You most certainly can, you will either need to buy a USB interface board, or look up some schematics for them and have a go at making one yourself. PIR sensors usually have a fairly straightforward output – either switched or a 5v or similar output – both of which should be easy to interface to with the appropriate board.
Ive listed a few different boards below that might give you some ideas as to what you are after – some probably have more inputs than necessary and some have both inputs and outputs, but they are all relatively inexpensive:
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