Context-dependent extinction of threat memories: influences of healthy aging

Abstract

Although a substantial progress has been made in recent years on understanding the processes mediating extinction of learned threat, little is known about the context-dependent extinction of threat memories in elderly individuals. We used a 2-day differential threat conditioning and extinction procedure to determine whether young and older adults differed in the contextual recall of conditioned responses after extinction. On Day 1, conditioned stimuli were paired with an aversive electric shock in a ‘danger’ context and then extinguished in a different ‘safe’ context. On Day 2, the extinguished stimulus was presented to assess extinction recall (safe context), and threat renewal (danger context). Physiological and verbal report measures of threat conditioning were collected throughout the experiment. Skin conductance response (SCR data revealed no significant differences between age groups during acquisition and extinction of threat conditioning on Day 1. On Day 2, however, older adults showed impaired recall of extinction memory, with increased SCR to the extinguished stimulus in the ‘safe’ context, and reduced ability to process context properly. In addition, there were no age group differences in fear ratings and contingency awareness, thus revealing that aging selectively impairs extinction memories as indexed by autonomic responses. These results reveal that aging affects the capacity to use context to modulate learned responses to threat, possibly due to changes in brain structures that enable context-dependent behaviour and are preferentially vulnerable during aging.

Subliminal determinants of cue-guided choice

“…The prevalence of automatic responding is indeed generally associated with addictive, impulsive, and obsessive traits 34 39 , 44 – 47 . In this sense, the lack of conscious processing that characterizes general transfer could potentially be a marker of vulnerability to maladaptive forms of cue-guided choices 3 . In the case of addiction, for example, although no direct correlation between drug or food forms of addiction and outcome-specific transfer has been reported in literature 48 , 49 , it cannot be excluded that this is instead related to forms of cue-driven choice requiring a lower level of processing, like in the case of general transfer 50 .…”

“…In everyday life, environmental cues can anticipate the presence of potential rewards, or punishments, thus biasing choice (i.e., cue-guided choices). Although evidence shows that the mere presence of reward-associated cues can influence individual choice [2][3][4] , the boundary conditions within which this occurs remain unknown. In particular, it is not clear whether the conscious elaboration of such cues is necessary to elicit cue-guided choices 5,6 .…”

Individual differences in working memory capacity and cue-guided behavior in humans

“…With instrumental conditioning, we learn to predict the consequences of a given action, whereas with Pavlovian conditioning we learn to predict the consequences associated with the presence of external cues. Information gathered via such learning processes, even if independently acquired, can be integrated to guide behaviour 2–4 . An example of this mechanism can be observed in the Pavlovian-to-Instrumental Transfer (PIT) effect, which tests the extent to which a Pavlovian stimulus (S) can drive instrumental responses (R) independently paired with the same or a similar outcome (O).…”

Salience and default‐mode network connectivity during threat and safety processing in older adults

“…Threat and safety learning are most commonly assessed by measuring psychophysiological signals of arousal, such as the skin conductance response, which indicate the sympathetic nervous system's defensive response to direct, impending threat. Previous studies investigating threat conditioning in older adults have shown no age‐related differences in older adults' behavioural or psychophysiological differential responses to conditioned stimuli beyond a general reduction in arousal (Battaglia, Garofalo, & di Pellegrino, 2018; LaBar, Cook, Torpey, & Welsh‐Bohmer, 2004; Rosenbaum et al, 2015). However, the absence of behavioural and psychophysiological differences does not necessarily imply the absence of neural differences.…”