ABSTRACT
The orienting response (OR) concept has had substantive impact on physiological, psychological, and psychophysiological theory and research over the past eight decades. As a purported mechanism to enhance perception and action, the OR has broad potential significance for concepts of attention, learning, memory, motivation and emotion. In Pavlov’s original 1910 formulation, the orientation-investigatory reflex entailed both common and stimulus- or context-specific adjustments (see Pavlov, 1927). Subsequent theorists, however, generally focused on the common features of the OR, considering these to be distinct from associated “adaptation reflexes” that may include more context-specific adjustments (Anokhin, 1959; Sokolov, 1963). In contrast to the OR, Sokolov viewed the defensive response (DR) as a protective reaction against intense or potentially injurious stimuli, entailing a diminished sensory sensitivity and perceptual processing. Like the OR, the DR was believed to evidence many generalized features across evocative conditions, in spite of potentially varied somatic responses that may emerge in different behavioral contexts (Sokolov, 1963). In their traditional formulations, therefore, the OR and the DR represent two opposing core patterns of generalized adaptive adjustment, which would be expected to manifest in diverse behavioral contexts.
