In the target article, Mahr & Csibra (M&C) challenge overly cognitive accounts of episodic memory based on the mental time travel metaphor. Instead, they offer a social-cognitive function of episodic memory in terms of an epistemic attitude that signals testimonial authority in human communications. I applaud the proposed shift in focus toward the social-cognitive functions of episodic memory, and I suspect that M&C's suggestion may not be the only function of episodic memory in the social domain.
M&C also propose a distinction between event and episodic memory. As they mention, and as I have argued elsewhere (Keven Reference Keven2016b), the distinction has the potential to resolve the long-lasting debate about whether episodic memory is a uniquely human capacity. If the distinction is proven to be robust, we can understand the mnemonic abilities of young children and nonhuman animals with event memory without ascribing to them a capacity for full-blown episodic memory. However, it is not clear how to distinguish event and episodic memory at this stage. M&C suggest that event and episodic memory share the same scenario construction process, whereas I think the type of construction involved in episodic memory is different in kind from that of event memory. We can distinguish at least four different types of organization that could be utilized in memory reconstructions:
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1.
Spatial organization: We perceive the world in a spatially organized way and can recall our experiences as such.
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2.
Temporal organization: Experiences occur sequentially in time, such as before or after another event. When we reconstruct an experience from memory, the events should occur in their proper place in the sequence.
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3.
Causal organization: Events can be distant in time and yet can have causal connections with each other. I remember that I missed my bus to Istanbul because my alarm didn't ring. Missing the bus and the malfunctioning alarm clock are two temporally distant events that are causally connected in my memory reconstruction.
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4.
Teleological organization: Temporally distant and causally disparate events can still be connected with each other based on goals. For instance, I remember that I was going to give a talk when I missed the bus, so I took a plane instead to get there in time. Although giving a talk is temporally distant and causally disparate from the malfunctioning alarm clock and missing the bus, it is still connected to them in my memory as my goal at the time.
In M&C's view, both event and episodic memory involve construction of a scenario that involves simulation of events that are extended in time and space. It is not clear whether these simulations involve all of these four types of organization. If they want to maintain that young children and other nonhuman animals have event memories, however, then there have to be some differences in the construction of event and episodic memories. Even though there is some evidence that nonhuman animals can be sensitive to temporal information (e.g., Babb & Crystal Reference Babb and Crystal2006; Clayton & Dickinson Reference Clayton and Dickinson1998), it is far from clear whether this amounts to an ability to temporally sequence events into before and after relations (McCormack & Hoerl Reference McCormack, Hoerl, McCormack, Hoerl and Butterfill2011; Roberts & Feeney Reference Roberts and Feeney2009). Moreover, causal understanding of our primate cousins is very limited, and no nonhuman animals seem to understand the behavior of others in terms of goals (Penn & Povinelli Reference Penn and Povinelli2007; Penn et al. Reference Penn, Holyoak and Povinelli2008; Povinelli Reference Povinelli2000; Tomasello et al. Reference Tomasello, Carpenter, Call, Behne and Moll2005; Visalberghi & Tomasello Reference Visalberghi and Tomasello1998). Similarly, young children show less temporal sequence knowledge and omit causal relations between events in their recall of novel experiences, and their memory representations are not organized around goals to the same extent as are older children's and adults (e.g., Price & Goodman Reference Price and Goodman1990; Ratner et al. Reference Ratner, Smith and Dion1986). So, it is unlikely that event memories in young children and nonhuman animals can involve temporal, causal, and teleological organization.
In earlier work (Keven Reference Keven2016b), I provided evidence and argued in favor of carving up event and episodic memory in a different way. According to the dual systems thesis that I proposed, event memory is a snapshot-like memory system based on perceptual processes predominantly in the form of visual images. These perceptually grounded representations are highly accurate but short-lived. Construed as such, event memories involve only spatial organization. Any other type of organization is not necessary in this case, as there are no series of events that are extended in space and time.
However, construction of episodic memories requires a higher order inferential process. Episodes generally consist of a series of events that are extended across different times and places. When I remember the missing-the-bus episode, I don't remember all of the minute details involved in the actual experience; I remember only the causally and teleologically relevant ones in the right temporal order. To connect such a series of events, the construction process needs to sort the events into cause and effect and goal-attempt-outcome relations, besides keeping track of each scene's spatial structure and the event's temporal order. Organizing memories in this way requires making higher-order inferences on the relations between events from memory as these relations are not directly observable. According to the dual systems thesis, this inferential process is closely tied to our storytelling capacity as narrative has nearly all of the organizational components one would expect. Reconstructing a narrative version of the experience provides the required temporal, causal, and teleological organization. As such, episodic memories are lower in accuracy but can span longer timescales and are more memorable.
To sum up, when we consider different types of organization that can be utilized in memory reconstructions, construction of event and episodic memories differ in kind. In particular, the construction of episodic memories requires a higher-order inferential process, which is unlikely to be found in event memories.
