Digits Of Right Hand Research Articles

Salvage of thumb in a crush injury by a groin flap

The primary function of the hand and fingers is to grasp or manipulate objects of any size or shape with fine touch, strength and the required amount of pressure. The thumb plays a crucial role as unlike other fingers it can work opposite of all digits and carry functions like pinching and grasping, which most of the human activities are dependent on. Crush Injuries of the hand can be severe which can lead to amputation of the digits. Hereby discussing a case of 54-year-old gentleman who met with a road traffic accident with resultant crush injury to the right hand and thumb managed by microsurgery using a groin flap reconstruction of the thumb followed by skeletal stabilization of right-hand digits. The following case report is a concise approach to manage a crush injury with restoration of maximal function of the thumb using a groin flap.

Does maturity estimation, 2D:4D and training load measures explain physical fitness changes of youth football players?

ObjectivesThe purpose of the present study was two-fold: (1) To analyse physical fitness changes of youth football players after a full-season; and (2) to examine whether physical fitness changes are explainable by estimated maturity status, 2digit:4digit ratio (2D:4D) from each hand and training load (TL) measures.MethodsTwenty-seven youth elite Under-15 football players were daily monitored for training load measures during 38 weeks. At the beginning and at the end of the season, all players were assessed for physical fitness. Also, the maturity status estimation and the length of the second and fourth digits of both hands were collected at the beginning of the season.ResultsSignificant differences were found for all physical fitness measures after the season. The second and fourth digits of left and right hands had negative moderate correlations with change of direction (COD) changes (r=-.39 to − 0.45 | p = .05 to 0.02). Also, the maturity offset measure had negative moderate correlations with COD changes (r=-.40 | p = .04). From the reported significant correlations, the maturity offset, Left 4D, Right 2D and Right 4D significantly predicted the Mod.505 COD test changes (β = 0.41, p = .04; β = -0.41, p = .04; β = -0.45, p = .02; and β = -0.44, p = .03, respectively).ConclusionThe maturity offset and the 2D:4D measures have the potential to predict COD performance changes over-time in youth football players. Given the lack of associations between the maturity estimation, 2D:4D and training load measures, with the overall physical fitness measures, coaches should rely only at COD changes.

Maternal Age and Behavior during Pregnancy Affect the 2D:4D Digit Ratio in Polish Children Aged 6-13 Years.

Simple SummaryThe digit ratio (2D:4D) is a marker of prenatal exposure to sex hormones. It is also correlated with many somatic, cognitive, and behavioral traits. The current study examined whether maternal age, health, and lifestyle during pregnancy affect 2D:4D in school-age children of both sexes. The material consisted of digit measurements and questionnaire results for 1219 children (573 boys and 646 girls) aged 6–13 years. The right hand digit ratio in both boys and girls was found to be positively correlated with maternal smoking and negatively with maternal work during pregnancy. Maternal age at childbirth was negatively related to right hand 2D:4D, but only in daughters. These findings suggest that the digit ratio in offspring may be correlated not only with prenatal sex hormone levels, but also with 2D:4D heritability associated with maternal behavior.Background: The length of the second and fourth finger calculated as a ratio (2D:4D) is a marker of prenatal exposure to sex hormones. Higher exposure to testosterone is related to a lower 2D:4D digit ratio, and inversely, higher exposure to estrogen is related to a higher 2D:4D. The digit ratio in humans (prenatally determined by sex hormone levels and androgen receptor activity) is associated with multiple biological, cognitive, and behavioral traits, as well as health in later life. The aim of this study was to verify if maternal traits during pregnancy are associated with 2D:4D among their children. Methods: We investigated 537 boys, 646 girls, and their mothers. The investigation consisted of a questionnaire and a measurement part. In the questionnaire, we included questions about maternal traits during pregnancy such as: illnesses, active and passive smoking, work activity, psychological trauma (death or serious illness of a loved one, divorce, job loss), and age. We performed length measurements of the second and fourth fingers on both hands for both study groups. Results: The GLM analysis showed that children of smoking mothers were characterized by a higher 2D:4D R as compared to their peers whose mothers did not smoke (β = 0.10, p = 0.0008). In turn, the offspring of women who worked during pregnancy exhibited lower 2D:4D R values than the children of women who did not work (β = −0.07, p = 0.0233). It should be noted, however, that the effects of those maternal factors were small, as each of them explained less than 1% of 2D:4D R in the population, adjusted for child age and sex. Pearson’s linear correlation revealed that maternal age was negatively correlated with 2D:4D R in daughters (r = −0.11, p = 0.0137), but not in sons (r = 0.02, p = 0.6908). The negative correlation of 2D:4D R with maternal age indicates that the daughters of older mothers exhibited lower values of that ratio relative to the same-age daughters of younger mothers. Conclusions: For both study groups, the right-hand digit ratio was positively correlated with maternal smoking and negatively with maternal work during pregnancy. Maternal age during pregnancy was negatively related to right hand 2D:4D only among girls.

