Context-specific adjustment of cognitive control: Transfer of adaptive control sets

Cognitive control protects processing of relevant information from interference by irrelevant information. The level of this processing selectivity can be flexibly adjusted to different control demands (e.g., frequency of conflict) associated with a certain context, leading to the formation of specific context–control associations. In the present study we investigated the robustness and transferability of the acquired context–control demands to new situations. In three experiments, we used a version of the context-specific proportion congruence (CSPC) paradigm, in which each context (e.g., location) is associated with a specific conflict frequency, determining high and low control demands. In a learning phase, associations between context and control demands were established. In a subsequent transfer block, stimulus–response mappings, whole task sets, or context–control demands changed. Results showed an impressive robustness of context–control associations, as context-specific adjustments of control from the learning phase were virtually unaffected by new stimuli and tasks in the transfer block. Only a change of the context–control demand eliminated the context-specific adjustment of control. These findings suggest that context–control associations that have proven to be adaptive in the past are continuously applied despite major changes in the task structure as long as the context–control associations remain the same.     

Context-specific attentional sampling: Intentional control as a pre-requisite for contextual control

Recent work suggests that environmental cues associated with previous attentional control settings can rapidly and involuntarily adjust attentional priorities. The current study tests predictions from adaptive-learning and memory-based theories of contextual control about the role of intentions for setting attentional priorities. To extend the empirical boundaries of contextual control phenomena, and to determine whether theoretical principles of contextual control are generalizable we used a novel bi-dimensional stimulus sampling task. Subjects viewed briefly presented arrays of letters and colors presented above or below fixation, and identified specific stimuli according to a dimensional (letter or color) and positional cue. Location was predictive of the cued dimension, but not the position or identity. In contrast to previous findings, contextual control failed to develop through automatic, adaptive-learning processes. Instead, previous experience with intentionally changing attentional sampling priorities between different contexts was required for contextual control to develop.     

On the development of stimulus control

Pigeons were trained to peck one key when presented with white noise at any of five intensities lower than a reference intensity, and to peck another key when presented with white noise at any of five intensities greater than the reference intensity. The shape of the stimulus control curves (proportion of responses to one key versus stimulus intensity) changed from a horizontal line at the beginning of training to the sigmoid form of typical psychometric functions at the end of training. The development of stimulus control is described in terms of a model based on the theory of signal recognition and a concept of attention.     

Comparing the effects of conscious monitoring and conscious control on motor performance

We compared the effects of conscious monitoring and control on motor performance. Participants were instructed to adopt an internal or external focus of attention in different blocks of a darts task. For one group, the internal as well as external focus instructions emphasized monitoring. For another group, the instructions emphasized control in the two focus conditions. Furthermore, participants’ propensity for monitoring and control was gauged via two factors of the Movement Specific Reinvestment Scale (MSRS) (Masters, Eves, & Maxwell, 2005). These factors were Movement Self-Consciousness (MS-C) and Conscious Motor Processing (CMP), which measure propensity for conscious monitoring and control, respectively. Performance differences between the internal and external focus blocks were expressed as mean radial error (MRE). Results revealed a 3-way interaction between CMP, instruction type (monitoring versus control) and an order effect. Only in the conscious control-group, but not the conscious monitoring-group was there a 2-way interaction between CMP and order. In the conscious control-group, participants with high CMP scores showed worse performance in whichever focus block (internal or external) was presented last. There were no significant effects in the monitoring-group or of MS-C. These findings indicate that conscious control has a stronger effect on motor performance than conscious monitoring.     

Context-specific control in the single-prime negative-priming procedure

The current paper examines the applicability of the context-specific control principle to the probe selection dependence of negative-priming effects using the single-prime procedure. In a series of experiments, we highlight the applicability of the context-specific control principle, first by illustrating a key result that implicates the role of context-specific control and challenges the contextual similarity principle. Following this, we show the importance of distinct probe contexts in the single-prime negative-priming procedure and report a novel finding that illustrates a learning effect that can occur within an experimental session. Finally, we test the relation of our novel learning effect to a related learning proposal offered by Frings and Wentura (2006), and we demonstrate that the learning involved in context-specific control is not dependent on contingency learning. Overall, the patterns of results highlight the role of context-sensitive memory in controlling how current perception and action are integrated with prior experience.     

