Validation Of Cross-modality Fear Generalization: Influence Of Cross-modality Direction And Anxiety Level On Generalization Effect

Fear generalization is an important mechanism for individuals to avoid potential threats,which has positive evolutionary significance.However,excessive fear generalization will cause physical and mental disturbance,which is an important feature of various anxiety disorders.Based on the fear network theory and previous studies on fear generalization based on perception and semantics,it can be inferred that if stimuli presented in two sensory modalities are linked with the same semantics,then fear learned from one sensory modality may be generalized to the other sensory modality.Gerdes et al.used electrical stimulation as a means of fear induction in the normal population and confirmed for the first time the phenomenon of cross-modality fear generalization from visual modality to auditory modality,which was specifically manifested as the self-reported fear emotion showed cross-modality generalization but the skin electrophysiological response was not significantly generalized.Can cross-modality fear generalization be tested using different fear stimuli? Are the physiological indexes represented by skin potential also generalized? Does the generalization of auditory to visual modality hold? Is cross-modality fear generalization more severe in clinical populations such as anxiety disorders? Since the fear generalization cross-modality phenomenon is rarely studied in humans,it needs further investigation.This study included two experiments.In experiment 1,56 normal adults were selected as subjects.White noise was used as the fear stimulus and experimental materials were innovatively selected to verify the cross-modality fear generalization from the visual to auditory modality and from the auditory to visual modality respectively,and the differences in the generalization effects were compared.In experiment 2,28 normal control adults and 28 people with high anxiety symptoms were used as subjects.Experiment 1 paradigm was adopted to test the difference in cross-modality fear generalization between the general population and the high anxiety population.In both experiments,unconditional stimulation expectation,subjective fear degree and skin electrophysiological response were used as measurement indicators.The results of study 1 showed that:(1)Fear learned from one sensory modality can be generalized to another sensory modality,and the results of behavioral and physiological indicators supported the realization of cross-modality fear generalization.(2)In terms of behavioral indicators,fear generalization could be achieved in both directions from visual to auditory and from auditory to visual.However,in terms of physiological indicators,only the subjects in the visual to auditory group showed fear generalization,and the subjects in the auditory to visual group also learned fear,but the result was not significant in the generalization stage.Therefore,the fear generalization effect from visual modality to auditory modality was better.The results of study 2 showed that:(1)Fear generalization from visual modality to auditory modality was also observed in anxious people,and the results were supported by physiological and behavioral indicators.(2)In terms of subjective fear degree,the anxious people had more significant cross-modality fear generalization effect than the general population,but skin conductance responses data did not support this result.In this study,pictures and sounds of animals were selected as stimulus materials,and a novel cross-modality fear generalization paradigm was proposed;Cross-modality fear generalization was observed for the first time on skin conductance responses data;The fear generalization from auditory modality to visual modality was verified for the first time;Cross-modality fear generalization was first demonstrated in an anxious population.Further research on cross-modality fear generalization has enriched and expanded this new research field,emphasized the importance of multi-sensory research,which is more in line with the acquisition of fear in real situations,has better ecological validity,and contributes to the study of the underlying processes of psychological mechanisms.As a mechanism for the acquisition and extinction of pathological fear,cross-modality fear generalization has important implications for the diagnosis and treatment of various anxiety disorders in clinic.