Inhibiting prepared and ongoing responses: Is there more than one kind of stopping?

Inhibiting movements has been investigated widely using the countermanding (stop signal) paradigm. Although it has been assumed that response inhibition, as measured by the countermanding task, generalizes to all forms of stopping, this has never been tested. In the present study, stopping performance in the countermanding paradigm was compared with stopping performance in a new paradigm in which a continuous-tracking task was used. Although stimulus presentations were matched across paradigms, the two tasks differed in the type of stopping required. In the countermanding paradigm, response inhibition latency was measured prior to response execution-this is, it was inferred from the successful withholding of a go response. In the new paradigm, response inhibition was carried out after response execution-that is, it was measured as the time to begin stopping a continuous tracking response. Results indicated that stopping latencies between the two paradigms were highly correlated, providing strong evidence that stopping an unexecuted response engages the same mechanisms as stopping an ongoing response.     

Political support for self-determination,wealth, and national subjective well-being

The present paper explored the relation of wealth and support for self-determination to national subjective well-being (SWB). Support for self-determination was considered from both a political and cultural values standpoint. The results confirmed associations between wealth, support for self-determination, and well-being in a large sample of countries. Importantly, political and cultural value supports for self-determination remained significantly associated with national well-being (as measured by happiness reports and life expectancy) even after controlling for national differences in wealth.

Distinguishing highly confident accurate and inaccurate memory: insights about relevant and irrelevant influences on memory confidence

It is generally believed that accuracy and confidence in one's memory are related, but there are many instances when they diverge. Accordingly it is important to disentangle the factors that contribute to memory accuracy and confidence, especially those factors that contribute to confidence, but not accuracy. We used eye movements to separately measure fluent cue processing, the target recognition experience, and relative evidence assessment on recognition confidence and accuracy. Eye movements were monitored during a face-scene associative recognition task, in which participants first saw a scene cue, followed by a forced-choice recognition test for the associated face, with confidence ratings. Eye movement indices of the target recognition experience were largely indicative of accuracy, and showed a relationship to confidence for accurate decisions. In contrast, eye movements during the scene cue raised the possibility that more fluent cue processing was related to higher confidence for both accurate and inaccurate recognition decisions. In a second experiment we manipulated cue familiarity, and therefore cue fluency. Participants showed higher confidence for cue-target associations for when the cue was more familiar, especially for incorrect responses. These results suggest that over-reliance on cue familiarity and under-reliance on the target recognition experience may lead to erroneous confidence.     

Tuning characteristics of the top-down attentional setting

Previous studies of top-down attentional guidance have focused generally on the attentional prioritization of a single target feature. The present study focused on how the attentional system would be configured when the target possesses several unique features. These features were perfectly correlated, which meant that monitoring just one of them would be an adequate strategy. The experiments addressed the following questions: (a) If the target is a singleton, would the attentional system be set to monitor the target’s unique features, or would the search strategy default to singleton detection? (b) Can the target’s static and dynamic features be prioritized simultaneously? (c) Are all of the target’s features prioritized, or only those features that are diagnostic of targethood? The results revealed an attentional system that can be flexibly tuned to multiple target features across static and dynamic dimensions. This system can simultaneously be narrowly tuned to monitor a specific target feature and broadly tuned to detect singletons. Finally, the attentional system monitors only those features that are diagnostic of targethood.     

The Role of Video in Facilitating Perception and Action of a Novel Coordination Movement

Two groups (n = 10 in each) practiced a novel, bimanual coordination pattern that was demonstrated on video. One of the groups received augmented video feedback of their own responses after each trial following a demonstration. The video-feedback group showed better performance in acquisition and retention than the no-feedback group. On error-detection tests, the video-feedback group was better able to distinguish between correct and incorrect movement patterns. The authors concluded that video feedback helps to make relative phase information salient by aiding the discrimination process. Prepractice ability on a scanning task revealed that individuals who persevered with inphase-type movements, even though the task demands dictated otherwise, had the most difficulty determining and subsequently performing the required movement. Video feedback helped them to compensate for those difficulties.     

Anchoring strategies for learning a bimanual coordination pattern

Anchoring has been defined as synchronizing a point in a movement cycle with an external stimulus (W. D. Byblow, R. G. Carson, & D. Goodman, 1994). Previously, investigators have examined anchoring during in-phase and antiphase movements. The present authors examined anchoring during acquisition of a novel bimanual coordination pattern. Participants performed a 90 degrees pattern at 1 Hz, with a 2- or 4-Hz metronome. No group differences were found in pattern performance; however, the 4-Hz group developed more consistent anchoring relative to the metronome. Mechanical anchor-point variability differed by hand, position (midpoint vs. endpoint), and direction (flexion vs. extension) but not by metronome frequency. Those results support and extend previous findings but leave unanswered questions regarding the benefits and effectiveness of anchoring during a 90 degrees pattern.     

Reprogramming of interceptive actions: time course of temporal corrections for unexpected target velocity change

The authors investigated the time course of reprogramming of the temporal dimension of motor acts in a task requiring interception of a moving target. The target moved at a constant velocity on a monitor screen; in part of the trials, target velocity was unexpectedly increased or decreased. Those modifications were produced at different moments during target displacement, leaving periods of time from 100 to 800 ms for movement timing correction. The authors assessed the effects of probability of target velocity change (25% vs. 50%), uncertainty about direction of velocity change (unidirectional vs. bidirectional), and direction of velocity change (increase vs. decrease). Analysis of 24 participants' arm acceleration showed that fast adjustments took place between 100 and 200 ms after target velocity change similarly for all uncertainty conditions. Analysis of temporal error indicated that the combination of high probability of target velocity change and certainty on direction of target velocity change led to the most successful movement timing reprogramming. For the other experimental conditions, temporal accuracy was still poor when a period of 800 ms was available for correction. Movement reprogramming was a continuous process that was more efficient for target velocity increase than for target velocity decrease.     

Compatibility effects in stopping and response initiation in a continuous tracking task

Two experiments explored stopping performance using a new stimulus-response compatibility effect spanning action initiation and stopping. Participants tracked a sometimes-moving, sometimes-stationary target by controlling the speed of a response marker via a force sensor. In the compatible condition, participants pressed the sensor in response to the target moving and stopped pressing in response to the target stopping. In the incompatible condition, participants stopped pressing in response to the target moving and initiated pressing in response to the target stopping. Response initiation and stopping were found to be faster under compatible than under incompatible conditions, regardless of whether compatible and incompatible trials were blocked or mixed. These findings indicate that stopping, like response initiation, is influenced by stimulus-response properties such as compatibility. This in turn suggests that stopping is governed by constraints similar to those of other behaviours.