A superstimulus or superreleaser is an exaggerated version of a stimulus to which there is an existing response tendency, or any stimulus that elicits a response more strongly than the stimulus that normally releases it.
The concept is derived from ethology. Konrad Lorenz observed that birds would select for brooding eggs that resembled those of their own species but were larger. Niko Tinbergen, following his extensive analysis of the stimulus features that elicited food-begging in the chick of the Herring Gull, constructed an artificial superstimulus consisting of a red knitting needle with three white bands painted round it; this elicited a stronger response than an accurate three-dimensional model of the parent's head (white) and bill (yellow with a red spot).
Lorenz and Tinbergen accounted for the superreleaser effect in terms of the concept of the innate releasing mechanism; however this concept is no longer widely used. The core observation that simple features of stimuli may be sufficient to trigger a complex response remains valid, however.
It is sometimes argued that phenomena such as sexual fetishes and the taste for junk food can be partially explained as examples of superstimulation. Modern artefacts may activate instinctive responses which evolved in a world without shiny fabrics or double cheeseburgers, where shiny skin was a sign of health in a prospective mate, and fat was a vital nutrient.
