SCF ENCYCLOPEDIA ENTRY
SPINOCEREBELLAR ATAXIAS (SCAs)
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Encyclopedia Classification
Domain: Neurogenetics, Neurodegeneration, Systems Neuroscience & Decentralized Biological Intelligence (DBI)
Primary Division: Cerebellar Degeneration Disorders, Protein-Misfolding Syndromes & Motor Coordination Governance Diseases
SCF Volume: Volume CLIX — Neural Coordination Systems, Cerebellar Intelligence Architecture & Neurodegenerative Pathophysiology
Document Code: SCF-SCA-0001
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I. FORMAL DEFINITION
Spinocerebellar Ataxias (SCAs)
Spinocerebellar Ataxias (SCAs) comprise a large and genetically heterogeneous group of inherited neurodegenerative disorders characterized by progressive degeneration of the cerebellum, brainstem, spinal pathways, and associated neural networks responsible for coordination, balance, motor timing, sensory integration, and adaptive motor learning.
More than 50 genetically defined SCAs have been identified.
Major subtypes include:
SCA Type | Gene |
SCA1 | ATXN1 |
SCA2 | ATXN2 |
SCA3 (Machado–Joseph Disease) | ATXN3 |
SCA6 | CACNA1A |
SCA7 | ATXN7 |
SCA8 | ATXN8OS |
SCA10 | ATXN10 |
SCA12 | PPP2R2B |
SCA17 | TBP |
DRPLA | ATN1 |
Many SCAs result from expanded CAG trinucleotide repeats producing toxic polyglutamine proteins.
Within the SCF framework:
Spinocerebellar Ataxias represent neural coordination-governance disorders in which cerebellar intelligence systems progressively lose the ability to synchronize sensory integration, motor planning, adaptive learning, and movement execution, resulting in organism-wide coordination collapse.
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II. PRIMARY AXIOM
Core Axiom
Coordinated movement requires continuous integration of sensory information, predictive modeling, timing correction, motor execution, and adaptive feedback learning across cerebellar command architectures.
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III. SCF SCA LAW
Cerebellar Synchronization Integrity Law
Progressive ataxia emerges when cerebellar timing architectures lose the capacity to coordinate predictive motor control and adaptive correction across distributed neural networks.
SCF Interpretation
The cerebellum functions as:
- Predictive motor processor
- Error-correction engine
- Movement synchronization platform
- Adaptive learning network
- Sensorimotor integration hub
- Precision-command architecture
Degeneration transforms synchronized motor intelligence into progressively desynchronized movement systems.
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IV. ETIOPATHOGENIC CORE
Primary Molecular Driver
Neurodegenerative Coordination Failure
Pathogenic Mutation
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Protein Misfolding / Toxic Gain-of-Function
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Neuronal Dysfunction
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Purkinje Cell Vulnerability
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Cerebellar Degeneration
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Progressive Ataxia
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Central Disease Mechanism
Mutant Protein
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Protein Aggregation
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Cellular Stress
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Neuronal Degeneration
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Circuit Breakdown
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Coordination Failure
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V. NORMAL CEREBELLAR GOVERNANCE ARCHITECTURE
Normal State
Sensory Input
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Cerebellar Integration
↓
Predictive Computation
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Motor Refinement
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Movement Execution
↓
Adaptive Learning
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SCA State
Neurodegeneration
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Circuit Dysfunction
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Timing Errors
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Coordination Failure
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Movement Instability
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Progressive Disability
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VI. SCF FAULT ARCHITECTURE
Tier 1 — Primary Molecular Fault
Mutant Protein Toxicity
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Neuronal Stress
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Tier 2 — Neural Governance Failure
Purkinje Cell Dysfunction
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Cerebellar Network Instability
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Tier 3 — Communication Failure
Sensorimotor Desynchronization
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Motor Timing Errors
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Adaptive Learning Failure
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Tier 4 — Organ-Level Consequences
Ataxia
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Dysarthria
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Oculomotor abnormalities
