In two experiments, the time course of the expression of fear in trace (hippocampus-dependent) versus delay (hippocampus-independent) conditioning was characterized with a high degree of temporal specificity using fear-potentiated startle. In experiment 1, groups of rats were given delay fear conditioning or trace fear conditioning with a 3- or 12-sec trace interval between conditioned stimulus (CS) offset and unconditioned stimulus (US) onset. During test, the delay group showed fear-potentiated startle in the presence of the CS but not after its offset, whereas the trace groups showed fear-potentiated startle both during the CS and after its offset. Experiment 2 compared the time course of fear expression after trace conditioning with the time course in two delay conditioning groups: one matched to the trace conditioning group with respect to CS duration, and the other with respect to ISI. In all groups, fear was expressed until the scheduled occurrence of the US and returned to baseline rapidly thereafter. Thus, in both trace and delay fear conditioning, ISI is a critical determinant of the time course of fear expression. These results are informative as to the possible role of neural structures, such as the hippocampus, in memory processes related to temporal information.
Download full-text PDF |
Source |
|---|---|
| http://www.ncbi.nlm.nih.gov/pmc/articles/PMC379691 | PMC |
| http://dx.doi.org/10.1101/lm.66004 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Transcutaneous Auricular Vagus Nerve Stimulation Does Not Accelerate Fear Extinction: A Randomized, Sham-Controlled Study.
Psychophysiology
January 2025
Research Group Health Psychology, KU Leuven, Leuven, Belgium.
Transcutaneous auricular vagus nerve stimulation (taVNS) has been tested as a strategy to facilitate fear extinction learning based on the hypothesis that taVNS increases central noradrenergic activity. Four studies out of six found taVNS to enhance extinction learning especially at the beginning of extinction. Facilitatory effects of taVNS were mainly observed in US expectancy, less in fear-potentiated startle (FPS), and not in the skin conductance response (SCR).
View Article and Find Full Text PDFEffects of early maternal care on anxiety and threat learning in adolescent nonhuman primates.
Dev Cogn Neurosci
January 2025
Department of Psychiatry & Behavioral Sciences, Emory University School of Medicine, Atlanta, GA, United States; Emory National Primate Research Center, Emory University, Atlanta, GA, United States; Center for Translational Social Neuroscience, Emory University, Atlanta, GA, United States. Electronic address:
Early life adverse experiences, including childhood maltreatment, are major risk factors for psychopathology, including anxiety disorders with dysregulated fear responses. Consistent with human studies, maltreatment by the mother (MALT) leads to increased emotional reactivity in rhesus monkey infants. Whether this persists and results in altered emotion regulation, due to enhanced fear learning or impaired utilization of safety signals as shown in human stress-related disorders, is unclear.
View Article and Find Full Text PDFPersistent defensive reactivity during extensive avoidance training as a potential mechanism for the perpetuation of safety behaviors.
Sci Rep
October 2024
Department of Clinical Psychology, Experimental Psychopathology and Psychotherapy, Institute of Psychology, Philipps University Marburg, Marburg, Germany.
Safety behaviors are core features of anxiety-related disorders, specifically involving behaviors that do not completely terminate aversive situations, but rather prevent the risk of the occurrence of the expected aversive outcome (US). This study aimed to examine the dynamics of defensive reactivity associated with safety behaviors, both before and after their execution, and to investigate changes in these reactions following extensive training. Twenty-four healthy participants underwent a US-avoidance task as an experimental analog to model safety behavior, requiring a button press to avoid the US without terminating the associated warning cue (CS).
View Article and Find Full Text PDFEffects of separate and combined estradiol and progesterone administration on fear extinction in healthy pre-menopausal women.
Transl Psychiatry
October 2024
Department of Psychiatry and Neurosciences, Charité-Universitätsmedizin Berlin, corporate member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Berlin, Germany.
Altered fear conditioning and extinction learning are discussed as key etiological features in anxiety disorders. Women have an increased risk for anxiety disorders and fear conditioning has been shown to be influenced by the menstrual cycle phase and circulating gonadal hormones. The objective of our study was to investigate the effects of separate and combined estradiol and progesterone administration on fear extinction in healthy women.
View Article and Find Full Text PDFLeveraging occasional reinforced extinction via mental imagery of the unconditioned stimulus to optimize extinction learning.
Behav Res Ther
December 2024
Department of Psychology, Clinical Psychology, Experimental Psychopathology and Psychotherapy, Philipps University of Marburg, Gutenbergstraße 18, 35032, Marburg, Germany.
Occasionally presenting the unconditioned stimulus (US) during extinction training (occasional reinforced extinction, ORE) either unpaired or paired with the conditioned stimulus (CS) provides initial evidence for a less pronounced return of fear. However, translating this approach into clinical practice is challenging due to ethical and practical concerns of exposing patients to the original USs. The present study investigated extinction of fear responses in a novel approach employing ORE using vivid fear imagery of the US instead of actually exposing to it.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!