Executive functions Executive functions are cognitive processes that control other brain activities and are predominantly functioning in the prefrontal areas of the frontal lobe. Executive functions are limited in capacity and accountable for the initiation, consolidation, regulation, and inhibition of cognitive, language, motor and emotional processes. Measuring executive functions is often less accurate than measuring non-executive tasks because of the interconnectedness and multi-determined complexity of the brain. Executive functions are hard to measure independently of all other cognitive functions and are often influenced by non-executive factors. The model uses thought and action schemas which are a series of learned thought and action sequences, like scripts, that specify behaviours during situations. Schemas are activated from perceptual stimuli or from the output of recently activated schemata. For an example, entering your kitchen to find a pile of unclean dishes (input) could initiate a behavioural response to clean (schema). and that they range in hierarchy. For instance, high-level schemas represent problem solving while low-level schemas typify actions. In the Norman-Shallice model, two main processes manage the functioning and control of schemas. Contention scheduling is a lower-level mechanism that regulates schemata processes for familiar, automatic actions as well as some novel situations. Schemas have selection conditions and are initiated if the level of activation reaches threshold. Connected schemata mutually inhibit one another. A schema encountering an increased number of activations will result in easier future access and greater suppression of the activation of those schema connected to it. Several concurrently run schemata, for instance walking and talking, are strengthened by use and take less attentional control. The SAS enables independent behaviour involved in memory, planning, decision making, cognitive estimation, problem solving, dangerous environments, novel situations, error inhibition, error correction, and initiating actions. Another error in the supervisory attentional system can lead to more devastating implications. When humans are faced with a threatening situation there is often limited time to generate the
fight-or-flight response ideally suited to increase survival. Cognitive paralysis is when an individual fails to respond or 'freezes' during an emergency because of either a temporal or cognitive deficiency. The inhibition of the SAS is the proposed temporal constraint during an emergency. If an appropriate pre-learned schema is retrievable, then a survival response will be initiated. However, if no existing schemata can respond, the result is cognitive paralysis, otherwise exhibiting irrational behaviour. Based on this understanding, one may wrongly speculate that the SAS is unfavourable in dangerous situations. The supervisory attentional system provides individuals with the ability to predict and prepare for situations mentally prior to any possible encounter. Many have argued about the specific roles of the SAS in survival situations; a general understanding is that it functions to increase the chance of survival and that it operates in conjunction with an integrated system. Throughout the 1980s and 1990s, much
neuropsychological research was conducted on the frontal lobes and prefrontal cortex (PFC). Over time, the supervisory attentional system was incorporated into research on age, brain injuries, psychological disorders,
degenerative diseases, substance abuse and more. The following section is a brief review on research involving the SAS. ==Research on supervisory attentional system==