Behavioral Factors Governing the Extinction of Ambiguous Threat Cues
Abstract
The purpose of this experiment was to examine the cognitive mechanisms by which an animal uses associations to learn about temporally ambiguous aversive events. Traditionally, associative learning using forwards conditioning, where a conditioned stimulus (CS) presentation precedes the delivery of an unconditioned stimulus (US), and thus responses to the CS following conditioning can be attributed to the predictive value that the CS acquires. However, studies have also shown that animals acquire conditioning responses (CR) in a backwards fashion (US → CS), despite the lack of temporal information that the stimulus provides about the US (Heth 1976; Ayres et al., 1987). To examine this, in a 64-rodent study, animals were conditioned to either a forward (temporally predictable) or backward (temporally unpredictable) conditioned stimulus (CS). Following conditioning, animals were given extinction training in which they experienced repeated presentations of the CS in the absence of the US. On the final day of the experiment, the animals were returned to the original context to test whether fear to the context would be attenuated by a preceding reduction of fear to the tone. We hypothesized that the relationship between the shock stimulus and cognizance of the conditioning context will be mediated by the unpredictable tone. Analogously, the results indicated that extinguishing fear to the conditioned tone will attenuate fear to the global context fear during retrieval.
Subject
PsychologyNeuroscience
learning
memory
cognition
associative learning
Pavlovian fear conditioning
forward fear conditioning
backward fear conditioning
extinction
temporally predictability
temporally unpredictable
animal model
anxiety
PTSD
fear
Citation
Evemy, Carolyn Grace (2019). Behavioral Factors Governing the Extinction of Ambiguous Threat Cues. Undergraduate Research Scholars Program. Available electronically from https : / /hdl .handle .net /1969 .1 /194458.