Individual Digits Research Articles

Video-based diagnosis support system for pianists with Musician's dystonia.

Musician's dystonia is a task-specific movement disorder that deteriorates fine motor control of skilled movements in musical performance. Although this disorder threatens professional careers, its diagnosis is challenging for clinicians who have no specialized knowledge of musical performance. To support diagnostic evaluation, the present study proposes a novel approach using a machine learning-based algorithm to identify the symptomatic movements of Musician's dystonia. We propose an algorithm that identifies the dystonic movements using the anomaly detection method with an autoencoder trained with the hand kinematics of healthy pianists. A unique feature of the algorithm is that it requires only the video image of the hand, which can be derived by a commercially available camera. We also measured the hand biomechanical functions to assess the contribution of peripheral factors and improve the identification of dystonic symptoms. The proposed algorithm successfully identified Musician's dystonia with an accuracy and specificity of 90% based only on video footages of the hands. In addition, we identified the degradation of biomechanical functions involved in controlling multiple fingers, which is not specific to musical performance. By contrast, there were no dystonia-specific malfunctions of hand biomechanics, including the strength and agility of individual digits. These findings demonstrate the effectiveness of the present technique in aiding in the accurate diagnosis of Musician's dystonia.

P176 Ixekizumab significantly improves nail disease and adjacent joint tenderness and swelling in psoriatic arthritis

Abstract Background/Aims Nail psoriasis (PsO) is a strong predictor for the development of psoriatic arthritis (PsA) and has been reported in 63-83% of patients with PsA. Psoriatic nails are linked to arthritis in the adjacent distal interphalangeal joint (DIP) of fingers or interphalangeal joint of thumbs, and both can lead to severe functional impairment. In the SPIRIT-H2H study of adults with PsA, 354 of 566 participants had nail PsO and adjacent joint disease in at least one digit at baseline. At the group level, SPIRIT-H2H patients treated with ixekizumab (IXE) achieved significantly greater improvements in nail PsO compared to those treated with adalimumab (ADA). This analysis aimed to assess the treatment effects of IXE and ADA at the individual digit level among patients with PsA, nail PsO, and adjacent joint disease. Methods This post hoc analysis included 354 patients from SPIRIT-H2H (NCT03151551) treated with either IXE (N = 186) or ADA (N = 168) who had nail PsO (Nail Psoriasis Severity Index (NAPSI) total score >0) and adjacent joint disease (tenderness and/or swelling) in at least one digit at baseline. Treatment effects were assessed for each individual finger unit displaying nail PsO and adjacent joint disease; here, finger unit defines the nail and adjacent joint of an individual digit; adjacent joint refers to the DIP of fingers or the interphalangeal joint of thumbs. Nail PsO was measured using NAPSI in the fingers only. Joint involvement was measured by tender/swollen joint count scores (TJC68/SJC66). Patients were evaluated for both nail and joint involvement at baseline and Weeks 12, 16, 24, 32, 40, and 52. Proportions of finger units with resolution of nail PsO, and proportions of finger units with resolution of adjacent joint disease were analyzed using Chi-square tests. Non-responder imputation was used to handle missing data. Results There were 1309 (IXE=639, ADA=670) finger units affected by nail and adjacent joint disease at baseline. Resolution of psoriatic nail disease and resolution of adjacent tenderness and/or swelling of the finger unit was significantly higher with IXE vs ADA at all post-baseline assessments over 52 weeks. Joint tenderness was resolved in a significantly larger proportion of IXE-treated finger units vs ADA at all post-baseline assessments over 52 weeks. Joint swelling was resolved in a larger proportion of IXE-treated finger units vs ADA, and these differences reached statistical significance at all visits except Week 16 and Week 40. The tenderness and/or swelling of the finger unit resolved more rapidly than the adjacent nail disease. Conclusion IXE treatment showed a significant advantage over ADA in resolving nail PsO, joint tenderness, and joint swelling among the finger units with nail and adjacent joint disease of patients with PsA. Disclosure D. McGonagle: Consultancies; D. McGonagle has received consulting fees and/or honoraria and/or research grants from: AbbVie and Eli Lilly and Company. A. Kavanaugh: Consultancies; A. Kavanaugh has received consulting fees and/or honoraria from: AbbVie, Eli Lilly and Company, Janssen, Novartis, Pfizer, UCB Pharma. I. McInnes: Corporate appointments; Vice Principle & Head of College for University of Glasgow, non-executive board member of NHS Greater Glasgow & Clyde, non-executive director of Evelo, and trustee of Versus Arthritis. Consultancies; AbbVie, Amgen, Bristol Myers Squibb, Cabaletta Bio, Causeway Therapeutics, Eli Lilly and Company, Gilead Sciences, Janssen, Novartis, Pfizer, Sanofi Regeneron, and UCB Pharma. L. Kristensen: Grants/research support; AbbVie, Amgen, Biogen, Bristol Myers Squibb, Eli Lilly and Company, Gilead Sciences, Janssen, Merck Sharpe & Dohme, Novartis, Pfizer, and UCB Pharma. J. Merola: Consultancies; AbbVie, Amgen, Biogen, Bristol Myers Squibb, Dermavant, Eli Lilly and Company, Janssen, LEO Pharma, Novartis, Pfizer, Sanofi Regeneron, Sun Pharma, and UCB Pharma. B. Strober: Corporate appointments; Editor-in-Chief for the Journal of Psoriasis and Psoriatic Arthritis and scientific co-director and investigator for CorEvitas Psoriasis Registry. Consultancies; AbbVie, Alamar Biosciences, Almirall, Alumis, Amgen, Arcutis, Arena Pharmaceuticals, Aristea Therapeutics, Asana Biosciences, Boehringer Ingelheim, Bristol Myers Squibb, Connect Biopharma, Dermavant. Shareholder/stock ownership; Connect Biopharma and Mindera. Honoraria; Eli Lilly and Company, Evelo Biosciences, Immunic Therapeutics, Incyte Corporation, Janssen, Kangpu Pharmaceuticals, LEO Pharma, Maruho, Meiji Seika Pharma, Mindera, Nimbus Therapeutics, Novartis. Grants/research support; Pfizer, Protagonist Therapeutics, Regeneron, Sanofi Genzyme, Sun Pharma, UCB Pharma, Union Therapeutics, Ventyx Biosciences, and vTv Therapeutics. R. Bolce: Shareholder/stock ownership; R. Bolce is an employee and shareholder of Eli Lilly and Company. J.R. Lisse: Shareholder/stock ownership; J. Lisse is an employee and shareholder of Eli Lilly and Company. J. Pustizzi: Shareholder/stock ownership; J. Pustizzi is an employee and shareholder of: Eli Lilly and Company. C. Sapin: Shareholder/stock ownership; C. Sapin is an employee and shareholder of: Eli Lilly and Company. C. Ritchlin: Honoraria; AbbVie, Bristol Myers Squibb, Eli Lilly and Company, Janssen, Novartis, Pfizer, and UCB Pharma.

