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Computational neural network provides naturalistic solution for recovery of finger dexterity after stroke [article]

Ashraf Kadry, Sumner Norman, Jing Xu, Deborah Solomonow-Avnon, Firas Mawase
2021 biorxiv/medrxiv   pre-print
Finger dexterity is a fundamental movement skill of humans and the ability to individuate fingers imparts high motor flexibility.  ...  We explored the hypothesis that interactive connections between cortical and subcortical neurons reflect dynamics appropriate for generating outgoing commands for finger movement.  ...  The input layer represents the commands for finger movements 133 generated by motor cortical areas and is used to feed the NN.  ... 
doi:10.1101/2021.06.22.449412 fatcat:iq5pzxaxgfd75aprq7mfc6mtue

The cortical dynamics orchestrating skilled prehension [article]

Britton Sauerbrei, Jian-Zhong Guo, Jihong Zheng, Wendy Guo, Mayank Kabra, Nakul Verma, Kristin Branson, Adam Hantman
2018 bioRxiv   pre-print
Skillful control of movement is central to our ability to sense and manipulate the world. Dexterous acts depend on cerebral cortex, and the activity of cortical neurons is correlated with movement.  ...  By combining electrophysiology and optogenetic perturbations, we have identified and characterized the cortical motor program driving a learned, dexterous movement sequence.  ...  that the motor cortex is not autonomous during movement execution, but must be driven by strong external input.  ... 
doi:10.1101/266320 fatcat:hbcrcydfjvg5hdewtgvafmzola

The Pontine Nuclei are an Integrative Cortico-Cerebellar Link Critical for Dexterity [article]

Jian-Zhong Guo, Britton Sauerbrei, Jeremy Cohen, Matteo Mischiati, Austin Graves, Ferruccio Pisanello, Kristin Branson, Adam Hantman
2019 bioRxiv   pre-print
Although PN neurons occupy an important anatomical position, little is known about their firing properties during natural movement, feedback effects on cortical activity, or functional role in behavior  ...  Third, perturbations of PN function impair performance of reaching, disrupt limb kinematics, and alter the functional responses of motor cortical neurons during movement.  ...  Results Firing properties of PN neurons during a dexterous, cortically-dependent behavior.  ... 
doi:10.1101/637447 fatcat:3q65pyntpbd7rjdhlbyeys4duq

Recent advances in our understanding of the primate corticospinal system

Roger Lemon
2019 F1000Research  
This system, which is unique to dexterous primates, is probably at its most advanced level in humans.  ...  We now know much more about the origin of the CM system within the cortical motor network, and its connectivity within the spinal cord has been quantified.  ...  and pattern of muscle activity) from that which is 'extrinsic-like' (that is, resembles the direction of movement produced, independent of arm posture).  ... 
doi:10.12688/f1000research.17445.1 pmid:30906528 pmcid:PMC6415323 fatcat:2bi4yatjvvazdiow32rv4a6dim

Learning in the Rodent Motor Cortex

Andrew J. Peters, Haixin Liu, Takaki Komiyama
2017 Annual Review of Neuroscience  
The motor cortex is far from a stable conduit for motor commands and instead undergoes significant changes during learning.  ...  This synaptic reorganization translates into changes in spiking activity, which appear to result in a modification and refinement of the relationship between motor cortical activity and movement.  ...  Corticospinal cells may be the ultimate drivers of cortex-driven movement, but they can be accessed either directly by frontal cortical areas for general dexterous movements or indirectly by first going  ... 
doi:10.1146/annurev-neuro-072116-031407 pmid:28375768 pmcid:PMC5714655 fatcat:thhdrai3ezag3jzttokunf2mom

Cortical Reorganization of Sensorimotor Systems and the Role of Intracortical Circuits After Spinal Cord Injury

Hisham Mohammed, Edmund R. Hollis
2018 Neurotherapeutics  
Spinal cord injury, which both deprives afferent input and interrupts efferent output, results in a disruption of cortical somatotopy.  ...  This review focuses on the reorganization of cortical networks observed after injury and posits a role of intracortical circuits in recovery.  ...  Similarly, rodents exhibit cortical reorganization during dexterous motor learning.  ... 
doi:10.1007/s13311-018-0638-z pmid:29882081 fatcat:aqkwspcqffaoziqkoq5dkzsrzm

Motor cortical dynamics are shaped by multiple distinct subspaces during naturalistic behavior [article]

Matthew G Perich, Sara Conti, Marion Badi, Andrew Bogaard, Beatrice Barra, Sophie Wurth, Jocelyne Bloch, Gregoire Courtine, Silvestro Micera, Marco Capogrosso, Tomislav Milekovic
2020 bioRxiv   pre-print
We therefore demonstrate that cortical activity is compartmentalized within distinct subspaces that shape the population dynamics, enabling flexible integration of salient inputs with ongoing activity  ...  During error correction, the communication subspace became feedback-driven, while the behavioral subspace maintained feedforward dynamics.  ...  Motor cortical population activity is driven by unexpected inputs on error trials.  ... 
doi:10.1101/2020.07.30.228767 fatcat:p4oikbden5dsteyioo5q54ow74

Ipsilateral finger representations are engaged in active movement, but not sensory processing [article]