Influence of gonadal steroids on cortical surface area in infancy.

Sex differences in the human brain emerge as early as mid-gestation and have been linked to sex hormones, particularly testosterone. Here, we analyzed the influence of markers of early sex hormone exposure (polygenic risk score (PRS) for testosterone, salivary testosterone, number of CAG repeats, digit ratios, and PRS for estradiol) on the growth pattern of cortical surface area in a longitudinal cohort of 722 infants. We found PRS for testosterone and right-hand digit ratio to be significantly associated with surface area, but only in females. PRS for testosterone at the most stringent P value threshold was positively associated with surface area development over time. Higher right-hand digit ratio, which is indicative of low prenatal testosterone levels, was negatively related to surface area in females. The current work suggests that variation in testosterone levels during both the prenatal and postnatal period may contribute to cortical surface area development in female infants.

Differences in digit ratios between gay men who prefer receptive versus insertive sex roles indicate a role for prenatal androgen

Among non-human mammals, exposure to androgens during critical periods of development leads to gynephilia (attraction to females), whereas the absence or low levels of prenatal androgens leads to androphilia (attraction to males). However, in humans, retrospective markers of prenatal androgens have only been associated with gynephilia among women, but not with androphilia among men. Here, we asked whether an indirect indication of prenatal androgen exposure, 2D:4D, differs between subsets of gay men delineated by anal sex role (ASR). ASR was used as a proxy for subgroups because ASR groups tend to differ in other measures affected by brain sexual differentiation, such as gender conformity. First, we replicated the finding that gay men with a receptive ASR preference (bottoms) report greater gender nonconformity (GNC) compared to gay men with an insertive ASR preference (tops). We then found that Tops have a lower (male-typical) average right-hand digit ratio than Bottoms, and that among all gay men the right-hand 2D:4D correlated with GNC, indicating that a higher (female-typical) 2D:4D is associated with increased GNC. Differences were found between non-exclusive and exclusive same-sex attraction and GNC, and ASR group differences on digit ratios do not reach significance when all non-heterosexual men are included in the analyses, suggesting greater heterogeneity in the development of non-exclusive same-sex sexual orientations. Overall, results support a role for prenatal androgens, as approximated by digit ratios, in influencing the sexual orientation and GNC of a subset of gay men.

Digit ratio, a proposed marker of the prenatal hormone environment, is not associated with prenatal sex steroids, anogenital distance, or gender-typed play behavior in preschool age children.

