Deep Eye Sockets
If your subject has dark eye sockets, press Command-J (PC: Ctrl-J) to duplicate the Background layer, then change the layer blend mode to Screen to brighten the entire image. Option-click (PC: Alt-click) the Add Layer Mask icon (circle in a square) to hide this brighter layer behind a black mask. Press D to set your Foreground color to white; choose a small, soft-edged Brush (B); then paint over the entire eye-socket area to brighten that area. Now, lower the layer Opacity until the brightening matches the surrounding skin.
by Scott Kelby