Depression, attention, and time estimation

Depression is known to affect several cognitive functions, but little is known about the effect of this neuropsychological disorder on timing tasks. In the present experiment, 15 depressed and 20 non-depressed participants, classified on the basis of the Beck Depression Inventory, were tested on attentional and on temporal processing tasks. On the Continuous Performance Test, depressed participants made more omissions, but not more erroneous responses, than non-depressed participants. As well, discrimination of relatively long intervals (1120 vs 1280 ms) was poorer for the depressed group, which was not the case for discrimination of brief durations (80 vs 120 ms, and 450 vs 550 ms). Finally, there was a significant difference between groups regarding the variability of 1- or 10-s interval productions made with continuous series of finger taps. The attentional requirements of long-interval processing seems to be a critical factor in depression-induced deficits of temporal processing.     

A neural theory of visual attention: bridging cognition and neurophysiology

A neural theory of visual attention (NTVA) is presented. NTVA is a neural interpretation of C. Bundesen's (1990) theory of visual attention (TVA). In NTVA, visual processing capacity is distributed across stimuli by dynamic remapping of receptive fields of cortical cells such that more processing resources (cells) are devoted to behaviorally important objects than to less important ones. By use of the same basic equations used in TVA, NTVA accounts for a wide range of known attentional effects in human performance (reaction times and error rates) and a wide range of effects observed in firing rates of single cells in the primate visual system. NTVA provides a mathematical framework to unify the 2 fields of research--formulas bridging cognition and neurophysiology.     

Threaded cognition: an integrated theory of concurrent multitasking

The authors propose the idea of threaded cognition, an integrated theory of concurrent multitasking--that is, performing 2 or more tasks at once. Threaded cognition posits that streams of thought can be represented as threads of processing coordinated by a serial procedural resource and executed across other available resources (e.g., perceptual and motor resources). The theory specifies a parsimonious mechanism that allows for concurrent execution, resource acquisition, and resolution of resource conflicts, without the need for specialized executive processes. By instantiating this mechanism as a computational model, threaded cognition provides explicit predictions of how multitasking behavior can result in interference, or lack thereof, for a given set of tasks. The authors illustrate the theory in model simulations of several representative domains ranging from simple laboratory tasks such as dual-choice tasks to complex real-world domains such as driving and driver distraction.     

An integrated model of feedback-seeking behavior: disposition, context, and cognition

This study replicates, integrates, and extends prior research on the dispositional, contextual, and cognitive antecedents of feedback-seeking behavior. Regression analysis was used to analyze data collected from a sample of salespeople (N = 310) from 2 Fortune 500 companies. The study hypotheses were supported with the following results. First, the individual disposition of learning goal orientation and the contextual factors of leader consideration and leader initiation of structure influenced cognitions about the perceived cost and value of feedback seeking. Second, the strength of the relationship of learning goal orientation with the cost and value perceptions was moderated by the leadership style of the supervisor.     

Massed and spaced learning in honeybees: the role of CS, US, the intertrial interval, and the test interval

Conditioning the proboscis extension reflex of harnessed honeybees (Apis mellifera) is used to study the effect temporal spacing between successive conditioning trials has on memory. Retention is monitored at two long-term intervals corresponding to early (1 and 2 d after conditioning) and late long-term memory (3 and 4 d). The acquisition level is varied by using different conditioned stimuli (odors, mechanical stimulation, and temperature increase at the antenna), varying strengths of the unconditioned stimulus (sucrose), and various numbers of conditioning trials. How learning trials are spaced is the dominant factor both for acquisition and retention, and although longer intertrial intervals lead to better acquisition and higher retention, the level of acquisition per se does not determine the spacing effect on retention. Rather, spaced conditioning leads to higher memory consolidation both during acquisition and later, between the early and long-term memory phases. These consolidation processes can be selectively inhibited by blocking protein synthesis during acquisition.     

Gaze cueing of attention: visual attention, social cognition, and individual differences

During social interactions, people's eyes convey a wealth of information about their direction of attention and their emotional and mental states. This review aims to provide a comprehensive overview of past and current research into the perception of gaze behavior and its effect on the observer. This encompasses the perception of gaze direction and its influence on perception of the other person, as well as gaze-following behavior such as joint attention, in infant, adult, and clinical populations. Particular focus is given to the gaze-cueing paradigm that has been used to investigate the mechanisms of joint attention. The contribution of this paradigm has been significant and will likely continue to advance knowledge across diverse fields within psychology and neuroscience.     

Conditioning,attention, and the CS-US interval

A revised version of the Rescorla-Wagner (1972) mathematical model is presented. A metatheoretical assumption of an attentional process, the added revision, is conceived as an independent α-salience growth factor determining both rate of association and performance. Conditioned stimulus-unconditioned stimulus (CS-US) correlation, and CS-US interval (two primary conditioning parameters) are incorporated in the mathematical model as α-salience growth rate and as α-salience and association asymptote factors, respectively. In this manner, the long-standing issue of necessary and sufficient factors in classical conditioning is resolved. An empirical assessment of the model’s parameters has been included.     

