It is proposed that prefrontal lobe participates in two closely related but different executive functions abilities: (1) problem solving, planning, concept formation, strategy development and implementation, working memory, and the like (�metacognitive executive functions�); that is, executive functions as usually they are understood in contemporary neurosciences; and (2) coordinating cognition ... [Show full abstract] and emotion/motivation (�emotional executive functions�); that is, fulfilling biological needs according to some existing conditions. The first one depends on the dorsolateral prefrontal areas, whereas the second one is associated with orbitofrontal and medial frontal areas. Current executive functions tests basically tap the first ability (metacognitive). Solving everyday problems (functional application of executive functions), however, mostly requires the second ability (emotional); most contemporary executive functions tests consequently have limited ecological validity. Contrary to the traditional points of view, recent evidence points that human prefrontal lobe is similar to the other primates and hominids. Other primates and hominids probably possess the second (emotional executive functions) prefrontal ability, but not the first (metacognitive executive functions) one. It is argued that the first executive function (metacognitive) ability is the result of the development and evolution of some �conceptualization instruments�; language (and written language as an extension of oral language) may represent the most important one; metacognitive executive functions are significantly dependent of culture and cultural instruments. The second executive function ability (emotional) is the result of a biological evolution shared by other primates.