Dot-probe paradigm

The dot-probe paradigm is a test used by cognitive psychologists in order to assess selective attention. Initially developed by Halkiopoulos (1981), this method examined attentional biases to threatening auditory information, when threatening and non-threatening information was presented simultaneously to both ears in a dichotic listening task. This method was then adapted to the visual modality (also known as the visual-probe task) 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 stimulus 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). This method of retraining the attentional bias is called attentional retraining.

Some studies that use a dot-probe task

 * Halkiopoulos, C. (1981). Towards a psychodynamic cognitive psychology. Unpublished manuscript, University College London, London, UK.
 * MacLeod, C., Mathews, A. M., & Tata, P. (1986). Attentional bias in emotional disorders. Journal of Abnormal Psychology, 95, 15-20.
 * Amin, Z., Constable, R.T., Canli, T. (2004). Attentional bias for valenced stimuli as a function of personality in the dot-probe task. Journal of Research in Personality, 38, 15-23.
 * Bradley, B.P. (1998). Attentional Bias for Threatening Facial Expressions in Anxiety: Manipulation of Stimulus Duration.
 * Mogg, K, & Bradley, B.P. (1999) Orienting of attention to threatening facial expressions presented under conditions of restricted awareness. Cognition and Emotion, 13, 713-740.
 * Mather, M., & Carstensen, L. L. (2003). Aging and attentional biases for emotional faces. Psychological Science, 14, 409-415. PDF
 * Schoth, D. E., & Liossi, C. (2010). Attentional bias towards pictorial representations of pain in individuals with chronic headache. The Clinical Journal of Pain. 26 (3): 244 - 250.
 * Mathews, A., & MacLeod, C. (2002). Induced processing biases have causal effects on anxiety. Cognition & Emotion, 16(3), 331-354.