Communication Between Two Neurons

Introduction

• Topic: Communication between two neurons.
• Importance: Understanding neuron communication is fundamental to understanding all brain functions and behaviors.

Parts of a Neuron

• Cell Body (Soma): Performs general maintenance, absorbs nutrients, and oxygen.
• Axon: Transmits information.
• Dendrites: Receive information, full of receptor sites.

Basic Neuron Communication

• Neurons are connected by axons, forming circuits.
• Groups of neurons firing together create thoughts, actions, feelings, etc.

Synaptic Transmission

• Presynaptic Neuron: Transmits information.
• Postsynaptic Neuron: Receives information.
• A neuron’s designation as pre or post-synaptic is relative based on its relationship with other neurons.

The Synapse

• Synapse: The gap between terminal buttons and dendrites where the neurotransmitter is released.
• Neurotransmitters communicate information across the synapse.

Neurotransmitters

• Chemicals like dopamine, serotonin, norepinephrine.
• Stored in vesicles in terminal buds.
• Released when electrical signals reach the axon terminal.

Action Potential

• The trigger of electrical signals that travel down the axon.
• Described as an "All or Nothing" event.

Excitatory and Inhibitory Inputs

• Excitatory Synaptic Input: Increases likelihood of firing (e.g., glutamate).
• Inhibitory Synaptic Input: Decreases likelihood of firing (e.g., GABA).

Reuptake

• Process of presynaptic cells taking back neurotransmitters.
• Important for recycling neurotransmitters.
• Some drugs block reuptake to increase neurotransmitter availability.

Neural Networks

• Groups of interconnected neurons forming circuits.
• Fundamental for sensations, thoughts, actions, and bodily functions.

Brain Plasticity

• Synaptic/Neuro Pruning: The elimination of unused neural connections.
• Neurogenesis: Formation of new neurons.
• Brain adapts through experience, forming new networks or modifying existing ones.
• Encouraged to learn new skills to prevent cognitive decline.

Conclusion

• Understanding neurons and their communication is crucial to understanding brain functions.
• Brain plasticity allows for continuous learning and adaptation.