mind that discovered themost for us, is least discovered.

the mind has discovered the most for us. but it has been neglected the most. we know little about the mind. mind means thoughts , memories , process charts , the control station for body , what exactly is mind. 

i have been meditating for years and the mind is the subject matter for meditation. the thoughts come to the mind probably for these reasons, 
interests,
concerns,
emotions,
external factors.
what controls the thoughts are narrated in these factors. so if you are interested in cricket match the thoughts will cloud around this. the memories will be clear on this subject.
and you fear about failure in an job interview the mind will precipitate most about the failures into your mind at the time of interview. it will be a fearsome battle to bury these thoughts and freely attend the interview. so when you want to control failure thoughts it is advised that you neglect these thoughts , just forget about the failure or these thoughts will overshadow all other thoughts in your mindspace. thats how the mind works. you want to control a thought and you are concern about it and the mind starts thinking about it more and more and you can not just do away with the thought you want to control. thought may an emotion. 
i have experienced this during my meditation. it is advised to all meditation practitioners that a calm atmosphere is required , this become the concern while meditation. the more peace you think , the more the sounds and disturbances come to your mind. you think about the silence as requirement , a pindrop will start disturbing you , (which otherwise is not even heard ), to overcome this , i started meditation just before my tv set with full sound and with a program that is irritating to me. after some time , it was a miracle that i was able to meditate even in this condition. thats how the mind works. now any sound does not disturb me. 
now let me come back to the basic question , what is the route cause of mind thoughts. what triggers the interests, concerns, emotions , specially when you are meditating. you do not have any external factors also. some unconnected thought pops up into your mind. and you wonder what made this thought to come to your mind and at this point of time. is it the 
chemical reactions
body requirements
cultures and previous thoughts
what is the controlling station. 
thats where the subject becomes the sukshma from the sthoola. it has been the incessant follow through of the thoughts but this does not end anywhere , exactly what makes a thought lets call it interest , concern become the centre point into our mind at a certain point of time. it is said that interest makes the thoughts pop up, but interest in itself is a thought or the collection of thoughts , what triggers a particular interest come to the center stage is not known. it is not known what makes it to come to center stage at a particular point of time irrespective of external factors as well as the internal memories.

moreover what makes these thoughts to go away, is also not known. suddenly you find that they are gone and a different set of thoughts has taken over your mindspace. many a times even you try very hard to remember something it just does not come to your attention. you have everything interests, concerns, external factors, emotions just everything as fuel but the mind engine just does not ignite. you grope very hard to find the right button but it just does not work. 

forgeting is as intriguing as the remembrance.   


it is difficult to understand that the processes are different for forgeting and remembering. 


i have tried the link methods and map methods of memories. but sometimes only sometimes nothing works. 


there are some other issues about mind, like sleep and dream.