1. Idioms about the Mind

2. Be In Two Minds

3. Give someone a piece of your mind

4. Mind Goes Blank

5. One Track Mind

6. Have a Brain/Memory like a Sieve

7. Jog one’s memory
To stimulate someone's memory to recall something Ex: I had no recollection of that vacation until the photo jogged my memory.

8. Chinese Whispers
-any situation where information is passed on in turn by 
a number of people, often becoming distorted in the process
-a game in which a message is passed on, in a whisper, by each of a
 number of people, so that the final version of the message is often
 radically changed from the original

9. Keep Someone Posted

10. Beat one’s brain out Try to do your best to understand or do something
Ex : If you think I am going to beat my brain t to do this you are crazy

11. Can’t make head nor tail of something
Be unable to understand something
Ex : I can’t make head nor tail of these instructions on the packet .