What is the author's tone in Animal Stories by Jason Brown?

The tone of the story, narrated in the first person by Jamie, comes across as flat and almost emotionless, even though the subject matter is full of sadness and suffering. Jamie appears the most emotional at the very beginning of the story, when he says that he "drove like a lunatic" to get to his mother's bedside and that he is known for "erratic bursts of self-destructiveness and unpredictable lapses in concentration." After that, he describes his rather painful life with a relatively unemotional quality. For example, when his mother displays evidence that her brain is not working correctly, his response is to calmly help her relearn how to use a television remote or to gently remind her that she has already divorced her husband.