Context-specific control in the single-prime negative-priming procedure

The current paper examines the applicability of the context-specific control principle to the probe selection dependence of negative-priming effects using the single-prime procedure. In a series of experiments, we highlight the applicability of the context-specific control principle, first by illustrating a key result that implicates the role of context-specific control and challenges the contextual similarity principle. Following this, we show the importance of distinct probe contexts in the single-prime negative-priming procedure and report a novel finding that illustrates a learning effect that can occur within an experimental session. Finally, we test the relation of our novel learning effect to a related learning proposal offered by Frings and Wentura (2006), and we demonstrate that the learning involved in context-specific control is not dependent on contingency learning. Overall, the patterns of results highlight the role of context-sensitive memory in controlling how current perception and action are integrated with prior experience.     

The Stroop effect at 80: The competition between stimulus control and cognitive control

For more than 80 years, researchers have examined the interference between automatic processing of stimuli, such as the meaning of color words, on performance of a controlled‐processing task such as naming the color in which words are printed. The Stroop effect and its many variations provide an ideal test platform for examining the competition between stimulus control and cognitive control of attention, as reflected in behavior. The two experiments reported here show that rhesus monkeys, like human adults, show interference from incongruous stimulus conditions in a number‐Stroop task, and that the monkeys may be particularly susceptible to influence from response strength and less able, relative to human adults, of using executive attention to minimize this interference.     

Behavioral control by an imprinted stimulus: long-term effects

Newly hatched ducklings were exposed to imprinting procedures and subsequently trained to peck a key by presenting the imprinting stimulus as the reinforcing (response-contingent) event. Individual ducklings then lived in the apparatus under an arrangement in which each peck produced a 15-sec stimulus presentation. For all ducklings, key-pecks tended to occur in bursts, and as the duckling matured, burst length decreased and the interval between bursts increased. However, even when subjects were 60 days old, some responses still occurred.     

On the role of object representations in substitution masking

Three experiments were conducted to investigate the role of object representations in object substitution masking (OSM). OSM occurs when a very sparse mask is presented simultaneously with a target stimulus and the target offsets first, leaving the mask to linger in the display for some time. Results confirm earlier claims that there is an isolatable object-level component to OSM and indicate that a target can be protected from OSM if, prior to offsetting, it can be represented as a distinct object from the mask. When the mask was presented as sliding past the target (Experiment 1), as jiggling independently of the target (Experiment 2), or in a different color from the target (Experiment 3), OSM was reduced or eliminated. This suggests that OSM reflects basic updating processes that allow the perception of continuity of object identity over change.     

Real-time generation of representations for cognitive models

Computerized models of human cognition and behavior have been used to help researchers refine their theories of cognitive processes. Two difficulties inherent in using these cognitive models are that building representations of to-be-modeled groups or individuals is (1) time-consuming and (2) prone to error when performed manually. The use of computerized tools to build representations for cognitive models could alleviate these problems. Such a set of tools has been developed and applied to the task of modeling individual aviation pilots performing flight maneuvers in real time. A study conducted with 27 pilots confirms the accuracy of the computer-generated representations.     

Implicit body representations and the conscious body image

Recent studies have revealed that somatosensory processing relies on a class of implicit body representations showing large distortions of size and shape. The relation between these representations and the conscious body image remains unclear. Dissociations have been reported in the clinical literature on eating disorders between different body image measures, with larger and more consistent distortions found with depictive measures, in which participants compare their body to a visual depiction of a body, than metric measures, in which participants compare their body to some non-body standard. Here, we compared implicit body representations underlying position sense to the body image measured with both depictive and metric methods. The body image was measured using both a depictive method (template matching) in which participants judged whether their hand was wider or more slender than a shown hand picture, and a metric method (line length) in which participants judged whether different parts of their hand were shorter or longer than a presented line. Consistent with previous findings, characteristic distortions were found for the implicit body representation underlying position sense. These distortions were also found in attenuated form for metric - but not depictive - body image measures. While replicating the basic dissociation between implicit body representations and the conscious body image, these results demonstrate that this dissociation is not absolute and specific tasks may utilise both to varying degrees depending on task demands. Metric measures may not be pure measures of body image, but some combination of visual and somatosensory body representations.     

