrated the smallest foraminal widths, heights, and areas. Patient height and weight were only weakly correlated with CNFD measurements across all levels from C2-T1. CONCLUSIONS: This study describes 36,000 normative measurements of 12,000 foramina from C2-T1. CNFD measurements vary based on disc level, but not laterality. Contrasting left- versus right-sided neuroforamina of the same level may aid in determining the presence of unilateral stenosis. Patient sex, race, and ethnicity are associated with CNFD, while patient anthropometric factors are weakly correlated with CNFD.

Evaluating the Presence of Disgust in Animals.

The emotion of disgust in humans is widely considered to represent a continuation of the disease-avoidance behavior ubiquitous in animals. The extent to which analogs of human disgust are evident in nonhuman animals, however, remains unclear. The scant research explicitly investigating disgust in animals has predominantly focused on great apes and suggests that disgust might be present in a highly muted form. In this review, we outline the main approaches to disgust. We then briefly discuss disease-avoidance behavior in nonhuman animals, proposing a set of criteria against which evidence for the presence or absence of disgust in animals can be evaluated. The resultant decision tree takes into account other plausible causes of avoidance and aversion when evaluating whether it is likely that the behavior represents disgust. We apply this decision tree to evaluate evidence of disgust-like behavior (e.g., avoidance of carrion and avoidance of feces-contaminated food) in several examples, including nonhuman great apes. Finally, we consider the large disparity between disgust in humans compared to muted disgust in other great apes, examining the possibility that heightened disgust in humans is a relatively recent cultural acquisition.

Normative Measurements of L1-S1 Segmental Angulation, Disk Space Height, and Neuroforaminal Dimensions Using Computed Tomography.

BACKGROUND AND OBJECTIVES: To establish normative anatomic measurements of lumbar segmental angulation (SA) and disk space height (DSH) in relation to neuroforaminal dimensions (NFDs), and to uncover the influence of patient demographic and anthropometric characteristics on SA, DSH, and NFDs. METHODS: NFDs, SA, and anterior, middle, and posterior DSH were measured using computed tomography of 969 patients. NFDs were defined as sagittal anterior-to-posterior width, foraminal height, and area. Statistical analyses were performed to assess associations among SA, DSH, NFDs, and patient height, weight, body mass index, sex, and ethnicity. RESULTS: SA and DSH measurements increased moving caudally from L1 to S1. Foraminal width decreased moving caudally from L1 to S1. Foraminal height and area demonstrated unimodal distribution patterns with the largest values clustered at L2-L3 on the right side and L3-L4 on the left. Significant differences in SA, DSH, and NFD measurements were observed based on the disk level. Inconsistent, marginal NFD differences were observed based on laterality. Across all disk levels, only weak-to-moderate correlations were observed between SA and DSH in relation to NFDs. Patient height, weight, and body mass index were only weakly associated with SA, DSH, and NFDs. Based on patient sex, significant differences were observed for SA, DSH, and NFD measurements from L1 to S1, with males demonstrating consistently larger values compared with females. Based on patient race and ethnicity, significant differences in SA and NFD measurements were observed from L1 to S1. CONCLUSION: This study describes 48 450 normative measurements of L1-S1 SA, DSH, and NFDs. These measurements serve as representative models of normal anatomic dimensions necessary for several applications including surgical planning and diagnosis of foraminal stenosis. Normative values of SA and DSH are not moderately or strongly associated with NFDs. SA, DSH, and NFDs are influenced by sex and ethnicity, but are not strongly or moderately influenced by patient anthropometric factors.

Surface anatomical landmarks for spine surgery: A CT-based study of the sternal notch and sternal angle in 1,035 patients.

