[Effect of associative strength of schema elements on intensity of startle reaction]

This study examined the effects of the strength of the connection between elements of an event schema on the surprise reaction elicited by a schema-discrepant event sequence. The strength of the connection between schema elements was manipulated by the probability of an event in an event sequence given that a certain sequence had preceded that event. Strong connections between schema elements were expected to result from repeated exposure to an invariant event sequence. Weak connections were expected to result from repeated exposure to a variable event sequence. The results showed that an unexpected deviation from a strong connection led to a longer reaction time delay to a probe stimulus as compared to a deviation from a weak connection. This finding is consistent with the assumption that the modification of a strong connection is more effortful than the modification of a weak connection. Furthermore, there was a tendency towards higher surprise ratings when the unexpected event deviated from a strong connection, indicating that the discrepancy is more severe. A second experiment showed that the schema had changed in response to the first presentation of the schema-discrepant event: A second presentation of the schema-discrepant event was rated as less surprising and led to a shorter reaction time delay as compared to the first presentation. Furthermore, the results indicated that the specific circumstances of the first presentation are taken into account when the schema is changed.