Visual working memory is a construct hypothesized to store a small amount of accurate perceptual information that can be brought to bear on a task. Much research concerns the construct's capacity and the precision of the information stored. Two prominent theories of VWM representation have emerged: slot-based and continuous-resource mechanisms. Prior modeling work suggests that a continuous resource that varies over trials with variable capacity and a potential to make localization errors best accounts for the empirical data. Questions remain regarding (...) the variability in VWM capacity and precision. Using a novel eye-tracking paradigm, we demonstrate that VWM facilitates search and exhibits effects of fixation frequency and recency, particularly for prior targets. Whereas slot-based memory models cannot account for the human data, a novel continuous-resource model does capture the behavioral and eye tracking data, and identifies the relevant resource as item activation. (shrink)

Working memory is the system responsible for maintaining and manipulating information, in the face of ongoing distraction. In turn, WM span is perceived to be an individual-differences construct reflecting the limited capacity of this system. Recently, however, there has been some evidence to suggest that WM capacity can increase through training, raising the possibility that training can functionally alter the neural structures supporting WM. To address the hypothesis that the neural substrates underlying WM are targeted by training, we conducted a (...) meta-analysis of functional magnetic resonance imaging studies of WM training using Activation Likelihood Estimation. Our results demonstrate that WM training is associated exclusively with decreases in blood oxygenation level-dependent responses in clusters within the fronto-parietal system that underlie WM, including the bilateral inferior parietal lobule, middle and superior frontal gyri, and medial frontal gyrus bordering on the cingulate gyrus. We discuss the various psychological and physiological mechanisms that could be responsible for the observed reductions in the BOLD signal in relation to WM training, and consider their implications for the construct of WM span as a limited resource. (shrink)

Several studies have shown that our visual system may construct a “summary statistical representation” over groups of visual objects. Although there is a general understanding that human observers can accurately represent sets of a variety of features, many questions on how summary statistics, such as an average, are computed remain unanswered. This study investigated sampling properties of visual information used by human observers to extract two types of summary statistics of item sets, average and variance. We presented three models of (...) ideal observers to extract the summary statistics: a global sampling model without sampling noise, global sampling model with sampling noise, and limited sampling model. We compared the performance of an ideal observer of each model with that of human observers using statistical efficiency analysis. Results suggest that summary statistics of items in a set may be computed without representing individual items, which makes it possible to discard the limited sampling account. Moreover, the extraction of summary statistics may not necessarily require the representation of individual objects with focused attention when the sets of items are larger than 4. (shrink)

In the current paper, we articulate a theory to explain the phenomenology of mental effort. The theory provides a working definition of mental effort, explains in what sense mental effort is a limited resource, and specifies the factors that determine whether or not mental effort is experienced as aversive. The core of our theory is the conjecture that the sense of effort is the output of a cost-benefit analysis. This cost-benefit analysis employs heuristics to weigh the current and anticipated costs (...) of mental effort for a particular activity against the anticipated benefits. This provides a basis for spelling out testable predictions to structure future research on the phenomenology of mental effort. (shrink)

We conducted a computer-based psychological experiment in which a random mix of 40 tautologies and 40 non-tautologies were presented to the participants, who were asked to determine which ones of the formulas were tautologies. The participants were eight university students in computer science who had received tuition in propositional logic. The formulas appeared one by one, a time-limit of 45 s applied to each formula and no aids were allowed. For each formula we recorded the proportion of the participants who (...) classified the formula correctly before timeout and the mean response time among those participants. We propose a new proof formalism for modeling propositional reasoning with bounded cognitive resources. It models declarative memory, visual memory, working memory, and procedural memory according to the memory model of Atkinson and Shiffrin and reasoning processes according to the model of Newell and Simon. We also define two particular proof systems, T and NT, for showing propositional formulas to be tautologies and non-tautologies, respectively. The accuracy was found to be higher for non-tautologies than for tautologies ( p T was.89 and for non-tautologies the correlation between latency and minimum proof length in NT was.87. (shrink)

Hilary Kornblith argues that many traditional philosophical accounts involve problematic views of reflection. According to Kornblith, reflection does not add reliability, which makes it unfit to underlie a separate form of knowledge. We show that a broader understanding of reflection, encompassing Type 2 processes, working memory, and episodic long-term memory, can provide philosophy with elucidating input that a restricted view misses. We further argue that reflection in fact often does add reliability, through generalizability, flexibility, and creativity that is helpful in (...) newly encountered situations, even if the restricted sense of both reflection and knowledge is accepted. And so, a division of knowledge into one reflexive form and one reflective form remains a plausible, and possibly fruitful, option. (shrink)