Eva Berlot, George Prichard, Jill O'Reilly, Naveed Ejaz, Joern Diedrichsen
2018 bioRxiv   pre-print
Here, we asked whether human ipsilateral representations are caused by active movement, or whether they are driven by sensory input.  ...  During unimanual movements, activity in the contralateral hemisphere is increased while the ipsilateral hemisphere is suppressed below resting baseline.  ...  These findings suggest that ipsilateral representations in these 436 areas are driven by processes involved in the active generation of movement, but not by the 437 sensory input arising from passive movement  ... 
doi:10.1101/285809 fatcat:nlaf72qz4bgbfoe5xvkggc4ase

Electrocorticographic amplitude predicts finger positions during slow grasping motions of the hand

Soumyadipta Acharya, Matthew S Fifer, Heather L Benz, Nathan E Crone, Nitish V Thakor
2010 Journal of Neural Engineering  
coefficient, r; median = 0.51, maximum = 0.91), during displacements of up to 10 cm at the fingertips.  ...  Four human subjects undergoing subdural electrocorticography for epilepsy surgery engaged in a range of finger and hand movements.  ...  This could lead to marked nonstationarity in the pattern and rhythm of hand movements performed during the motor tasks.  ... 
doi:10.1088/1741-2560/7/4/046002 pmid:20489239 pmcid:PMC4021582 fatcat:dwokipgoqvdhvh2vvkugxhjv4i

Sparse Eigenmotions derived from daily life kinematics implemented on a dextrous robotic hand

Charalambos Konnaris, Andreas A. C. Thomik, A. Aldo Faisal
2016 2016 6th IEEE International Conference on Biomedical Robotics and Biomechatronics (BioRob)  
We take an approach grounded in data-driven extraction of control primitives from natural human behaviour to develop novel ways to understand the dexterity of hands.  ...  We report that without processing any feedback during grasp control, several of the SEMs resulted in stable grasps of different daily life objects.  ...  While it is unclear what criteria of optimality the brain uses, it has been suggested that due to the significantly larger number of cortical neurons being driven by a comparatively smaller number of sensory  ... 
doi:10.1109/biorob.2016.7523821 dblp:conf/biorob/KonnarisTF16 fatcat:jdcthqfosneibmhkyd5awjsy24

How Much Evidence do we have on the Central Effects of Botulinum Toxin in Spasticity and Dystonia? [chapter]

Tomáš Veverka, Martin Nevrly, Pavel Otruba, Petr Hluštík, Petr Kanovsky
2016 Botulinum Toxin Therapy Manual for Dystonia and Spasticity  
The brain is continually reorganizing (plasticity). Plastic changes within the sensorimotor system are not only beneficial (adaptive plasticity) but may even worsen function (maladaptive plasticity).  ...  Beside the well-known neuromuscular junction site of action, BoNT also exerts effects through supraspinal mechanisms and can even affect cortical reorganization.  ...  It is generally recognized that PSS may interfere with voluntary movement [14] .  ... 
doi:10.5772/64763 fatcat:6utsxdmlc5ao3asrwgx65hlxq4

Ipsilateral finger representations in the sensorimotor cortex are driven by active movement processes, not passive sensory input

Eva Berlot, George Prichard, Jill O'Reilly, Ejaz Naveed, Jorn Diedrichsen
2018 Journal of Neurophysiology  
Here, we asked whether ipsilateral representations are caused by active movement, or whether they are driven by sensory input.  ...  During unimanual movements, activity in the contralateral hemisphere is increased while the ipsilateral hemisphere is suppressed below resting baseline.  ...  These findings suggest that ipsilateral representations in these areas are driven by processes involved in the active generation of movement, but not by the sensory input arising from passive stimulation  ... 
doi:10.1152/jn.00439.2018 pmid:30517048 pmcid:PMC6397402 fatcat:f3v3u6ncdfguvjio7cctilnkuy

Circadian Biology: Rhythms Leave Their Imprint

David W. Ray
2015 Current Biology  
When motor cortex is lesioned in primates (including humans), a long-lasting deficit in dexterous movement results [10,11].  ...  Motor cortex targets many other brain regions that can themselves generate movement.  ... 
doi:10.1016/j.cub.2014.12.045 pmid:25734270 fatcat:acnbnibuqnbbjmzpx3hrdwtvga

Recovery after brain injury: mechanisms and principles

Randolph J. Nudo
2013 Frontiers in Human Neuroscience  
It is now generally accepted that acquired brain injuries, such as occur in stroke or trauma, initiate a cascade of regenerative events that last for at least several weeks, if not months.  ...  While there is substantial evidence for this principle in normal, healthy brains, the injured brain is particularly malleable.  ...  Perhaps, the novel connection between PMv and S1 is an attempt by the cortical motor systems to reconnect with somatosensory input.  ... 
doi:10.3389/fnhum.2013.00887 pmid:24399951 pmcid:PMC3870954 fatcat:gin26wv2ivevnl2rtsopqsvosy

Organized Toe Maps in Extreme Foot Users

Harriet Dempsey-Jones, Daan B. Wesselink, Jason Friedman, Tamar R. Makin
2019 Cell Reports  
We further reveal "hand-like" features of activity patterns, not only in the foot area but also similarly in the missing hand area.  ...  Although the fine-grained features of topographic maps in the somatosensory cortex can be shaped by everyday experience, it is unknown whether behavior can support the expression of somatotopic maps where  ...  DATA AND CODE AVAILABILITY Datasets generated during this study are available at Open Science Framework (https://osf.io/4q8cs/).  ... 
doi:10.1016/j.celrep.2019.08.027 pmid:31509738 pmcid:PMC6899508 fatcat:oykkdvlzljfrzcvfqzrc47gfwm
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