Does the placement of acetabular cups differ between right and left sides for a right-handed surgeon operating through a direct lateral approach? A comparative study.

PURPOSE: Although many factors were suggested to affect acetabular cup positioning during primary total hip arthroplasty, the effect of surgeon handedness was rarely evaluated. We aimed primarily to assess the difference in cup positioning (inclination and anteversion) between the right and left sides during primary THA. Secondly, to check the difference in the percentages of cups positioned in the safe zone for inclination and anteversion and if there will be a difference in cup positioning according to the type of cup fixation (cemented vs. cementless). METHODS: Cup inclination and anteversion of 420 THAs were radiographically evaluated retrospectively. THAs were performed by a senior right-handed surgeon, who operated through a direct lateral approach in a lateral decubitus position using manual instruments and freehand technique for cup placement. Patients were assigned to two groups: Group A (right, or dominant side), and Group B (left, or non-dominant side), with equal cases of THAs (n = 210) in each group. RESULTS: No difference was found in patients' basic characteristics, preoperative diagnosis, and cup fixation (54.3% cemented and 45.7% cementless) between the two groups. There was a significant difference in cup inclination between Groups A and Group B (40.1° ± 6.3° vs. 38.2° ± 6.1°) (P = 0.002). No significant difference was revealed in anteversion between the two groups (11.7° ± 4.4° vs. 11.8° ± 4.7°) (P = 0.95). The percentage of cups located within the safe zone in terms of both inclination and anteversion was 85.2% vs. 83.8% and 69% vs. 73.3% for Group A and Group B, according to Lewinnek and Callahan's safe zones, respectively. There existed a significant difference in the cemented cup inclination between Group A and Group B (40.8° ± 6.4° vs. 38.3° ± 6.3°) (P = 0.004). CONCLUSION: Cup inclination is affected by the surgeon's handedness when operating through a direct lateral approach and using a freehand technique, while anteversion is less affected. Furthermore, the difference is greater with cemented cups.

The effect of handedness and biological sex on fingermark ridge height and volume as examined by 3D imaging.

For decades, detectives and forensic scientists have relied on friction ridge skin comparisons to identify individuals in criminal investigations. This method involves examining (latent) fingermarks, typically captured as two-dimensional (2D) images, and comparing them with known inked impressions or scans. The comparisons focus on general patterns, the location and orientation of minutiae, and additional characteristics like scars or pores. However, this common process overlooks other potentially valuable factors, such as handedness, biological sex, and the time since deposition, which could provide crucial investigative leads, especially in cases with partial or unclear ridge patterns. This study explored the potential of three-dimensional (3D) optical profilometry (OP) to observe changes in fingermarks ridge height and volume over 7 days while considering hand dominance and biological sex. The results indicated that all the assessed 3D metrics were generally consistent in detecting the effects of sex and handedness, mostly noticeable on aged fingermarks. Specifically, females and impressions from their non-dominant hand exhibited higher values. Additionally, the influence of time was evident, with fresh fingermarks showing significantly larger ridges in terms of height and volume. These findings suggest that 3D OP can enhance the probative value of fingermarks by inferring additional characteristics such as sex, handedness, and the age of the impression. These activity-level propositions could provide useful information in cases where only partial or poor-quality fingermarks are recovered, providing new data dimensions that could lead to more comprehensive forensic examinations.

No Incidental Memory Advantage for Mixed Handed vs. Consistent Right Handed Participants: Conflicting Results From Earlier Research.

