Emotional state dynamics impacts temporal memory

ABSTRACT

Emotional fluctuations are ubiquitous in everyday life, but precisely how they sculpt the temporal organisation of memories remains unclear. Here, we designed a novel task – the Emotion Boundary Task – wherein participants viewed sequences of negative and neutral images surrounded by a colour border. We manipulated perceptual context (border colour), emotional-picture valence, as well as the direction of emotional-valence shifts (i.e., shifts from neutral-to-negative and negative-to-neutral events) to create events with a shared perceptual and/or emotional context. We measured memory for temporal order and temporal distances for images processed within and across events. Negative images processed within events were remembered as closer in time compared to neutral ones. In contrast, temporal distances were remembered as longer for images spanning neutral-to-negative shifts – suggesting temporal dilation in memory with the onset of a negative event following a previously-neutral state. The extent of negative-picture induced temporal dilation in memory correlated with dispositional negativity across individuals. Lastly, temporal order memory was enhanced for recently-presented negative (versus neutral) images. These findings suggest that emotional-state dynamics matters when considering emotion-temporal memory interactions: While persistent negative events may compress subjectively remembered time, dynamic shifts from neutral-to-negative events produce temporal dilation in memory, with implications for adaptive emotional functioning.

KEYWORDS:

• Temporal memory
• emotion
• event boundary
• psychopathology

Acknowledgments

The authors thank Mengsi Li, Joanne Stasiak, and Reicher Bergstein for helpful discussions and assistance with manuscript preparation, and Zishi Ding and Mia Jeffery for assistance with data collection. The authors also thank Drs. Ioannis Pappas and Ian Ballard for helpful resources and discussion of image similarity metrics.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Notes

1 In the current and similar studies, temporal dilation is referred as an increase of remembered temporal distance between conditions – relative to the average temporal distance observed in the study and/or relative to the temporal distance observed in other conditions – whereas temporal compression refers to a relative decrease in temporal distance.

2 The emotional manipulation in the current study was anchored on normative ratings of emotional valence, which were used to select negative vs. neutral pictures – we refer to this dimension as “emotional-valence” following the conventional nomenclature in IAPS studies (Lang et al., 2008; Lang & Bradley, 2007). However, note that negative emotional pictures that are low in valence inherently differ from neutral pictures in both valence and arousal dimensions.

3 Note that because the temporal intervals between the sampled images were fixed, changes in temporal distance estimates reflect changes in subjectively remembered time.

4 Due to the relatively low loading of ATQ scores in the originally planned factor analysis, we also calculated the correlation between temporal memory dilation and dispositional negativity factor scores obtained after excluding the ATQ. This analysis replicated our results, with higher dispositional negativity correlating positively with the magnitude of temporal memory dilation across individuals (r = 0.248, p = 0.026).

5 Note that similar results were obtained following residualization procedures using the other available conditions – namely, after residualizing temporal distance memory for [Neu-to-Neg] event transitions for [Neu-to-Neu] (r(78)=0.197, p=0.080) or [Neg-to-Neg] r(78) = 0.236, p = 0.035) transitions.

Additional information

Funding

This work was supported by an Academic Senate Faculty Research grant from the University of California, Santa Barbara (R.C.L) and National Institute of Mental Health Grant R01-MH134000 (R. C. L).