---
title: SAE Brain Semantic Interface
emoji: 🧠
colorFrom: blue
colorTo: purple
sdk: docker
pinned: false
app_port: 7860
---

# SAE Brain Explorer

Interactive explorer for Sparse Autoencoder (SAE) features with brain alignment.

## Features

- UMAP scatter of 10,000 SAE features (DINOv2 L11 Spatial)
- Click any feature to see top-activating images with heatmap overlays
- CLIP text search across features
- NSD brain dataset: same features viewed through 34K natural scene images
- Phi-based brain alignment: which features are most predictive of fMRI activity
- Cortical map visualization

## Data

- **SAE**: DINOv2 L11 Spatial, d=10,000, k=100
- **Images**: COCO val2017
- **Brain**: NSD sub01 fMRI aligned to SAE features via Phi regression

## Environment Variables (set in Space settings)

| Variable | Required | Description |
|---|---|---|
| `HF_DATASET_REPO` | Yes | HF dataset repo ID, e.g. `username/sae-nsd-data` |
| `HF_TOKEN` | If private | HF read token for the dataset repo |
| `GOOGLE_API_KEY` | No | Enables Gemini-powered auto-labeling |