nahman tulchiner was a student of Rav Natan who was a student of Rav Nahman of Breslov. He wrote down the talks of Rav Nathan and printed them. That became the "Collection of Halachot". He used to repeat softly to  himself under the words that Rav Nathan was saying so a to help him concentrate, [I also have found this idea to be helpful when I am listening to a lecture]