Comparing the non-linguistic hallmarks of episodic memory systems in corvids and children

The Ape That Lived to Tell the Tale. The Evolution of the Art of Storytelling and Its Relationship to Mental Time Travel and Theory of Mind

Engaging in the art of creating and telling stories is a defining behaviour of humankind. Humans have been sharing stories with each other, with and without words, since the dawn of recorded history, but the cognitive foundations of the behaviour can be traced deeper into our past. The emergence of stories can be strongly linked to Mental Time Travel (the ability to recall the past and imagine the future) and plays a key role in our ability to communicate past, present and future scenarios with other individuals, within and beyond our lifetimes. Stories are products engraved within the concept of time, constructed to elucidate the past experiences of the self, but designed with the future in mind, thus imparting lessons of such experiences to the receiver. By being privy to the experiences of others, humans can imagine themselves in a similar position to the protagonist of the story, thus mentally learning from an experience they might have never encountered other than in the mind's eye. Evolutionary Psychology investigates how the engagement in artistic endeavours by our ancestors in the Pleistocene granted them an advantage when confronted with obstacles that challenged their survival or reproductive fitness and questions whether art is an adaptation of the human mind or a spandrel of other cognitive adaptations. However, little attention has been placed on the cognitive abilities that might have been imperative for the development of art. Here, we examine the relationship between art, storytelling, Mental Time Travel and Theory of Mind (i.e., the ability to attribute mental states to others). We suggest that Mental Time Travel played a key role in the development of storytelling because through stories, humans can fundamentally transcend their present condition, by being able to imagine different times, separate realities, and place themselves and others anywhere within the time space continuum. We argue that the development of a Theory of Mind also sparked storytelling practises in humans as a method of diffusing the past experiences of the self to others whilst enabling the receiver to dissociate between the past experiences of others and their own, and to understand them as lessons for a possible future. We propose that when artistic products rely on storytelling in form and function, they ought to be considered separate from other forms of art whose appreciation capitalise on our aesthetic preferences.

Dimensions of Animal Consciousness

How does consciousness vary across the animal kingdom? Are some animals 'more conscious' than others? This article presents a multidimensional framework for understanding interspecies variation in states of consciousness. The framework distinguishes five key dimensions of variation: perceptual richness, evaluative richness, integration at a time, integration across time, and self-consciousness. For each dimension, existing experiments that bear on it are reviewed and future experiments are suggested. By assessing a given species against each dimension, we can construct a consciousness profile for that species. On this framework, there is no single scale along which species can be ranked as more or less conscious. Rather, each species has its own distinctive consciousness profile.

Temporal Junctures in the Mind

Humans can imagine what happened in the past and what will happen in the future, but also what did not happen and what might happen. We reflect on envisioned events from alternative timelines, while knowing that we only ever live on one timeline. Considering alternative timelines rests on representations of temporal junctures, or points in time at which possible versions of reality diverge. These representations become increasingly sophisticated over childhood, first enabling preparation for mutually exclusive future possibilities and later the experience of counterfactual emotions like regret. By contrast, it remains unclear whether non-human animals represent temporal junctures at all. The emergence of these representations may have been a prime mover in human evolution.

Long-Term Memory of Past Events in Great Apes

It has been claimed that the ability to recall personal past events is uniquely human. We review recent evidence that great apes can remember specific events for long periods of time, spanning months and even years, and that such memories can be enhanced by distinctiveness (irrespective of reinforcement) and follow a forgetting curve similar to that in humans. Moreover, recall is enhanced when apes are presented with features that are diagnostic of the event, consistent with notions of encoding specificity and cue overload in human memory. These findings are also consistent with the involuntary retrieval of past events in humans, a mode of remembering that is thought to be less cognitively demanding than voluntary retrieval. Taken together, these findings reveal further similarities between the way humans and animals remember past events and open new avenues of research on long-term memory in nonhuman animals.

Children's behavior and spontaneous talk in a future thinking task

We explored 3-, 4-, and 5-year-olds' (N = 120) "explicit" and "spontaneous" future-oriented cognition. Specifically, children had to think ahead to meet a future physiological need (desire for food) or psychological need (avoiding boredom). One group of children alternated between a room with candy and a room without candy, spending 3 min per visit. Children were explicitly asked which room they wanted to put extra candy in for a future visit to the lab (correct answer: room without candy). A second group of children underwent the same procedure but with toys as the resource instead of food (a replication of Atance et al. in J Exp Child Psychol 129:98-109, 2015). In the food condition, 3-, 4-, and 5-year-olds all placed candy in the correct room above chance, but only 4- and 5-year-olds were above chance in the toy condition. Overall, 4- and 5-year-olds outperformed 3-year-olds, and children performed better in the food condition than the toy condition. Children's spontaneous (or "involuntary") future thinking was assessed by coding their utterances while in the two rooms. Children who solved the explicit task uttered more task-relevant future and past statements than children who failed. Examining spontaneous talk also allowed us to explore children's spontaneous "solving" of the task before being asked an explicit test question. This research highlights the importance of varying stimuli in future thinking tasks and developing methods to capture spontaneous/involuntary future thinking in young children.