Object-substitution masking degrades the quality of conscious object representations

Object-substitution masking (OSM) is a unique paradigm for the examination of object updating processes. However, existing models of OSM are underspecified with respect to the impact of object updating on the quality of target representations. Using two paradigms of OSM combined with a mixture model analysis we examine the impact of post-perceptual processes on a target’s representational quality within conscious awareness. We conclude that object updating processes responsible for OSM cause degradation in the precision of object representations. These findings contribute to a growing body of research advocating for the application of mixture model analysis to the study of how cognitive processes impact the quality (i.e., precision) of object representations.     

Associative activation of stimulus representations restores lost salience: implications for perceptual learning

In 3 experiments, rats received preexposure to presentations of a compound flavor BX. The effective salience of B was then tested by assessing its ability to interfere with the aversion controlled by another flavor or the tendency to drink a saline solution after the induction of a salt need. It was found that the effective salience of B was maintained when during preexposure, presentations of BX alternated with presentations of X alone. This was true both when BX was presented as a simultaneous compound (Experiment 1) and as a serial compound (X-->B; Experiments 2 and 3); salience was not maintained when the serial compound took the form B-->X (Experiments 2 and 3a). It was argued that the salience of B declines during preexposure but is restored when presentations of X are able to activate the representation of B by way of the associative X-B link.     

Discriminative stimulus control and the effects of concurrent operants.

Discriminative-stimulus-control functions were investigated in a concurrent operant context. Variable-interval reinforcement schedules were arranged for pigeons on two response keys. One key, illuminated with a white vertical line on green background (position irrelevant), was programmed with a given schedule value across groups. For different groups of pigeons, the alternative key, illuminated with green alone, was programmed with twice, the same, or half the reinforcement frequency of the other key. Stimulus-control gradients were collected from both keys as line orientation was varied. On the green-plus-line alternative, flattest gradients were observed when twice the reinforcement frequency was concurrently programmed and the steepest were observed when equal values were concurrently programmed. Also examined were the effects of a programmed changeover delay, important in maintaining the independence of concurrent operants. The changeover delay was found to have relatively minor effects upon stimulus control, despite its typical and marked effects upon steady-state responding.     

Redundancy gains and costs in cognitive processing: effects of short stimulus onset asynchronies

In 7 experiments, the influence of varying stimulus onset asynchronies (SOAs) on the processing of redundant information about words and pseudowords was investigated. All stimuli were visually presented once or twice with 2 copies of the same item flashed either simultaneously or with short SOAs between presentations. The experiments revealed a redundancy gain for words that was absent for pseudowords. Furthermore, the redundancy gain disappeared at an SOA of 50 ms, and there was a gradual performance decline at longer SOAs. However, probing SOAs of 150 and 300 ms revealed that, compared with presentation of 1 target stimulus alone, words were processed significantly faster when target and redundantcopy appeared with a 150-ms lag. The results are tentatively explained in a neurocognitive framework.     

Comparison of stimulus control and reinforcement control effects on imitative behavior

An attempt was made to evaluate reinforcement and stimulus control of imitative and non-imitative behavior. The imitative response required the subject to duplicate the experimenter's response by matching blocks that varied in color. The factor designed to evaluate stimulus control was fading, a procedure that systematically varies the differences between the imitative and non-imitative stimuli. The topography and duration of the non-imitative stimuli were faded in. The factors designed to evaluate reinforcement control were differential reinforcement of non-imitative behavior and time out from positive reinforcement. The results showed stimulus control of non-imitation to be more important than reinforcement control, and that reinforcing events were not sufficient to control non-imitation; while the arrangement of stimulus events was sufficient to control non-imitation. These results were related to studies providing evidence for the processes of discrimination and generalization.     

Target duration effects on iconic memory: the confounding role of changing stimulus dimensions

Observers' accuracy in detecting a narrow spatial gap between two brief, luminous rectangles presented successively was determined within a two-alternative, forced-choice procedure. This successive-field task requires iconic memory, because the information (rectangle position) in the two presentations must be combined for successful gap detection. On this task, the effect of varying the duration of the first rectangle was systematically investigated over several target luminance levels and for several ISI conditions between rectangles. At the long ISI conditions (100 and 300 ms), the effects of increasing stimulus duration was to improve performance. However, at the brief ISI condition (20 ms), increasing stimulus duration initially depressed task performance. It was found that, with practice, this initial performance drop largely disappeared, and the beneficial influence of increasing target duration was again obtained. These results are discussed in terms of (a) a proposed retinal locus for the iconic memory involved and (b), at a more general level, the potentially distracting role of changing stimulus dimensions on a task employing transient stimuli as in the present study.