Here is the full list of all 20 Paranormal State: Poison Spring achievements. It takes around 3-4 hours to unlock all of the achievements on Windows.
Finish a Hidden Object scene in less than 1 minute.
Finish 3 Hidden Object scenes in a row without a hint.
Find 20 wolves.
Finish a minigame without skipping.
Finish 3 minigames in a row without skipping.
Finish a total of 10 minigames.
Finishing a Hidden Object scene without a hint.
Use the EMF meter.
Use the CAM.
Finish a Hidden Object scene in less than 3 minutes.
Use the EVP recorder.
Complete the main story.
Escape the haunted trailer.
Escape the basement.
Complete the Talking Stick.
Discover the Old Zeb.
Escape the excavation pit.
Draw your own map.
Enter the ritual cave.
Finish a total of 10 Hidden Object scenes.