Older adults use a prefrontal regulatory mechanism to reduce negative memory vividness of a highly emotional real-world event

Abstract

Previous research has revealed an age-related shift in how individuals recall events from their personal past, with older adults reporting events that are more positive than young adults. We recently showed that age-by-valence interactions may be partially driven by a prefrontally mediated control mechanism recruited by older adults during retrieval of negative laboratory events to reduce phenomenological richness. Specifically, age was associated with greater increases in prefrontal recruitment during retrieval of negative relative to positive events, with this recruitment linked to decreases in hippocampal activity and subjective vividness ratings. In the current study, we examined whether older adults may rely on a similar mechanism during retrieval of a complex, highly emotional real-world event. Participants (n=58, age: 18-87 years) were presented with images related to the 2013 Boston Marathon Bombings and were asked to retrieve a memory associated with each image. Images cued participants with either negative (associated with fear, destruction, and sadness) or positive (images of hope, resilience, support) features. This study replicated previous episodic memory tasks: age was associated with more negative hippocampal connectivity with dorsomedial prefrontal regions during retrieval of memories triggered by negative relative to positive cues. Such findings suggest that older adults may be recruiting a similar regulatory mechanism during retrieval of both negative laboratory stimuli and highly negative events from their past. These findings are discussed in relation to previous work showing that young and older adults interact differently with the negative details related to a highly negative event.

Guiding the Emotion in Emotional Memories: The Role of the Dorsomedial Prefrontal Cortex

“…In both studies, age was also associated with a shift in how the dmPFC worked together with the hippocampus to support retrieval of negative events (Ford & Kensinger, 2018). Whereas connectivity between these two regions was positive in young adults, which suggests that the regions may work together to support memory for negative events, connectivity was negative in older adults.…”

“…The top right image shows activation associated with reduced emotional intensity of memories in young adults (Holland & Kensinger, 2013), and the lower left image shows activation corresponding with reduced vividness of older adults' negative (not positive) memories (Ford & Kensinger, 2017). The lower right image shows a dmPFC region whose activation, across two different data sets, was linked to reduced activity in the hippocampus for negative (not positive) memories (Ford & Kensinger, 2018). it well suited for executing the control and abstraction of memory representations.…”

Prefrontal contributions to the stability and variability of thought and conscious experience

“…This may imply that the dMPFC helps to coordinate the recollection of a memory through its associated emotional gist, depending upon an observer’s motivations or goals at the time of retrieval. As age increases, motivational priorities tend to shift so that negatively-valenced emotional experiences are downregulated in favor of positively-valenced ones [ 267 ], potentially accounting for the age-dependent differences in valenced memory-retrieval associated with dMPFC activation [ 266 ].…”

Age-related changes in repetition suppression of neural activity during emotional future simulation

“…Older adults also show increased dlPFC activity when processing negative stimuli (Ford, Morris, & Kensinger, 2014;Murty et al, 2009), and exhibit more habituation in dlPFC activity towards baseline over consecutive viewings of negative images (Roalf, Pruis, Stevens, & Janowsky, 2011). Moreover, older adults display increased negative functional coupling between vmPFC and amygdala (Corbett, Rajah, & Duarte, 2019;Sakaki, Nga, & Mather, 2013), and between dmPFC and the hippocampus for negative stimuli (Ford & Kensinger, 2018;Ford et al, 2014). With age, dmPFC activity is associated with decreased subjective vividness for negative memories, but increased vividness for positive memories (Ford & Kensinger, 2017).…”