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Frontiers in Neuroscience 2023The aim of the present study is to evaluate the effect of vibrotactile stimulation prior to repeated complex motor imagery of finger movements using the non-dominant...
PURPOSE
The aim of the present study is to evaluate the effect of vibrotactile stimulation prior to repeated complex motor imagery of finger movements using the non-dominant hand on motor imagery (MI) performance.
METHODS
Ten healthy right-handed adults (4 females and 6 males) participated in the study. The subjects performed motor imagery tasks with and without a brief vibrotactile sensory stimulation prior to performing motor imagery using either their left-hand index, middle, or thumb digits. Mu- and beta-band event-related desynchronization (ERD) at the sensorimotor cortex and an artificial neural network-based digit classification was evaluated.
RESULTS
The ERD and digit discrimination results from our study showed that ERD was significantly different between the vibration conditions for the index, middle, and thumb. It was also found that digit classification accuracy with-vibration (mean ± SD = 66.31 ± 3.79%) was significantly higher than without-vibration (mean ± SD = 62.68 ± 6.58%).
CONCLUSION
The results showed that a brief vibration was more effective at improving MI-based brain-computer interface classification of digits within a single limb through increased ERD compared to performing MI without vibrotactile stimulation.
PubMed: 37360173
DOI: 10.3389/fnins.2023.1152563 -
Royal Society Open Science Jan 2018We revisit digit reduction in the horse and propose that all five digits are partially present in the modern adult forelimb. Osteological descriptions of selected...
We revisit digit reduction in the horse and propose that all five digits are partially present in the modern adult forelimb. Osteological descriptions of selected tetradactyl, tridactyl and monodactyl equids demonstrate the evolution of the forelimb. Histological, osteological and palaeontological evidence suggest that the distal forelimb is more complex than traditionally conceived. The current understanding is that the horse distal forelimb consists of one complete digit (III) and two reduced splint metacarpals (II and IV). Metacarpals II and IV each exhibit a ventral ridge, which we suggest represents the undifferentiated digits I and V. These ridges are present in the tridactyl , but are absent in the tetradactyl The carpal articulations of the five metacarpals match those of pentadactyl taxa. Distally, the frog, a V-shaped structure on the ventral hoof represents digits II and IV, and the wings and hoof cartilages of the distal phalanx are digits I and V. We relate this revised interpretation of the forelimb to Laetoli footprints, and suggest the side impressions are created from the hooves of I and V, rather than from II and IV. We show shades of pentadactyly within the manus.
PubMed: 29410871
DOI: 10.1098/rsos.171782 -
JPRAS Open Jun 2022Polydactyly is characterized by the manifestation of supernumerary digits in the hands and feet. It can be isolated or associated with a genetic syndrome. Based on the...
Polydactyly is characterized by the manifestation of supernumerary digits in the hands and feet. It can be isolated or associated with a genetic syndrome. Based on the location of duplication, it is categorized as preaxial, postaxial, or central. The latter is a rare abnormality, comprising approximately 6% of cases. There is a paucity in the literature regarding this congenital anomaly and its overall management. Nonoperative treatment is generally unsuccessful in managing symptoms such as excessive width, abnormal digit alignment, and growth. Though surgical management addresses the individual patient's needs, general goals include preservation of digits with the greatest axial alignment, resection of symptomatic digits, alignment correction of the remaining great toe, stabilization of the soft tissues, and adequate soft tissue coverage. This study aims to delineate effective operative techniques for central foot polydactyly. Two patient cases are discussed, providing a framework for pre and postoperative care, complications, and outcomes. The techniques detailed offer a straightforward, efficacious, and safe method to reconstruct central foot polydactyly, returning form and function to the patient.