Development and external validation of a prediction model for digit replantation failure after traumatic amputations based on a prospective multicenter cohort.

Failure of digit replantation after traumatic amputation is difficult to predict. The authors aimed to develop a prognostic model to better identify factors that better predict replantation failure following traumatic digit amputation. In this multicenter prospective cohort, the authors identified patients who had received digit replantation between 1 January 2015 and 1 January 2019. Univariable and multivariable analyses were performed successively to identify independently predictive factors for failure of replanted digit. To reduce overfitting, the Bayesian information criterion was used to reduce variables in the original model. Nomograms were created with the reduced model after model selection. This model was then internally validated with bootstrap resampling and further externally validated in validation cohort. Digit replantation was failed in 101 of 1062 (9.5%) digits and 146 of 1156 digits (12.6%) in the training and validation cohorts, respectively. The authors found that six independent prognostic variables were associated with digit replantation failure: age, mechanism of injury, ischemia duration, smoking status, amputation pattern (complete or incomplete), and surgeon's experience. The prediction model achieved good discrimination, with concordance indexes of 0.81 (95% CI: 0.76-0.85) and 0.70 (95% CI: 0.65-0.74) in predicting digit failure in the training and validation cohorts, respectively. Calibration curves were well-fitted for both training and validation cohorts. The proposed prediction model effectively predicted the failure rate of digit replantation for individual digits of all patients. It could assist in selecting the most suitable surgical plan for the patient.

Association of the clinical components in the distal interphalangeal joint synovio-entheseal complex and subsequent response to ixekizumab or adalimumab in psoriatic arthritis.

To assess the frequency of simultaneous distal interphalangeal (DIP) joint disease and adjacent nail psoriasis (finger unit) among patients with psoriatic arthritis (PsA) and compare the efficacy of the interleukin (IL)-17A antagonist ixekizumab (IXE) and the tumour necrosis factor (TNF)-α inhibitor adalimumab (ADA). This post hoc analysis evaluated the simultaneous occurrence of DIP joint involvement (tenderness and/or swelling) and adjacent nail psoriasis among patients with PsA from the SPIRIT-H2H (NCT03151551) trial comparing IXE to ADA. Among patients with simultaneous DIP joint involvement and adjacent nail psoriasis in ≥ 1 digit at baseline, treatment effects were assessed through week 52 for each affected finger unit; 'finger unit' defines the connected DIP joint and adjacent nail of an individual digit. A total of 354 patients had simultaneous DIP joint involvement and adjacent nail psoriasis in ≥ 1 finger unit at baseline. Among them, 1309 (IXE = 639, ADA = 670) finger units had baseline DIP joint tenderness and/or swelling and adjacent nail psoriasis. Proportions of affected finger units achieving complete resolution were significantly higher with IXE vs ADA as early as week 12 (38.8% vs 28.4%, p< 0.0001) and at all post-baseline assessments through week 52 (64.9% vs 57.5%, p= 0.0055). In this study cohort, patients with DIP joint involvement almost always had adjacent nail psoriasis. Greater resolution of DIP joint tenderness, swelling, and adjacent nail psoriasis was achieved at all timepoints over 52 weeks through targeting IL-17A with IXE than TNF-α with ADA, which is noteworthy given prior comparable musculoskeletal outcomes for both drug classes.

