ABSTRACT
The term executive function has been spoken of very often in a unitary fashion, but in fact, it is an umbrella term, as is cognitive control, for a group of mental processes, not all of which are so “higher order” in the rather exalted manner in which they are often regarded. It would be preferable to use the plural form, “executive functions” or “cognitive control processes.” I also recommend reserving the term “metacognition” not as a synonym for the entire domain of executive functions but rather for the very final step in development of the domain. Inhibition, something that is also a component of the domain of motor control, is a very basic aspect of early development of executive function. Working memory, as can be demonstrated nonverbally in laboratory animal experiments, is the next relatively early basic component of executive functions. In human beings, there is a developmental trajectory in which inhibition “checks in” at a simple level towards the end of the year of life, while working memory also enters the picture very gradually, perhaps not so apparent until there is enough inhibition that it is possible to see at preschool age. Gradually there are milestones marking blossoming of what are commonly called “higher order” mental processes (organization and planning) that exert control over an individual’s actions and emotional expressions in a manner we refer to as goal-oriented. The executive functions we subsume under “behavior regulation” include inhibition and shifting, as well as a very special case of inhibition, emotional control over overt expressions such as immediate “emoting” (crying, yelling, aggressive words or actions). The cognitive controls include initiating (getting started), sustaining, and shifting (which can be thought of as a two-step sequence 44of inhibiting an ongoing activity in order to initiate another one). This is my analogy to the automobile “gear shift”; the processes implied in paying attention, what is referred to often as executive attention (Initiate, Sustain, Inhibit, and Shift). The components that “check in” later are higher order functioning; these are planning (across the time dimension, especially as regards time management), organization (which includes spaces and objects, organization of materials and pieces of work physically embodied), and still later, self-monitoring or checking back over that which has been planned and organized in order to see whether a goal has been met. Very late in the developmental trajectory, possibly as late as college age, there arises true “metacognition” in the executive domain, which means that a person has self-knowledge of his or her cognitive strengths and weaknesses. Metacognition involves a complex ability to plan and organize towards a goal with self-knowledge of strengths and how strategies can be utilized to circumvent or compensate for weaknesses of the person’s non-executive cognitive endowments, such as language, visuospatial, or motor abilities.
