Negativity effect

The negativity bias, also known as the negativity effect, refers to the notion that, even when of equal intensity, things of a more negative nature (e.g. unpleasant thoughts, emotions, or social interactions; harmful/traumatic events) have a greater effect on one's psychological state and processes than do neutral or positive things. In other words, something very positive will generally have less of an impact on a person's behavior and cognition than something equally emotional but negative. The negativity bias has been investigated within many different domains, including the formation of impressions and general evaluations; attention, learning, and memory; and decision-making and risk considerations.

Paul Rozin and Edward Royzman proposed four elements of the negativity bias in order to explain its manifestation: negative potency, steeper negative gradients, negativity dominance, and negative differentiation.

Negative potency refers to the notion that, while possibly of equal magnitude or emotionality, negative and positive items/events/etc. are not equally salient. Rozin and Royzman note that this characteristic of the negativity bias is only empirically demonstrable in situations with inherent measurability, such as comparing how positively or negatively a change in temperature is interpreted.

With respect to positive and negative gradients, it appears to be the case that negative events are thought to be perceived as increasingly more negative than positive events are increasingly positive the closer one gets (spatially or temporally) to the affective event itself. In other words, there is a steeper negative gradient than positive gradient. For example, the negative experience of an impending dental surgery is perceived as increasingly more negative the closer one gets to the date of surgery than the positive experience of an impending party is perceived as increasingly more positive the closer one gets to the date of celebration (assuming for the sake of this example that these events are equally positive and negative). Rozin and Royzman argue that this characteristic is distinct from that of negative potency because there appears to be evidence of steeper negative slopes relative to positive slopes even when potency itself is low.

Negativity dominance describes the tendency for the combination of positive and negative items/events/etc. to skew towards an overall more negative interpretation than would be suggested by the summation of the individual positive and negative components. Phrasing in more Gestalt-friendly terms, the whole is more negative than the sum of its parts.

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