Functional magnetic resonance imaging (fMRI) using the blood oxygenation level dependent (BOLD) response depicts the neuroanatomical correlates of cognitive processes and contributes to the understanding of memory functions. Working memory utilizes different neuroanatomical areas for temporarily storing and manipulating information content. Visual working memory is mainly considered to be an interaction of the prefrontal cortex which contributes to attention functions, temporal regions which store different object categories and posterior parietal and occipital regions which are sensitive to object number and complexity and possibly also store parts of objects. Expertise leads to the creation of long-term entries that support visual working memory entries. Well-known objects are represented with less neural effort in regions of the visual working memory network than unknown objects.