concept
archived
concept:addition-module

Addition module

Specific neural circuitry in layer 18 of Llama-3.1-8B that performs arithmetic and cyclic reasoning.

Neighborhood — ranked by edge-count

Related by similarity (8)

cosine ≥ 0.65 · no typed edge

Entities in the same semantic neighborhood but without a typed relation to this one — candidates for new edges or unrecognized duplicates.

  • Modular additionconcept0.853
    The mathematically natural computation for cyclic concepts (e.g., addition mod 12 for months), which the paper shows Llama does NOT directly implement
  • Intervention method that adds a learned direction vector to residual stream activations to steer model behavior
  • Base-10 additionconcept0.788
    The generic addition mechanism that Llama-3.1-8B actually uses to compute sums before mapping back to cyclic concept space
  • Steering method deriving vectors from contrastive prompt pairs and adding to first-token activations.
  • The core finding: Llama-3.1-8B reuses one addition mechanism across all cyclic tasks rather than learning task-specific modular arithmetic
  • Independent, parallel cognitive subsystems that share information via a global workspace.
  • Method formalized by Rimsky et al. (2024) that this paper adopts for extracting persona vectors
  • Adding steering vector in forward direction to push model activations toward stronger reflective behavior.