I have a digital slr does anyone know why light parts on my photos flash black in the lcd monitor?

camera Nikon d40

with some cameras if you take a picture from the wrong angle and get the glare from the sun in the picture it can overcompensate and turn the light dark. try taking the same picture from different angles if it still happens even with the sun behind you take it to a specialist as this should not happen.

You have your display set to show highlights. Highlights (note the blinking areas aren't necessarily completely overexposed but are 'near').

You can move the display to show just the Folder, File name, Image size, Image quality buy pressing the < - > while viewing your image until you get to the display you want.

dont panic about it, my Canon EOS 20d does the same thing. small flashing black blochis appear on the lcd monitor on a photograph. i dont know why it does it, but its nothing to worry about. my camera is 4 yrs old and it has always done it. not a problem.
this will help