1. Esteves, F., Dimberg, U. & Öhman, A. Automatically elicited fear: conditioned skin conductance responses to masked facial expressions. Cogn. Emotion 9, 99–108 (1994).
2. Ohman, A. & Soares, J. J. F. “Unconscious anxiety”: phobic responses to masked stimuli. J. Abnorm. Psychol. 103, 231–240 (1994).
3. Weiskrantz, L. Behavioural changes associated with ablation of the amygdaloid complex in monkeys. J. Comp. Physiol. Psychol. 49, 381–391 (1956).
4. Kapp, B. S., Pascoe, J. P. & Bixler, M. A. in Neuropyschology of Memory(eds Butters, N. & Squire, L. R.) 473–488 (Guilford, New York, 1984).
5. Davis, M. in The Amygdala: Neurobiological Aspects of Emotion, Memory and Mental Dysfunction(ed. Aggleton, J. P.) 255–306 (Wiley-Liss, New York, 1992).