Delayed extinction fails to reduce skin conductance reactivity to fear‐conditioned stimuli

Abstract

A brief 10-min time delay between an initial and subsequent exposure to extinction trials has been found to impair memory reconsolidation in fear-conditioned rodents and humans, providing a potential means to reduce fearfulness in anxiety disorders and posttraumatic stress disorder (PTSD). The present study used videos of biologically prepared, conditioned stimuli (tarantulas) to test the efficacy of delayed extinction in blocking reconsolidation of conditioned fear in healthy young adults. Strong differential conditioning, measured by skin conductance, was observed among a screened subset of participants during acquisition. However, the delayed-extinction intervention failed to reduce reactivity to the conditioned stimulus paired with the extinction delay. These results are partially consistent with other recent, mixed findings and point to a need for testing other candidate interventions designed to interfere with the reconsolidation process.

Investigação dos efeitos do comportamento verbal durante a extinção pós-recuperação sobre o retorno do medo

“…In these studies, PRE did not prevent return of fear, which led to the hypothesis that the nature of the CS would explain the divergence of results reported (and that PRE was able to prevent return of fear only when CSs were fear-irrelevant) (Fricchione et al, 2016;Kindt & Soeter, 2013;Soeter & Kindt, 2011).…”

“…Given the potential for developing a behavioral procedure that prevents the return of fear, several laboratories have attempted to replicate and extend these findings, with mixed results. In the case of studies with human participants, whereas some laboratories were able to demonstrate diminished fear responses after PRE (Agren, Engman, et al, 2012;Asthana et al, 2015;Bjorkstrand et al, 2015;Johnson & Casey, 2015;Liu et al, 2014;Oyarzún et al, 2012;Schiller, Kanen, LeDoux, Monfils, & Phelps, 2013;Schiller et al, 2010;Thompson & Lipp, 2017), there are reports of failure in producing these effects (Fricchione et al, 2016;Golkar, Bellander, Olsson, & Öhman, 2012;Kindt & Soeter, 2013;Klucken et al, 2016;Meir Drexler et al, 2014;Soeter & Kindt, 2011). These discrepancies across studies show that much work is needed to fully understand the variables and specific parameters involved in the 2 Like the term extinction, spontaneous recovery, renewal and reinstatement are terms that can either refer to procedures (for example, the presentation of the CS in a context different from where extinction took place, as in renewal) or processes (elicitation of conditioned responses after one of these procedures).…”

“…However, it is also common for experimenters to utilize spontaneous recovery (presentations of the CS after some time has passed since extinction) or renewal (presentations of the CS in a different context than the setting where extinction took place) tests. In these tests, return of fear is assessed by comparing responses to the CSs (CS+s and CS-) at the end of extinction (last trial or a block of trials at the end of the session) with responses to the CSs at the beginning of the test (first trial or first block of trials) (Asthana et al, 2015;Bjorkstrand et al, 2015;Kindt & Soeter, 2013;Klucken et al, 2016;Oyarzún et al, 2012;Schiller et al, 2013Schiller et al, , 2010 or by comparing responses to the different CSs in the test (CS+ vs. CS-) (Fricchione et al, 2016;Golkar et al, 2012;Golkar, Tjaden, & Kindt, 2017;Thompson & Lipp, 2017). In some cases, only responses to the CS+ at the end of extinction are compared with responses to the CS+ at the beginning of the test (Johnson & Casey, 2015;Meir Drexler et al, 2014;Warren et al, 2014).…”

“…The reinforcement rate during conditioning (i.e., the proportion of CS trials ending with the US) has been referred to as a variable that might change the probability of return of fear after PRE (Fricchione et al, 2016;Golkar et al, 2012;Kindt & Soeter, 2013;Oyarzún et al, 2012;Soeter & Kindt, 2011;Warren et al, 2014). The first two studies showing diminished return of fear after PRE utilized low reinforcement rates during conditioning (38% in Schiller et al, 2010, andOyárzun et al, 2012), whereas some experiments reporting failure to produce these effects were conducted with higher reinforcement rates (75% in Soeter, 2013, and80% in Soeter andKindt, 2011).…”

“…(2010) utilized colored squares as CSs, which are thought to be fear-irrelevant and less likely to be associated with anxiety in real life (Golkar et al, 2012(Golkar et al, , 2017Kindt & Soeter, 2013;Kindt, Soeter, & Vervliet, 2009;Soeter & Kindt, 2011). Some authors utilized fear-relevant stimuli as CSs, such as pictures or high definition video-clips of potentially dangerous animals, such as tigers, dogs, snakes, spiders (Fricchione et al, 2016;Kindt & Soeter, 2013;Meir Drexler et al, 2014;Soeter & Kindt, 2011), or fearful male faces (Golkar et al, 2012).…”