Individuals who vary their preferred hand when performing different types of manual activities, so-called mixed handers (MH), have been frequently reported to outperform individuals with a consistent (right) hand preference (cRH) on tasks assessing declarative-memory functions. For example, in one influential study, this MH advantage extended to incidental learning from presumed "deep" semantic processing of verbal stimuli but not from "shallow" phonemic or structural processing. In the present study, we aimed to replicate this research finding in two separate participant samples. First, in a pre-registered and sample-size planned experiment we confronted 49 participants (23 MH; 26 cRH) with "phonemic" and "semantic" word evaluation tasks (using a within design), followed by a surprise delayed recognition test. In a second experiment, we repeated the same procedure with 65 other participants (31 MH, 34 cRH). A mixed-effect analyses of variance found a significant main effect of Encoding Condition (phonemic vs. semantic tasks) in both experiments (effect size: ηp2 = .81 to .85), indicating the classical level-of processing effect with higher recognition hits and sensitivity (d') for words that followed semantic versus phonemic encoding. However, the predicted interaction effect of Encoding Condition with Handedness Group was not statistically significant for either sample (all ηp2 < .03), nor was the main effect of Handedness Group. Thus, our findings conflicted with those of the original study in two independent samples. As we had sufficient statistical power to be confident in our failure to detect a genuine group difference, we cannot confirm the previously reported MH over cRH advantage in incidental learning of verbal material. We discuss possible reasons for these contradictory results and the theoretical implications of this discovery.

Quantifying Hand Motion Complexity in Simulated Sailing Using Inertial Sensors.

The control of hand movement during sailing is important for performance. To quantify the amount of regularity and the unpredictability of hand fluctuations during the task, the mathematical algorithm Approximate Entropy (ApEn) of the hand acceleration can be used. Approximate Entropy is a mathematical algorithm that depends on the combination of two input parameters including (1) the length of the sequences to be compared (m), and (2) the tolerance threshold for accepting similar patterns between two segments (r). The aim of this study is to identify the proper combinations of 'm' and 'r' parameter values for ApEn measurement in the hand movement acceleration data during sailing. Inertial Measurement Units (IMUs) recorded acceleration data for both the mainsail (non-dominant) and tiller (dominant) hands across the X-, Y-, and Z-axes, as well as vector magnitude. ApEn values were computed for 24 parameter combinations, with 'm' ranging from 2 to 5 and 'r' from 0.10 to 0.50. The analysis revealed significant differences in acceleration ApEn regularity between the two hands, particularly along the Z-axis, where the mainsail hand exhibited higher entropy values (p = 0.000673), indicating greater acceleration complexity and unpredictability. In contrast, the tiller hand displayed more stable and predictable acceleration patterns, with lower ApEn values. ANOVA results confirmed that parameter 'm' had a significant effect on acceleration complexity for both hands, highlighting differing motor control demands between the mainsail and tiller hands. These findings demonstrate the utility of IMU sensors and ApEn in detecting nuanced variations in acceleration dynamics during sailing tasks. This research contributes to the understanding of hand-specific acceleration patterns in sailing and provides a foundation for further studies on adaptive sailing techniques and motor control strategies for both novice and expert sailors.

Surgeon handedness affects the acetabular cup positioning during primary total hip arthroplasty regardless of the surgical approach. a systematic review and metanalysis.

PURPOSE: The aim was to investigate the effect of surgeon handedness on acetabular cup positioning, functional outcomes, and dislocation incidence during primary THA. METHODS: A systematic review was conducted according to the PRISMA guidelines. Studies published in English were searched in three databases (PubMed, Embase, and Scopus). A dominant side is a right-handed (RHD) or left-handed (LHD) surgeon who operates on the right or left hip, respectively. The opposite is considered to be the non-dominant side. We used odds ratios for dichotomous data and mean differences for continuous data, with 95% confidence intervals for quantitative data synthesis. Heterogeneity was assessed using the I² test, with outcomes graphically represented in a forest plot and a p-value of < 0.05 considered statistically significant; analyses were performed using Review Manager 5.4 (RevMan 5.4.1). >. RESULT: Four observational studies were included out of 98 articles. Ten experienced surgeons participated (8 RHD and 2 LHD) and operated on 822 patients (1484 hips), divided equally between dominant and non-dominant sides, and the posterolateral approach was utilized in 80.9% of THAs. RHD surgeons operated on 1404 (94.6%) THAs. The pooled synthesis for inclination indicated no significant difference between either side [MD: 0.10 (95% CI -2.10 to 2.30, P = 0.93, I² = 91%)]. While the difference was significant for anteversion [MD: -2.37 (95% CI -3.82 to -0.93, P = 0.001, I² = 31%)]. The functional outcome was better on the dominant side [MD: 1.44 (95% CI 0.41 to 2.48, P = 0.006, I² = 0%)], and the dislocation incidence was significantly higher on the non-dominant side [OR: 0.45 (95% CI 0.25 to 0.81, P = 0.008, I² = 0%)]. CONCLUSION: Surgeon handedness and whether operating on the dominant or non-dominant side could affect the acetabular cup positioning and outcomes during primary THAs, even in the hands of high-volume surgeons.