BACKGROUND: Understanding the location of surface anatomical landmarks in relation to the cervical and thoracic spine is important for a wide array of clinical applications. The objective of this study was to investigate the influence of patient demographic and anthropometric characteristics on the locations of the sternal notch and sternal angle in relation to the spine using computed tomography (CT) of a large cohort of young adult patients without spinal pathology. METHODS: Vertebral levels corresponding to the sternal notch and sternal angle were analyzed using CT of 1,035 patients. Influences of patient height, weight, body mass index (BMI), sex, and ethnicity were assessed. RESULTS: 567 male and 468 female patients were included in this study. Mean patient height, weight, BMI, and age were 1.68 ± 0.11 m, 81.94 ± 24.39 kg, 27.79 ± 7.9 kg/m2, and 25.9 ± 5.9 years. Of the 1,035 patients, 495 were Hispanic or Latino, 321 were Caucasian, 130 were African American, 68 were Asian, 5 were identified as "other," and 16 did not have racial or ethnic data available. The location of the sternal notch in relation to the thoracic spine demonstrated a bimodal distribution pattern clustered at the T2 and T3 vertebral bodies. The location of the sternal angle in relation to the thoracic spine demonstrated a bimodal distribution pattern clustered at the T4 and T5 vertebral bodies. Moderate, negative correlations were observed between patient weight and location of the sternal notch (r = -0.447; p <.001) and sternal angle (r = -0.499; p <.001), respectively. Zero significant correlations were observed between patient height and location of the sternal notch (r = -0.045; p =.377) or sternal angle (r = -0.080; p =.229). A weak, negative correlation was observed between patient BMI and location of the sternal notch (r = -0.378; p <.001). A moderate, negative correlation was observed between patient BMI and location of the sternal angle (r = -0.445; p <.001). The locations of the sternal landmarks did not differ based on patient sex, race or ethnicity. CONCLUSIONS: The location of the sternal notch most frequently corresponds to the T2 or T3 vertebral body, while the sternal angle is most frequently located at the T4 or T5 vertebral body. Increased patient weight is associated with relatively cephalad sternal landmarks. Patient height, sex, and ethnicity are not associated with either sternal landmark.

Insulin receptor-inspired soluble insulin binder.

The insulin receptor (IR) is a 320 kDa membrane receptor tyrosine kinase mediating the pleiotropic actions of insulin, leading to phosphorylation of several intracellular substrates including serine/threonine-protein kinase (AKT1), and IR autophosphorylation. Structural details of the IR have been recently revealed. A high-binding insulin site, L1 (Kd =2 nM), consists of two distant domains in the primary sequence of the IR. Our design simplified the L1 binding site and transformed it into a soluble insulin binder (sIB). The sIB, a 17 kDa protein, binds insulin with 38 nM affinity. The sIB competes with IR for insulin and reduces by more than 50% phosphorylation of AKT1 in HEK 293 T cells, with similar effects on IR autophosphorylation. The sIB represents a new tool for research of insulin binding and signaling properties.

The Impact of the Covid-19 Pandemic on Disgust Sensitivity.

There have been few tests of whether exposure to naturalistic or experimental disease-threat inductions alter disgust sensitivity, although it has been hypothesized that this should occur as part of disgust's disease avoidance function. In the current study, we asked Macquarie university students to complete measures of disgust sensitivity, perceived vulnerability to disease (PVD), hand hygiene behavior and impulsivity, during Australia's Covid-19 pandemic self-quarantine (lockdown) period, in March/April 2020. These data were then compared to earlier Macquarie university, and other local, and overseas student cohorts, to determine if disgust sensitivity and the other measures, were different in the lockdown sample. The most consistent finding in the lockdown sample was of higher core disgust sensitivity (Cohen's d = 0.4), with some evidence of greater germ aversion on the PVD, and an increase in hand and food-related hygiene, but with little change in impulsivity. The consistency with which greater core disgust sensitivity was observed, suggests exposure to a highly naturalistic disease threat is a plausible cause. Greater disgust sensitivity may have several functional benefits (e.g., hand and food-related hygiene) and may arise implicitly from the threat posed by the Covid-19 pandemic.

I Should Have Known Better: Development of a Self-Report Measure of Gullibility.