Hilary Kornblith argues that many traditional philosophical accounts involve problematic views of reflection (understood as second-order mental states). According to Kornblith, reflection does not add reliability, which makes it unfit to underlie a separate form of knowledge. We show that a broader understanding of reflection, encompassing Type 2 processes, working memory, and episodic long-term memory, can provide philosophy with elucidating input that a restricted view misses. We further argue that reflection in fact often does add reliability, through generalizability, flexibility, and (...) creativity that is helpful in newly encountered situations, even if the restricted sense of both reflection and knowledge is accepted. And so, a division of knowledge into one reflexive (animal) form and one reflective form remains a plausible, and possibly fruitful, option. (shrink)

Autobiographical–episodic memory is the conjunction of subjective time, autonoetic consciousness and the experiencing self. Understanding the neural correlates of autobiographical–episodic memory might therefore be essential for shedding light on the neurobiology underlying the experience of being an autonoetic self. In this contribution we illustrate the intimate relationship between autobiographical–episodic memory and self by reviewing the clinical and neuropsychological features and brain functional imaging correlates of psychogenic amnesia – a condition that is usually characterized by severely impaired retrograde memory functioning, in (...) absence of structural brain damage as detected by standard imaging. We demonstrate that in this disorder the autobiographical–episodic memory deficits do not exist in isolation, but occur with impairments of the autonoetic self-consciousness, emotional processing, and theory of mind or executive functions. Furthermore functional and metabolic brain alterations involving regions that are agreed upon to exert crucial roles in memory processes were frequently found to accompany the psychogenic memory “loss”. (shrink)

We present a framework for epistemic logic, modeling the logical aspects of System 1 and System 2 cognitive processes, as per dual process theories of reasoning. The framework combines non-normal worlds semantics with the techniques of Dynamic Epistemic Logic. It models non-logically-omniscient, but moderately rational agents: their System 1 makes fast sense of incoming information by integrating it on the basis of their background knowledge and beliefs. Their System 2 allows them to slowly, step-wise unpack some of the logical consequences (...) of such knowledge and beliefs, by paying a cognitive cost. The framework is applied to three instances of limited rationality, widely discussed in cognitive psychology: Stereotypical Thinking, the Framing Effect, and the Anchoring Effect. (shrink)

In this paper we design a new logical system to explicitly model the different deductive reasoning steps of a boundedly rational agent. We present an adequate system in line with experimental findings about an agent’s reasoning limitations and the cognitive effort that is involved. Inspired by Dynamic Epistemic Logic, we work with dynamic operators denoting explicit applications of inference rules in our logical language. Our models are supplemented by (a) impossible worlds (not closed under logical consequence), suitably structured according to (...) the effect of inference rules, and (b) quantitative components capturing the agent’s cognitive capacity and the cognitive costs of rules with respect to certain resources (e.g. memory, time). These ingredients allow us to avoid problematic logical closure principles, while at the same time deductive reasoning is reflected in our dynamic truth clauses. We further show that our models can be reduced to awareness-like plausibility structures that validate the same formulas and we give a sound and complete axiomatization with respect to them. This approach to the agent’s internal deductive reasoning is finally combined with actions of external information. (shrink)

Philosophers often state that the persistence of objects in vision is experienced differently than the persistence of sounds in audition. This difference is expressed by using metaphors from the metaphysical endurantism/perdurantism debate. For instance, it is claimed that only sounds are perceived as “temporally extended”. The paper investigates whether it is justified to characterize visually experienced objects and auditorily experienced sounds as different types of entities: endurants and perdurants respectively. This issue is analyzed from the perspective of major specifications of (...) the endurance/perdurance distinction connected, inter alia, with the notions of temporal parts and temporal localization. It is argued that it is unjustified to characterize visually experienced objects and auditorily experienced sounds as different types of entities in respect of how they persist. On the other hand, the apparent difference in the way of persisting can be explained by the presence of contingent differences between typical visual and auditory experiences. (shrink)

