Journal of Psychopathology and Behavioral Assessment, Vol. 20, No. 4, 1998 Stability of Cognitive Bias for Threat Cues in Phobia Merel Kindt 1,3 and Jos F. Brosschot 2 Accepted: September 22, 1998 The present study examined whether the cognitive bias for threat is a stable phenomenon in spider phobics and not in nonphobic controls. The rationale of this study was that the use of emotional bias for individual assessment in clinical practice requires stability of this phenomenon. In order to assess the stability of the emotional bias, the spider Stroop task was administered twice to spider phobics and controls, with a time lag of 3 weeks. In two experiments, spider phobics (n exp . 1 = 20; n exp .2 = 33) and controls (n exp . 1 = 24; n exp . 2 = 25) were selected on basis of a structured interview. In the second experiment, subjects anticipated exposure to a real-life spider. Emotional bias was inferred from color-naming latencies on spider words versus control words. In line with our prediction, the bias for threat was stable in spider phobic individuals but not in controls. This stability could not be attributed to a general cognitive characteristic because a standard Stroop task did not differentiate between the spider phobics and the controls. The results support the view that cognitive processing of threat in anxiety is stable. It is proposed to use both the emotional bias and its stability as measures of the constraints on the flexibility of the cognitive fear-network. KEY WORDS: cognitive bias; spider phobia; test-retest reliability. 1 Department of Medical, Clinical and Experimental Psychology, Maastricht University, Maastricht, The Netherlands. 2 Section of Clinical and Health Psychology, University of Leiden, Leiden, The Netherlands. 3 To whom correspondence should be addressed at Maastricht University, Faculties of Medicine and Health Sciences, Department of Medical, Clinical and Experimental Psychology, P.O. Box 616, 6200 MD Maastricht, The Netherlands. 351 0882-2689/98/1200-0351$13.00/0 C 1998 Plenum Publishing Corporation