In the target article, Mahr & Csibra (M&C) challenge overly cognitive accounts of episodic memory based on the mental time travel metaphor. Instead, they offer a social-cognitive function of episodic memory in terms of an epistemic attitude that signals testimonial authority in human communications. I applaud the proposed shift in focus toward the social-cognitive functions of episodic memory, and I suspect that M&C's suggestion may not be the only function of episodic memory in the social domain.
M&C also propose a distinction between event and episodic memory. As they mention, and as I have argued elsewhere (Keven Reference Keven2016b), the distinction has the potential to resolve the long-lasting debate about whether episodic memory is a uniquely human capacity. If the distinction is proven to be robust, we can understand the mnemonic abilities of young children and nonhuman animals with event memory without ascribing to them a capacity for full-blown episodic memory. However, it is not clear how to distinguish event and episodic memory at this stage. M&C suggest that event and episodic memory share the same scenario construction process, whereas I think the type of construction involved in episodic memory is different in kind from that of event memory. We can distinguish at least four different types of organization that could be utilized in memory reconstructions:
1. Spatial organization: We perceive the world in a spatially organized way and can recall our experiences as such.
2. Temporal organization: Experiences occur sequentially in time, such as before or after another event. When we reconstruct an experience from memory, the events should occur in their proper place in the sequence.
3. Causal organization: Events can be distant in time and yet can have causal connections with each other. I remember that I missed my bus to Istanbul because my alarm didn't ring. Missing the bus and the malfunctioning alarm clock are two temporally distant events that are causally connected in my memory reconstruction.
4. Teleological organization: Temporally distant and causally disparate events can still be connected with each other based on goals. For instance, I remember that I was going to give a talk when I missed the bus, so I took a plane instead to get there in time. Although giving a talk is temporally distant and causally disparate from the malfunctioning alarm clock and missing the bus, it is still connected to them in my memory as my goal at the time.
In M&C's view, both event and episodic memory involve construction of a scenario that involves simulation of events that are extended in time and space. It is not clear whether these simulations involve all of these four types of organization. If they want to maintain that young children and other nonhuman animals have event memories, however, then there have to be some differences in the construction of event and episodic memories. Even though there is some evidence that nonhuman animals can be sensitive to temporal information (e.g., Babb & Crystal Reference Babb and Crystal2006; Clayton & Dickinson Reference Clayton and Dickinson1998), it is far from clear whether this amounts to an ability to temporally sequence events into before and after relations (McCormack & Hoerl Reference McCormack, Hoerl, McCormack, Hoerl and Butterfill2011; Roberts & Feeney Reference Roberts and Feeney2009). Moreover, causal understanding of our primate cousins is very limited, and no nonhuman animals seem to understand the behavior of others in terms of goals (Penn & Povinelli Reference Penn and Povinelli2007; Penn et al. Reference Penn, Holyoak and Povinelli2008; Povinelli Reference Povinelli2000; Tomasello et al. Reference Tomasello, Carpenter, Call, Behne and Moll2005; Visalberghi & Tomasello Reference Visalberghi and Tomasello1998). Similarly, young children show less temporal sequence knowledge and omit causal relations between events in their recall of novel experiences, and their memory representations are not organized around goals to the same extent as are older children's and adults (e.g., Price & Goodman Reference Price and Goodman1990; Ratner et al. Reference Ratner, Smith and Dion1986). So, it is unlikely that event memories in young children and nonhuman animals can involve temporal, causal, and teleological organization.
In earlier work (Keven Reference Keven2016b), I provided evidence and argued in favor of carving up event and episodic memory in a different way. According to the dual systems thesis that I proposed, event memory is a snapshot-like memory system based on perceptual processes predominantly in the form of visual images. These perceptually grounded representations are highly accurate but short-lived. Construed as such, event memories involve only spatial organization. Any other type of organization is not necessary in this case, as there are no series of events that are extended in space and time.
However, construction of episodic memories requires a higher order inferential process. Episodes generally consist of a series of events that are extended across different times and places. When I remember the missing-the-bus episode, I don't remember all of the minute details involved in the actual experience; I remember only the causally and teleologically relevant ones in the right temporal order. To connect such a series of events, the construction process needs to sort the events into cause and effect and goal-attempt-outcome relations, besides keeping track of each scene's spatial structure and the event's temporal order. Organizing memories in this way requires making higher-order inferences on the relations between events from memory as these relations are not directly observable. According to the dual systems thesis, this inferential process is closely tied to our storytelling capacity as narrative has nearly all of the organizational components one would expect. Reconstructing a narrative version of the experience provides the required temporal, causal, and teleological organization. As such, episodic memories are lower in accuracy but can span longer timescales and are more memorable.
To sum up, when we consider different types of organization that can be utilized in memory reconstructions, construction of event and episodic memories differ in kind. In particular, the construction of episodic memories requires a higher-order inferential process, which is unlikely to be found in event memories.