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Gait instability
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Tier 5 — Organism-Level Outcomes
Progressive disability
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Loss of independence
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Multisystem neurodegeneration
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VII. SCF FAULT TIER MAPPING
SCF Domain | Contribution |
Connectomics Failure | Primary pathology |
Molecular Command Modeling | Cerebellar governance collapse |
Feedback Desynchronization | Motor timing instability |
Mitochondrial Communication Failure | Secondary energetic stress |
Metabolic Misalignment | Neurodegenerative adaptation burden |
Immune Learning | Neuroinflammatory contribution |
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VIII. MOLECULAR MULTI-OMICS PATHOGENESIS MAP
Genomics
Primary Findings
- ATXN1 mutations
- ATXN2 mutations
- ATXN3 mutations
- ATXN7 mutations
- CACNA1A mutations
- TBP mutations
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Proteomics
Findings
- Polyglutamine-expanded proteins
- Protein aggregation
- Proteostasis failure
- Cellular stress responses
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Neuroomics
Findings
- Purkinje-cell degeneration
- Cerebellar cortical atrophy
- Brainstem degeneration
- Spinal tract involvement
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Connectomics
Findings
- Sensorimotor network disruption
- Motor-learning deficits
- Timing-network instability
- Adaptive feedback failure
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Transcriptomics
Findings
- Altered neuronal survival pathways
- Dysregulated stress-response genes
- Synaptic maintenance abnormalities
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Immunomics
Findings
- Microglial activation
- Neuroinflammatory signaling
- Secondary neurodegenerative amplification
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Electrophysiomics
Findings
- Impaired cerebellar firing patterns
- Motor timing abnormalities
- Coordination-network desynchronization
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IX. PATHOGENESIS FLOW (SCF LOGIC)
Genetic Mutation
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Protein Misfolding
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Neuronal Toxicity
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Purkinje Cell Loss
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Cerebellar Degeneration
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Motor Coordination Failure
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Gait and Balance Impairment
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Progressive Disability
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Advanced Neurodegeneration
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X. CLINICAL PHENOTYPE ARCHITECTURE
Motor Manifestations
Major Findings
- Gait ataxia
- Limb ataxia
- Dysmetria
- Intention tremor
SCF Classification
Motor Synchronization Failure Syndrome
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Speech Manifestations
Major Findings
- Dysarthria
- Scanning speech
- Impaired articulation
SCF Classification
Communication Coordination Disorder
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Oculomotor Manifestations
Major Findings
- Nystagmus
- Slow saccades
- Ophthalmoparesis
SCF Classification
Visual-Motor Synchronization Disorder
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Cognitive Manifestations
Major Findings
- Executive dysfunction
- Processing-speed reduction
- Cognitive impairment (subtype-dependent)
SCF Classification
Adaptive Processing Dysfunction
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Systemic Manifestations
Major Findings
- Neuropathy
- Parkinsonism
- Spasticity
- Dysphagia
SCF Classification
Extended Neural Governance Failure
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XI. PATHOGENS → SYMPTOMATOLOGY → SCF FAULT TIER MAPPING
Manifestation | SCF Interpretation |
Gait ataxia | Whole-body timing failure |
Limb ataxia | Motor precision collapse |
Dysarthria | Speech coordination instability |
Nystagmus | Oculomotor synchronization failure |
Tremor | Predictive-control dysfunction |
Dysphagia | Bulbar coordination impairment |
Cognitive decline | Cerebrocerebellar network disruption |
Loss of balance | Sensorimotor integration failure |
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XII. CEREBELLAR INTELLIGENCE FAILURE ATLAS
Normal State
Sensory Feedback
↓
Predictive Processing
↓
Motor Correction
↓
Movement Precision
↓
Adaptive Learning
↓
Coordinated Function
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SCA State
Cerebellar Degeneration
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Prediction Failure
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Error Accumulation
↓
Motor Instability
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Adaptive Learning Loss
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Progressive Disability
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XIII. MOLECULAR COMMAND MODELING ANALYSIS
Tier I — Sensor Disturbance
Affected Sensors
- Proprioceptive integration systems
- Vestibular-processing pathways
- Visual-motion feedback networks
Consequence
Movement-state information becomes increasingly inaccurate.