PubMed: 35330745
DOI: 10.1016/j.jpra.2022.01.006 -
Annals of Plastic Surgery Jun 2024A common consideration for replantation success is the ischemia time following injury and the preservation temperature. A classic principle within the hand surgery... (Meta-Analysis)
Meta-Analysis
INTRODUCTION
A common consideration for replantation success is the ischemia time following injury and the preservation temperature. A classic principle within the hand surgery community describes 12 hours of warm ischemia and 24 hours of cold ischemia as the upper limits for digit replantation; however, these limits are largely anecdotal and based on older studies. We aimed to compare survival data from the large body of literature to aid surgeons and all those involved in the replantation process in hopes of optimizing success rates.
METHODS
The PubMed database was queried on April 4th, 2023, for articles that included data on digit replantation survival in terms of temperature of preservation and ischemia time. All primary outcomes were analyzed with the Mantel-Haenszel method within a random effects model. Secondary outcomes were pooled and analyzed using the chi-square statistic. Statistical analysis and forest plot generation were completed with RevMan 5.4 software with odds ratios calculated within a 95% confidence interval.
RESULTS
Our meta-analysis identified that digits preserved in cold ischemia for over 12 hours had significantly higher odds of replantation success than the amputated digits replanted with 0-12 hours of warm ischemia time ( P ≤ 0.05). The odds of survival in the early (0-6 hours) replantation group were around 40% greater than the later (6-12 hours) replantation group ( P ≤ 0.05). Secondary outcomes that were associated with higher survival rates included a clean-cut amputation, increased venous and arterial anastomosis, a repair that did not require a vein graft, and replants performed in nonsmokers ( P ≤ 0.05).
DISCUSSION
Overall, these findings suggest that when predicting digit replantation success, time is of the essence when the digit has yet to be preserved in a cold environment. This benefit, however, is almost completely diminished when the amputated digit is appropriately maintained in a cold environment soon after injury. In conclusion, our results suggest that there is potential for broadening the ischemia time limits for digit replant survival outlined in the literature, particularly for digits that have been stored correctly in cold ischemia.
Topics: Humans; Replantation; Amputation, Traumatic; Finger Injuries; Time Factors; Fingers; Warm Ischemia; Cold Ischemia; Ischemia; Temperature
PubMed: 38725110
DOI: 10.1097/SAP.0000000000003944 -
Developmental Dynamics : An Official... May 2015The regrowth of amputated appendage extremities and the distal tips of digits represent models of tissue regeneration in multiple vertebrate taxa. In humans, digit tip... (Review)
Review
BACKGROUND
The regrowth of amputated appendage extremities and the distal tips of digits represent models of tissue regeneration in multiple vertebrate taxa. In humans, digit tip injuries, including traumatic amputation and crush injuries, are among the most common type of injury to the human hand. Despite clinical reports demonstrating natural regeneration of appendages in lower vertebrates and human digits, current treatment options are suboptimal, and are complicated by the anatomical complexities and functions of the different tissues within the digits.
RESULTS
In light of these challenges, we focus on recent advancements in understanding appendage regeneration from model organisms. We pay special attention to the cellular programs underlying appendage regeneration, where cumulative data from salamanders, fish, frogs, and mice indicate that regeneration occurs by the actions of lineage-restricted precursors. We focus on pathologic states and the interdependency that exists, in both humans and animal models, between the nail organ and the peripheral nerves for successful regeneration.
CONCLUSIONS
The increased understanding of regeneration in animal models may open new opportunities for basic and translational research aimed at understanding the mechanisms that support limb regeneration, as well as amelioration of limb abnormalities and pathologies.
Topics: Amputation, Traumatic; Animals; Finger Injuries; Humans; Mice; Regeneration
PubMed: 25715837
DOI: 10.1002/dvdy.24265 -
Cognition & Emotion Mar 2021Previous research on the spatial-numerical association of response codes (SNARC) has demonstrated that SNARC-compatible digit arrangements are processed faster and more...