The aim of this research was to explore the predictors of gullibility and to develop a self-report measure of the construct. In Studies 1 to 3, exploratory and confirmatory factor analyses were conducted on a large pool of items resulting in a 12-item scale with two factors: Persuadability and Insensitivity to cues of untrustworthiness. Study 4 confirmed the criterion validity of the scale using two distinct samples: scam victims and members of the Skeptics Society. Study 5 demonstrated positive relationships between gullibility and the self-reported persuasiveness of, and likelihood of responding to, unsolicited emails. Throughout the article, analyses of a variety of measures expected to converge with the scale provided evidence for its construct validity. Overall, these studies demonstrate that the construct of gullibility is distinct from trust, negatively related to social intelligence, and that the Gullibility Scale is a reliable and valid measure of gullibility.

Moral Violations and the Experience of Disgust and Anger.

Disgust is a natural defensive emotion that has evolved to protect against potential sources of contamination and has been recently linked to moral judgements in many studies. However, that people often report feelings of disgust when thinking about feces or moral transgressions alike does not necessarily mean that the same mechanisms mediate these reactions. The present study used functional magnetic resonance imaging (n = 22) to investigate whether core and moral disgusts entrain common neural systems. We provide evidence that: (i) activation of overlapping brain regions between core and moral disgust is the result of content overlap in the vignettes-core disgust elicitors-across conditions, and not from moral violations per se, and (ii) moral residue (i.e., the remaining or "residual" activation after the influence of core disgust elicitors have been taken into account) produced a pattern of activation that is more consistent with moral anger, than one of "residual disgust." These findings run contrary to the premise that our "moral center" is connected to the area of the brain in which physical revulsion is located.

The Role of Disgust in Male Sexual Decision-Making.

Sexual arousal is known to increase risky behaviors, such as having unprotected sex. This may in part relate to the emotion of disgust, which normally serves a disease avoidant function, and is suppressed by sexual arousal. In this report we examine disgust's role in sexual decision-making. Male participants received two study packets that were to be completed at home across two different time-points. Participants were asked to complete one packet in a sexually aroused state and the other in a non-aroused state. Participants were asked to rate: (1) arousal, (2) disgust, (3) willingness for sex, and (4) disease risk toward a range of female targets, which varied in level of potential disease risk (sex-worker vs. non sex-worker) and attractiveness. A measure of trait disgust was also included along with other related scales. Sexual arousal was associated with reduced disgust and reduced judgments of disease risk for all targets-these latter two variables being correlated-and with enhanced willingness to have sex with all of the depicted persons. Willingness to have sex when aroused (in contrast to non-aroused) was predicted by disease risk judgments and trait disgust, suggesting both direct (state) and indirect (trait) effects of disgust on sexual decision-making.

The effect of disgust on pain sensitivity.

Experiencing the emotion of disgust leads to delayed up-regulation of immune-related functions, increased core-body temperature and reduced appetite. These changes parallel those of the acute phase response, which occurs when a pathogen is detected by the immune system. Here we examined whether a further predicted aspect of the acute phase response is evident following disgust induction, namely increased pain sensitivity. Participants attended a two-session experiment. On one session they experienced an emotion induction (being randomly assigned to either disgust, negative or positive groups) and on the other they received a neutral control induction. Before and after each induction, and at 15 and 30min post-induction, participants engaged in a cold-pressor task, rating pain intensity at 10s intervals for 90s on each occasion. Relative to neutral control and pre-test, average pain intensity decreased then increased across time following the disgust induction, with the reverse pattern in the negative and positive emotion inductions. These findings are the first to suggest that disgust may lead to an increase in pain sensitivity over a time course paralleling changes observed for core-body temperature and immune-related function, although the mechanisms underpinning these effects remain to be identified.

Is disgust prepared? A preliminary examination in young children.

Children may be prepared to associate adult disgust reactions with adult disgust elicitors. To test this, three-year olds (and adults) were presented with two images and an emotive vocalization. The images and vocalizations included stimuli adults found disgusting, fear-provoking, and sad. On one set of trials, the main dependent variable (DV) was time spent looking at each image and on a second set of repeat trials the DV was knowledge of image-sound matches. Fear and disgust vocalizations were both more effective at orienting a child's attention to adult fear and disgust images, than sad vocalizations. Parental disgust sensitivity was associated with this effect, moderated by explicit matching knowledge. Matching knowledge was poor in children and good in adults. These data suggest that in children, fear and disgust vocalizations may both promote attention to stimuli that adults find disgusting and/or fear-provoking, suggesting that "preparedness" may not be wholly emotion-specific.

