autonoetic awareness and episodic memory

Much of the human experience – the way we characterize ourselves as persons – can be attributed to our episodic memory. This is the ability to travel through time, in the form of recollection, to past experiences in order to know how and why we acquired certain knowledge. Episodic memory is characterized by Endel Tulving by three qualities: sense of time, self, and autonoetic awareness. He describes it as a phenomenological quality distinct to humans, and not experienced by non-human animals. But here's where it gets hazy... it is difficult to assess whether non-human animals exercise episodic memory because they can't linguistically report their personal experiences. As such, our best shot at at studying episodic memory in non-human animal models is to assess the animal’s memory of what happened, where it happened and when it happened. Because such tests do not require a consciously directed inference to memory, they are said to assess episodic-like memory.

This consciously directed inference is what Tulving called autonoetic awareness... being the directed retrieval of a specific object of memory. This is distinct from autonoetic consciousness, which Tulving does not reference in describing episodic memory, but which is important to defining the phenomenon in non-human animals. Autonoetic consciousness has no object; rather, it is the fluid link throughout one’s past memories, present, and future projections.

Autonoetic awareness requires the use of mental time travel: reliving a targeted event of the past and using it to consider possible future scenarios. Autonoetic consciousness, because it does not require identifying the context of a specific event, does not imply mental time travel. One can conceivably travel back in time along a conscious continuum without targeting a specific time and place for an event, but knowing that it occurred somewhere in the past. For example, a person knows when and where they were born without remembering the experience. It becomes difficult to assess which of the two phenomena occurs in non-human animals because they can't declare thoughts about specific events of the past. We can't assume that because non-human animals can’t verbalize mental time travel that they do not have it, and therefore do not have autonoetic awareness. This confound requires the development of tests that allow non-human animals to declare their thoughts not with verbalization, but gesture or other physical expression.

Rhesus monkeys can appropriately refuse to submit to a visual image test when they do not think they will choose the correct answers. This test design successfully demonstrates that monkeys know when they remember a learning event or not. However, it does not directly implicate mental time travel, or presume autonoetic awareness. More likely, it suggests autonoetic consciousness - knowing that a particular piece of information is lodged somewhere in memory, but not necessarily targeting it on the streamline of consciousness. Because studies like this one more closely imply autonoetic consciousness, they support the theory of episodic-like memory, and not human-like episodic memory.

Clayton and Dickinson are pretty famous for their studies on Scrub jays argue, again, that non-human animals exhibit episodic-like memory based on an experimental design which targeted two of the three qualities of episodic memory: sense of time, and self. Clayton and Dickinson designed a caching apparatus in which scrub jays could store both preferred perishable (worms), and less preferred non-perishable (peanuts) foods. After a short period away from the caching apparatus, Scrub jays preferred to recover the worms. But... after a longer delay, they chose to recover the non-perishable although less preferred food. This fairly ingeniusly exemplifies the use of autonoetic consciousness in the birds... but in spite of its brilliant layout does not speak to autonoetic awareness.

It's worth noting that an argument could be made for the presence of autonoetic awareness in scrub jays based on their ability to distinguish between a 4hr and 124hr time period. This observation (part of the Clayton/Dickinson study) suggests that the jays were able to target a general place in time when they cached both foods so as to be able to discern that the preferred food (worm) had likely decayed since. Inferring this kind of targeting argues for autonoetic awareness... However!, it may also be the case that as with the Rhesus monkeys, the 124hr delay may have allowed scrub jays simply to forget when they cached an item. It has been shown to be the case in both rat and primates modeled in similar tasks that the memory of “when” was poorer than “what,” and “where." So... if this was the case with the scrub jays, then not being able to recall exactly when they cached the food stuff, they may have recovered the less-perishable but less preferable food simply to avoid the risk that the preferred food may have decayed. The propensity of risk averse behavior in scrub jays may give stronger baring to the argument for autonoetic consciousness than autonoetic awareness... eh?


So my last blip of this rant is this: there has been insight into the anatomical component of episodic memory in humans that may provide a link between behavioral demonstrations in humans and non-human animals. In humans, the right prefrontal cortex has been identified as a key brain region in the recall of episodic memories. Given that Clayton/Dickinson claim that their experimental design targets episodic-like memory retrieval, it would be a valuable experiment to investigate the prefrontal cortex activity in these birds as they are retrieving cached food. If the same region of the prefrontal cortex is activated during this activity, it suggests the biochemical validity of the Scrub jay findings. However, the Scrub jay is evolutionarily several orders of phylogeny removed from humans... this presents the confound of their significantly less developed prefrontal cortex. In the primate and rat models of episodic-like memory, it would be invaluable to compare a PET assessment of right prefrontal cortex activity during memory tasks. If, in the primate model, there were both a behavioral correlate in episodic-like memory tasks and activity in the right prefrontal cortex, we might be able to definitively say that animals experience episodic memory in the same way that humans do. That is, that they exercise sense of self, time and autonoetic awareness.

For now, we are only able to infer that non-human animals exhibit episodic-like memory. It remains to be concluded whether non-human animals exercise autonoetic consciousness or awareness. Determining which phenomenon is occuring will give greater insight into the behavior of non-human animals, and better address the question of whether episodic-like memory is as close to episodic memory as non-human animals get. It is entirely possible that non-human animals have only episodic-like memory because they have autonoetic consciousness, and not autonoetic awareness. However, it may also be the case that we have not found a way to enable non-human animals to declare their past experiences in a suitable way...