Previous research on the spatial-numerical association of response codes (SNARC) has demonstrated that SNARC-compatible digit arrangements are processed faster and more accurately than SNARC-incompatible arrangements. Concurrently, processing speed and accuracy have been conceptualised as indicating processing fluency - the ease of information processing - which has been shown to entail affective downstream consequences. Bridging these two research lines for the first time, we investigated whether digit arrangements that are compatible to this association are affectively preferred to association-incompatible digit arrangements. In a line of four experiments (total = 786), German participants were asked to indicate how much they like the overall appearance of two digits that appear at the right and at the left side of the screen. Results from three of the four experiments suggest that digit arrangements that are compatible with this spatial-numerical association indeed trigger positive feelings. These preference patterns were not moderated by the horizontal distance between the two digits, pointing towards a stable phenomenon that is insensitive to contextual spatial cues.
Topics: Cognition; Cues; Emotions; Humans; Reaction Time; Space Perception
PubMed: 33174803
DOI: 10.1080/02699931.2020.1846018 -
Journal of Experimental Psychology.... Mar 2022Little is known about the mental representation of large multidigit numbers that are usually beyond our personal experience. The present study explored the processing...
Little is known about the mental representation of large multidigit numbers that are usually beyond our personal experience. The present study explored the processing mechanisms of these numbers in a series of experiments, using the numerical comparison task. Experiment 1 included within and between-scale comparisons of multidigit numbers varying in their left digits (e.g., 8,000,000), with one group comparing small numbers (tens, hundreds, and thousands) and the other large ones (millions, billions, and trillions). In Experiment 2, comparisons of small (tens, hundreds) and large (millions, billions) multidigit numbers that varied in their left and right digits (e.g., 8,000,003) were presented in separate blocks. Experiment 3 presented small and large multidigit numbers (from tens to trillions) that varied in their left digits in the same block. We found novel compatibility effects between the left digit and scale components, as well as between the left digit, right digit, and scale components, and extended the previously reported unit-decade compatibility effect to larger scales. We also obtained global and scale distance effects for all scales in most conditions. Both compatibility and distance effects showed context dependency in large, but not small, multidigit numbers. Overall, these results demonstrate that small and large multidigit numbers are processed differently. We discuss these differences and propose a processing model that accounts for them. (PsycInfo Database Record (c) 2022 APA, all rights reserved).
PubMed: 35389727
DOI: 10.1037/xlm0001126 -
Journal of Plastic, Reconstructive &... Sep 2023The replantation of multiple amputated digits is a technically challenging procedure for reconstructive surgeons that requires more time than the replantation of a...
PURPOSE
The replantation of multiple amputated digits is a technically challenging procedure for reconstructive surgeons that requires more time than the replantation of a single digit. We evaluated the effect of multiple-digit replantation on the success of digital replantation.
METHODS
Patients who experienced digital amputation and underwent digital replantation from January 2018 to December 2021 were studied retrospectively. Patients who experienced successful and failed replantation were compared, as were digits that survived or became necrotic after replantation. A multivariate logistic regression (MLR) analysis was performed to evaluate the independent factors of replanted digit survival.
RESULTS
There were 378 patients with 497 amputated digits who underwent digital replantation. Of all 378 patients, 298 underwent single-digit replantation, and the other 80 patients underwent multiple-digit replantation. A total of 83.3% of the replanted digits survived (414 of 497). Compared with patients with surviving replanted digits, significantly more patients with necrotic replanted digits underwent multiple-digit replantation (37.7% vs. 17.5%, p < 0.001). On the other hand, a digit that developed necrosis after replantation was more likely to have been involved in the replantation of three or more digits (16% vs. 29%, p = 0.005). The subsequent MLR analysis revealed that the likelihood of necrosis was 2.355 (p = 0.003) times higher in the replantation of three or more digits than in the replantation of one or two digits.
CONCLUSION
Patients who underwent multiple-digit replantation exhibited a higher incidence of necrosis in the replanted digits. In cases involving patients with multiple-digit amputation, it is crucial to prioritize and perform selective replantation based on the amputated digits.