Evaluating the gonads of left-handed children using ultrasonography and comparing the findings with those of right-handed ones.

Hand use varies according to which brain hemisphere is dominant. Early androgen exposure causes right hemisphere dominance. This study is aimed at comparing the testes and ovary sizes of healthy left-handed girls and boys with those of healthy right-handed children and investigating whether or not lateralization affects the gonads. The ovarian and testicular sizes of healthy left- and right-handed boys and girls who were similar in height, weight, and age were compared by ultrasonography. One hundred and eleven (111) children-including 26 left- and 26 right-handed girls and 31 left- and 28 right-handed boys-were included in this study. The mean age of left-handed girls was 77.2 ± 25.3 months, and the mean age of right-handed girls was 74.4 ± 25.2 months. Right transverse diameter (p = 0.004), right longitudinal diameter (p = 0.009), and right ovarian volume (p = 0.020) were larger in left-handed girls above 8 years of age than in left-handed girls below 8 years of age. However, these values were similar in right-handed girls above and below 8 years of age. In right-handed girls, the transverse diameter was larger in the right ovary than in the left ovary (0.014). Other ovarian values were similar. The mean age of left-handed boys was 85.2 ± 41.3 months, whereas the mean age of right-handed ones was 81 ± 41.2 months. Prepubertal and pubertal right- and left-handed boys had similar mean right and left testicular diameters and volumes (p > 0.05). CONCLUSION: Lateralization affected gonad size in girls. In boys, gonads were not affected by lateralization. Cerebral lateralization may affect the hypothalamic-pituitary-gonadal axis in girls. WHAT IS KNOWN: • Hand use varies according to which cerebral hemisphere is dominant. Males tend to be more left-handed than females. Brain asymmetry can affect the neuroendocrine axis. WHAT IS NEW: • Ultrasonographic gonadal dimensions were examined in left-handed and right-handed children. Cerebral lateralization may affect the hypothalamic-pituitary-gonadal axis in girls.

Where the 'bad' and the 'good' go: A multi-lab direct replication report of Casasanto (2009, Experiment 1).

Casasanto (Journal of Experimental Psychology: General, 138, 351-367, 2009) conceptualised the body-specificity hypothesis by empirically finding that right-handed people tend to associate a positive valence with the right side and a negative valence with the left side, whilst left-handed people tend to associate a positive valence with the left side and negative valence with the right side. Thus, this was the first paper that showed a body-specific space-valence mapping. These highly influential findings led to a substantial body of research and follow-up studies, which could confirm the original findings on a conceptual level. However, direct replications of the original study are scarce. Against this backdrop and given the replication crisis in psychology, we conducted a direct replication of Casasanto's original study with 2,222 participants from 12 countries to examine the aforementioned effects in general and also in a cross-cultural comparison. Our results support Casasanto's findings that right-handed people associate the right side with positivity and the left side with negativity and vice versa for left-handers.

Hemispheric asymmetries in borderline personality disorder: a systematic review.

