Individual stopping times and cognitive control: Converging evidence for the stop signal task from a continuous tracking paradigm

The present study introduces a continuous tracking procedure to investigate cognitive stopping in individual trials. Our measure of stopping performance had a mean similar to mean stopping times estimated in the stop signal paradigm, suggesting a common underlying process. Additional findings indicate that stopping performance and tracking performance were dissociable. First, while stopping times were primarily affected by stop signal modality, tracking performance was primarily affected by tracking difficulty. Second, tracking performance influenced tracking but not stopping in immediately following trials. Stopping influenced neither tracking performance nor stopping in immediately following trials. Finally, there was no correlation between tracking performance and stopping performance, or any dependency between them as found in the conditional means.     

Living on the edge: strategic and instructed slowing in the stop signal task

The stop signal task is widely adopted to assess motor inhibition performance in both clinical and non-clinical populations. Several recent studies explored the influence of strategic approaches to the task. In particular, response slowing seems to be a strategic approach commonly adopted to perform the task. In the present study, we compared a standard version with a strategic version of the task, in which participants were explicitly instructed to slow down responses. Results showed that the instructed slowing did not affect the main inhibition measure, thus confirming the robustness of the stop signal index. On the other hand, it apparently changed the nature of the task, as shown by the lack of correlation between the standard and the strategic versions. In addition, we found a specific influence of individual characteristics on slowing strategies. In the standard version, adherence to task instructions was positively correlated with compliant traits of personality. Despite instructions to maximize response speed, non-compliant participants preferred to adopt a slowing strategy in the standard version of the task, up to a speed level similar to the strategic version, where slowing was required by task instructions. Understanding the role of individual approach to the task seems to be crucial to properly identify how participants cope with task instructions.     

The interaction between stop signal inhibition and distractor interference in the flanker and Stroop task

In the present study, two experiments were conducted to investigate the interaction between the behavioral inhibition, measured by the stop signal task, and distractor interference, measured by the flanker task and the Stroop task. In the first experiment, the stop signal task was combined with a flanker task. Analysis revealed that participants responded faster when the distractors were congruent to the target. Also, the data suggest that it is more difficult to suppress a reaction when the distractors were incongruent. Whether the incongruent distractor was part of the response set (i.e. the distractor could also be a target) or not, had no influence on stopping reactions. In the second experiment, the stop signal task was combined with a manual version of the Stroop task and the degree of compatibility was varied. Even though in the second experiment of the present study interference control is differently operationalized, similar results as in the first experiment were found, indicating that inhibition of motor responses is influenced by the presentation of distracting information that is not part of the response set.     

The effect of interference in the early processing stages on response inhibition in the stop signal task

In the present study, the relation between interference at the early processing stages and response inhibition was investigated. In previous studies, response stopping appeared to be slowed down when irrelevant distracting information was presented. The purpose of the present study was to further explore the relationship between interference control and response inhibition. In Experiment 1, a stop signal paradigm was combined with a global/local task. The typical global-to-local interference effect is generally attributed to early processing stages, such as stimulus perception and identification. Results of this experiment demonstrated a congruency effect for both reaction time data and zstopping performance. In Experiment 2, these results were replicated with a flanker task that used stimulus-incongruent but response-congruent flankers. Results of both experiments suggest that response inhibition and interference at the early processing stages interact.     

The effect of interference in the early processing stages on response inhibition in the stop signal task

In the present study, the relation between interference at the early processing stages and response inhibition was investigated. In previous studies, response stopping appeared to be slowed down when irrelevant distracting information was presented. The purpose of the present study was to further explore the relationship between interference control and response inhibition. In Experiment 1, a stop signal paradigm was combined with a global/local task. The typical global-to-local interference effect is generally attributed to early processing stages, such as stimulus perception and identification. Results of this experiment demonstrated a congruency effect for both reaction time data and zstopping performance. In Experiment 2, these results were replicated with a flanker task that used stimulus-incongruent but response-congruent flankers. Results of both experiments suggest that response inhibition and interference at the early processing stages interact.     

The role of inhibitory control in children's cooperative behaviors during a structured puzzle task

This study examined the role of inhibitory control (measured by Stroop interference) in children’s cooperative behaviors during a structured puzzle task. The sample consisted of 250 8-, 10-, and 12-year-olds (117 girls and 133 boys) attending classrooms in three primary schools in Northern Italy. Children individually completed an elaborated Stroop task, were paired with classmates into 125 dyads, and were observed during a 10-min puzzle task. Results confirmed that interaction partners exhibited similar levels of cooperative behaviors, and the cooperative behaviors of children predicted changes in the cooperative behaviors of their partners throughout the puzzle task. Cooperative behaviors of each interaction partner were predicted by the child’s own inhibitory control as well as the inhibitory control of the partner. Findings are discussed within a developmental contextual framework.     

