Neuron Depolarization Process

Depolarization Process

• Neurons have a resting membrane potential of approximately -70mV, where the inside of the cell is negatively charged compared to the outside.
• When a neuron is stimulated, ion channels in the cell membrane open, allowing ion movement.
• Sodium (Na+) ions rush into the neuron, causing an influx of positive charge.
• The influx of Na+ ions leads to depolarization, which is the change in membrane potential towards a more positive state.
• If the depolarization reaches a certain threshold, it triggers an action potential.

Action Potential

• The action potential is an all-or-nothing response that travels down the length of the axon.
• The action potential leads to the release of neurotransmitters at the synapse.

Depolarization

• Neurons have a resting membrane potential of around -70mV, with the inside of the cell being negative compared to the outside.
• When a neuron is stimulated, ion channels in the cell membrane open, allowing sodium (Na+) ions to rush in.
• The influx of Na+ ions causes the membrane potential to become more positive, and if it reaches a certain threshold, it triggers an action potential.
• The action potential is an all-or-nothing response that travels down the axon, leading to the release of neurotransmitters at the synapse.

Repolarization

• During an action potential, the membrane potential becomes more positive due to the influx of sodium (Na+) ions.
• After the peak of the action potential, potassium (K+) channels open, allowing K+ ions to flow out of the cell and restore the negative membrane potential.
• The membrane potential returns to its resting state, around -70mV, through the combined action of K+ outflow and the Na+/K+ pump, which restores the original ion concentration gradients.

Hyperpolarization

• During hyperpolarization, the inside of the neuron becomes more negative compared to the outside due to the movement of potassium (K+) ions out of the cell or chloride (Cl-) ions into the cell.
• Voltage-gated potassium channels open, allowing K+ ions to leave the cell, making the inside more negative.
• Sometimes, chloride channels open, allowing Cl- ions to enter the cell, contributing to the negative charge inside.
• Hyperpolarization makes it less likely for a neuron to fire an action potential because the membrane potential moves further away from the threshold needed to trigger an action potential.