Borderline personality disorder (BPD) is characterized by increased mood reactivity and affective instability. Since core structures involved in emotion processing, such as the amygdala, demonstrate strong lateralization, BPD is an interesting target for laterality research. So far, a systematic integration of findings on lateralization in BPD is missing. Therefore, we systematically reviewed studies published until February 2024 in PubMed, Web of Science, and PsycInfo databases that measured hemispheric asymmetries and behavioral lateralization in patients with BPD. Inclusion criteria were (a) diagnosis of BPD and (b) results on hemispheric or behavioral asymmetries. Specifically for neuroimaging studies, hemispheres need to be assessed separately. Review articles and studies with disorders other than BPD were excluded. Risk of bias was assessed with the Newcastle Ottawa Scale for non-randomized, non-comparative intervention studies. A total of 21 studies met the inclusion criteria. Thirteen studies investigated structural hemispheric asymmetries, five functional hemispheric asymmetries, two examined handedness, and one studied hemispheric asymmetry in visuospatial attention. Overall, studies examining structural asymmetries in BPD report bilateral volume reduction in the amygdala and hippocampus but a right-sided reduction in the orbitofrontal cortex. For functional lateralization, asymmetrical de/activation patterns in the default mode network in BPD and reduced right-frontal asymmetry were evident. Also, studies indicate a trend towards increased non-right-handedness in BPD. Risk factors for BPD, such as childhood abuse, may play a crucial role in the development of structural and functional alterations. However, the generalization of results may be limited by small sample sizes and varying study designs.

Does the Surgeon's Handedness Affect the Complications Rate in the Inframammary Approach Breast Augmentation?

BACKGROUND: Humans show a preference for left or right handedness in most cases. For this reason, surgeons might find it more difficult to operate on the "nondominant breast", i.e. the breast opposite to the surgeon´s dominant hand (left breast for right-handed surgeons and right breast for left-handed surgeons). The nondominant breast might therefore potentially be prone to a higher complication rate. METHOD: Retrospective data of all consecutive patients who underwent breast augmentations by the first author over the past 15 years was reviewed. In all cases, the entire operation was carried out with the surgeon standing on the right side of the table. All the complications of the right and left breasts were analyzed individually. RESULTS: 1707 patients with a minimum follow-up of six months were reviewed. Mean breast implant volume was 305.6 cc and mean follow-up was 16.12 months. A total of 151 complications were found (8.8%), including rotational deformity, capsular contracture, hematoma, seroma, bottoming out, high riding implant, double bubble deformity, implant rupture and infection. Of these complications, 77 (4.51%) affected the left breast, 48 (2.87%) were found on the right breast and 25 (1.46%) were bilateral. This difference was statistically significant. CONCLUSION: Surgeons´ handedness seem to have an impact on the rate of complications after breast augmentation. As a result of some sort of unease when operating on the nondominant breast, this side might be prone to less precision during the dissection and, consequently, to more complications. Our study found that the rate of complications was higher in the nondominant breast. LEVEL OF EVIDENCE IV: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Inclusion in the clinic: A mixed methods study of left-handed student's perceptions of using cordless keyboards.

PURPOSE/OBJECTIVES: Little is written on obstacles for left-handed students in the dental clinic. This mixed methods study evaluates the experiences of using cordless keyboards for left-handed dental students. METHODS: Researchers purchased four Logitech K400 Plus wireless keyboards. Using Qualtrics, a survey software, a pre-survey was sent out at the beginning of the spring semester prior to introducing the cordless keyboards. A post-survey circulated at the end of the semester. Quantitative analysis statistical analysis was conducted using IBM SPSS Statistics. Researchers conducted a thematic analysis of the qualitative survey responses. RESULTS: Twenty-three left-handed D3 and D4 dental students were asked to participate in a survey about cordless keyboards. The pre-survey had a 100% response rate, and the post-survey had a 71% response rate. The surveys indicated that left-handed students often face a range of barriers in clinical settings, including ergonomic challenges to enter data, difficulty managing time due to double entry of data on right-handed equipment, and feelings of psychological unsafety due to fear for asking for support. The most significant finding was as follows: not only did the cordless keyboard assist clinical performance, but the cordless keyboard project also helped students feel heard and validated as left-handed learners. CONCLUSIONS: Researchers recommend that educators prioritize the inclusion of left-handed learners through various practices like making adjustments to physical spaces and creating inclusive environments where all learners feel supported.

