diff --git a/rastermap/rastermap.py b/rastermap/rastermap.py
index e7a4b12..dba0d27 100644
--- a/rastermap/rastermap.py
+++ b/rastermap/rastermap.py
@@ -44,7 +44,7 @@ def highd_settings():
     settings = default_settings()
     settings["n_clusters"] = 100
     settings["n_splits"] = 3
-    settings["nPCs"] = 400
+    settings["n_PCs"] = 400
     return settings
 
 
diff --git a/tests/test_rastermap.py b/tests/test_rastermap.py
index 83aa148..7d9d360 100644
--- a/tests/test_rastermap.py
+++ b/tests/test_rastermap.py
@@ -1,5 +1,19 @@
+import inspect
+
 import numpy as np
 from rastermap import Rastermap
+from rastermap.rastermap import default_settings, sequence_settings, highd_settings
+
+
+def test_settings_are_valid_kwargs():
+    valid = set(inspect.signature(Rastermap.__init__).parameters) - {"self"}
+    for settings in (default_settings, sequence_settings, highd_settings):
+        unknown = set(settings()) - valid
+        assert not unknown, f"{settings.__name__} returns unknown keys: {unknown}"
+
+
+def test_highd_settings_n_PCs():
+    assert highd_settings()["n_PCs"] == 400
 
 
 def test_rastermap(test_file):