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Tier II — Integrator Failure
Affected Integrators
- Purkinje cells
- Deep cerebellar nuclei
- Cerebellar cortical networks
- Cerebellothalamic pathways
Consequence
Motor correction algorithms deteriorate.
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Tier III — Executive Controller Failure
Affected Controllers
- Motor timing systems
- Balance-governance pathways
- Sensorimotor adaptation networks
- Predictive movement architecture
Consequence
Coordinated motor execution becomes unstable.
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Tier IV — Functional Outcome
- Ataxia
- Dysarthria
- Balance impairment
- Progressive disability
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XIV. COMMAND HIERARCHY MAPPING
Upstream Sensors
- Vestibular receptors
- Proprioceptive systems
- Visual-motion pathways
- Somatosensory networks
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Midstream Integrators
- Purkinje-cell networks
- Cerebellar cortex
- Deep cerebellar nuclei
- Cerebellar afferent pathways
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Executive Controllers
- Cerebellothalamic circuits
- Motor planning systems
- Balance-control architecture
- Adaptive learning networks
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Downstream Effectors
- Spinal motor neurons
- Oculomotor nuclei
- Speech musculature
- Limb musculature
- Postural stabilization systems
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XV. SCA BIOMARKER ATLAS
Genetic Biomarkers
Biomarker | Significance |
ATXN1 expansions | SCA1 |
ATXN2 expansions | SCA2 |
ATXN3 expansions | SCA3 |
ATXN7 expansions | SCA7 |
CACNA1A variants | SCA6 |
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Neuroimaging Biomarkers
Biomarker | Significance |
Cerebellar atrophy | Disease burden |
Brainstem atrophy | Progression marker |
Cerebellar volume loss | Neurodegeneration severity |
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Neurophysiologic Biomarkers
Biomarker | Significance |
Eye-movement abnormalities | Network dysfunction |
Gait metrics | Functional impairment |
Balance testing | Disease progression |
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Functional Biomarkers
Biomarker | Significance |
SARA score | Ataxia severity |
Speech analysis | Coordination burden |
Swallowing assessments | Bulbar involvement |
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XVI. COMMAND VULNERABILITY ANALYSIS
Highest-Leverage Nodes
Rank | Node | Functional Role |
1 | Purkinje Cell Network | Master cerebellar processor |
2 | Cerebellar Cortex | Predictive computation platform |
3 | Cerebellothalamic Pathways | Communication bridge |
4 | Motor Learning Networks | Adaptive correction system |
5 | Vestibulocerebellar System | Balance architecture |
6 | Oculomotor Coordination Network | Visual-motion synchronization |
7 | Brainstem Integration Centers | Movement execution support |
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Disease Amplification Circuit
Protein Toxicity
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Purkinje Cell Stress
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Cerebellar Dysfunction
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Motor Errors
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Reduced Adaptive Learning
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Network Instability
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Further Neurodegeneration
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Progressive Ataxia
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XVII. SCF THERAPEUTIC MECHANISMS
SCF-PCR FRAMEWORK
Preventative
Objectives
- Early diagnosis
- Preserve cerebellar function
- Delay neurodegeneration
Strategies
- Genetic testing
- Family screening
- Neurologic surveillance
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Curative
Objectives
- Slow neurodegeneration
- Preserve neural communication
- Maintain functional independence
Current Clinical Approaches
- Symptomatic management
- Physical rehabilitation
- Speech therapy
- Occupational therapy
- Multidisciplinary neurologic care
Currently, most SCAs lack disease-modifying approved therapies, though multiple gene-targeted and neuroprotective strategies remain under investigation.
