What were the only things in which Elie took interest in chapter 4 of "Night"?

The narrator tells us that he "took little interest in anything except my daily plate of soup and my crust of stale bread" (63).  This is consistent with Maslow's hierarchy of needs, which tells us that we are not able to care about anything unless our basic needs for food and shelter are taken care of.  The narrator has shelter, so he is reduced to his most basic need of food. He is no longer really a person at all, and describes himself as "a body," or perhaps "a starved stomach (63), meaning that he cannot care about anything except the food he needs to survive.