Assessing inference production in 5 to 7-year-olds: Benefits of using a pictorial task

IntroductionThis study focuses on the methodology used to assess children's inferential skills in a narrative comprehension context with children aged between 5 to 7 years.ObjectiveThe aim of this study is to test the validity of a pictorial task based on children's literature to probe children's ability to make inferences at different times during the listening of fictional stories.MethodThe task involves selecting one of three vignettes which best illustrates what is currently happening in the story (i.e., inferential vs. literal vs. off-topic). The choices expressed here are compared to those made during a preference task performed by the same students, which consists of selecting the vignette they like the most among each series presented in the comprehension task.ResultsFirst, based on the analysis of the data collected in the comprehension task, children most often select inferential vignettes. Second, the choices expressed in the comprehension task differ from those expressed in the preference task.ConclusionThese results confirm the relevance of using children's literature associated with a pictorial task to test children's inferential skills, even with preschoolers.     

Assessing coping strategies: a theoretically based approach

We developed a multidimensional coping inventory to assess the different ways in which people respond to stress. Five scales (of four items each) measure conceptually distinct aspects of problem-focused coping (active coping, planning, suppression of competing activities, restraint coping, seeking of instrumental social support); five scales measure aspects of what might be viewed as emotional-focused coping (seeking of emotional social support, positive reinterpretation, acceptance, denial, turning to religion); and three scales measure coping responses that arguably are less useful (focus on and venting of emotions, behavioral disengagement, mental disengagement). Study 1 reports the development of scale items. Study 2 reports correlations between the various coping scales and several theoretically relevant personality measures in an effort to provide preliminary information about the inventory's convergent and discriminant validity. Study 3 uses the inventory to assess coping responses among a group of undergraduates who were attempting to cope with a specific stressful episode. This study also allowed an initial examination of associations between dispositional and situational coping tendencies.     

Minuchin's psychosomatic family model revised: a concept-validation study using a multitrait-multimethod approach

The convergent and discriminant validity of three operationalizations of the psychosomatic family features--enmeshment, rigidity, overprotectiveness, and lack of conflict resolution, as described by Minuchin and colleagues--are tested in families that include patients with eating disorders, especially anorexia nervosa and bulimia. We redefined the family features as dimensions and measured them with two behavioral methods (direct observation and behavioral product) and a self-report method. The two behavioral methods showed convergent as well as discriminant validity for the intensity of intrafamilial boundaries, the degree of the family's adaptability, and the family's way of handling conflicts. The self-report method showed only convergent validity for the latter dimension and discriminant validity for none of them. Besides intrafamilial conflict, the self-report method seemed to measure other constructs. A factor analysis of the family questionnaire indeed yielded three more evaluative constructs: conflict, cohesion, and disorganization. We interpreted these findings according to two usually interwoven mechanisms: the different research context (insider/outsider evaluation) in self-report and behavioral observation, and the different level of specification (micro/global evaluation) of certain operationalizations. We draw some conclusions about the psychosomatic family model and discuss the clinical implications of our findings.     

Failure to acquire an inhibitory task following seizure-induced brain damage

Male rats that had displayed limbic seizures following a single pair of systemic injections of lithium and pilocarpine were trained 2 months later on an operant schedule that required differential low rates of responding (DRL). The seizured rats never acquired schedules that required either 6-sec. or 12-sec. inhibition of responses following a reward; these rats displayed more perseverative responding and shorter interresponse times than controls. Histomorphology indicated severe brain damage primarily within the entorhinal cortices (and adjacent amygdala) and dorsal thalamus.     

Operator behavior in a dynamic visual signal detection task

The effects of changes in signal-to-noise ratio (SIN) and feedback state on the operator’s detection behavior, particularly derived operator thresholds, were investigated using a discrete visual signal. It was found that: (1) the operator behaves as if he has established different thresholds as a function of S/N; (2) his decision thresholds are relatively independent of the presence or absence of feedback; and (3) the operator will change his threshold accordingly for a change from one S/N to another. A model of the operator’s behavior, which introduced the concept of “operator” noise. yielded predictions of detection and false alarm probabilities which were extremely close to the observed values.     

The relationship between problem solving and inhibitory control: cotton-top tamarin (Saguinus oedipus) performance on a reversed contingency task

To explore the relationship between problem solving and inhibitory control, the authors present 4 experiments on cotton-top tamarins (Saguinus oedipus) using a reverse-reward contingency task. In Experiment 1, 1 group of tamarins was given a choice between a small and a large quantity of food. Whichever quantity the tamarins reached for first, they received the alternative. The tamarins consistently picked the larger quantity, thereby receiving the smaller. A 2nd group of tamarins was given the same task, except that if they reached for the larger quantity of food, they received nothing. The tamarins continued to pick the larger quantity, even though this resulted in no food. In addition, most of the tamarins continued to pick the larger quantity even when the food payoff for choosing the smaller quantity was increased (Experiment 2) or when the visual salience of the food was reduced (Experiment 3). Experiment 4 was based on the finding that chimpanzees (Pan troglodytes) that have been trained on the concept of number can solve the reversed contingency task if the food is replaced by Arabic numerals. With the help of a color association, and a higher cost incurred by picking the color associated with 3 food items, the tamarins learned to pick the color associated with 1 food item. These results are compared with those obtained from studies of other primate species, highlighting the importance of comparative studies of problem solving that use comparable methods.     