Validation of 3D cryoEM single particle reconstruction correctness and handedness with Ewald's sphere correction.

The correct description of quantum scattering places the observed scattering contributions on the Ewald's sphere and its Friedel mate. In electron microscopy, due to the large radius of the Ewald's sphere, these contributions are typically merged during data analysis. We present an approach that separates and factorizes these contributions into inversion-symmetric and inversion-antisymmetric components. The correlations between reconstructions derived from these symmetric and antisymmetric components enable the automatic determination of handedness and provide additional validation for the quality of 3D reconstructions. These correlations are robust enough to be routinely used in single-particle reconstructions, even at resolutions below the limit where the curvature of the Ewald's sphere affects the overall signal-to-noise ratio.

The influence of the surgeon's handedness and standing position at the operating table on the radiological outcomes in primary total knee arthroplasty.

BACKGROUND: The purpose of this study was to compare radiological outcomes of total knee arthroplasty (TKA) in mechanical alignment implant positioning in the coronal and sagittal planes depending on surgeons' handedness and their position at the operating table. METHODS: A total number of 200 consecutive patients with idiopathic osteoarthritis and varus knees who underwent TKA were retrospectively included in this research. Patients were operated on by 4 surgeons (50 for each surgeon) selected according to their handedness and position at the operative table. Surgeon I (right-handed, standing at the operating table always on the right side); Surgeon II(left-handed, standing at the operating table always on the left side); Surgeon III (right-handed, standing at the operating table on the side of the operated limb); Surgeon IV (left-handed, standing at the operating table on the side of the operated limb). RESULTS: Comparing postoperative radiological results statistically significant differences were calculated in the case of deviation from HKA angle (left TKA -1.5°; Interquartile Range [IQR] = -2.6-[-1] vs right TKA -3°; IQR = -4.5-[-2]; p = 0.01) for surgeon II and MPTA for surgeon IV (left TKA 0°; IQR = -1-0.5 vs right TKA 1°; IQR = 0-2; p < 0.01). Higher deviation from the mechanical alignment angles and implant positioning was revealed for a less convenient operation site for the surgeon. CONCLUSION: We recommend that all surgeons performing TKAs from the less comfortable side should take great care in establishing the MPTA and HKA angles to avoid surgical errors in implant positioning and limb alignment.

Investigating the Correlation between Handedness and Emotion Regulation Strategies in Asthma and Allergy Patients.

Background: Asthma and allergic diseases are common chronic non-communicable conditions that can negatively impact the quality of life of patients. Psychological factors play a role in both the onset and progression of these conditions. The purpose of this study was to examine the relationship between handedness and emotion regulation and cognitive emotion regulation strategies in patients with asthma and allergies in Isfahan, central Iran. Methods: We employed a causal-comparative research design. The study population consisted of all patients visiting Asthma and Allergy Clinic in Isfahan. One hundred participants were selected through probability sampling. Data were collected using the Emotion Regulation Questionnaire and the Cognitive Emotion Regulation Strategies Questionnaire, and were analyzed using univariate analysis of variance (ANOVA). Results: Cognitive emotion regulation was significantly different between right-handed and left-handed patients with asthma and allergies (P=0.0001). A significant difference was also observed between the two groups in their emotion regulation strategies (P=0.031). The rate of positive and negative cognitive regulation strategies was higher in left-handed individuals with asthma and allergies, compared to right-handed individuals. Conclusion: Overall, handedness has a significant impact on the behavior and mental health of patients suffering from asthma and allergies. Therefore, handedness should be taken into consideration in interventions for emotion regulation.

