Miller (1956) summarized evidence that people can remember about seven chunks in short-term memory (STM) tasks. However, that number was meant more as a rough estimate and a rhetorical device than as a real capacity limit. Others have since suggested that there is a more precise capacity limit, but that it is only three to five chunks. The present target article brings together a wide variety of data on capacity limits suggesting that the smaller capacity limit is real. Capacity limits (...) will be useful in analyses of information processing only if the boundary conditions for observing them can be carefully described. Four basic conditions in which chunks can be identified and capacity limits can accordingly be observed are: (1) when information overload limits chunks to individual stimulus items, (2) when other steps are taken specifically to block the recoding of stimulus items into larger chunks, (3) in performance discontinuities caused by the capacity limit, and (4) in various indirect effects of the capacity limit. Under these conditions, rehearsal and long-term memory cannot be used to combine stimulus items into chunks of an unknown size; nor can storage mechanisms that are not capacity-limited, such as sensory memory, allow the capacity-limited storage mechanism to be refilled during recall. A single, central capacity limit averaging about four chunks is implicated along with other, noncapacity-limited sources. The pure STM capacity limit expressed in chunks is distinguished from compound STM limits obtained when the number of separately held chunks is unclear. Reasons why pure capacity estimates fall within a narrow range are discussed and a capacity limit for the focus of attention is proposed. Key Words: attention; enumeration; information chunks; memory capacity; processing capacity; processing channels; serial recall; short-term memory; storage capacity; verbal recall; working memory capacity. (shrink)

Highlights of a difficult history -- The preliminary identification of our topic -- Approaches -- Bradley's protest -- James's disjunctive theory -- The source of Bradley's dissatisfaction -- Behaviourism and after -- Heirs of Bradley in the twentieth century -- The underlying metaphysical issue -- Explanatory tactics -- The basic distinction -- Metaphysical categories and taxonomies -- Adverbialism, multiple realizability, and natural kinds -- Adverbialism and levels of explanation -- Taxonomies and supervenience relations -- Rejecting the process : first view (...) -- Supervenience-failure -- The modal commitments of the process : first view -- The interference argument : a putative problem for adverbialist accounts -- Cognitive unison -- The problem with attitude based adverbialism -- Gilbert Ryle and Alan White -- White's argument against disposition-based adverbialism -- The cognitive unison theory -- Tasks -- Cognitive processes -- Potential service of a task -- Superordinate tasks -- Some features of the theory -- Divided attention -- Degrees of attention and merely partial attention -- The causal life of attention -- Mental causation -- How to respond to mental causation objections -- The causal role of attention -- Attention as an enabling condition -- Counterfactuals -- The causal relevance of attention per se -- Counterfactuals and causally relevant properties -- Objections to counterfactual analysis of causation and of causal relevance -- The extrinsicness of unison -- The privative character of unison and the problem of absence causation -- Causal exclusion -- Consequences for cognitive psychology -- Psychology and metaphysics -- The metaphysical commitments of the process-identifying project -- The diverse explanatory construals of current psychological results -- Reasons for deflation -- Inductively unreliable properties -- Questions without answers -- The positive payoff -- Philosophical work for the theory of attention -- Putting attention to philosophical work -- Attention and reference -- Attention and consciousness -- Prospects for optimism. (shrink)

The nature of attention has been the topic of a lively research programme in psychology for over a century. But there is widespread agreement that none of the theories on offer manage to fully capture the nature of attention. Recently, philosophers have become interested in the debate again after a prolonged period of neglect. This paper contributes to the project of explaining the nature of attention. It starts off by critically examining Christopher Mole’s prominent “adverbial” account of attention, which traces (...) the failure of extant psychological theories to their assumption that attending is a kind of process. It then defends an alternative, process-based view of the metaphysics of attention, on which attention is understood as an activity and not, as psychologists seem to implicitly assume, an accomplishment. The entrenched distinction between accomplishments and activities is shown to shed new light on the metaphysics of attention. It also provides a novel diagnosis of the empirical state of play. (shrink)

A central thesis of this book on the cognitive neuroscience of attention is that attention is not a single entity, but a finite set of brain processes that ...

