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Unconscious Learning. Conditioning to Subliminal Visual Stimuli

Published online by Cambridge University Press:  10 April 2014

Juan P. Núñez  and
Francisco de Vicente
Juan P. Núñez*
Affiliation:
University Pontificia Comillas of Madrid
Francisco de Vicente*
Affiliation:
University Complutense of Madrid
*
Correspondence concerning this article should be addressed to either Juan P. Núñez, Departamento de Psicología, Facultad de Ciencias Sociales y Humanas, Universidad Pontificia de Comillas de Madrid, C/ Universidad de Comillas n° 3, 28049, Madrid (Spain), or to Francisco de Vicente, Departamento de Psicología Básica I, Facultad de Psicología, Universidad Complutense de Madrid, Campus de Somosaguas, 28223, Madrid (Spain). E-mail: jnunez@chs.upco.esor, fvicente@sis.ucm.es
Correspondence concerning this article should be addressed to either Juan P. Núñez, Departamento de Psicología, Facultad de Ciencias Sociales y Humanas, Universidad Pontificia de Comillas de Madrid, C/ Universidad de Comillas n° 3, 28049, Madrid (Spain), or to Francisco de Vicente, Departamento de Psicología Básica I, Facultad de Psicología, Universidad Complutense de Madrid, Campus de Somosaguas, 28223, Madrid (Spain). E-mail: jnunez@chs.upco.esor, fvicente@sis.ucm.es
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Abstract

The role of consciousness in Pavlovian conditioning was examined in two experiments in which visually masked neutral words were used as the conditioned stimuli (CS) and an electric shock as the unconditioned stimulus (US). The inter-stimulus interval (ISI) was established individually. A detection threshold was used in Experiment 1 and an identification threshold in Experiment 2. The primary dependent variable was the skin conductance response (SCR). Results showed that the conditioned response (CR) was acquired by 58% of participants who perceived stimuli above the identification threshold, 50% of participants who perceived stimuli below the detection threshold, and 11% of participants who perceived stimuli below the identification threshold, but above the detection threshold. These results suggest that consciousness of the CS-US contingency is not a necessary condition for acquiring a CR of the autonomous nervous system (ANS).

Se analizó el papel de la consciencia en el condicionamiento pavloviano mediante dos experimentos en los que se utilizaron, como estímulos condicionados (ECs), palabras neutras visualmente enmascaradas y, como estímulo incondicionado (EI), un shock eléctrico. El intervalo inter-estímulo se estableció individualmente. Se utilizó un umbral de detección en el Experimento 1 y un umbral de identificación en el Experimento 2. La principal variable dependiente fue la respuesta de conductancia de la piel. Los resultados mostraron que la respuesta condicionada (RC) fue adquirida por el 58% de los sujetos que percibieron los estímulos por encima del umbral de identificación, por el 50% de los sujetos que percibieron los estímulos por debajo del umbral de detección y por el 11% de los sujetos que percibieron los estímulos por debajo del umbral de identificación, pero por encima del umbral de detección. Estos resultados sugieren que la conciencia de la contingencia EC-EI no es condición necesaria para adquirir una RC del sistema nervioso autónomo.

Keywords

Pavlovian conditioningbackward maskingsubliminal perceptionconscious andunconscious learningcondicionamiento pavlovianoenmascaramiento hacia atráspercepción subliminalaprendizaje consciente e inconsciente
Type
Articles
Information
The Spanish Journal of Psychology , Volume 7 , Issue 1 , May 2004 , pp. 13 - 28
Copyright
Copyright © Cambridge University Press 2004

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