Estimating lung function from computed tomography at the patient and lobe level using machine learning.

Automated estimation of Pulmonary function test (PFT) results from Computed Tomography (CT) could advance the use of CT in screening, diagnosis, and staging of restrictive pulmonary diseases. Estimating lung function per lobe, which cannot be done with PFTs, would be helpful for risk assessment for pulmonary resection surgery and bronchoscopic lung volume reduction. To automatically estimate PFT results from CT and furthermore disentangle the individual contribution of pulmonary lobes to a patient's lung function. We propose I3Dr, a deep learning architecture for estimating global measures from an image that can also estimate the contributions of individual parts of the image to this global measure. We apply it to estimate the separate contributions of each pulmonary lobe to a patient's total lung function from CT, while requiring only CT scans and patient level lung function measurements for training. I3Dr consists of a lobe-level and a patient-level model. The lobe-level model extracts all anatomical pulmonary lobes from a CT scan and processes them in parallel to produce lobe level lung function estimates that sum up to a patient level estimate. The patient-level model directly estimates patient level lung function from a CT scan and is used to re-scale the output of the lobe-level model to increase performance. After demonstrating the viability of the proposed approach, the I3Dr model is trained and evaluated for PFT result estimation using a large data set of 8433 CT volumes for training, 1775 CT volumes for validation, and 1873 CT volumes fortesting. First, we demonstrate the viability of our approach by showing that a model trained with a collection of digit images to estimate their sum implicitly learns to assign correct values to individual digits. Next, we show that our models can estimate lobe-level quantities, such as COVID-19 severity scores, pulmonary volume (PV), and functional pulmonary volume (FPV) from CT while only provided with patient-level quantities during training. Lastly, we train and evaluate models for producing spirometry and diffusion capacity of carbon mono-oxide (DLCO) estimates at the patient and lobe level. For producing Forced Expiratory Volume in one second (FEV1), Forced Vital Capacity (FVC), and DLCO estimates, I3Dr obtains mean absolute errors (MAE) of 0.377L, 0.297L, and 2.800mL/min/mm Hg respectively. We release the resulting algorithms for lung function estimation to the research community at https://grand-challenge.org/algorithms/lobe-wise-lung-function-estimation/ CONCLUSIONS: I3Dr can estimate global measures from an image, as well as the contributions of individual parts of the image to this global measure. It offers a promising approach for estimating PFT results from CT scans and disentangling the individual contribution of pulmonary lobes to a patient's lung function. The findings presented in this work may advance the use of CT in screening, diagnosis, and staging of restrictive pulmonary diseases as well as in risk assessment for pulmonary resection surgery and bronchoscopic lung volumereduction.

Learning a Hand Model from Dynamic Movements Using High-Density EMG and Convolutional Neural Networks.

Surface electromyography (sEMG) can sense the motor commands transmitted to the muscles. This work presents a deep learning method that can decode the electrophysiological activity of the forearm muscles into the movements of the human hand. We have recorded the kinematics and kinetics of the hand during a wide range of grasps and individual digit movements that cover 22 degrees of freedom of the hand at slow (0.5 Hz) and comfortable (1.5 Hz) movement speeds in 13 healthy participants. The input of the model consists of 320 non-invasive EMG sensors placed on the extrinsic hand muscles. Our network achieves accurate continuous estimation of both kinematics and kinetics, surpassing the performance of comparable networks reported in the literature. By examining the latent space of the network, we find evidence that it mapped EMG activity into the anatomy of the hand at the individual digit level. In contrast to what is observed from the low-pass filtered EMG and linear decoding approaches, we found that the full-bandwidth EMG (monopolar unfiltered) signals during synergistic and individual digit movements contain distinct neural embeddings that encode each movement of the human hand. These manifolds consistently represent the anatomy of the hand and are generalized across participants. Moreover, we found a task-specific distribution of the embeddings without any presence of correlated activations during multi- and individual-digit tasks. The proposed method could advance the control of assistive hand devices by providing a robust and intuitive interface between muscle signals and hand movements.