When performing a skilled action—whether something impressive like a double somersault or something mundane like reaching for a glass of water—you exercise control over your bodily movements. Specifically, you guide their course. In what does that control consist? In this dissertation, I argue that it consists in attending to what you are doing. More specifically, in attending, agents harness their perceptual and perceptuomotor states directly and practically in service of their goals and, in doing so, settle the fine-grained manner in (...) which their bodies will move—details an intention alone leaves unsettled. This requires, among other things, that we reject views on which agents’ control is identical with their practical rationality. When all goes well, agents attentionally prioritize what is motivationally relevant to them to the exclusion of what would otherwise distract them from achieving their goals. However, sometimes agents attend distractedly—i.e., without prioritizing. As the aim of attention is to avoid distraction, this entails the possibility of defective attention. Defective attention, in turn, casts light on scenarios in which agents lose control over what they are doing, as when a skilled practitioner ‘chokes under pressure’. A complaint sometimes levelled against accounts, like mine, that claim to reduce agents’ control of their behaviour to that of causally efficacious mental states or events is that these accounts invariably deprive agents themselves of their rightful role in the generation of behaviour. This is the “Disappearing Agent Problem” for “reductive” or “event-causal” theories of action. I argue that, correctly understood, extant reductive theories do face a genuine Disappearing Agent Problem. However, it is a problem we solve by recognizing the role that conscious attention plays in making an action the agent’s own. Accordingly, I develop and defend an attentional account of action ownership. On this view, allocating conscious attention in service of your goals is sufficient for a kind of conscious perspective (“motivational perspective”), which, when active in controlling your behaviour, constitutes the behaviour as your own doing. As I explain, such perspective also contributes to explaining the subjective structure of your perceptual awareness of the world around you. (shrink)

From the conception of Baddeley’s visuospatial sketchpad, visual working memory and visual attention have been closely linked concepts. An attractive model has advocated unity of the two cognitive functions, with attention serving the active maintenance of sensory representations. However, empirical evidence from various paradigms and dependent measures has now firmly established an at least partial dissociation between visual attention and visual working memory maintenance e thus leaving unclear what the relationship between the two concepts is. Moreover, a focus on sensory (...) storage has treated visual working memory as a reflection of the past, with attention as a limiting resource. This view ignores what storage is for: immediate or future action. We argue that rather than serving sensory storage, attention emerges from coupling relevant sensory and action representations within working memory. Importantly, this coupling is bidirectional: First, through recurrent feedback mechanisms, action coupling results in the enhancement of the appropriate sensory memory representation. Under this view, unattended memories are currently not coupled to an action plan, but are not necessarily lost and remain available for future tasks when necessary. Second, through the very same feedback projections, attention serves as the credit assignment mechanism for the action’s outcome. When the action is successful, the associated representations are being reinforced, leading to more robust consolidation and more rapid retrieval in the future e thus explaining performance benefits for attended memories without assuming that attention serves as the maintenance mechanism. By firmly grounding VWM in the action system, the new framework integrates a range of behavioural and neurophysiological findings and avoids circularity in explaining the role of attention in working memory. (shrink)

Evidence concerning the relationship between attention and multisensory integration has long been thought to lead us into a paradox. The paradox has its roots in evidence that seems to show that attention exerts an influence on integration, and that integration also exerts an influence on attention. This creates an appearance of paradox only if it is understood to imply that particular instances of the integration process must occur both before and after particular instances of the attention process. But this appearance (...) of paradox can be removed if we can find a way to resist the idea that there must be fixed temporal relations between the instances of these processes. That idea can seem hard to resist if both are understood to be processes of the sort that are brought to a halt by their own completion. Reflection on a metaphysical distinction between different sorts of process shows this understanding can be rejected. The appearance of paradox is thereby removed. (shrink)