The salience (also called saliency) of an item is its state or quality of standing out relative to other items. The concept of salience appears in several domains, as described below.
Neuroscience
In Neuroscience, saliency detection is considered to be a key attentional mechanism that aids learning and survival by enabling organisms to focus their limited neurocomputational resources on a small yet pertinent subset of the available sensory data. Saliency can arise either in the spatial domain, such as a red dot surrounded by white dots, or in the temporal domain, as exemplified by the flickering message indicator of an answering machine, or in both domains simultaneously, such as a red dot moving relative to a white background. While the examples above focus on visual saliency, similar mechanisms operate in other sensory modalities - sounds, flavors, scents, etc., can all stand out and attract attention. Generally speaking, saliency detection leads to bottom-up influences that trigger reactive attentional selections. Humans and other animals continuously integrate these bottom-up influences with top-down influences that guide attention proactively, such as when looking ahead of moving objects.
Semiotics
In Semiotics, salience is considered in the context of how the individual's internal mental organisation is configured to eliminate “ cognitive clutter”, and leaves only the salient signs. The process of converting signs into meaning is called semiosis. This is a metacognitive process working through schema that constitute a model of the world. Such schema are created through, and monitored using, a range of skills including pattern matching, analysis, and synthesis.
Meaning can be described as the “…system of mental representations of an object or phenomenon, its properties and associations with other objects and/or phenomena. In the consciousness of an individual, meaning is reflected in the form of sensory information, images and concepts.” (Bedny & Karwowsky, 2004). It is either denotative or connotative but the sign system for transmitting meanings can be uncertain in its operation or conditions may disrupt the communication and prevent accurate meanings from being decoded.
Further, meaning is socially constructed and dynamic as the culture evolves. This is problematic because an individual’s frame of reference and experience may produce some divergence from some of the prevailing social norms. So the salience of data will be determined by both situational and emotional elements in a combination relatively unique to each individual. For example, a person with an interest in botany may allocate greater salience to visual data involving plants, whereas a person training as an architect may scan buildings to identify features of interest. A person's world view or Weltanschauung may predispose salience to data matching those views. Because people live for many years, responses become conventional. At a group or community level, the conventional levels of significance or salience are slowly embedded in the sign systems and culture, and they cannot arbitrarily be changed.
Other Meanings
In Clips the salience rule property allows the user to assign a priority to a rule.
External links
References
Bedny, G. & Karwowski, W. (2004) Meaning and sense in activity theory and their role in the study of human performance. International Journal of Ergonomics and Human Factors. (26:2, 121-140.)