TRANSFORMATION OF THE SUBJECTIVITY OF THE MODERN INDIVIDUAL IN THE CONTEXT OF THE DIGITALIZATION OF SOCIETY

The article examines the state of formation of subjectivity in a modern individual, in particular, his or her attitude to social freedom. It has been clarified how these attitudes to freedom differ significantly from established, traditional ideas about this most important factor in the formation of a person. It is traced how ideas about freedom are connected with three types of societies, according to the conceptualization of M. Foucault – the society of the sovereign, the disciplinary society, the society of control in its current digital version – as a society of surveillance capitalism. The history of the emergence of the concepts of biopower, biopolitics and biomass in M. Foucault is analyzed, starting with the study of disciplinary society. It was revealed that in order to ensure the management of the masses of people and the control over each individual, biopower embodied a mechanism even in the times of the disciplinary society, which has gained further development in the modern society of control. Its main content involves the transformation of an individual into a social subject while preserving the totalization of the population as biomass. It is shown that the formation of modern subjectivity is simultaneously undertaken by the state in the form of performing a totalizing and individualizing function, from which the individual tries to slip away with the help of his practices and techniques of freedom that guarantee subjectivation. It is considered how the latest digital technologies adapt the socio-philosophical doctrine of neo-behaviorism, which justifies the control and formation of an individual's behavior at all levels of his life, and how this ensures the manipulation of freedom in the broadest sense and puts the population on the verge of endless survival. It can be stated that the launched worldwide technologies for managing the behavior of individuals as biomass and the process of individual digitization significantly transform the subjectivity of modern individuals. As a result of this long-term process of modern biopolitics, there is a possibility that individuals will lose the significance of freedom and the role of democratic institutions in society will decrease, and neoliberalism can become a «nurture medium» for the formation of digital totalitarian regimes.

Online dynamical learning and sequence memory with neuromorphic nanowire networks

Nanowire Networks (NWNs) belong to an emerging class of neuromorphic systems that exploit the unique physical properties of nanostructured materials. In addition to their neural network-like physical structure, NWNs also exhibit resistive memory switching in response to electrical inputs due to synapse-like changes in conductance at nanowire-nanowire cross-point junctions. Previous studies have demonstrated how the neuromorphic dynamics generated by NWNs can be harnessed for temporal learning tasks. This study extends these findings further by demonstrating online learning from spatiotemporal dynamical features using image classification and sequence memory recall tasks implemented on an NWN device. Applied to the MNIST handwritten digit classification task, online dynamical learning with the NWN device achieves an overall accuracy of 93.4%. Additionally, we find a correlation between the classification accuracy of individual digit classes and mutual information. The sequence memory task reveals how memory patterns embedded in the dynamical features enable online learning and recall of a spatiotemporal sequence pattern. Overall, these results provide proof-of-concept of online learning from spatiotemporal dynamics using NWNs and further elucidate how memory can enhance learning.

Feasibility and usability of a virtual-reality-based sensorimotor activation apparatus for carpal tunnel syndrome patients.

This study aimed to assess the usability of a virtual reality-assisted sensorimotor activation (VRSMA) apparatus for individual digit rehabilitation. The study had two main objectives: Firstly, to collect preliminary data on the expectations and preferences of patients with carpal tunnel syndrome (CTS) regarding virtual reality (VR) and an apparatus-assisted therapy for their affected digits. Secondly, to evaluate the usability of the VRSMA apparatus that was developed. The VRSMA system consists of an apparatus that provides sensory and motor stimulation via a vibratory motor and pressure sensor attached to a button, and a virtual reality-based visual cue provided by texts overlaid on top of a 3D model of a hand. The study involved 10 CTS patients who completed five blocks of VRSMA with their affected hand, with each block corresponding to the five digits. The patients were asked to complete a user expectations questionnaire before experiencing the VRSMA, and a user evaluation questionnaire after completing the VRSMA. Expectations for VRSMA were obtained from the questionnaire results using a House of Quality (HoQ) analysis. In the survey for expectations, participants rated certain attributes as important for a rehabilitation device for CTS, with mean ratings above 4 for attributes such as ease of use, ease of understanding, motivation, and improvement of hand function based on clinical evidence. The level of immersion and an interesting rehabilitation regime received lower ratings, with mean ratings above 3.5. The survey evaluating VRSMA showed that the current prototype was overall satisfactory with a mean rating of 3.9 out of 5. Based on the HoQ matrix, the highest priority for development of the VRSMA was to enhance device comfort and usage time. This was followed by the need to perform more clinical studies to provide evidence of the efficacy of the VRSMA. Other technical characteristics, such as VRSMA content and device reliability, had lower priority scores. The current study presents a potential for an individual digit sensorimotor rehabilitation device that is well-liked by CTS patients.

