During imprisonment, the prisoners experience many physical, emotional, and spiritual changes as they are forced into inhumane conditions for a longer period of time as the story progresses.

Chapters one through five of the memoir have much more length and description. Wiesel is careful to give the background of his life before Auschwitz as well as what the "settling in" process was like in great detail. Also, the overall sense of familial duty and bonds in general is obvious in these chapters. There are several mentions of people asking after their loved ones, and the reader sees Wiesel and his father become closer and protective of each other. Wiesel even mentions forming friendships with some of the people with whom he works.

In some sense, chapter five is the chapter that ultimately shifts the memoir. Although it possesses the long descriptions typical of the first half, it also contains much darker images and the first glimpses of the need for individual survival.

However, chapter six is where is the difference is especially clear. One shift that occurs in the latter half of the memoir is the physical presence of death. Chapter six, specifically, is an excellent example of this, as Wiesel describes death as a visceral form that steals life from the bodies during the Death March. Additionally, chapters six through nine depict a loss or at least a wearing down of the bonds that were created in the first half of the memoir. Wiesel's friend, Juliek, dies from being essentially suffocated by other prisoners. Wiesel begins to think of his father as a burden. Several other sons leave their fathers behind as they themselves push to live. These experiences are why Wiesel states at the end of the memoir that he truly doesn't recognize himself when he sees himself in the mirror after liberation. He has not only changed physically, but his inner being has morphed into something that he sees as almost inhuman.

The physical and emotional transformation of the prisoners is significant from the first half of the book to the last half of the book.

In the first half of the book the prisoners, Elie included are struggling to cope with their torturous plight in life. They struggle with their faith, beliefs, spirituality. They care about what happens to each other. Elie's language in the first half of the book is much more philosophical. He contemplates his own deeply rooted spirituality. We see him transform from a "deeply observant" twelve, almost thirteen year old into an adult who was robbed his childhood by the Nazis. He loses his family, his life, he questions God, and he learns to hate the Nazis.

In the last half of the book the prisoners transform from humans who have the wherewithal to discuss their faith and share camaraderie to humans that are in their most basis animal form operating solely on instinct for food and survival. Elie personifies death in chapter 6 because it is apparent for everyone. He write, "Death, which was settling in all around me, silently, gently. It would seize upon a sleeping person, steal into him and devour him bit by bit." In Chapter 7 Elie witnesses a man kill his own father for a crust of bread! The man was driven by his hunger and fight for survival that he did not even hear when his father begged for his life. The last half of the book is the final fight for survival.