ISSN : 1226-9654
Fear is a primary emotion. It serves the essential function that allows organisms to detect danger signals and react accordingly in the environment. Through evolution, most species in the animal kingdom including humans have developed an efficient learning system to predict potentially threatening stimuli or situation. A simple associative form of learning, called Pavlovian or classical conditioning has been the most popular paradigm to describe the process by which neutral stimulus gains a biological significance. Because Pavlovian fear conditioning is simple and fast, numerous research papers have employed this procedure to elucidate the brain mechanisms of fear learning. Here we review the history of modern fear conditioning studies and the latest development in understanding anatomical, physiological and molecular mechanisms of fear memory formation. In addition, we summarize findings on fear extinction, an experimental process by which learned fear response is suppressed. We hope to validate an argument that fear conditioning is a useful tool in answering the fundamental question in neuroscience, the molecular basis of learning and memory.
Two studies were conducted to investigate the affective, motivational and physiological correlates of empathy. In study 1, participants completed PANAS, BAS/BIS and empathy scales. the data were summarized through both correlational analysis and path analysis method. BAS was significantly associated with empathy, but both NA and BIS were equally related to alexithymia. The capacity for empathy was inversely related alexithymia. In study 2, the effects of empathy, emotional stimuli and sex on heart rate variability(HRV) were examined. participants were assigned to either high empathy group or low empathy group based on empathy test score. During baseline and viewing the video clips, HRV was recorded by means of electrocardiograph. Participants who had higher empathy reported more relevant subjective feeling and exhibited more significant reduction of respiratory sinus arrhythmia(RSA) level during viewing emotional video clips than those who had lower empathy. Heart rate and low-frequency power spectral density(LF PSD) were unrelated to empathy. Women showed higher reduction of RSA level to the emotional video clips than men. These findings suggests that empathy is associated with global positive personality traits and high level of empathy is related with high degree of RSA reactivity to emotional stimuli. Implications for the study of affective and motivational style and RSA in empathy were discussed.
Three experiments were conducted to explore the interactive effect of antecedent's gender marker and mention order on pronoun referential resolution. In Experiment 1, using proper name for antecedents, Participants were read the sentences by RSVP and naming to antecedent words. The results showed that any variable did not sensitive to naming time. In Experiment 2, Participants were read the sentences by RSVP and name to antecedent words. The results showed that the effect of mention order was found. The first mentioned antecedent faster than the second mentioned condition for naming time. In Experiment 3, using proper name for antecedents, Participants were read the sentences by self-paced and probe recognition to antecedent words in unambiguous gender cue and subject-subject condition. The results showed that main effects of antecedent's gender marker in self-paced reading time. The female marker condition slower than the male condition. using role name for antecedents, These results were discussed from a point of view of dynamically interactive models for pronoun resolution.
Psychophysical numbing refers a phenomenon in which the perceived value of saving a fixed number of lives decreases as the total number of lives at risk (“reference group size”) increases. The first experiment replicated factors affecting psychophysical numbing in a different experimental procedure than previous researches. The results showed that psychophysical numbing responding increased, when decision makers evaluated the options in the economic-focus. The second experiment examined the psychophysical numbing in two different presentation mode, namely separate versus joint presentation. In contrast to affect heuristic and evaluability hypothesis, psychophysical numbing increased in joint presentation, in which two options could be compared and analysed. The problems of present theories explaining psychophysical numbing and alternative theories were discussed.