nondeclarative

Nondeclarative refers to forms of knowledge, memory, or processing that are not available to conscious introspection or not described by explicit statements. In psychology and cognitive science, the term is most often applied to nondeclarative (implicit) memory, a class of long-term memory that underlies skills, habits and conditioned responses and cannot be readily verbalized. This contrasts with declarative (explicit) memory, which encodes facts and events that can be consciously recalled.

Core components of nondeclarative memory include procedural memory (skills and actions such as riding a bicycle or playing a musical instrument), priming (changes in perception or belief due to prior exposure), and various forms of conditioning (classical and operant). These memories typically operate without conscious awareness and are learned through repetition and experience.

Neuroanatomically, nondeclarative memory relies on different brain systems than declarative memory. Procedural memory involves the basal ganglia and cerebellum, while priming and other nondeclarative processes recruit extrastriate and prefrontal cortical networks. The hippocampus and related medial temporal structures are especially important for declarative memory, and individuals with hippocampal damage often retain intact nondeclarative memory despite impairments in explicit recall.

In computing and information systems, nondeclarative is sometimes used informally to describe approaches that do not specify results declaratively, commonly referring to imperative or procedural programming styles that describe how to perform tasks rather than what outcomes should be achieved. The widely used contrast remains declarative programming, where the emphasis is on describing the desired results or constraints.

See also: declarative memory, implicit memory, procedural memory, priming, conditioning, imperative programming, declarative programming.