Topics: Humans; Amputation, Traumatic; Finger Injuries; Retrospective Studies; Replantation; Fingers; Amputation, Surgical; Necrosis
PubMed: 37467694
DOI: 10.1016/j.bjps.2023.06.026 -
Attention, Perception & Psychophysics Apr 2021There is a growing body of research on ensemble perception, or our ability to form ensemble representations based on perceptual features for stimuli of varying levels of...
There is a growing body of research on ensemble perception, or our ability to form ensemble representations based on perceptual features for stimuli of varying levels of complexity, and more recently, on ensemble cognition, which refers to our ability to perceive higher-level properties of stimuli such as facial attractiveness or gaze direction. Less is known about our ability to form ensemble representations based on more abstract properties such as the semantic meaning associated with items in a scene. Previous work examining whether the meaning associated with digits can be incorporated into summary statistical representations suggests that numerical information from digit ensembles can be extracted rapidly, and likely using a parallel processing mechanism. Here, we further investigate whether participants can accurately generate summary representations of numerical value from digit sets and explore the effect of set size on their ability to do so, by comparing psychometric functions based on a numerical averaging task in which set size varied. Steeper slopes for ten- and seven-item compared to five-item digit sets provide evidence that displays with more digits yield more reliable discrimination between larger and smaller numerical averages. Additionally, consistent with previous reports, we observed a response bias such that participants were more likely to report that the numerical average was "greater than 5" for larger compared to smaller sets. Overall, our results contribute to evidence that ensemble representations for semantic attributes may be carried out via similar mechanisms as those reported for perceptual features.
Topics: Cognition; Face; Humans; Perception; Psychometrics; Semantics; Size Perception
PubMed: 33389674
DOI: 10.3758/s13414-020-02196-8 -
Developmental Biology Feb 2021The development of joints in the mammalian skeleton depends on the precise regulation of multiple interacting signaling pathways including the bone morphogenetic protein...
The development of joints in the mammalian skeleton depends on the precise regulation of multiple interacting signaling pathways including the bone morphogenetic protein (BMP) pathway, a key regulator of joint development, digit patterning, skeletal growth, and chondrogenesis. Mutations in the BMP receptor ACVR1 cause the rare genetic disease fibrodysplasia ossificans progressiva (FOP) in which extensive and progressive extra-skeletal bone forms in soft connective tissues after birth. These mutations, which enhance BMP-pSmad1/5 pathway activity to induce ectopic bone, also affect skeletal development. FOP can be diagnosed at birth by symmetric, characteristic malformations of the great toes (first digits) that are associated with decreased joint mobility, shortened digit length, and absent, fused, and/or malformed phalanges. To elucidate the role of ACVR1-mediated BMP signaling in digit skeletal development, we used an Acvr1;Prrx1-Cre knock-in mouse model that mimics the first digit phenotype of human FOP. We have determined that the effects of increased Acvr1-mediated signaling by the Acvr1 mutation are not limited to the first digit but alter BMP signaling, Gdf5+ joint progenitor cell localization, and joint development in a manner that differently affects individual digits during embryogenesis. The Acvr1 mutation leads to delayed and disrupted joint specification and cleavage in the digits and alters the development of cartilage and endochondral ossification at sites of joint morphogenesis. These findings demonstrate an important role for ACVR1-mediated BMP signaling in the regulation of joint and skeletal formation, show a direct link between failure to restrict BMP signaling in the digit joint interzone and failure of joint cleavage at the presumptive interzone, and implicate impaired, digit-specific joint development as the proximal cause of digit malformation in FOP.
Topics: Activin Receptors, Type I; Animals; Body Patterning; Bone Morphogenetic Proteins; Chondrogenesis; Disease Models, Animal; Forelimb; Growth Differentiation Factor 5; Growth Plate; Hindlimb; Joints; Mice; Myositis Ossificans; Osteogenesis; Signal Transduction; Smad1 Protein; Smad5 Protein; Stem Cells; Toes
PubMed: 33217406
DOI: 10.1016/j.ydbio.2020.11.004