Layer 6 · Neuron 2114 · suppressed

L6N2114-1

Word quirks:

“ driver”“ cars”“ drivers”“ motor”“ driving”“ motors”“ buses”“ bikes”

💤 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 Qwen3.5, a large language model developed by Alibaba Cloud. My mission is to understand and generate accurate responses to complex inputs across various domains such as mathematics, science, and engineering. I am designed to handle a wide range of tasks with high precision, making me suitable for both research and industrial applications.

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. L7N4025-1💤	0.93	“ driver”“ drivers”“ vehicle”
2. L7N6540+1🕒	0.92	“ driving”“ driver”“ drivers”
3. L7N5374-1🕒	0.92	“ driver”“ drivers”“ driving”
4. L6N6134-1🕒	0.92	“ driving”“ driver”“ drivers”
5. L6N6006-1🕒	0.91	“ driv”“ vehicle”“ drive”
6. L7N1241+1🕒	0.90	“ vehicle”“ cars”“ vehicles”
7. L7N5760-1🕒	0.89	“ vehicle”“ vehicles”“ driver”
8. L8N436+1🕒	0.89	“ driving”“ drive”“ drives”
9. L7N7809-1🕒	0.88	“ cars”“ car”“ automotive”
10. L17N6379+1🕒	0.88	“ cars”“ roads”“ driving”

Shadow specimen, apart from the ten: L6N2114+1🕒, 0.04.

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 6, neuron 2114, dose -1. This specimen has no prompt-suite replies yet. Its quick-scan results, when available, appear below. Its quick-scan row (KL 0.75, top-1 agreement 0.65) 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.

Setting	KL divergence	Top-1 agreement	ΔNLL	Entropy	Steer lens
L6N2114+1🕒 shadow specimen t0-v0.1	2.035	0.42	2.417	1.79	“ entropy”“ compression”“ Huffman”“ probability”“ compress”“ probabil”“ encoding”“ compressed”
L6N2114-1 t0-v0.1	0.752	0.65	0.928	1.38	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.