Outcomes following replantation surgery.

The ability to perform surgical replantation of individual digits and limbs can provide substantial functional improvement for patients who sustain devastating upper extremity injuries. Defining success in replantation surgery extends beyond the acute period and the binary metrics of survival or loss of the replanted part to include the long-term overall functional outcomes. Functional outcomes include both objective clinical evaluation and patient-reported outcomes. There has been significant variation in the way outcomes following replantation are measured, which inherently leads to heterogeneity in the reported outcome data. Given the variability among outcome measures, we aim to explore the outcomes of replantation surgery, particularly clinical evaluation and patient-reported functional outcomes following replantation.

P169 Treatment effects of ixekizumab and adalimumab at the individual digit level with nail and distal interphalangeal joint involvement in patients with psoriatic arthritis

Abstract Background/Aims Psoriatic nail disease is intimately linked to adjacent distal interphalangeal joint (DIP) disease, and it is important to ascertain whether DIP-nail complex behaves differently under different biological therapies. The aim of this analysis is to assess the effect of ixekizumab (IXE) and adalimumab (ADA) at the individual digit level using the Nail Psoriasis Severity Index (NAPSI) and NAPSI resolution in patients with psoriatic arthritis (PsA) with concomitant nail involvement. Methods This post hoc analysis included patients from SPIRIT-H2H (NCT03151551) treated with either IXE or ADA who had baseline nail disease (NAPSI total score &amp;gt;0) and DIP involvement, with either tenderness or swelling, at the individual digit level for each hand. Nail disease was assessed using the NAPSI scoring system, a measure of nail bed and nail matrix involvement combined for a total maximum score of 80. Proportions of patients having a NAPSI total score &amp;gt;0 were evaluated at baseline, week 24 and week 52; post-baseline assessments were compared between treatment using Fisher’s exact test. Results Of 566 patients in the intent-to-treat SPIRIT-H2H population of, 354 patients (IXE, N = 186; ADA, N = 168) had NAPSI total score &amp;gt;0 and DIP involvement in at least 1 of 10 digits simultaneously at baseline. At week 24, the proportion of patients with nail disease (NAPSI &amp;gt;0) was lower among patients who received IXE versus ADA across all 10 digits and was significantly lower versus ADA for 9 out of the 10 individual digits (p &amp;lt; 0.05; Table) with additional improvements out to week 52. On average, a 10% difference in the proportion of patients with NAPSI &amp;gt;0 at week 24 between IXE and ADA at the individual digit level was observed, favouring IXE. Similarly, numerically greater improvements were observed with IXE compared to ADA regardless of whether nail bed, nail matrix, or NAPSI total score was assessed. Conclusion These data demonstrate that in patients with PsA with nail involvement, there was a significant advantage of IXE over ADA in resolving nail involvement at the individual digit level as measured by NAPSI. Disclosure D. McGonagle: Consultancies; Eli Lilly and Company, AbbVie. Member of speakers’ bureau; Eli Lilly and Company. Grants/research support; Eli Lilly and Company. Other; BSR attendance support from Eli Lilly and Company. A. Kavanaugh: Consultancies; AbbVie, UCB, Janssen, Novartis, Pfizer. I. McInnes: Consultancies; AbbVie, Amgen, BMS, Causeway Therapeutics, Cabaletta, Eli Lilly and Company, Gilead, Janssen, Novartis, Pfizer, Sanofi Regeneron, UCB. Grants/research support; AbbVie, Amgen, BMS, Causeway Therapeutics, Cabaletta, Eli Lilly and Company, Gilead, Janssen, Novartis, Pfizer, Sanofi Regeneron, UCB Pharma. Other; University of Glasgow, Vice Principal &amp; Head of College, NHS Greater Glasgow &amp; Clyde, Non exec board member, Evelo, Board of Directors, Non Exec director, Versus arthritis, Trustee. L. Kristensen: Consultancies; Pfizer, AbbVie, Amgen, UCB, Gilead, Biogen, BMS, MSD, Novartis, Eli Lilly and Company, Janssen. Member of speakers’ bureau; Pfizer, AbbVie, Amgen, UCB, Gilead, Biogen, BMS, MSD, Novartis, Eli Lilly and Company, Janssen. Grants/research support; Pfizer, AbbVie, UCB, Gilead, Biogen, Novartis, Eli Lilly and Company, Janssen. Other; study grant from Novo Nordisk A/S, institutional grant from The Oak Foundation, Cambridge Weight Plan, delivery of dietary supplements. J.F. Merola: Consultancies; Amgen, Bristol-Myers Squibb, AbbVie, Dermavant, Eli Lilly and Company, Novartis, Janssen, UCB, Sanofi, Regeneron, Sun Pharma, Biogen, Pfizer, Leo Pharma. B.E. Strober: Consultancies; AbbVie, Alumis, Almirall, Amgen, Arcutis, Arena, Aristea, Asana, Boehringer Ingelheim, Immunic Therapeutics, Bristol-Myers-Squibb, Connect Biopharma, Dermavant, EPI Health, Evelo Biosciences, Janssen, Leo, Eli Lilly and Company, Maruho, Meiji Seika Pharma, Mindera Health, Novartis, Pfizer, UCB Pharma, Sun Pharma, Regeneron, Sanofi-Genzyme, Union Therapeutics, Ventyxbio, vTv Therapeutics. Shareholder/stock ownership; Connect Biopharma, Mindera Health. Honoraria; Editor-in-Chief (honorarium): Journal of Psoriasis and Psoriatic Arthritis. Member of speakers’ bureau; AbbVie, Eli Lilly and Company, Incyte, Janssen, Regeneron, Sanofi-Genzyme. Other; Investigator: Dermavant, Investigator: AbbVie, Investigator: CorEvitas Psoriasis Registry, Investigator: Dermira, Investigator: Cara, Investigator: Novertis. J.R. Lisse: Corporate appointments; Eli Lilly and Company. Shareholder/stock ownership; Eli Lilly and Company. J. Pustizzi: Corporate appointments; Eli Lilly and Company. Shareholder/stock ownership; Eli Lilly and Company. C. Sapin: Corporate appointments; Eli Lilly and Company. Shareholder/stock ownership; Eli Lilly and Company. R. Bolce: Corporate appointments; Eli Lilly and Company. Shareholder/stock ownership; Eli Lilly and Company. C. Ritchlin: Consultancies; AbbVie, Janssen, Novartis, BMS, UCB. Member of speakers’ bureau; Pfizer, UCB, AbbVie. Grants/research support; Pfizer, AbbVie.

