Abstract: People and other animals can search for information inside their heads. Where does this ability come from, and what does it enable cognitive systems to do? In this article, we address the behavioral and cognitive similarities between search in external environments and internal environments (e.g., memory). These require both maplike representations and the means to navigate them, and the latter involves modulation between exploitation and exploration analogous to a foraging process called area-restricted search. These findings have implications for understanding a number of cognitive abilities commonly considered to be hallmarks of the human species, such as well-developed executive control and goal-directed cognition, autonoetic consciousness (i.e., self-awareness), deliberation, and free will. Moreover, this research extends our conception of what organisms may share these abilities and how they evolved.
Keywords: search, foraging, memory, executive function, verbal fluency task, cognitive map, episodic future thinking, self-projection
---
Deliberation and self-projection
Deliberation can be defined as the ability to consider alternative courses of action. This can be instantiated as a form of internal foraging and is sometimes associated with the capacity for self-projection, imagining oneself adopting each considered course of action (or mental time travel; see Suddendorf, Addis, & Corballis, 2009). Studies with nonhuman animals have demonstrated phenomenological properties of deliberation. Recordings from hippocampal place cells in rats have shown preemptive internal foraging of choices of directions to take when navigating a maze, with hippocampal activation being followed by activation in striatal reward centers, allowing the valuing of possible future actions (Pezzulo, van der Meer, Lansink, & Pennartz, 2014; see Redish, 2016, for a review). This is called episodic future thinking, and alongside the increasing evidence for episodic memory in nonhuman animals (reviewed by Crystal, 2018), it suggests that internal foraging allows human and nonhuman animals to consider multiple courses of actions before initiating a choice. Perhaps most importantly for establishing humanlike abilities in other species (Suddendorf et al., 2009), internal foraging in nonhuman animals demonstrates the capacity for generativity, producing novel goal-directed solutions that the animal has never experienced before (Gupta, van der Meer, Touretzky, & Redish, 2010; Pfeiffer & Foster, 2013).
Self-awareness and autonoetic consciousness
Internal search requires two closely linked processes ( Jones et al., 2015): (a) a representation of the information to be searched along with some instantiation of nearness and farness, what Tolman (1948) referred to as a cognitive map, and (b) an attentional search process that controls or guides progress through the internal map. The goal-directed search process is associated with executive function and goal maintenance (Hills et al., 2010) and is synonymous with effortful consciousness, the kind of thinking associated with focused attention, one-thing-at-a-time processing, the ability to produce novelty, and self-report (e.g., Baddeley, 2007).
But internal search may also require another kind of consciousness. Any computational system (animal, robotic, or extraterrestrial) that develops an information representation and the capacity to search over it should also be able to tell the difference between internally imagined “experiences” (generated by episodic future thinking) and real experiences, or the individual will likely suffer from false memories and hallucinations. Hills and Butterfill (2015) argued that the need for this discriminative ability between internal and external foraging provides an evolutionary foothold for selfawareness, similar to what Tulving (1985) described as autonoetic consciousness.
Debates about self-awareness in animals are ongoing and have often relied on mirror self-recognition tasks using the mark test. Researchers have now observed that this task can be solved by primates, dolphins, elephants, chimpanzees, corvids, and more recently, fish. The prediction from internal-foraging research is that selfawareness, whether signaled by self-recognition or not, should be found in animals with the capacity to forage in mind as part of the mechanism that distinguishes between internal and external foraging events and thereby prevents memory errors and associated costly behaviors. (The presence of self-recognition could be an indication that a species engages in internal foraging, but this is not necessarily the case given that self-recognition may have evolved for other purposes.)
Free will and generative self-construction
Free will may at first seem beyond the scope of naturalistic accounts of cognitive capacities. But among compatibilists—people allowing for free will in a deterministic universe—standard requirements for free will include the capacity to “do otherwise” (to take alternative courses of action), to maintain goals, to deliberate over alternatives (internal foraging) in pursuit of said goals, and in the end, to be able to say “I did it” (Dennett, 2015). As our arguments above indicate, internal search and its required processes satisfy what many philosophers have characterized as these design features of compatibilist free will.
In particular, capacities for self-projection and generation of novelty in episodic future thinking lead to the possibility of generative self-construction (Hills, 2019). This involves a cognitive system, consciously aware of its own internal foraging, that experiences future versions of itself via constructive memory processes that sample from and recombine past experiences, chooses among them on the basis of the expected values associated with those experiences, and then acts to bring the chosen one about. This generative selfconstruction is a pragmatic and computational conceptualization of free will because it is built from the evolutionarily adaptive components underlying internal foraging mechanisms.
No comments:
Post a Comment