We think, we act.

One of the most intriguing relationships developed in the narrative of City of Glass is that between the characters' mental states and their interactions with their environments.
For example, Peter Stillman Jr. was locked in a dark room for a long period in his early life, meaning that he had little interaction with or understanding of physical spaces. This is reflected in his mental development - he has difficulty learning how to speak and requires a lifetime of therapy.
Peter Stillman Sr. has a history of unconventional practices, both in his scholarship and in the raising of his son. He is undoubtedly a smart man, but perhaps started losing sanity after the death of his wife. When he is freed from prison, he starts walking in the paths of the shapes of the letters to spell out the name of one of his obsessions. This behavior, coupled with the conversations that he has with Daniel Quinn (in which he goes on odd tangents and exhibits his poor memory), build an idea of his character in the reader's mind. Auster couples the character's mental state with his outward behavior to build a singular personality. It makes sense that a deranged one-time professor would use his walks through a certain block radius to spell out that which occupies his mind while collecting urban detritus in a bag along the way. The way he interacts with the physical environment around him is directly tied to the mental processes occurring inside his mind.
Finally, Daniel Quinn wants to be alone. Early in the book, when he goes on walks, places meld into one and he feels like he is nowhere. The way he processes the stimuli around him is tied to his thoughts and desires. He wants to be alone, so he ignores everything, and feels like he is walking in a void. Later, when Quinn starts living in the alleyway, his relationship to his environment changes. He becomes super focused on the Stillman apartment, and is consumed by his thoughts about the case. During this period, nothing else matters to him except the bare basics of sleeping and eating, which get reduced to a minimum. Everything in his mind is focused on the case, and his physical behavior towards the outside world reflects this.
The characters in the novels may illustrate extreme examples, but I believe that the characteristics of our mental processes definitely affect the way in which we act towards and are influenced by the places and spaces around us.