The organization of prospective thinking: Evidence of event clusters in freely generated future thoughts

Recent research suggests that many imagined future events are not represented in isolation, but instead are embedded in broader event sequences—referred to as event clusters. It remains unclear, however, whether the production of event clusters reflects the underlying organizational structure of prospective thinking or whether it is an artifact of the event-cuing task in which participants are explicitly required to provide chains of associated future events. To address this issue, the present study examined whether the occurrence of event clusters in prospective thought is apparent when people are left to think freely about events that might happen in their personal future. The results showed that the succession of events participants spontaneously produced when envisioning their future frequently included event clusters. This finding provides more compelling evidence that prospective thinking involves higher-order autobiographical knowledge structures that organize imagined events in coherent themes and sequences.     

Eye movements disrupt episodic future thinking

Remembering the past and imagining the future both rely on complex mental imagery. We considered the possibility that constructing a future scene might tap a component of mental imagery that is not as critical for remembering past scenes. Whereas visual imagery plays an important role in remembering the past, we predicted that spatial imagery plays a crucial role in imagining the future. For the purpose of teasing apart the different components underpinning scene construction in the two experiences of recalling episodic memories and shaping novel future events, we used a paradigm that might selectively affect one of these components (i.e., the spatial). Participants performed concurrent eye movements while remembering the past and imagining the future. These concurrent eye movements selectively interfere with spatial imagery, while sparing visual imagery. Eye movements prevented participants from imagining complex and detailed future scenes, but had no comparable effect on the recollection of past scenes. Similarities between remembering the past and imagining the future are coupled with some differences. The present findings uncover another fundamental divergence between the two processes.     

How great is great ape foresight?

Osvath and Osvath (Anim Cogn 11: 661–674, 2008) report innovative studies with two chimpanzees and one orangutan that suggest some capacity to select and keep a tool for use about an hour later. This is a welcome contribution to a small, but rapidly growing, field. Here we point out some of the weaknesses in the current data and caution the interpretation the authors advance. It is not clear to what extent the apes really engaged in any foresight in these studies. This is an invited response to Osvath and Osvath (2008).     

Mental time travel: Effects of trial duration on episodic and semantic content

Studies exploring mental time travel commonly use cue-word paradigms to elicit past and future autobiographical events. However, the effect of trial duration (how long participants are allowed to describe events) on the relationship between episodic and nonepisodic detail and episodic specificity (i.e., whether longer durations increase event specificity) has not been examined. To resolve these issues, a cue-word study was devised whereby participants described past and future events under three randomly administered time constraints: short (1-min), standard (3-min), and long (5-min) durations. Findings indicated that an individual's capacity for episodic and nonepisodic thought for the past and future were unrelated. This lends supports to the idea that independent mechanisms are responsible for episodic and semantic information. This study also offers clarity concerning the effect of different trial durations on episodic specificity, which may aid the design of future studies of mental time travel.