Prenatal hormones have been proposed as key factors impacting child development as well as long-term health and disease. Digit ratio (the ratio of the lengths of the second to fourth digits; 2D:4D) has been proposed as a sexually dimorphic, noninvasive marker of prenatal androgen exposure that can be reliably measured in children and adults. To date, few longitudinal pregnancy cohort studies have examined childhood digit ratio in relation to other relevant measures including prenatal hormones and androgen-sensitive outcomes. To augment the current literature on this topic, we measured right-hand digit ratio in 4-year-old children participating in The Infant Development and the Environment Study, a multicenter longitudinal cohort study that has been following mother-child dyads since the first trimester of pregnancy (n = 321). We assessed sex differences in digit ratio and fit multivariable linear regression models to examine digit ratio in relation to: (1) child sex; (2) maternal sex steroid hormone concentrations in early pregnancy; (3) newborn anogenital distance, another proposed measure of sensitivity to prenatal androgens; and (4) gender-typical play behavior as measured by the Preschool Activities Inventory (PSAI) at age 4. We observed no sex difference in digit ratio; the mean 2D:4D was 0.97 ± 0.05 mm in both sexes. Furthermore, digit ratio was not associated with maternal sex steroid concentrations in early pregnancy, anogenital distance in either sex, or PSAI scores in either sex in covariate-adjusted models. In conclusion, we observed no evidence that early childhood digit ratio was associated with child sex or hormone-sensitive measures in this cohort.

Fluctuating asymmetry of finger lengths, digit ratio (2D:4D), and tattoos: A pre-registered replication and extension of Koziel et al. (2010)

BackgroundTattoos bring risks yet no obvious evolutionary benefit. Koziel et al. (2010) reported increased fluctuating symmetry (a proxy for low developmental instability) in tattooed men, suggesting they could serve as fitness indicators. AimsWe replicate and extend the findings of Koziel et al. by examining fluctuating asymmetry of finger lengths and digit ratio (2D:4D) (a putative indicator of prenatal testosterone exposure) as predictors of adult tattoo prevalence. Study designWe used an online survey with a correlational design. SubjectsParticipants were recruited from the UK and Poland via university participant pools and social media. Data were available for presence/absence of tattoos and at least one predictor variable (composite Fluctuating Asymmetry [cFA], right-hand digit ratio [R2D:4D] and left-hand digit ratio [L2D:4D]) for n = 186 males and n = 997 females. Outcome measuresWe firstly assessed presence/absence of tattoos; when at least one tattoo was present, we also examined overall number and highest visibility. ResultsGreater cFA was associated with lower likelihood of having tattoos in males, though in females greater cFA was associated with higher numbers of tattoos. R2D:4D and L2D:4D correlated negatively with number of tattoos in males, and a positive correlation between L2D:4D and number of tattoos was observed in females. However, these latter findings did not remain significant after controlling for covariates. ConclusionsTattoos may act as fitness indicators in males, though this explanation appears not to extend to females. Prenatal testosterone may also play a role, though doubt is cast on this premise because 2D:4D effects did not remain statistically significant after controlling for covariates.

Digit ratio as a risk factor for muscle dysfunction and acute exacerbation in patients with chronic obstructive pulmonary disease.

ObjectiveThis study investigated the correlations of digit ratio (relative length of second and fourth fingers, 2D: 4D) and muscular strength with the progression of chronic obstructive pulmonary disease (COPD).MethodsIn total, 164 patients with COPD were enrolled in this prospective study. In all patients, the following parameters were measured: body compartments, pulmonary function, digit ratio (i.e., 2D: 4D), muscle function, and levels of partial pressure of oxygen and partial pressure of carbon dioxide in arterial blood.ResultsThe right-hand digit ratio (R2D: 4D) was associated with dominant hand muscle dysfunction, non-dominant hand muscle dysfunction, and inspiratory muscle dysfunction. Logistic regression analysis showed that right-hand 2D: 4D (odds ratio [OR] = 0.01) and dominant hand muscle dysfunction (OR = 5.60) were significantly associated with past hospital admission. After adjustment for forced expiratory volume in 1 second, the following factors were associated with present acute exacerbations: right-hand 2D: 4D (OR = 0.01), dominant hand muscle dysfunction (OR = 3.83), expiratory muscle dysfunction (OR = 3.80), and inspiratory muscle dysfunction (OR = 3.61).ConclusionsLower digit ratio may be associated with higher prevalence of muscle dysfunction. This factor could be used to identify patients with COPD who are at higher risk of acute exacerbation.