Musicianship and Prominence of Interhemispheric Connectivity Determine Two Different Pathways to Atypical Language Dominance.

During infancy and adolescence, language develops from a predominantly interhemispheric control-through the corpus callosum (CC)-to a predominantly intrahemispheric control, mainly subserved by the left arcuate fasciculus (AF). Using multimodal neuroimaging, we demonstrate that human left-handers (both male and female) with an atypical language lateralization show a rightward participation of language areas from the auditory cortex to the inferior frontal cortex when contrasting speech to tone perception and an enhanced interhemispheric anatomical and functional connectivity. Crucially, musicianship determines two different structural pathways to this outcome. Nonmusicians present a relation between atypical lateralization and intrahemispheric underdevelopment across the anterior AF, hinting at a dysregulation of the ontogenetic shift from an interhemispheric to an intrahemispheric brain. Musicians reveal an alternative pathway related to interhemispheric overdevelopment across the posterior CC and the auditory cortex. We discuss the heterogeneity in reaching atypical language lateralization and the relevance of early musical training in altering the normal development of language cognitive functions.

What does lack of language lateralization signify? Evidence of fluctuating asymmetry rather than hemispheric equipoise on non-lateralized tasks.

In a study of patterns of language laterality in left- and right-handers, Woodhead et al. (Woodhead ZVJ, Thompson PA, Karlsson EM, Bishop DVM. 2021 R. Soc. Open Sci. 8, 200696. (doi:10.1098/rsos.200696)) noted that several tasks showed no bias to the left hemisphere in left-handed individuals. This might appear to suggest that these functions were mediated by the two hemispheres working together equally-what can be termed 'hemispheric equipoise'. Here, I consider an alternative possibility that individuals show lateral bias on these tasks, but the bias can occur to either the left or right-a form of fluctuating asymmetry. Further analysis of the distributions of data from individuals in Woodhead et al. is compared with simulated data. The pattern of results suggests that the impression of hemispheric equipoise may be an artefact of reliance on group data: even though the group mean does not differ from zero, a high proportion of individuals are biased to the left or right.

The Effect of Aerobic Exercise on Visuospatial Attention in Young Adults.

Our objective in this study was to investigate the effect of moderate-intensity aerobic exercise on visuospatial attention bias. We examined line bisection performance at rest before exercise and then immediately after exercise in 20 young adults. Pre-exercise, there was a larger leftward bias in subjective midpoint judgment of all participants than post-exercise (p < .001). Thus, leftward error magnitude decreased according to aerobic exercise, as there were rightward shifts after the exercise. The participants' performancse were modulated by the hand used to perform manual bisection tasks (p < .02). Participants erred to the left of the true midpoint with the non-dominant hand and to the right of the true midpoint with the dominant hand. The use of the non-dominant hand led to greater leftward error than the errors obtained using the dominant hand, though there was no interaction effect between hand use and effort. These findings suggest that moderate aerobic exercise can benefit visuospatial attention in adults.

The "t" time: Investigating handedness through strokes and slopes.

This study investigated the stroke and slope characteristics in left-handed and right-handed handwriting. Stroke (letters t, f, d, and H) and slope (letters t, f, l, d, and g) directions were analyzed on in-house samples (n = 64), revealing statistically significant differences (p ≤ 0.05) between the groups. Right-handers predominantly exhibited left-to-right strokes (98%-100%), while left-handers showed greater variability. Although statistically significant for most letters analyzed, slope direction did not demonstrate consistent patterns. A logistic regression model was developed and validated on the same sample to classify handedness based on the averaged strokes of the letter "t." The model was further tested on samples (n = 252) from a publicly available handwriting database. If the model classified the sample as produced by left hand, it was correct in 100% of cases. In contrast, when the model classified writing as right-handed, it was correct in 73%-97% of cases, depending on the validation sample. The model classified writing as of left-handed origin if more than 36% of the letters "t" had a stroke from right to left, while otherwise, writing was classified as of right-handed origin. The developed method showed great potential for classifying the handedness of the author of disputed handwriting, thus eliminating individuals as text authors or narrowing down the pool of potential authors.

