Whole Brain Emulation

The Concept

Whole brain emulation (WBE), often called "mind uploading," is the hypothetical process of scanning a biological brain at sufficient resolution to capture its complete structure and state, then simulating that structure on a computer so that it runs as the original brain did—including generating consciousness and subjective experience.

If successful, WBE would create a digital mind indistinguishable from the original person—a copy that thinks, feels, and remembers exactly as the biological version did at the moment of scanning.

Technical Requirements

The FHI's Whole Brain Emulation Roadmap identifies several prerequisites:

Scanning technology: We need to capture the brain's complete structure—not just neurons, but synaptic connections, their strengths, neurotransmitter concentrations, and other relevant details. Current techniques like electron microscopy can achieve sufficient resolution but are destructive and extremely slow.

Neuroscience understanding: We must know which features of neural structure are computationally relevant. Do we need to simulate individual protein interactions, or is neuron-level modeling sufficient?

Computational resources: A human brain has roughly 86 billion neurons with 100 trillion synaptic connections. Simulating this in real-time requires enormous compute—though estimates vary widely based on the required level of detail.

The Path Forward

Two main approaches exist:

Destructive uploading: Slice the brain into thin sections, scan each at nanometer resolution, reconstruct the complete connectome. This works only after death (or causes it).

Non-destructive uploading: Develop scanning technology that can read brain structure without destroying it. Much harder technically but preserves the original.

Some speculate that gradual neuron replacement could achieve the same result—replacing biological neurons one by one with artificial equivalents until the entire brain is synthetic, with no single moment of "uploading."

Philosophical Questions

WBE raises profound questions about consciousness and identity:

The copy problem: If you upload, is the digital version really "you"? The original body might still exist (in non-destructive scenarios). Are there now two of you?

Consciousness: We don't know if consciousness can exist in silicon. A perfect functional replica might be a "zombie"—behaving like a conscious being without inner experience.

Identity continuity: Is there meaningful continuity between the biological original and digital copy? Or does the original die while a copy continues?

Multiplicity: If you can run as software, you can be copied. What happens to identity when there are thousands of you?

These aren't just philosophical puzzles—they have practical implications for whether WBE actually achieves its goal of extending your life versus creating something new that merely resembles you.