Early life conditions and adolescent sexual orientation: A prospective birth cohort study.

This study tested the association between multiple prenatal and postnatal early life factors and adolescent sexual orientation in a longitudinal birth cohort. Factors included birth weight, gestational age, parental age at birth, number of older brothers and sisters, breastfeeding, maternal anxiety/depression, family socioeconomic position, parent-child relationships, parental absences, pubertal body mass index, and housing issues. We used data on 5,007 youth from the Avon Longitudinal Study of Parents and Children (ALSPAC). Sexual orientation was assessed using a 5-point scale of sexual attraction at 15.5 years. Early life factors were separated into three developmental periods: prenatal (n = 9), before 7 years (n = 5), and after 7 years (n = 5). We controlled for childhood gender nonconformity, handedness, and digit ratio as markers of prenatal androgen exposure. Gender nonconformity was strongly associated with later male and female nonheterosexuality, and higher right-hand digit ratio was associated with later male nonheterosexuality. Boys with low birth weight and shorter breastfeeding duration were more likely to have a later nonheterosexual orientation. Boys with parental absence before 7 years of age were more likely to be nonheterosexual, but this effect disappeared after entering all early life history factors. Parental absence since birth, low prenatal family socioeconomic position, and poorer parent-child relationship were associated with later nonheterosexuality among girls. The results are discussed in the context of a life history framework for understanding human sexual orientation development in males and females. (PsycINFO Database Record (c) 2019 APA, all rights reserved).

Second to fourth digit ratio and lung function (forced vital capacity): predictors of maximum urinary flow rate after holmium laser enucleation of the prostate.

Maximum urinary flow rate (Qmax) is usually increased after holmium laser enucleation of the prostate (HoLEP). However, improvements vary between patients and results regarding potential predictors of Qmax after HoLEP are inconsistent. Thus, we investigated pre-operative variables including second to fourth digit ratio (digit ratio) and pulmonary function test (PFT) findings as potential predictors of Qmax after HoLEP. One hundred and ninety-five consecutive patients with benign prostatic hyperplasia (BPH) who underwent HoLEP were enrolled. Before HoLEP, PFTs were performed and lengths of second and fourth digits of right hands were measured by a single investigator using a digital vernier caliper. To identify independent predictors of Qmax after HoLEP, univariate and multivariate analyses were performed using linear regression models. Mean age and total prostate volume for all 195 study subjects were 69.4years and 63.3 mL respectively. Mean pre-operative and post-operative Qmax values were 8.7 and 26.2 mL/sec respectively. Univariate analysis showed age (r=-0.181, p=0.014), digit ratio (r=0.213, p=0.004), lung function (forced vital capacity (FVC): r=0.218, p=0.005; forced expiratory volume in 1sec (FEV1): r=0.166, p=0.034), pre-operative Qmax (r=0.264, p=0.000), pre-operative voided volume (VV) (r=0.158, p=0.033), and post-operative VV (r=0.311, p=0.000) were associated with post-operative Qmax, whereas multivariate analysis showed that digit ratio (β=0.285, p=0.001), FVC (β=0.340, p=0.039), and post-operative VV (β=0.301, p=0.000) independently predicted post-operative Qmax. The independent predictors of Qmax after HoLEP were digit ratio and lung function (FVC) as well as post-operative VV. This means that the higher a man's digit ratio and lung function (FVC), the higher his Qmax after HoLEP.

