Laser Pointer

Our lab mix, Riley, goes crazy over the laser pointer.  She loves chasing it across the floor or around the yard.  It is so bad that you can't even pull out a flashlight with her thinking she is going to play.  Last night hubby was playing laser with her when we noticed she acted differently depending on how close the laser dot was to her.  When it was a foot or more from her, she wagged her tail and was watching the laser, but wasn't extremely focused.  When the laser got less than a foot from her, her whole body would become extremely still and you could not break her focus on the laser.  Occasionally she would try to bite at it, but she still hasn't caught on to the fact that she can't catch the laser.