to jog someone's memory
to help someone remember something: "You don't remember who was with us that day? Here's a photograph to jog your memory."
to rack your brain
to try very hard to remember something
a trip down memory lane
when people think about and remember things from the past
off the top of your head
not a carefully considered opinion often because of a lack of time to check the accuracy of the information
a senior moment
to have a lapse in memory, usually unexpectedly
slip my mind
to forget something
on the tip of my tongue
a word or name that you can almost remember but not quite - it's just out of reach
to bear something in mind
to remember something important: You must bear in mind that the cost of living is higher in New York."
food for thought
something that makes you think about something deeply
have (something) on the brain
If you have something on the brain, you think or talk abut it all constantly. "Stop talking about golf. You've got golf on the brain!"
ring a bell
If something rings a bell, it sounds familiar, but you don't remember the exact details. "John Bentley? The name rings a bell but I don't remember him."
refresh someone's memory
remind them about the things they have forgotten: "Let me refresh your memory - you've already missed three classes this term."
miles away
unaware of what is happening or what someone is saying
a blast from the past
a person or thing that reminds you of an earlier time in the past
a memory like a sieve
a really bad memory
if my memory serves me well
if I remember correctly, have not forgotten any details
go in one ear and come out the other
"I keep telling him about the risks but it goes in one ear and out the other. He never listens!"
lose your train of thought
to forget what you were saying because of an interruption: "Now what was I telling you? I'm afraid I've lost my train of thought."