The presence of synchronized perfusion dips in the microcirculation of the resting nail bed

ObjectivesLaser speckle contrast imaging (LSCI) has seen limited use in the study of perfusion dynamics such as vasomotion. The aim of this study was to investigate the effects of a prolonged seated position on perfusion dynamics in the nail bed using LSCI. MethodsPerfusion was recorded in digits II to IV bilaterally for 20 min during two separate sessions in ten healthy volunteers. The acclimatization period was 5 min for the 1st session and 20 min for the 2nd. Perfusion variability and the presence of recurring perfusion dips were analyzed. A digital nerve block was done to verify suspected nervous origin of phenomenon. ResultsSynchronized phases of vasoconstriction were observed in all subjects with perfusion dips in all digits bilaterally and simultaneously. Application of a digital nerve block abolished perfusion dips. The frequency of this phenomenon increased by 25.0% (95% CI: 1.6 to 49.2%) in the left-hand digits after a prolonged seated position. Perfusion variability increased by 11.6% (95% CI: 2.6 to 20.3%) in the digits of the left hand. Perfusion changes in right-hand digits did not significantly increase. During the 1st session, temperature increased by 2.7 °C (1.1 to 4.2) while it decreased by 1.3 °C (0.2 to 2.4) during the 2nd session. ConclusionThe observed perfusion dips are of a centrally mediated nervous origin but are also affected by local factors. They are affected by seating duration and differ between left and right hands, likely because of local micro perfusion dips. This phenomenon seems related to digital thermoregulation.

Detection of severe digital vasculopathy in systemic sclerosis by colour Doppler sonography is associated with digital ulcers.

Colour Doppler ultrasonography (CDUS) is very important in general vascular diagnostic procedures. Its role in determining the extent of vasculopathy in Systemic Sclerosis (SSc) needs further investigation. The aim of this study was to compare the presence of altered arteries with nailfold capillaroscopy and clinical signs of ischaemia, that is, digital ulcers or pitting scars (DU/PS). A feasible CDUS protocol is provided. Two thousand five hundred and twenty-eight arteries of the fingers, palms and wrists from 79 SSc patients (32 arteries per patient) were examined using CDUS. Furthermore, nailfold capillaroscopy, clinical and laboratory data were evaluated. Narrowed or occluded lumens were seen in 39.8% of all assessable arteries (n = 2489) and 48.9% of all proper palmar digital arteries (n = 1564) but only 15.6% (P < 0.0001) of proximal arteries (n = 924). Fingerwise analyses presented significant coincidence of pathological CDUS findings and DU/PS (P = 0.0009). Pathological CDUS findings were also associated with elevated CRP concentrations, current or past smoking with ⩾20 pack-years, male gender and present or past DU/PS. Receiver operating characteristic curve analysis (area under the curve = 0.727) suggested a cut-off value of ⩾20% pathological vessels (sensitivity: 90.7%; specificity: 47.8%) for the presence of DU/PS. An examination protocol focusing on the right-hand digits II-V (proper palmar digital arteries) revealed similar results (area under the curve = 0.751; sensitivity: 93.0%; specificity: 43.5%). CDUS of hand and finger arteries allows measurement of the extent of SSc vasculopathy, which is associated with clinical signs of chronic malperfusion. A shortened examination protocol of CDUS (right-hand digits II-V; 15 min instead of 45 min examination time) could complement vascular diagnostics in SSc.

Why Does Digit Ratio Research Fail to Give Any Implication Regarding the Organizational Effect of Prenatal Androgen?

