In what ways is Eliezer "a corpse" at the end of the book Night?

Night is a memoir written by Eliezer Wiesel, describing his experiences in the concentration camps of Nazi Germany. Wiesel was taken as a prisoner and sent to the Auschwitz and Buchenwald camps because he and his family were Jewish.

At the end of the book- the end of his time in the concentration camps- Wiesel is quite nearly a corpse. He has been starved and worked very hard, resulting in dramatic weight loss. Most people who were sent to concentration camps were starved to death, and those that survived the lack of food and hard labor suffered health problems. There are photographs of some of the people who were rescued from concentration camps, and if they were not standing on their own two feet, you might mistake them for dead. The prisoners of the camps, Wiesel included, were not much more than skin and bones, kept alive for the purposes of labor and extended suffering.

On a more emotional level, Wiesel felt robbed of his humanity. Trauma has a nasty way of making people feel inhuman. What is it that makes us people and sets us aside from a corpse? Is it a heartbeat? The presence of brain activity? Or is it our experiences and emotions which set us apart? The people in concentration camps were denied their humanity and the rights owed with that recognition. The extreme circumstances they were forced to live (and die) under were an external denial of humanity, but had the result of an internal incapability to feel or care about anything other than basic survival. When people undergo starvation, instinct takes over and the brain begins to focus on little other than food. The feelings of happiness, sadness, excitement all come to revolve around food for the duration of the starvation. To be reduced down to our most basic instinct of eating can make us feel we are not much more than a body. Extreme stress, like starvation, can make us feel like we are lacking in the humanity that sets us apart.

Elie Wiesel likening himself to a corpse quite succinctly describes the physical, social, and psychological effects of his prolonged trauma.