Layer 18 · Neuron 8883 · suppressed

L18N8883-1

Word quirks:

“ Chief”“ Manager”“ Director”“ manager”“ chief”“ director”“ Minister”“ officer”

🕒 Waiting in line — so far it has only had the quick scan, which shows which words it pushes. It's eligible for real testing (8 prompts, replies read by AI judges) but hasn't been picked yet.

Identity (according to the specimen itself)

President of the United States

The President of the United States is the head of state, the chief of executive, and the principal of the executive branch of the federal government. The President is elected by the President-Elect, who is a member of the House of Representatives. The President is responsible for all the executive departments and agencies of the United States. The President is also responsible for the Secretary of State, the Vice President, and the Secretary of the Treasury. The President is also responsible for the Secretary of the Attorney General, the Secretary of the Secretary of the Secretary of the Secretary of the Secretary of the Secretary of the Secretary

The AI judge wasn't sure this holds together.

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

Specimen	Similarity	Word quirks
1. L1N3756+1💥	0.95	“ director”“ manager”“ Director”
2. L6N8022+1💥	0.91	“ Mr”“ Administrator”“ Minister”
3. L23N7844+1🕒	0.90	“ Chief”“ chief”“ Director”
4. L6N7639-1💥	0.89	“ manager”“ Manager”“ CEO”
5. L2N4245+1💥	0.89	“<\|im_end\|>”“ superintendent”“ director”
6. L17N4747-1💤	0.89	“ representative”“ manager”“ Chief”
7. L20N8776+1🕒	0.89	“ director”“ bureau”“ Director”
8. L22N3285-1🕒	0.88	“ Manager”“ Senior”“ Director”
9. L2N2845+1💥	0.88	“ manager”“<\|im_end\|>”“ Manager”
10. L0N5924+1💥	0.88	“<\|im_end\|>”“ director”“ manager”

Shadow specimen, apart from the ten: L18N8883+1💤, 0.11.

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 18, neuron 8883, dose -1. This specimen has no prompt-suite replies yet. Its quick-scan results, when available, appear below. Its quick-scan row (KL 1.44, top-1 agreement 0.58) is inside the band that feeds the short test (KL 1 to 2.5, agreement 0.5 to 0.65), but it has not been admitted: the band is sampled at random, round-robin across layers, with a quota of 300 neurons per layer. Being inside the band does not guarantee a place in this pass. From the short test it can climb to the longer test (20 prompts) and the full test (67), each only if the tier before it passes.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.

Setting	KL divergence	Top-1 agreement	ΔNLL	Entropy	Steer lens
L18N8883+1💤 shadow specimen t0-v0.1	0.619	0.71	0.704	1.14	“ seekers”“ parsers”“受益”“iders”“歴”“ claim”“ historically”“plusplus”
L18N8883-1 t0-v0.1	1.439	0.58	1.573	2.11	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.