Executive functions

Higher animals, including humans use their brain to control their behavior. The cognitive processes  they use are known as  executive functions (also called cognitive control): They are used to choose what to do and what to control, and whether the chosen goals have been achieved.  Some executive functions are basic cognitive processes such as attentional control, cognitive inhibition, inhibitory control, working memory and cognitive flexibility. Higher-order executive functions require the use of several basic executive functions and include planning and fluid intelligence (for example reasoning and problem-solving).

Executive functions develop over time. They change during lifespan of an individual and can be improved at any time. Similarly, these cognitive processes can be adversely affected by different events.

Tests have been developed to assess the level of these functions. Rating scales can be used.  These tests are usually performed as a part of a larger series of tests, which ain to find neurological and psychiatric disorders.  An example of such a test is the Stroop test. An example of a scale is call Behaviour Rating Inventory of Executive functions.

A counterexample of this is operant and classical conditioning: With these processes, individuals are "taught" to react in a certain way to a given stimulus.  In such a situation, the individual must override the response to a stimulus using executive functions. This is called inhibitory control. The prefrontal cortex is necessary but not solely sufficient for executive functions; other parts of the brain also have a role in mediating inhibitory control.

Certain conditions affect cognitive control. These include addiction, attention deficit hyperactivity disorder, Core EFs are inhibition [response inhibition (self-control—resisting temptations and resisting acting impulsively) and interference control (selective attention and cognitive inhibition)], working memory, and cognitive flexibility (including creatively thinking "outside the box," seeing anything from different perspectives, and quickly and flexibly adapting to changed circumstances). ... EFs and prefrontal cortex are the first to suffer, and suffer disproportionately, if something is not right in your life. They suffer first, and most, if you are stressed (Arnsten 1998, Liston et al. 2009, Oaten & Cheng 2005), sad (Hirt et al. 2008, von Hecker & Meiser 2005), lonely (Baumeister et al. 2002, Cacioppo & Patrick 2008, Campbell et al. 2006, Tun et al. 2012), sleep deprived (Barnes et al. 2012, Huang et al. 2007), or not physically fit (Best 2010, Chaddock et al. 2011, Hillman et al. 2008). Any of these can cause you to appear to have a disorder of EFs, such as ADHD, when you do not. You can see the deleterious effects of stress, sadness, loneliness, and lack of physical health or fitness at the physiological and neuroanatomical level in the prefrontal cortex and at the behavioral level in worse EFs (poorer reasoning and problem-solving, forgetting things, and impaired ability to exercise discipline and self-control). ...EFs can be improved (Diamond & Lee 2011, Klingberg 2010). ... At any age across the life cycle EFs can be improved, including in the elderly and in infants. There has been much work with excellent results on improving EFs in the elderly by improving physical fitness (Erickson & Kramer 2009, Voss et al. 2011) ... Inhibitory control (one of the core EFs) involves being able to control one's attention, behavior, thoughts, and/or emotions to override a strong internal predisposition or external lure, and instead do what's more appropriate or needed. Without inhibitory control we would be at the mercy of impulses, old habits of thought or action (conditioned responses), and/or stimuli in the environment that pull us this way or that. Thus, inhibitory control makes it possible for us to change and for us to choose how we react and how we behave rather than being unthinking creatures of habit. It doesn't make it easy. Indeed, we usually are creatures of habit and our behavior is under the control of environmental stimuli far more than we usually realize, but having the ability to exercise inhibitory control creates the possibility of change and choice. ... The subthalamic nucleus appears to play a critical role in preventing such impulsive or premature responding (Frank 2006).Figure 4: Executive functions and related terms autism, and other central nervous system disorders. Stimulus-driven behavioral responses that are associated with a particular rewarding stimulus tend to dominate one's behavior in an addiction.

 Hypothesized role 
The executive system is thought to be heavily involved in handling new situations outside the domain of some of our 'automatic' psychological processes that could be explained by the reproduction of learned schemas or set behaviors. Psychologists Don Norman and Tim Shallice have outlined five types of situations in which routine activation of behavior would not be sufficient for optimal performance:

 Those that involve planning or decision-making
 Those that involve error correction or troubleshooting
 Situations where responses are not well-rehearsed or contain new sequences of actions
 Dangerous or technically difficult situations
 Situations that require the overcoming of a strong habitual response or resisting temptation.

A prepotent response is a response for which immediate reinforcement (positive or negative) is available or has been previously associated with that response. 

Executive functions are often invoked when it is necessary to override prepotent responses that might otherwise be automatically triggered by stimuli in the environment. For example, on being presented with a potentially rewarding stimulus, such as a tasty piece of chocolate cake, a person might have the automatic response to take a bite. However, where such behavior conflicts with internal plans (such as having decided not to eat chocolate cake while on a diet), the executive functions might be engaged to inhibit that response.

Although suppression of these prepotent responses is usually considered adaptive, problems for the development of the individual and the culture arise when feelings of right and wrong are overridden by cultural expectations or when creative impulses are overridden by executive inhibitions. 

 References 

 Other websites 



 The National Center for Learning Disabilities

Category:Cognition
Category:Addiction