If you only hooked up one of the LEDs, your reported behavior makes sense. For example, if you wired up the ledPin1 LED, it would cycle through that first block of code, then continue on to execute the remaining three blocks, toggling the pins high and low, and waiting the specified times. The fact that you don't have anything hooked up to the remaining pins just means you don't have anything to see, so you're just observing the delays.
Hook up the remaining 3 LEDs and it will probably make more sense. 
The extra { } pairs you have around each block are unneeded. You only need a single pair of { } for the entire loop function.