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Restorative
Objectives
- Maximize adaptive function
- Preserve mobility
- Improve quality of life
Strategies
- Assistive technologies
- Balance training
- Swallowing support
- Long-term rehabilitation programs
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XVIII. PROJECT RHENOVA INTEGRATION PATHWAYS
Connectomics Failure
Primary Defect
- Cerebellar communication collapse
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Molecular Command Modeling
Primary Defect
- Predictive motor-governance dysfunction
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Feedback Desynchronization
Primary Defect
- Motor correction failure
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Mitochondrial Communication Failure
Secondary Defect
- Energetic vulnerability of degenerating neurons
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Metabolic Misalignment
Secondary Defect
- Chronic neurodegenerative adaptation burden
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XIX. SCF THERAPEUTIC RECONSTRUCTION LOGIC
Tier 1 — Cerebellar Preservation
Targets
- Purkinje-cell survival
- Circuit stability
- Protein-homeostasis restoration
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Tier 2 — Motor Re-Synchronization
Targets
- Sensorimotor integration
- Predictive processing
- Balance control
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Tier 3 — Adaptive Learning Restoration
Targets
- Motor plasticity
- Error-correction networks
- Functional compensation systems
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Tier 4 — Whole-System Coordination Resilience
Targets
- Mobility preservation
- Communication integrity
- Long-term independence
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XX. NEXT STRATEGIC RESEARCH PATHWAYS
- Cerebellar intelligence atlases
- Spinocerebellar ataxia digital twin platforms
- Polyglutamine toxicity systems biology
- Multi-omics cerebellar degeneration mapping
- Predictive motor-network analytics
- Precision progression prediction systems
- Purkinje-cell resilience modeling
- FDA-aligned neurodegenerative companion diagnostics
- Whole-brain coordination simulations
- Neural synchronization reconstruction therapeutics
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XXI. SCF SUMMARY STATEMENT
Spinocerebellar Ataxias are the SCF-defined neural coordination-governance disorders characterized by cerebellar degeneration, predictive motor-control failure, impaired adaptive learning, and progressive loss of movement synchronization. Within the SCF framework, these disorders represent collapse of cerebellar intelligence architectures responsible for integrating sensory information, correcting motor errors, and maintaining coordinated behavior. The central pathophysiologic event is degeneration of cerebellar command networks leading to progressive organism-wide coordination failure.
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SCF MASTER REGISTRY INDEX
- SCF-SCA-0001 — Spinocerebellar Ataxias
- SCF-SCA1-0001 — Spinocerebellar Ataxia Type 1
- SCF-SCA2-0001 — Spinocerebellar Ataxia Type 2
- SCF-SCA3-0001 — Machado–Joseph Disease
- SCF-SCA6-0001 — Spinocerebellar Ataxia Type 6
- SCF-SCA7-0001 — Spinocerebellar Ataxia Type 7
- SCF-CF-0001 — Connectomics Failure
- SCF-MCM-0001 — Molecular Command Modeling
- SCF-FDS-0001 — Feedback Desynchronization
- SCF-MCF-0001 — Mitochondrial Communication Failure
- SCF-MM-0001 — Metabolic Misalignment
- SCF-IL-0001 — Immune Learning
- SCF-CSDBIR-0001 — Cross-System DBI Reconstruction
- SCF-PATH-0001 — SCF Pathophysiology Protocol (Extended Version)
- SCF-RHENOVA-0001 — Project RHENOVA Integration Framework
- SCF-CIS-0001 — Cerebellar Intelligence Systems Registry
- SCF-CGA-0001 — Cerebellar Governance Architecture Registry
- SCF-PCN-0001 — Purkinje Cell Network Registry
- SCF-PMA-0001 — Predictive Motor Architecture Registry