Abstract. The digit ratio is a putative biomarker for evaluating the organizational effects of prenatal testosterone. This evaluation was performed by relating postnatal traits to digit ratio. We examined the relationship among digit ratio, depression, and positive/negative affect. A total of 335 university students who completed a set of questionnaires had both of their hands scanned, and the digit ratios were measured using a computer program. All the studied variables were insignificantly related to the right-hand digit ratio. The variables remained insignificant even when the data for males and females were analyzed separately. Furthermore, a meta-analysis, including a previous study combined with current data, showed no association between digit ratio and depression, although the current sample size of 355 could detect r = 0.2 at α = 0.05, and β = 0.2. The lack of association between digit ratio and depression was common, and the present results corroborated those of previous studies, which showed no association between digit ratio and depression. This nil result would be least likely attributable to an inadequate sample size, considering that the current sample size of 335 allowed the detection of r = 0.2 at α = 0.05 and β = 0.2, nor idiosyncratic results, given that the meta-analysis with previous relevant studies also concluded the same results. We extensively reviewed the relevant literature and evaluated the use of digit ratio as a biomarker for prenatal testosterone exposure in seven different perspectives. Nearly all the analysis showed the problems of using digit ratio as a biomarker for evaluating the organizational effect of prenatal hormones.

The culture of honor as the best explanation for the high rates of criminal homicide in Pernambuco: A comparative study with 160 convicts and non-convicts

The present work aimed to investigate the propensity towards criminal homicide using a broad approach, encompassing theories based on socioeconomic frustration, decision-making processes, emotional attachment, testosterone, moral development, moral values, and the culture of honor. A total of 160 adult Brazilian men completed a questionnaire, various psychological tests, and right-hand digit ratio measurements. The findings discarded all theories tested, except the culture of honor. It is concluded that, in the region, public policies for the reduction of the rate of homicides must be specific to that crime and address cultural issues regarding honor and moral satisfaction.

Individual fMRI maps of all phalanges and digit bases of all fingers in human primary somatosensory cortex.

This study determined the individual maps of all fingers in Brodmann area 3b of the human primary somatosensory cortex in a single fMRI session by tactile stimulation at 19 sites across all phalanges and digit bases of the 5 right-hand digits. To quantify basic features of the digit maps within and across subjects, we applied standard descriptive measures, but also implemented a novel quantitative analysis. This so-called Direction/Order (DiOr) method tested whether subjects exhibited an ordering of peak fMRI representations along their individual direction of alignment through the set of analyzed phalanges and whether these individual directions were similar across subjects. Across-digit analysis demonstrated that for each set of homologous phalanges, the D5-to-D1 representations were successively represented along a common direction of alignment. Hence, the well-known mediolateral D5-to-D1 somatotopy was not only confirmed for the distal phalanges (p1), but could also be shown for the medial (p2) and proximal phalanges (p3). In contrast, the peak activation for the digit bases (p4) only partly elicited that digit succession. Complementary, intra-digit analysis revealed a divergent picture of map topography for the different digits. Within D5 (and in a trend: D4), an ordered p1-to-p3 succession was found across subjects, pointing to a consistent intra-digit somatotopy for D5, with p3 generally found medial-posterior to p1. In contrast, for D1, D2, and D3, most subjects did not present with ordered p1-to-p3 maps nor were directions of alignment similarly oriented between subjects. These digits therefore exhibited highly diverse representation patterns across subjects.

Association of Height and Weight with Second to Fourth Digit Ratio (2D:4D) and Sex Differences

Sex difference in 2D:46 digit ratio was studied in 386 right-handed students. The lengths of index (2D) and ring (4D) fingers were measured using a caliper. Height and weight of participants were recorded. Body height correlated negatively with right- and left-hand digit ratios in the total sample (N = 386); correlations were significant for the left-hand digit ratio of men and for the right-hand digit ratio of women (no significant correlations with weight). Males had a significantly lower 2D:4D ratio than females. After controlling for height, sex differences in right- and left-hand digit ratios completely disappeared. The results suggest that height of adults reflecting prenatal hormone status may play a role in differences between men and women in 2D:4D digit ratio for right-handers.

Masculinized finger-length ratios of boys, but not girls, are associated with attention-deficit/hyperactivity disorder.