Fingerprint patterns in neuropsychological disorder depression among south Indian population.

Depression is a pervasive mental health disorder characterized by persistent sadness and an inability to enjoy activities that were once enjoyable. This study compares the dermatoglyphic patterns of depressed patients with those of healthy, normal individuals in order to determine if dermatoglyphic patterns can be used as biomarkers for early diagnosis and prompt intervention of depression. A total of 100 depressive disorder patients of both sexes between the ages of 18 and 60 were selected for the study. Dermatoglyphic patterns of individual digits were analyzed using the "Ink and Paper" technique. The Whorl, Loop, and Arch patterns, as well as the AFRC, TFRC, and a-b ridge count, were examined using One-Way ANOVA significance and a Chi-Square test using SPSS 20.0. The results showed that the right hand in the depressive diseased group had decreased numbers of Whorls in the 2nd and 5th digits, and decreased numbers of Loops in all five digits. Similarly, decreased numbers of Whorls were found in the 1st, 2nd, 4th, and 5th digits of the left hand, as well as decreased Loops in the 4th digit. However, there were no changes in the Arches of either hand when compared to the control group. The AFRC and TFRC were significantly decreased (p<0.0001), but there was no significant decrease in the a-b ridge count in the depressive diseased group when compared to the control group. Dermatoglyphics, a noninvasive method, can serve as a screening indicator for depressive individuals, the appearance of the decreased count of whorls and loops parameters might be used as an exploratory sign.

Digits in a dish: An in vitro system to assess the molecular genetics of hand/foot development at single-cell resolution.

In vitro models allow for the study of developmental processes outside of the embryo. To gain access to the cells mediating digit and joint development, we identified a unique property of undifferentiated mesenchyme isolated from the distal early autopod to autonomously re-assemble forming multiple autopod structures including: digits, interdigital tissues, joints, muscles and tendons. Single-cell transcriptomic analysis of these developing structures revealed distinct cell clusters that express canonical markers of distal limb development including: Col2a1, Col10a1, and Sp7 (phalanx formation), Thbs2 and Col1a1 (perichondrium), Gdf5, Wnt5a, and Jun (joint interzone), Aldh1a2 and Msx1 (interdigital tissues), Myod1 (muscle progenitors), Prg4 (articular perichondrium/articular cartilage), and Scx and Tnmd (tenocytes/tendons). Analysis of the gene expression patterns for these signature genes indicates that developmental timing and tissue-specific localization were also recapitulated in a manner similar to the initiation and maturation of the developing murine autopod. Finally, the in vitro digit system also recapitulates congenital malformations associated with genetic mutations as in vitro cultures of Hoxa13 mutant mesenchyme produced defects present in Hoxa13 mutant autopods including digit fusions, reduced phalangeal segment numbers, and poor mesenchymal condensation. These findings demonstrate the robustness of the in vitro digit system to recapitulate digit and joint development. As an in vitro model of murine digit and joint development, this innovative system will provide access to the developing limb tissues facilitating studies to discern how digit and articular joint formation is initiated and how undifferentiated mesenchyme is patterned to establish individual digit morphologies. The in vitro digit system also provides a platform to rapidly evaluate treatments aimed at stimulating the repair or regeneration of mammalian digits impacted by congenital malformation, injury, or disease.