Age-related differences in time-based prospective memory: The role of time estimation in the clock monitoring strategy

Time-based prospective memory (TBPM) is required when it is necessary to remember to perform an action at a specific future point in time. This type of memory has been found to be particularly sensitive to ageing, probably because it requires a self-initiated response at a specific time. In this study, we sought to examine the involvement of temporal processes in the time monitoring strategy, which has been demonstrated to be a decisive factor in TBPM efficiency. We compared the performance of young and older adults in a TBPM task in which they had to press a response button every minute while categorising words. The design allowed participants to monitor time by checking a clock whenever they decided. Participants also completed a classic time-production task and several executive tasks assessing inhibition, updating and shifting processes. Our results confirm an age-related lack of accuracy in prospective memory performance, which seems to be related to a deficient strategic use of time monitoring. This could in turn be partially explained by age-related temporal deficits, as evidenced in the duration production task. These findings suggest that studies designed to investigate the age effect in TBPM tasks should consider the contribution of temporal mechanisms.     

An integrated theory of the mind

Adaptive control of thought-rational (ACT-R; J. R. Anderson & C. Lebiere, 1998) has evolved into a theory that consists of multiple modules but also explains how these modules are integrated to produce coherent cognition. The perceptual-motor modules, the goal module, and the declarative memory module are presented as examples of specialized systems in ACT-R. These modules are associated with distinct cortical regions. These modules place chunks in buffers where they can be detected by a production system that responds to patterns of information in the buffers. At any point in time, a single production rule is selected to respond to the current pattern. Subsymbolic processes serve to guide the selection of rules to fire as well as the internal operations of some modules. Much of learning involves tuning of these subsymbolic processes. A number of simple and complex empirical examples are described to illustrate how these modules function singly and in concert.     

Basic response time tools for studying general processing capacity in attention, perception, and cognition

One of the more important constructs in the study of attention, perception, and cognition is that of capacity. The authors reviewed some of the common meanings of this construct and proposed a more precise treatment. They showed how the distribution of response times can be used to derive measures of process capacity and to further illustrate how these measures can be used to address important hypotheses in cognition.     

An instance theory of attention and memory

An instance theory of attention and memory (ITAM) is presented that integrates formal theories of attention and memory phenomena by exploiting commonalities in their formal structure. The core idea in each theory is that performance depends on a choice process that can be modeled as a race between competing alternatives. Attention and categorization are viewed as different perspectives on the same race. Attention selects objects by categorizing them; objects are categorized by attending to them. ITAM incorporates each of its ancestors as a special case, so it inherits their successes.     

Translating cognition into action: the role of visual guidance in observational learning

This experiment examined the role of two forms of visual guidance in facilitating the translation of cognitive representations into action. Subjects matched a modeled action pattern either concurrently with the model or after the modeled display. They then either did or did not visually monitor their actions during tests of production accuracy in the model's absence. Acquisition of the cognitive representation was assessed periodically. Concurrent matching of modeled actions or visual monitoring of productions both increased the level of observational learning. The more accurate the cognitive representation, the more skilled were subsequent reproductions of the modeled actions. After acquiring proficiency in converting cognition to action, subjects maintained their level of performance accuracy even though modeled and visual-monitoring guidance were withdrawn. These results are in accordance with the theory that cognitive representation mediates response production and that corrective adjustments through visual guidance aid in the translation of conception into action.     

Auditory objects of attention: the role of interaural time differences.

The role of interaural time difference (ITD) in perceptual grouping and selective attention was explored in 3 experiments. Experiment 1 showed that listeners can use small differences in ITD between 2 sentences to say which of 2 short, constant target words was part of the attended sentence, in the absence of talker or fundamental frequency differences. Experiments 2 and 3 showed that listeners do not explicitly track components that share a common ITD. Their inability to segregate a harmonic from a target vowel by a difference in ITD was not substantially changed by the vowel being placed in a sentence context, where the sentence shared the same ITD as the rest of the vowel. The results indicate that in following a particular auditory sound source over time, listeners attend to perceived auditory objects at particular azimuthal positions rather than attend explicitly to those frequency components that share a common ITD.     

Genes, cognition and dyslexia: learning to read the genome

Studies of dyslexia provide vital insights into the cognitive architecture underpinning both disordered and normal reading. It is well established that inherited factors contribute to dyslexia susceptibility, but only very recently has evidence emerged to implicate specific candidate genes. In this article, we provide an accessible overview of four prominent examples--DYX1C1, KIAA0319, DCDC2 and ROBO1--and discuss their relevance for cognition. In each case correlations have been found between genetic variation and reading impairments, but precise risk variants remain elusive. Although none of these genes is specific to reading-related neuronal circuits, or even to the human brain, they have intriguing roles in neuronal migration or connectivity. Dissection of cognitive mechanisms that subserve reading will ultimately depend on an integrated approach, uniting data from genetic investigations, behavioural studies and neuroimaging.