Gonadal hormones may exert permanent organizational effects on sexually dimorphic finger-length ratios and sexually dimorphic behavior expressed in childhood attention deficit-hyperactivity disorder (ADHD). This study extended recent work examining associations between finger-length ratios (specifically, 2D:4D) and ADHD in a well-characterized, clinically diagnosed, community-recruited sample of boys and girls. A multistage, diagnostic procedure was utilized to identify 113 children with ADHD and 137 non-ADHD comparison children. Right-hand digit ratios showed significant mean differences by gender, as well as associations with ADHD diagnosis. Boys with ADHD had more masculinized digit ratios than control-group boys. More masculine right 2D:4D and 3D:4D ratios were correlated with parent- and teacher-rated inattentive and hyperactive-impulsive symptoms in boys but not in girls. Masculinized finger-length ratios were associated with hyperactive-impulsive and oppositional- defiant symptoms, but associations were largest with symptoms of inattention. It is concluded that prenatal, organizational effects of gonadal hormones may play a role in the development of ADHD and contribute to explaining sex differences in the prevalence rates of this childhood disorder.

Tourniquet-associated cardiac ischaemia in a healthy patient undergoing trauma hand surgery

EDITOR: Surgical tourniquet use is commonplace in orthopaedic, plastic and trauma theatres. Complications are well recognized. Here we describe an unusual and previously undescribed complication during hand surgery on a fit, healthy young male. Case report A 25-yr-old male smoker (10 cigarettes per day) with no previous medical history and muscular body habitus underwent tendon and nerve repairs of his fourth and fifth right-hand digits following an accident with a knife. The patient was fasted and anaesthesia was induced with propofol, midazolam and fentanyl. A size 4 disposable laryngeal mask was inserted and anaesthesia maintained with isoflurane and nitrous oxide. Intravenous (i.v.) morphine was given (total of 10 mg over 4 h) along with diclofenac (75 mg) and paracetamol (1 g). The patient received 2 L of Hartmann's solution during the first 3 h in theatre. The tourniquet was deflated after 2 h at 250 mmHg. This coincided with a rise in end-tidal CO2 and then, around 20 min following tourniquet deflation, ST segment depression was clearly noted on the ECG tracing in leads II and III. This progressed over the final hour of the operation such that gross ST segment depression was noted (up to 7.5 mm) in leads I, II and III and was associated with relative hypotension (mean arterial pressure (MAP) falling from around 70 to 55 mmHg). This was refractory to a further 1 L of Hartmann's solution and 1.5 L of Gelofusine. Ventilation was continued with oxygen and isoflurane at the onset of ST depression. The patient was catheterized and a temperature probe was inserted (patient was normothermic throughout). On chest auscultation, air entry was equal bilaterally and breath sounds vesicular. I.V. nitrates were commenced cautiously (approximately 0.3 μg kg−1 min−1) with no further drop in MAP and slight improvement in the electrocardiogram (ECG). Blood samples were sent for full blood count, urea and electrolytes. The patient was taken to theatre recovery for 12 lead ECG and further management. In recovery, a 12 lead ECG confirmed global ST segment depression, and a cardiological opinion was sought. An echocardiogram was unremarkable and showed good left ventricular systolic function. The patient awoke not complaining of any symptoms and the ECG signs completely resolved within 20 min of leaving theatre. An arterial blood gas sample taken immediately in theatre recovery showed a metabolic acidosis (pH 7.30, base deficit 7), and electrolytes revealed serum potassium of 5.9 mmol L−1. The patient left theatre recovery 3 h postoperatively, with a completely normal ECG and repeat bloods, which showed resolution of the previous discrepancies. The patient made a full recovery and was discharged home 2 days later. Discussion The timing of these events, the biochemical findings and, perhaps, the patient's muscular body habitus, lead us to suggest a cause for this event attributable to the surgical tourniquet. We hypothesize that a relatively long tourniquet time and its placement on the muscular arm of our patient led to muscle ischaemia with accumulation and release of lactate and intracellular mediators following tourniquet deflation. The onset of signs around 20 min following deflation coupled with the raised serum potassium and metabolic acidosis support this idea. These circulating mediators can be implicated in causing a degree of coronary vasospasm sufficient to produce the noted ECG appearances, but also explain the relatively rapid resolution of the problem. Literature review reveals studies that support our hypothesis of metabolic and haemodynamic insult associated with prolonged tourniquet inflation [1,2]. In addition, there are reports in the literature of vasospasm involving the limb on which the tourniquet had been placed causing ischaemia [3] and a report of acute renal failure secondary to rhabdomyolysis in a fit and muscular young male due to tourniquet application [4]. We are not aware of any reports of cardiac ischaemia, which may likely be attributable to similar mechanisms in our muscular young patient. Although we cannot state with certainty that this was indeed the mechanism of cardiac ischaemia, on ruling out other common intraoperative triggers as possibilities and on reviewing the literature, we feel that this is a plausible and most likely explanation and is of importance and interest to those working with patients using surgical tourniquets. It is difficult to say how our management of a similar case in the future may change with respect to this experience. The tourniquet is required to facilitate good surgical conditions and the procedure was necessarily prolonged. Surgeons, anaesthetists and theatre staff are always attentive to duration of tourniquet use, and it may be impossible to eliminate all associated complications.

