Biomaterial Database

Emotional conditioning to masked stimuli: expectancies for aversive outcomes following nonrecognized fear-relevant stimuli. 1998

A Ohman, and J J Soares

Department of Clinical Neuroscience, Karolinska Insitute and Hospital, Stockholm, Sweden. arneo@psyk.ks.se

The role of conscious awareness in human Pavlovian conditioning was examined in 2 experiments using masked fear-relevant (snakes and spiders; Experiments 1 and 2) and fear-irrelevant (flowers and mushrooms; Experiment 1) pictures as conditioned stimuli, a mild electric shock as the unconditioned stimulus, and skin conductance responses as the primary dependent variable. The conditioned stimuli were presented briefly (30 ms) and were effectively masked by an immediately following masking stimulus. Experiment 1 demonstrated nonconscious conditioning to fear-relevant but not to fear-irrelevant stimuli. Even though the participants could not recognize the stimuli in Experiment 2, they differentiated between masked stimuli predicting and not predicting shocks in expectancy ratings. However, expectancy ratings were not related to the conditioned autonomic response.

UI	MeSH Term	Description	Entries
D008297	Male		Males
D010470	Perceptual Masking	The interference of one perceptual stimulus with another causing a decrease or lessening in perceptual effectiveness.	Masking, Perceptual,Maskings, Perceptual,Perceptual Maskings
D003213	Conditioning, Psychological	Simple form of learning involving the formation, strengthening, or weakening of an association between a stimulus and a response.	Conditioning, Psychology,Psychological Conditioning,Social Learning Theory,Social Learning Theories,Theory, Social Learning
D005108	Extinction, Psychological	The procedure of presenting the conditioned stimulus without REINFORCEMENT to an organism previously conditioned. It refers also to the diminution of a conditioned response resulting from this procedure.	Psychological Extinction,Extinction (Psychology),Extinctions (Psychology),Extinctions, Psychological,Psychological Extinctions
D005239	Fear	The affective response to an actual current external danger which subsides with the elimination of the threatening condition.	Threat Cues,Threat Sensitivity,Cue, Threat,Fears,Sensitivity, Threat,Threat Cue,Threat Sensitivities
D005260	Female		Females
D006185	Habituation, Psychophysiologic	The disappearance of responsiveness to a repeated stimulation. It does not include drug habituation.	Habituation (Psychophysiology),Habituation, Psychophysiological,Psychophysiologic Habituation,Psychophysiological Habituation,Habituations (Psychophysiology)
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D000328	Adult	A person having attained full growth or maturity. Adults are of 19 through 44 years of age. For a person between 19 and 24 years of age, YOUNG ADULT is available.	Adults
D000339	Affect	The feeling-tone accompaniment of an idea or mental representation. It is the most direct psychic derivative of instinct and the psychic representative of the various bodily changes by means of which instincts manifest themselves.	Mood,Affects,Moods