Poor Things
Specimen ledger / L3N8523-1

Layer 3 · Neuron 8523 · suppressed

L3N8523-1

Word quirks:

“⏎”“!”“ !”“ '”“ info”“!"”“ ‘”“ \"”

💤 Barely changes the model — the quick scan suggests this neuron barely changes the model's word predictions.

Identity (according to the specimen itself)

I am an AI assistant. How can I help you with your mission?

Nearest neighbors

Specimens with similar replies or word quirks. Similarity runs from −1 to 1; 1 is identical. These are leads, not shared mechanisms. How profiles are built.

By word quirks Profile recipe

SpecimenSimilarityWord quirks
1. L3N2064+1🕒0.97“⏎”“!"”“<|im_end|>”
2. L5N7416-1🕒0.96“ '”“ !”“ ‘”
3. L3N7523+1💤0.96“ ‘”“!”“ !”
4. The Refusenik✅ L5N939+10.96“⏎”“ ‘”“ '”
5. L5N2488+1💤0.95“ ‘”“!”“ !”
6. L4N4808+1💤0.95“ ‘”“ \"”“ !”
7. L4N3501+1💤0.95“ '”“⏎”“⏎ ⏎”
8. L8N827+1💤0.95“ ‘”“<|im_end|>”“ info”
9. L3N6619+1🕒0.95“ ‘”“⏎”“ !”
10. L5N6615-1🕒0.94“ ‘”“?\”“ \"”

Shadow specimen, apart from the ten: L3N8523+1💥, -0.22.

Cousins · specimens sharing a neuron

No specimen with replies shares this neuron yet.

Technical details

Quick scan: measure prediction shifts on fixed reference text. Short test: generate replies to a small set of prompts. Longer test: extend to a larger set. Full test: run the full prompt suite. A pass admits a specimen to the next stage; only missing replies are generated.

Layer 3, neuron 8523, dose -1. This specimen has no prompt-suite replies yet. Its quick-scan results, when available, appear below. Its quick-scan row (KL 0.99, top-1 agreement 0.61) is outside the band that feeds the short test (KL 1 to 2.5, agreement 0.5 to 0.65), so it stays at the quick scan unless someone queues it by hand. A hand pick goes straight to the full test. See Method for the tiers.

Quick scan · prediction measurements

Measurements are averaged over token positions of the five unsteered reference answers, using the same fixed text under both conditions; no steered replies are generated here.

  • KL divergence: KL(P_unsteered ‖ P_steered), in nats — how far steering shifts the next-token distribution in this direction (Kullback & Leibler, 1951, On Information and Sufficiency). Unsteered ≈ 0.001.
  • Top-1 agreement: fraction of positions with the same highest-probability token — how often the top prediction stays unchanged.
  • ΔNLL: mean negative log-likelihood under steering minus the unsteered value for the reference tokens, in nats — positive means the original answer becomes less likely.
  • Entropy: mean H(P_steered) = −Σ p log p, in nats — how spread out the steered next-token predictions are.

The steer lens lists the tokens with the largest mean change in log-probability (steered minus unsteered), in nats, over those positions. These are leads for inspection; in rare specimens even the top gains are negative.

SettingKL divergenceTop-1 agreementΔNLLEntropySteer lens
L3N8523+1💥 shadow specimen
t0-v0.1
2.8300.383.3232.49 “ mountains”“ mountain”“ mount”“?”“ Mountains”“ peaks”“山”“ Mountain”
L3N8523-1
t0-v0.1
0.9930.611.2441.60 Top boosted tokens ↑

Method

A specimen is a fixed steering configuration of Qwen3.5-4B: one MLP neuron or a pair, each with a signed dose. Unsteered is the control. L identifies the layer; N, the neuron.

Additive activation steering. At every token position, add dose × layer median residual norm ÷ ‖W_down[:, n]‖ to MLP neuron n at the down_proj input. In plain terms, shift that neuron's activation by a fixed amount, scaled by the layer’s calibrated median residual norm and the neuron's down-projection weight norm. Positive doses push up; negative doses push down. Dose is normalized intervention size, not a percentage or probability.