The dot-probe paradigm (also known as the visual-probe task) is a test used by cognitive psychologists in order to assess selective attention, originally developed by MacLeod, Mathews & Tata (1986). In many cases, the dot-probe paradigm is used to assess selective attention to threatening stimuli in individuals diagnosed with anxiety disorders. In addition, biases have been investigated in other disorders via this paradigm, including depression, post-traumatic stress disorder and chronic pain. Participants are situated in front of a computer screen and their chins are securely placed on a chin rest. Participants are asked to stare at a fixation cross on the center of the screen. Two stimuli, one of which is neutral and one of which is threatening, appear randomly on either side of the screen. The stimuli are presented for a predetermined length of time (most commonly 500ms), before a dot is presented in the location of one former stimulus. Participants are instructed to indicate the location of this dot as quickly as possible, either via keyboard or response box. Latency is measured automatically by the computer. The fixation cross appears again for several seconds and then the cycle is repeated. Quicker reaction time to the dot when it occurs in the previous location of a threatening stimuli is often interpreted as vigilance to threat.
Researchers have recently begun using a modified version of the dot-probe task to retrain the attentional bias. In this modified version of the task the probe replaces the neutral stimuli 100% of the time or the salient stimuli 100% of the time. Over the course of a number of trials the attentional bias for salient stimuli can be reduced (in the case of the 'replace-neutral' condition) or enhanced (in the case of the 'replace-salient' condition).[1] This method of retraining the attentional bias is called attentional retraining.