Early experience of sex hormones as a predictor of reading, phonology, and auditory perception

Previous research has indicated possible reciprocal connections between phonology and reading, and also connections between aspects of auditory perception and reading. The present study investigates these associations further by examining the potential influence of prenatal androgens using measures of digit ratio (the ratio of the lengths of the index and ring fingers). Those with low digit ratios (shorter index finger and therefore in the masculine direction) are hypothesised to have experienced greater “masculinisation” in the uterus. ANCOVA analyses using a verbal reasoning task as a covariate showed that only phonology was influenced by digit ratio in the right hand indicating that hypothesised androgen effects were inhibiting phonology; however this effect in the left hand was reduced and instead there was an effect indicating an inhibition of androgens on reading. Furthermore, subjects with low right-hand digit ratios were also impaired compared to those with high right-hand digit ratios in an auditory saltation task. These findings are discussed in terms of the possible effects of androgens on early brain development impairing aspects of the temporal processing of sounds by the left hemisphere, which could also have a secondary influence on developing phonology and literacy skills.

The human primary somatosensory cortex response contains components related to stimulus frequency and perception in a frequency discrimination task

Somatosensory stimulation of primary somatosensory cortex (SI) using frequency discrimination offers a direct, well-defined and accessible way of studying cortical decisions at the locus of early input processing. Animal studies have identified and classified the neuronal responses in SI but they have not yet resolved whether during prolonged stimulation the collective SI response just passively reflects the input or actively participates in the comparison and decision processes. This question was investigated using tomographic analysis of single trial magnetoencephalographic data. Four right-handed males participated in a frequency discrimination task to detect changes in the frequency of an electrical stimulus applied to the right-hand digits 2+3+4. The subjects received approximately 600 pairs of stimuli with Stim1 always at 21 Hz, while Stim2 was either 21 Hz (50%) or varied from 22 to 29 Hz in steps of 1 Hz. Both stimuli were 1 s duration, separated by a 1 s interval of no stimulation. The left-SI was the most consistently activated area and showed the first activation peak at 35–48 ms after Stim1 onset and sustained activity during both stimulus periods. During the Stim2 period, we found that the left-SI activation started to differ significantly between two groups of trials (21 versus 26–29 Hz) within the first 100 ms and this difference was sustained and enhanced thereafter (approximately 600 ms). When only correct responses from the above two groups were used, the difference was even higher at later latencies (approximately 650 ms). For one subject who had enough trials of same perception to different input frequencies, e.g. responded 21 Hz to Stim2 at 21 Hz (correct) and 26–29 Hz (error), we found the sustained difference only before 650 ms. Our results suggest that SI is involved with the analysis of an input frequency and related to perception and decision at different latencies.