Multi-finger receptive field properties in primary somatosensory cortex: A revised account of the spatiotemporal integration functions of area 3b

The leading view in the somatosensory system indicates that area 3b serves as a cortical relay site that primarily encodes (cutaneous) tactile features limited to individual digits. Our recent work argues against this model by showing that area 3b cells can integrate both cutaneous and proprioceptive information from the hand. Here, we further test the validity of this model by studying multi-digit (MD) integration properties in area 3b. In contrast to the prevailing view, we show that most cells in area 3b have a receptive field (RF) that extends to multiple digits, with the size of the RF (i.e., the number of responsive digits) increasing across time. Further, we show that MD cells' orientation angle preference is highly correlated across digits. Taken together, these data show that area 3b plays a larger role in generating neural representations of tactile objects, as opposed to just being a "feature detector" relay site.

Hierarchical and synergistic organization of control variables during the multi-digit grasp of a free and an externally fixed object.

In the referent control theory, grip force emerges by designating the referent aperture (Ra) as a threshold position inside the object. This study quantified Ra and investigated whether the synergistic control of digit referent coordinate (RC) and apparent stiffness (k) depend on the external mechanical constraints on the hand-held object. Subjects held a motorized handle capable of adjusting the grip width and performed static multi-digit prehension tasks in which the handle was free and externally fixed in different conditions. The RC and k of individual digits were reconstructed from the changes in digit normal forces and the positions as the grip width was modulated. RCs of the thumb and virtual finger were used to calculate the width and midpoint of Ra, and synergy indices quantifying the task-specific covariation in the space of the digit normal forces and {RC, k} variables were computed. We found that the k and width of the Ra were larger when holding a free handle than the fixed handle. The higher stiffness in the free condition could be a strategy to ensure grip stability. The midpoint of Ra was skewed toward the virtual finger, reflecting different magnitudes of k for the two digits. Further, the normal forces and control variables {RC, k} displayed synergistic covariation for stabilization of the total grasping force. Finally, the synergies were weaker when the handle was externally fixed, demonstrating the dependence of synergies on external constraints. These results add to the current literature by demonstrating that grasp control involves modulation of digit apparent stiffness in addition to the referent coordinate and by identifying the synergistic organization of the control variables during static grasp.

A Generalized Framework for the Study of Spinal Motor Neurons Controlling the Human Hand During Dynamic Movements.

The human hand possesses a large number of degrees of freedom. Hand dexterity is encoded by the discharge times of spinal motor units (MUs). Most of our knowledge on the neural control of movement is based on the discharge times of MUs during isometric contractions. Here we designed a noninvasive framework to study spinal motor neurons during dynamic hand movements with the aim to understand the neural control of MUs during sinusoidal hand digit flexion and extension at different rates of force development. The framework included 320 high-density surface EMG electrodes placed on the forearm muscles, with markerless 3D hand kinematics extracted with deep learning, and a realistic virtual hand that displayed the motor tasks. The movements included flexion and extension of individual hand digits at two different speeds (0.5 Hz and 1.5 Hz) for 40 seconds. We found on average 4.7±1.7 MUs across participants and tasks. Most MUs showed a biphasic pattern closely mirroring the flexion and extension kinematics. Indeed, a factor analysis method (non-negative matrix factorization) was able to learn the two components (flexion/extension) with high accuracy at the individual MU level ( R=0.87±0.12). Although most MUs were highly correlated with either flexion or extension movements, there was a smaller proportion of MUs that was not task-modulated and controlled by a different neural module (7.1% of all MUs with ). This work shows a noninvasive visually guided framework to study motor neurons controlling the movement of the hand in human participants during dynamic hand digit movements.

Dual chirped microcomb based parallel ranging at megapixel-line rates

Laser-based ranging (LiDAR) - already ubiquitously used in industrial monitoring, atmospheric dynamics, or geodesy - is a key sensor technology. Coherent laser ranging, in contrast to time-of-flight approaches, is immune to ambient light, operates continuous-wave allowing higher average powers, and yields simultaneous velocity and distance information. State-of-the-art coherent single laser-detector architectures reach hundreds of kilopixel per second sampling rates, while emerging applications - autonomous driving, robotics, and augmented reality - mandate megapixel per second point sampling to support real-time video-rate imaging. Yet, such rates of coherent LiDAR have not been demonstrated. Recent advances in photonic chip-based microcombs provide a route to higher acquisition speeds via parallelization but require separation of individual channels at the detector side, increasing photonic integration complexity. Here we overcome the challenge and report a hardware-efficient swept dual-soliton microcomb technique that achieves coherent ranging and velocimetry at megapixel per second line scan measurement rates with up to 64 optical channels. Multiheterodyning two synchronously frequency-modulated microcombs yields distance and velocity information of all individual ranging channels on a single receiver alleviating the need for individual separation, detection, and digitization. The reported LiDAR implementation is compatible with photonic integration and demonstrates the significant advantages of acquisition speed afforded by the convergence of optical telecommunication and metrology technologies.