Disgust elevates core body temperature and up-regulates certain oral immune markers.

Recent findings suggest that disgust can activate particular aspects of the immune system. In this study we examine whether disgust can also elevate core body temperature (BT), a further feature of an immune response to disease. In addition, we also examined whether food based disgust--a core eliciting stimulus--may be a more potent immune stimulus than non-food based disgust. Healthy males were randomly assigned to view one of four sets of images--food disgust, non-food disgust, food control and negative emotion control. Measures of BT, salivary immune and related markers, and self-report data, were collected before, and at two time points after image viewing. Disgust elevated BT relative to the negative emotion control condition, as did food images. Different mechanisms appeared to account for these effects on BT, with higher initial levels of Tumor Necrosis Factor alpha (TNF-a) and disgust, predictive of BT increases in the disgust conditions. Disgust also increased TNF-a, and albumin levels, relative to the control conditions. Type of disgust exerted little effect. These findings further support the idea that disgust impacts upon immune function, and that disgust serves primarily a disease avoidance function.

Disease-avoidant behaviour and its consequences.

Medical conditions that are non-contagious, but that appear contagious, seem to result in the sufferer being avoided. Error management theory (EMT), suggests that such false alarms occur because the cost of infection poses a greater threat to ones fitness than avoidance. Study 1 attempted to demonstrate a disease-related false alarm effect by asking participants, to evaluate a series of vignettes, featuring people with infectious diseases, non-infectious diseases that looked infectious and non-infectious diseases that did not. Judgements of contracting infection under varying levels of contact, and desire to avoid were obtained. Consistent with EMT, a false alarm effect was evident. Study 2 examined the importance of the face as a key indicator of real and apparent infection, by determining whether facial symptoms result in a greater desire to avoid people with infectious and non-infectious diseases. Consistent with expectation, participants reported a greater desire to avoid people with facially displayed symptoms. Together, these results support the idea that humans have evolved a general tendency to avoid individuals with disease signs, especially if displayed upon the face. One consequence is that where a facially displayed disease sign persists, even if known to be benign, its bearer will experience chronic avoidance.

Proactive strategies to avoid infectious disease.

Infectious disease exerts a large selective pressure on all organisms. One response to this has been for animals to evolve energetically costly immune systems to counter infection, while another--the focus of this theme issue--has been the evolution of proactive strategies primarily to avoid infection. These strategies can be grouped into three types, all of which demonstrate varying levels of interaction with the immune system. The first concerns maternal strategies that function to promote the immunocompetence of their offspring. The second type of strategy influences mate selection, guiding the selection of a healthy mate and one who differs maximally from the self in their complement of antigen-coding genes. The third strategy involves two classes of behaviour. One relates to the capacity of the organisms to learn associations between cues indicative of pathogen threat and immune responses. The other relates to prevention and even treatment of infection through behaviours such as avoidance, grooming, quarantine, medicine and care of the sick. In humans, disease avoidance is based upon cognition and especially the emotion of disgust. Human disease avoidance is not without its costs. There is a propensity to reject healthy individuals who just appear sick--stigmatization--and the system may malfunction, resulting in various forms of psychopathology. Pathogen threat also appears to have been a highly significant and unrecognized force in shaping human culture so as to minimize infection threats. This cultural shaping process--moralization--can be co-opted to promote human health.

Disease avoidance as a functional basis for stigmatization.

Stigmatization is characterized by chronic social and physical avoidance of a person(s) by other people. Infectious disease may produce an apparently similar form of isolation-disease avoidance-but on symptom remission this often abates. We propose that many forms of stigmatization reflect the activation of this disease-avoidance system, which is prone to respond to visible signs and labels that connote disease, irrespective of their accuracy. A model of this system is presented, which includes an emotional component, whereby visible disease cues directly activate disgust and contamination, motivating avoidance, and a cognitive component, whereby disease labels bring to mind disease cues, indirectly activating disgust and contamination. The unique predictions of this model are then examined, notably that people who are stigmatized evoke disgust and are contaminating. That animals too show avoidance of diseased conspecifics, and that disease-related stigma targets are avoided in most cultures, also supports this evolutionary account. The more general implications of this approach are then examined, notably how it can be used to good (e.g. improving hygiene) or bad (e.g. racial vilification) ends, by yoking particular labels with cues that connote disease and disgust. This broadening of the model allows for stigmatization of groups with little apparent connection to disease.

