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📊 Electrophysiology
Long-Term Voltage Trace
Oscilloscope (100ms window)
Compartmental Voltages
🔬 Membrane Patch
Axon Hillock - Molecular Scale (~200nm × 200nm)
-70mV
-90 -55 (threshold) +40
Resting State
Scale ~7nm membrane thickness
Na⁺ Channels Open 0 / 8
K⁺ Channels Open 0 / 6
Na⁺/K⁺ Pumps Active 2 cycling
ATP Available 12
Ion Concentrations
Extracellular
Na⁺: 145 mM
K⁺: 5 mM
Cl⁻: 120 mM
Intracellular
Na⁺: 15 mM
K⁺: 140 mM
Cl⁻: 10 mM
Membrane Regions
← SOMA (left)
Few voltage-gated channels
AXON HILLOCK (right) →
High Nav/Kv density
AP initiation zone
🎨 Legend
Phospholipid
Cholesterol
Nav Channel (closed)
Nav Channel (open)
Kv Channel (closed)
Kv Channel (open)
Na⁺/K⁺-ATPase
Na⁺ ion
K⁺ ion
ATP molecule
ADP (spent ATP)
S4 Voltage Sensor
🖱️ Drag to rotate membrane • Scroll to zoom • Click channels to toggle • Flip view to see intracellular side

⚙️ Controls

⚡ Action Potential

Membrane Voltage -70 mV

🧠 Synaptic Input

E/I Balance 1.0 (balanced)
← More inhibition | More excitation →
Spontaneous EPSP Rate 5 Hz
Spontaneous IPSP Rate 1 Hz

📊 Recording Setup

Recording Mode
Sharp electrode pierces membrane to record intracellular voltage directly.
Use Hodgkin-Huxley Model
Full biophysical simulation

🧬 Simulation Speed

Time Scale 1x (real-time)
Slower ← → Faster (real molecular timescale: μs)
Brownian Motion Intensity 100%

🔬 Visualization

Show Lipid Tails
⚠️ Performance impact when enabled
Show Water Molecules
Lipid Density 100%
Membrane Flexibility 70%

🧪 Channel Properties

Nav Activation Threshold -55 mV
Nav Inactivation Rate 100%
Kv Activation Delay 1.0 ms
Pump Rate (ATP/sec) 100
Biophysical Model:
• Hodgkin-Huxley kinetics
• Nernst/GHK equations
• 3 compartments (soma→hillock→axon)
• Local circuit current spread

Equilibrium Potentials:
• ENa = +60 mV
• EK = -90 mV

Synaptic:
• EPSP → depolarization
• IPSP → hyperpolarization
• E/I balance controls firing rate
FPS: 60
Lipid Count: 0
Ion Count: 0
Sim Time: 0.00 ms