While there is a growing philosophical interest in analysing olfactory experiences, the mereological structure of odours considered in respect of how they are perceptually experienced has not yet been extensively investigated. The paper argues that odours are perceptually experienced as having a mereological structure, but this structure is significantly different from the spatial mereological structure of visually experienced objects. Most importantly, in the case of the olfactory part-structure, the classical weak supplementation principle is not satisfied. This thesis is justified by (...) referring to empirical results in olfactory science concerning the human ability to identify components in complex olfactory stimuli. Further, it is shown how differences between olfactory and visual mereologies may arise from the way in which these modalities represent space. (shrink)

According to a common opinion, human olfactory experiences are significantly different from human visual experiences. For instance, olfaction seems to have only rudimentary abilities to represent space; it is not clear whether olfactory experiences have any mereological structure; and while vision presents the world in terms of objects, it is a matter of debate whether there are olfactory object-representations. This paper argues that despite these differences visual and olfactory experiences share a hierarchical subject/property structure. Within this structure, olfactorily experienced odours (...) and visual objects have the same status: they are primary subjects which unify other represented elements into perceptual units. (shrink)

Neural Darwinism (ND) is a large scale selectionist theory of brain development and function that has been hypothesized to relate to consciousness. According to ND, consciousness is entailed by reentrant interactions among neuronal populations in the thalamocortical system (the ‘dynamic core’). These interactions, which permit high-order discriminations among possible core states, confer selective advantages on organisms possessing them by linking current perceptual events to a past history of value-dependent learning. Here, we assess the consistency of ND with 16 widely recognized (...) properties of consciousness, both physiological (for example, consciousness is associated with widespread, relatively fast, low amplitude interactions in the thalamocortical system), and phenomenal (for example, consciousness involves the existence of a private flow of events available only to the experiencing subject). While no theory accounts fully for all of these properties at present, we find that ND and its recent extensions fare well. (shrink)

The standard behavioral index for human consciousness is the ability to report events with accuracy. While this method is routinely used for scientific and medical applications in humans, it is not easy to generalize to other species. Brain evidence may lend itself more easily to comparative testing. Human consciousness involves widespread, relatively fast low-amplitude interactions in the thalamocortical core of the brain, driven by current tasks and conditions. These features have also been found in other mammals, which suggests that consciousness (...) is a major biological adaptation in mammals. We suggest more than a dozen additional properties of human consciousness that may be used to test comparative predictions. Such homologies are necessarily more remote in non-mammals, which do not share the thalamocortical complex. However, as we learn more we may be able to make “deeper” predictions that apply to some birds, reptiles, large-brained invertebrates, and perhaps other species. (shrink)

Why can’t we keep as many items as we want in working memory? It has long been debated whether this resource limitation is a bug or instead a feature. We propose that the resource limitation is a consequence of a useful feature. Specifically, we propose that flexible cognition requires time-based binding, and time-based binding necessarily limits the number of memoranda that can be stored simultaneously. Time-based binding is most naturally instantiated via neural oscillations, for which there exists ample experimental evidence. (...) We report simulations that illustrate this theory and that relate it to empirical data. We also compare the theory to several other resource theories. (shrink)

Cognitive Science, Volume 46, Issue 4, April 2022.

A number of recent studies have revealed correspondences between song- and language-related neural structures, pathways, and gene expression in humans and songbirds. Analyses of vocal learning, song structure, and the distribution of song elements have similarly revealed a remarkable number of shared characteristics with human speech. This article reviews recent developments in the understanding of these issues with reference to the phonological phenomena observed in human language. This investigation suggests that birds possess a host of abilities necessary for human phonological (...) computation, as evidenced by behavioral, neuroanatomical, and molecular genetic studies. Vocal-learning birds therefore present an excellent model for studying some areas of human phonology, though differences in the primitives of song and language as well as the absence of a human-like morphosyntax make human phonology differ from birdsong phonology in crucial ways. (shrink)

Making recognition decisions often requires us to reference the contents of working memory, the information available for ongoing cognitive processing. As such, understanding how recognition decisions are made when based on the contents of working memory is of critical importance. In this work we examine whether recognition decisions based on the contents of visual working memory follow a continuous decision process of graded information about the correct choice or a discrete decision process reflecting only knowing and guessing. We find a (...) clear pattern in favor of a continuous latent strength model of visual working memory–based decision making, supporting the notion that visual recognition decision processes are impacted by the degree of matching between the contents of working memory and the choices given. Relation to relevant findings and the implications for human information processing more generally are discussed. (shrink)