The effect of disgust on oral immune function.

Disgust motivates avoidance of pathogen sources, but whether its role in disease avoidance extends into activating the immune system is unexplored. This was tested here by comparing oral immune markers before and after a disgust induction, relative to neutral and negative induction control groups. The disgust group, but not controls, revealed an oral inflammatory response, with increased salivary tumor necrotizing factor alpha and albumin, as well as a down-regulation of immunoglobulin A (SIgA) secretion. It has been hypothesized that disgust evolved in animals to clear toxins from the oral cavity by gaping and increased salivary flow. Our data suggest down-regulated SIgA secretion may be a vestige of this response so as to conserve protein, while the inflammatory reaction may reflect an adaptive response to disease threat, selectively triggered by disgust. The broader implications of these data for a discrete neuro-gut-immune axis are examined.

Effect of self-reported sexual arousal on responses to sex-related and non-sex-related disgust cues.

Prior to and during sexual intercourse, people are exposed to stimuli that in other contexts might act as disgust-eliciting cues. This study examined whether sexual arousal, in contrast to general arousal, could selectively reduce reported disgust for cues that pilot participants identified as sex or non-sex related. Male undergraduates were randomly assigned to one of four viewing groups. One group viewed erotic female images, a second clad female images, a third pleasantly arousing images (e.g., skydiving), and a fourth unpleasantly arousing images (e.g., an aimed gun). After the viewing phase, all participants were exposed to pairs of real disgust elicitors (sex versus non-sex related) drawn from various sensory modalities. Participants in the erotic images group, who rated being more sexually aroused than those in the other three groups, also reported being significantly less disgusted by sex-related elicitors. While the mechanism for this effect is not currently known, our findings suggest one plausible explanation for risky sexual behavior as well as having implications for the role of disgust in sexual dysfunction.

Children's response to adult disgust elicitors: development and acquisition.

Little is known about when or how different disgust elicitors are acquired. In Study 1, parents of children (0-18 years old) rated how their child would react to 22 disgust elicitors. Different developmental patterns were identified for core, animal, and sociomoral elicitors, with core elicitors emerging first. In Study 2, children (2-16 years old) were exposed alone and then with their parent to a range of elicitors derived from Study 1. Self-report, behavioral, and facial expression data were obtained along with measures of contagion, conservation, and contamination. Convergent evidence supported the developmental patterns reported in Study 1. Evidence for parent-child transmission was also observed, with parents of young children emoting more disgust to their offspring and showing greater behavioral avoidance. Moreover, child reactivity to animal and sociomoral elicitors and contamination correlated with parental responsiveness. Finally, young children who failed to demonstrate contagion and conservation knowledge were as reactive to core elicitors and contamination as children of the same age who demonstrated such knowledge. These findings are interpreted within an evolutionary framework in which core disgust responses are acquired early to promote avoidance of pathogens.

A scale for measuring hygiene behavior: development, reliability and validity.

BACKGROUND: There is currently no general self-report measure for assessing hygiene behavior. This article details the development and testing of such a measure. METHODS: In studies 1 to 4, a total of 855 participants were used for scale and subscale development and for reliability and validity testing. The latter involved establishing the relationships between self-reported hygiene behavior and existing measures, hand hygiene behavior, illness rates, and a physiological marker of immune function. In study 5, a total of 507 participants were used to assess the psychometric properties of the final revised version of the scale. RESULTS: The final 23-item scale comprised 5 subscales: general, household, food-related, handwashing technique, and personal hygiene. Studies 1 to 4 confirmed the scale's reliability and validity, and study 5 confirmed the scale's 5-factor structure. CONCLUSIONS: The scale is potentially suitable for multiple uses, in various settings, and for experimental and correlational approaches.