Transcriptomics (RNA-seq/microarray) data normalization - FAQ

Hello! Being new to the site and while using the Allen Human Brain Atlas or more specifically the Differential Search of the Human Microarrays section (performing a search between two different brain areas ), I noticed that there is one singular fold change value, which appears near the heat map for every single gene and I was wondering how this specific fold change value has been estimated, especially in reference with the various expression values that are generated for the same search (and gene) once we decide to download the data in a .csv format. The same thing happens with the p-value as well. When it comes to the expression values of the .csv files on the other hand, what do they stand for and how are they connected to the heat map or the expression z-score and log2 intensity localized in the gene info section of the map in question? Looking forward to your response.