many option books talked about that.
when the market is very fuctuated, the time value will go up, thus pusing the option to higher price
when the market is not fucturated, the time value will go down, thus pusing the option to lower price.
when the option is closed to exp date, the time value will go down faster
when the option is not popular (the volume is low), the time value will not go up too much
hope that helps