Evidence for an Error Detection Mechanism In Motor Skills

One of the fundamental predictions of the Adams (1971) closed-loop theory is that S should develop over practice a perceptual trace which forms the basis of an error detection mechanism. If knowledge of results (KR) is withdrawn, S can use the error detection mechanism to guide performance in its place. To test this notion, 10 Ss practiced 170 trials of a discrete ballistic response, attempting to produce a 9.5-in. manual slider movement in exactly 150 msec., with KR present except on Trials 11-20 and 141-170. There was an increasing correspondence between the actual errors and Ss’ estimation of them as practice continued, and ratings of confidence increased, both of which were indicative of a developing error detection mechanism. During KR withdrawal trials, Ss displayed no worsening of performance, and even continued to learn slightly, suggesting that the error detection mechanism acted as a substitute for KR. The results generally supported Adams’ theory.     

Linguistic and nonlinguistic influences on the eyes' landing positions during reading

Two eye tracking experiments show that, for near launch sites, the eyes land nearer to the beginning of words with orthographically irregular than with regular initial letter sequences. In addition, the characteristics of words, at least at the level of orthography, influence the direction and length of within-word saccades. Importantly, these effects hold both for lower case and for visually less distinctive upper case text. Furthermore, contrary to previous evidence (Tinker & Paterson, 1939), there is little effect of type case on reading times. Additional analyses of oculomotor behaviour suggest that there is an inverted optimal viewing position for single fixation durations on words. Both the supplementary analyses and the effects of orthography on fixation positions are relevant to current models of eye movements in reading.     

Expanding on cross-price elasticity: Understanding tobacco product demand and substitution from the cross-price purchase task

We examine whether cigarettes serve as substitutes for electronic nicotine delivery systems (ENDS) among ENDS users and demonstrate methodological extensions of data from a cross-price purchase task to inform policies and interventions. During a clinical laboratory study, n = 19 exclusive ENDS users and n = 17 dual cigarette/ENDS users completed a cross-price purchase task with cigarettes available at a fixed price while prices of own-brand ENDS increased. We estimated cross-price elasticity using linear models to examine substitutability. We defined five additional outcomes: nonzero cross-price intensity (purchasing cigarettes if ENDS were free), constant null demand (not purchasing cigarettes at any ENDS price), cross-product crossover point (first price where participants purchased more cigarettes than ENDS), dual-demand score (percentage of prices where both products were purchased), and dual-use break point (minimum relative price to force complete substitution). The cross-price elasticity results indicated that cigarettes could serve as substitutes for ENDS among ENDS users on average, but this average effect masked substantial heterogeneity in profiles of demand (here, a measure of the drug's reinforcement potential). Policies and regulations that increase ENDS prices appear unlikely to steer most exclusive ENDS users toward cigarette use, as most would not purchase cigarettes at any ENDS price, but they could prompt some dual users to substitute cigarettes completely while others remain dual users. This heterogeneity in consumer responses suggests additional indices of cross-product demand are useful to characterize the anticipated and unanticipated effects of tobacco price policies more fully.     

The Influence of Anticipatory Processing on Attentional Biases in Social Anxiety

Research on cognitive theories of social anxiety disorder (SAD) has identified individual processes that influence this condition (e.g., cognitive biases, repetitive negative thinking), but few studies have attempted to examine the interaction between these processes. For example, attentional biases and anticipatory processing are theoretically related and have been found to influence symptoms of SAD, but they rarely have been studied together (i.e., Clark & Wells, 1995). Therefore, the goal of the current study was to examine the effect of anticipatory processing on attentional bias for internal (i.e., heart rate feedback) and external (i.e., emotional faces) threat information. A sample of 59 participants high (HSA) and low (LSA) in social anxiety symptoms engaged in a modified dot-probe task prior to (Time 1) and after (Time 2) an anticipatory processing or distraction task. HSAs who anticipated experienced an increase in attentional bias for internal information from Time 1 to Time 2, whereas HSAs in the distraction condition and LSAs in either condition experienced no changes. No changes in biases were found for HSAs for external biases, but LSAs who engaged in the distraction task became less avoidant of emotional faces from Time 1 to Time 2. This suggests that anticipatory processing results in an activation of attentional biases for physiological information as suggested by Clark and Wells.     

Follow-up effects of social comparison information on the quality of life of cancer patients: The moderating role of social comparison orientation

Objective: To examine how social comparison orientation (SCO) moderates the effects of three types of social comparison information on the global quality of life of cancer patients 2 weeks and 3 months later. Design: Cancer patients (n?=?226) were provided with social comparison information just prior to undergoing radiation therapy, using audiotapes. Each participant was confronted with one of three tapes: (1) focusing on procedural aspects, (2) focusing on emotional reactions and (3) focusing on coping strategies. Main outcome measures: Quality of life as measured with the Cantril self-anchoring scale [Cantril, H. (1965). The pattern of human concerns. New Brunswick, NJ: Rutgers University Press]. Results: With increasing SCO, a lower quality of life was reported after listening to the emotion tape, while a higher quality of life was reported after listening to the coping tape. These effects were found 2 weeks as well as 3 months after the radiation therapy had ended. Conclusion: Social comparison information may have longitudinal effects on quality of life, but these effects are to an important extent dependent on the nature of the information and individual differences in SCO.     

Crowd Effects in Unfamiliar Face Matching

Psychological research shows that humans can not reliably match unfamiliar faces. This presents a practical problem, because identity verification processes in a variety of occupational settings depend on people to perform these tasks reliably. In this context, it is surprising that very few studies have attempted to improve human performance. Here, we investigate whether distributing face matching tasks across groups of individuals might help to solve this problem. Across four studies, we measure the accuracy of the ‘crowd’ on a standard test of face matching ability and find that aggregating individual responses produces substantial gains in matching accuracy. We discuss the practical implications of this result and also suggest ways in which this approach might be used to improve our understanding of face perception more generally. Copyright © 2013 John Wiley & Sons, Ltd.     

A Multiple-Task Measurement Framework for Assessing Maximum-Typical Performance

This study presents a novel measurement framework for assessing and predicting maximum and typical performance. The proposed measurement approach addresses the need for organizations to assess maximum and typical performance changes over time in complex job settings requiring coordination of multiple tasks with changing priorities. We present results of an experiment in which participants engaged in a complex task with multiple task elements and instructions to either maximize a different task element in each of four performance blocks (variable-priority condition) or treat all task elements with equal priority (stable-priority condition). We estimated growth curves corresponding to each task element and calculated the area under each growth curve as a summary performance index. Growth curves corresponding to the maximized, high-priority task element in the variable-priority condition reflected maximum performance, whereas those corresponding to the deemphasized, lower priority elements reflected typical performance. We compared the shape of the maximum and typical growth curves in the variable-priority condition to their corresponding performance trajectories in the stable-priority condition. In addition, we tested the moderating influence of individual differences in action-state orientation on the obtained maximum and typical performance estimates. Results indicated support for the proposed measurement framework in terms of its usefulness for inducing sustained levels of maximum performance and for identifying and correcting sources of the maximum-typical performance discrepancy.