Frame 312. Right side of JFK’s head is in the shade.
Frame 315 : Front right part of head gone, bright white spot appears in cloud of blood spray.
Frame 317 : Very bright spot on shaded side of JFK’s head. Reflections don’t occur in the shade.
Frame 319 : Head lurching back violently. Bright spot on shaded side of JFK’s head is much brighter than anything else in the area.
The bright spot is not a reflection. It is luminescent. The only explanation I can think of is an incendiary bullet lodged in his skull.