3. MOTOR CONTROL OF INDIVIDUAL DIGITS OF A ROBOTIC HAND USING ONLY SIGNALS RECORDED FROM THE PERIPHERAL NERVES

PURPOSE: Despite advances in artificial sensory feedback and EMG-based motor control, robotic hand “dexterity” remains elusive due to the inability to provide reliable individual digit motor control. We previously demonstrated functionally-relevant tactile and proprioceptive sensory feedback using fascicle-specific targeting of longitudinal intrafascicular electrodes (FAST-LIFE interfaces) implanted in the residual nerves of the amputated upper limb. Here we describe advances in motor control obtained by combining FAST-LIFE interfacing with peripheral nerve-specific motor control technology developed by our group. METHODS: Oversight by the UTSW IRB. 6 patient trials were performed, duration 3 - 15 months. Amputation level: 3 partial hand (FAST-LIFE interfaces in motor/sensory fascicles of ulnar nerve); 3 transradial (FAST-LIFE interfaces in motor/sensory fascicles of median + ulnar nerves). RESULTS: We demonstrated individual digit control of a robotic hand prosthesis using: 1) FAST-LIFE interfacing, 2) hardware for recording peripheral nerve signals, 3) machine learning decoding of motor intent, and 4) portable controllers for individual digit actuation. Details of decoding accuracy, task matching trials, and individual digit control will be discussed. The study culminated in a “take-home” trial. CONCLUSION: Individual digit control of a robotic hand prosthesis can be accomplished using only signals derived from FAST-LIFE implants placed in the residual nerves of the amputated upper limb. Our novel motor control strategy holds promise for robotic hand control in higher level amputations, where conventional EMG sensors are ineffective due to total absence of the forearm muscles.

Children’s mixed-rounding strategy use in computational estimation

Being able to perform computational estimations efficiently is an important skill. Furthermore, computational estimation experiments are used to study general principles in strategy development. Rounding strategies are common in computational estimation. However, little is known about whether and when children use a mixed-rounding strategy (i.e., both rounding up and down in one estimation) and how demanding this is in comparison to only rounding-down or only rounding-up. Therefore, we systematically varied the size of unit digits (i.e., the rightmost digit in a whole number) in 72 addition problems. These estimation problems were presented to fourth graders. Most children preferred to use mixed-rounding on mixed-unit problems and therefore adjusted their strategy choice to the individual unit digits in a calculation. Additionally, the sum of units barely influenced children’s strategy choice. On mixed-rounding calculations, the proportion of best strategy use was comparable to that of rounding-up and the latencies to produce an estimate with mixed-rounding were between those for rounding-down and rounding-up. Therefore, the mixed-rounding strategy was in the difficulty range of the two more frequently studied rounding strategies; it was also the preferred strategy for mixed-unit problems by children who adapted their estimation strategies. Based on these findings we argue that research into strategy development with estimation tasks should also include mixed-rounding to improve ecological validity.

Digit specific denervation does not inhibit mouse digit tip regeneration

It is long-established that innervation-dependent production of neurotrophic factors is required for blastema formation and epimorphic regeneration of appendages in fish and amphibians. The regenerating mouse digit tip and the human fingertip are mammalian models for epimorphic regeneration, and limb denervation in mice inhibits this response. A complicating issue of limb denervation studies in terrestrial vertebrates is that the experimental models also cause severe paralysis therefore impairing appendage use and diminishing mechanical loading of the denervated tissues. Thus, it is unclear whether the limb denervation impairs regeneration via loss of neurotrophic signaling or loss of mechanical load, or both. Herein, we developed a novel surgical procedure in which individual digits were specifically denervated without impairing ambulation and mechanical loading. We demonstrate that digit specific denervation does not inhibit but attenuates digit tip regeneration, in part due to a delay in wound healing. However, treating denervated digits with a wound dressing that enhances closure results in a partial rescue of the regeneration response. Contrary to the current understanding of mammalian epimorphic regeneration, these studies demonstrate that mouse digit tip regeneration is not peripheral nerve dependent, an observation that should inform continued mammalian regenerative medicine approaches.