diff --git a/src/physics/arcade/Factory.js b/src/physics/arcade/Factory.js
index 9edd71047..97a501140 100644
--- a/src/physics/arcade/Factory.js
+++ b/src/physics/arcade/Factory.js
@@ -65,9 +65,9 @@ var Factory = new Class({
      *
      * @param {Phaser.Physics.Arcade.Body} object1 - The first object to check for collision.
      * @param {Phaser.Physics.Arcade.Body} object2 - The second object to check for collision.
-     * @param {ArcadePhysicsCallback} collideCallback - The callback to invoke when the two objects collide.
-     * @param {ArcadePhysicsCallback} processCallback - The callback to invoke when the two objects collide. Must return a boolean.
-     * @param {*} callbackContext - The scope in which to call the callbacks.
+     * @param {ArcadePhysicsCallback} [collideCallback] - The callback to invoke when the two objects collide.
+     * @param {ArcadePhysicsCallback} [processCallback] - The callback to invoke when the two objects collide. Must return a boolean.
+     * @param {*} [callbackContext] - The scope in which to call the callbacks.
      *
      * @return {Phaser.Physics.Arcade.Collider} The Collider that was created.
      */
@@ -84,9 +84,9 @@ var Factory = new Class({
      *
      * @param {Phaser.Physics.Arcade.Body} object1 - The first object to check for overlap.
      * @param {Phaser.Physics.Arcade.Body} object2 - The second object to check for overlap.
-     * @param {ArcadePhysicsCallback} collideCallback - The callback to invoke when the two objects collide.
-     * @param {ArcadePhysicsCallback} processCallback - The callback to invoke when the two objects collide. Must return a boolean.
-     * @param {*} callbackContext - The scope in which to call the callbacks.
+     * @param {ArcadePhysicsCallback} [collideCallback] - The callback to invoke when the two objects collide.
+     * @param {ArcadePhysicsCallback} [processCallback] - The callback to invoke when the two objects collide. Must return a boolean.
+     * @param {*} [callbackContext] - The scope in which to call the callbacks.
      *
      * @return {Phaser.Physics.Arcade.Collider} The Collider that was created.
      */