The effects of emotion on retrospective duration memory using virtual reality.

Our memories for temporal duration may be colored by the emotions we experience during an event. While emotion generally enhances some aspects of memory, temporal duration has been shown to be particularly susceptible to emotion-induced distortions. However, prior work has faced difficulty when studying this phenomenon, having to make some trade-offs on ecological validity or experimental control. Here, we sought to bridge this gap by studying the effects of emotion on temporal duration memory using virtual reality. In the present study, a final sample of 69 participants experienced a series of negative-emotional and neutral worlds within virtual reality. Following this, participants provided ratings of emotionality (arousal, valence, pleasantness) and retrospective duration estimates (i.e., remembered time). We hypothesized that negative events would be recalled as having a greater duration than neutral events (H1). We additionally hypothesized that negative, but not neutral, events would be recalled as being longer than the true duration (H2). The results supported H1 while failing to provide evidence in support of H2. Together, the results bolster the importance of emotion, especially negative emotion, in shaping how we remember the temporal unfolding of the past.

The relationship between environmentally induced emotion and memory for a naturalistic virtual experience.

Emotional stimuli (e.g. words, images) are often remembered better than neutral stimuli. However, little is known about how memory is affected by an environmentally induced emotional state (without any overtly emotional occurrences) - the focus of this study. Participants were randomly assigned to discovery (n = 305) and replication (n = 306) subsamples and viewed a desktop virtual environment before rating their emotions and completing objective (i.e. item, temporal-order, duration) and subjective (e.g. vividness, sensory detail, coherence) memory measures. In both samples, a Partial Least Squares Correlation analysis showed that an emotional state characterised by high negative emotion (i.e. threat, fear, anxiety) and arousal was reliably associated with better memory in both objective (i.e. item) and subjective (i.e. vividness and sensory detail) domains. No reliable associations were observed for any temporal memory measures (objective or subjective). Thus, an environmentally induced state of negative emotion corresponds with enhanced memory for indices of episodic memory pertaining to "what" happened, but not necessarily "when" it happened.

Imagining emotional events benefits future-oriented decisions.

How does imagining future events-whether positive or negative-influence our choices in the present? Prior work has shown the simulation of hypothetical future events, dubbed episodic future thinking, can alter the propensity to engage in delay discounting (the tendency to devalue future rewards) and does so in a valence-specific manner. Some research shows that positive episodic future thinking reduces delay discounting, whereas negative future thinking augments it. However, more recent research indicates that both positive and negative episodic future thinking reduce delay discounting, suggesting an effect of episodic future thinking that is independent of valence. In this study, we sought to replicate and extend these latter findings. Here, participants (N = 604; N = 572 after exclusions) completed an online study. In the baseline task, participants completed a delay discounting task. In the experimental task, they engaged in episodic future thinking before completing a second delay discounting task. Participants were randomly assigned to engage in either positive, neutral, or negative episodic future thinking. In accordance with Bulley et al., we found that episodic future thinking, regardless of valence, reduced delay discounting. Although episodic future thinking shifted decision-making in all conditions, the effect was stronger when participants engaged in positive episodic future thinking, even after accounting for personal relevance and vividness of imagined events. These findings suggest that episodic future thinking may promote future-oriented choices by contextualising the future, and this effect is further strengthened when the future is tied to positive emotion.