diff --git a/src/math/Quaternion.js b/src/math/Quaternion.js
index ae66f9e2203a862ecfd9afde9c258bb53643a4e3..48a78a8f5b482b7698e1a89771f70b3d1a13e0fe 100644
--- a/src/math/Quaternion.js
+++ b/src/math/Quaternion.js
@@ -562,7 +562,10 @@ Object.assign( Quaternion.prototype, {
 			this._y = s * y + t * this._y;
 			this._z = s * z + t * this._z;
 
-			return this.normalize();
+			this.normalize();
+			this._onChangeCallback();
+
+			return this;
 
 		}