Movement control in a reciprocal tapping task: a developmental study

A cross-sectional approach was used to replicate and examine developmental flexibility in eye-hand relationships during alternate tapping performance. A group of 68 male subjects, 34 younger (mean 75.6 months) and 34 older (mean 128.9 months) practiced 12 5-sec trials of alternate tapping in one of three accuracy conditions. Trials 2 and 11 were filmed to determine the eye movement index (EMI), a fraction relating eye movements (numerator) to alternate taps (denominator). Fractional EMI values close to 1 were labelled discontinuity and values closer to 0 (1/N) continuity. Accuracy variation tested the flexibility of EMI for developmental change, revealing that EMIs for older subjects were more continuous than for younger subjects at trial 11, but not at trial 2. Level of EMI was related to age and condition, while change in EMI due to practice was related to age. The data showed EMI strategy flexibility increased with age, and that faster tapping was afforded by less direct visual monitoring of the hand.     

Assessing measurement equivalence across rating sources: a multitrait-multirater approach

Research examining the structure of multisource performance ratings has demonstrated that ratings are a direct function of both who is doing the rating (rating source) as well as what is being rated (performance dimension). A separate line of research has focused on the extent to which performance ratings are equivalent across sources. To date no research has examined the measurement equivalence of multisource ratings within the context of both dimension and rating source direct effects on ratings. We examine the impact of both performance dimension and rating source as well as the degree of measurement equivalence across sources. Results indicate that (a) the impact of the underlying performance dimension is the same across rating sources, (b) the impact of rating source is substantial and only slightly smaller than the impact of the underlying performance dimension, and (c) the impact of rating source differs substantially depending on the source.     

Attempts to control unwanted thoughts in the night: development of the thought control questionnaire-insomnia revised (TCQI-R)

The attempted control of intrusive, uncontrollable thoughts has been implicated in the maintenance of a range of psychological disorders. The current paper describes the refinement of the Thought Control Questionnaire Insomnia (TCQI; Behav. Cogn. Psychoth. 29 (2001)) through its administration to a sample (n=385) including good sleepers and individuals with insomnia. Several items with poor psychometric properties were discarded, resulting in a 35-item revised TCQI. Factor analysis revealed six factors; aggressive suppression, cognitive distraction, reappraisal, social avoidance, behavioural distraction, and worry. The attempted management of unwanted thoughts was compared across individuals with insomnia and good sleepers, and the impact of these strategies on sleep quality, anxiety and depression was investigated. With the exception of cognitive distraction, individuals with insomnia, relative to good sleepers, more frequently used every thought control strategy. The strategies of aggressive suppression and worry, in particular, appeared to be unhelpful, with the use of these strategies predicting sleep impairment, anxiety and depression. The strategy of cognitive distraction appeared to be helpful, with the use of this strategy predicting better sleep quality.     

Attention control and the antisaccade task: a response time distribution analysis

In three experiments response time (RT) differences between correct prosaccade and antisaccade trials were examined via distribution analyses by fitting an ex-Gaussian function to individual RT distributions. Experiment 1 demonstrated that antisaccades are slower than prosaccades and this difference is due to both a shift in the overall distribution as well as a lengthening of the tail of the distribution. Experiment 2 demonstrated that manipulating foreperiod duration led to changes in both accuracy and RT for antisaccades but not prosaccades. Furthermore, the change in RT for antisaccades resulted in a lengthening in the tail of the distribution but not a shift in the distribution. Finally, Experiment 3 demonstrated that with sufficient practice performance on antisaccades was equated with performance on prosaccades in terms of both accuracy and RT. An examination of the RT distributions suggested that practice led to parallel changes in both the mean of the distribution and the tail of the antisaccade distribution. These results are interpreted within a two-factor theory of attention control that suggests that performance on antisaccades is driven by both competition resolution and goal-maintenance abilities.     

Hypnotic control of attention in the Stroop task: a historical footnote

Raz, Shapiro, Fan, and Posner (2002) have recently provided a compelling demonstration of enhanced attentional control under post-hypnotic suggestion. Using the classic color-word interference paradigm, in which the task is to ignore a word and to name the color in which it is printed (e.g., RED in green, say "green"), they gave a post-hypnotic instruction to participants that they would be unable to read. This eliminated Stroop interference in high suggestibility participants but did not alter interference in low suggestibility participants. replicated this pattern and further demonstrated that it is not due to a visual strategy (such as blurring or looking at a different location). As a historical footnote, we describe a "case study" from 18 years ago in which we observed the same result using a hypnotic instruction to a single highly suggestible individual that he could not read. The elimination of Stroop interference has important implications for both the study of attention and the study of hypnosis.