Departing from the neuroimaging studies it is evident that BA46, as well as BA9/10, is involved in memory, particularly working memory and memory control and organization. Because of the association of working memory with prefrontal activity, some clarification about working memory is important. It has been assumed that working memory is involved in a diversity of cognitive processes, including language comprehension, planning, reasoning, problem solving and even consciousness. It is important to emphasize that span tests (e.g., digit span) (working memory storage process) exhibit greater dependence on the posterior cortex, whereas delayed recognition performance (working memory rehearsal process) exhibits greater dependence on the prefrontal cortex. When information has to be manipulated, increased prefrontal activity is found. The manipulation-related processes ascribed to the dorsolateral prefrontal cortex are fundamentally extramnemonic in nature (that means, metamemory). Whereas they play a fundamental role in the exercise of executive control of working memory, they do not govern the storage per se of the information held in working memory. The participation of the left anterior middle frontal gyrus in language is also shared by other left prefrontal convexital areas; according to current knowledge of languages disturbances associated with brain pathology, other linguistic functions potentially related with BA46, such as verbal initiative and language pragmatics, have not been fully approached in fMRI studies. Two fMRI studies attract special attention: (1) “Willed acts” in the two response modalities studied (speaking a word, or lifting a finger) were associated with increased blood flow in BA46; (2) mirror neurons: a basic circuit underlying imitation learning including the inferior parietal lobule and the posterior part of the inferior frontal gyrus plus the adjacent premotor cortex (mirror neuron circuit) has been proposed. During pause, the middle frontal gyrus (area 46) plus those structures involved in motor preparation (dorsal premotor cortex, superior parietal lobule, rostral mesial areas) also become active.
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