This sometimes happens to me if I am not in the mood, need to be doing something else, or if the book is badly written. Some text books need to be read with con

This sometimes happens to me if I am not in the mood, need to be doing something else, or if the book is badly written. Some text books need to be read with concentration. But if something is good, it is more like a trance - I'll 'come to' hours later and need to be prodded with a stick if you want to interrupt me.