flankertest

Flankertest, commonly referred to as the flanker task, is a cognitive psychology paradigm used to study selective attention and response inhibition. In its standard form, participants view a row of five stimuli consisting of a central target and flanking distractors. They must identify or respond to the center stimulus while ignoring the flankers. Flankers can be congruent, meaning they require the same response as the target, or incongruent, meaning they require a different response. Some variants include neutral flankers that do not map to a response.

The task has several common implementations. In the arrow version, five arrows are presented and the participant reports the direction of the central arrow. In the letter version, letters are used as stimuli; in any case reaction time and accuracy are recorded. The key finding is the flanker effect: responses are typically slower and sometimes less accurate on incongruent trials than on congruent trials.

Flankertest was introduced by Eriksen and Eriksen in 1974 and has since become a standard tool for examining automatic processing versus controlled processing, as well as spatial and stimulus-driven attention. It is widely used in basic cognitive research as well as in clinical studies of aging, ADHD, schizophrenia, and brain injury. Additional uses include neuroimaging studies that seek to map the neural correlates of selective attention, and the measurement of components such as event-related potentials.

Limitations include that the size of the interference effect depends on stimulus similarity, response mappings, and task parameters, complicating cross-study comparisons. See also the Stroop task and the broader literature on selective attention.