Handedness in Animals and Plants.

Structural and functional asymmetries are traceable in every form of life, and some lateralities are homologous. Functionally speaking, the division of labour between the two halves of the brain is a basic characteristic of the nervous system that arose even before the appearance of vertebrates. The most well-known expression of this specialisation in humans is hand dominance, also known as handedness. Even if hand/limb/paw dominance is far more commonly associated with the presence of a nervous system, it is also observed in its own form in aneural organisms, such as plants. To date, little is known regarding the possible functional significance of this dominance in plants, and many questions remain open (among them, whether it reflects a generalised behavioural asymmetry). Here, we propose a comparative approach to the study of handedness, including plants, by taking advantage of the experimental models and paradigms already used to study laterality in humans and various animal species. By taking this approach, we aim to enrich our knowledge of the concept of handedness across natural kingdoms.

Do sex and handedness influence general cognition and financial capacity in patients with aMCI and healthy older adults? Emphasis on women's performance.

Objectives: The effects of sex and handedness on financial capacity performance remain unexplored both in healthy older adults and in patients with amnestic mild cognitive impairment (aMCI). Methods: The aim of this study was to study the effect of the above factors (sex, handedness, and health condition), following a factorial experimental design; hence, eight groups (each with ten individuals) with similar demographic characteristics (age and education level) were formed consisting of right/left-handed, women/men and healthy/not healthy (with a diagnosis of aMCI) older adults. Mini-Mental State Examination (MMSE) was administered as a measure of general cognitive ability, and Legal Capacity for Property Law Transactions Assessment Scale (LCPLTAS) was used as an indicator of financial capacity; moreover, GDS-15 was used to assess depressive symptomatology. Self-reports of hand preference were also included. Results: Although as expected healthy men and women regardless of their handedness outperformed aMCI patients on MMSE and LCPLTAS, performance on cash transactions, bank statement management, bill payment, financial decision making, and knowledge of personal assets from LCPLTAS is significantly higher for right-handed aMCI women compared with left-handed aMCI women. Conclusions: Future research should further elucidate the reasons for this left-handed female patient with aMCI profile in larger groups of patients. This is an exploratory study, and the small sample size limits the strength of conclusions; further studies on this topic are needed.

Effect of Laterality in Microsurgery: Comparative Study of an Expert and a Novice.

Background: Hand laterality has an impact on surgical gestures. In this study, we sought to measure the multi-parameter variability of the microsurgical gesture depending on the hand used and the differences between expert microsurgeons and novices. Methods: Ten experienced microsurgeons and twenty medical students with no prior microsurgical experience performed arterial anastomosis on a chicken wing artery using dominant and non-dominant hands. We measured time and force using a homemade force-sensing microsurgical needle holder, heart rate variability with a Polar H10 chest strap, anxiety with the STAI-Y questionnaire and anastomosis quality using the MARS 10 scale. Results: In the microsurgeons' group, duration of anastomosis (p = 0.037), force applied to the needle holder (p = 0.047), anxiety (p = 0.05) and MARS10 (p = 0.291) were better with the dominant hand. For novices, there was no difference between the dominant and non-dominant hand pertaining to force, time and stress level. There were no differences between microsurgeons and novices pertaining to force and anxiety using the non-dominant hand. Conclusions: The study highlighted a marked laterality among microsurgical experts, a finding that may be explained by current learning methods. Surprisingly, no laterality is observed in students, suggesting that for a specific gesture completely different from everyday tasks, laterality is not predefined. Ambidexterity training in the residency curriculum seems relevant and may help microsurgeons improve performance and postoperative outcomes.