Editors can lead researchers to confidence intervals, but can't make them think: statistical reform lessons from medicine

Since the mid-1980s, confidence intervals (CIs) have been standard in medical journals. We sought lessons for psychology from medicine's experience with statistical reform by investigating two attempts by Kenneth Rothman to change statistical practices. We examined 594 American Journal of Public Health (AJPH) articles published between 1982 and 2000 and 110 Epidemiology articles published in 1990 and 2000. Rothman's editorial instruction to report CIs and not p values was largely effective: In AJPH, sole reliance on p values dropped from 63% to 5%, and CI reporting rose from 10% to 54%; Epidemiology showed even stronger compliance. However, compliance was superficial: Very few authors referred to CIs when discussing results. The results of our survey support what other research has indicated: Editorial policy alone is not a sufficient mechanism for statistical reform. Achieving substantial, desirable change will require further guidance regarding use and interpretation of CIs and appropriate effect size measures. Necessary steps will include studying researchers' understanding of CIs, improving education, and developing empirically justified recommendations for improved statistical practice.     

Control over the scheduling of simulated office work reduces the impact of workload on mental fatigue and task performance

Two experiments tested the hypothesis that task-induced mental fatigue is moderated by control over work scheduling. Participants worked for 2 hr on simulated office work, with control manipulated by a yoking procedure. Matched participants were assigned to conditions of either high control (HC) or low control (LC). HC participants decided their own task scheduling, whereas LC participants had to follow these fixed schedules. For Experiment 1, fatigue was higher in LC participants who worked harder, so Experiment 2 compared control effects in high- and low-workload groups. As predicted, the impact of workload was reduced under HC conditions, for subjective fatigue, and most secondary tasks and aftereffects. The findings are interpreted within the framework of compensatory control theory.     

The relationship between measures of executive function, motor performance and externalising behaviour in 5- and 6-year-old children

In his cognitive-energetic model of information processing Sergeant [Sergeant, J. (2000). The cognitive-energetic model: An empirical approach to ADHD. Neuroscience and Biobehavioral Reviews, 24, 7-12] links executive function (EF) to motor behaviour. This link has been supported by evidence from a number of sources including studies of attention deficit hyperactivity disorder (ADHD) and developmental coordination disorder (DCD). Little is known developmentally about this association. Given the rapid change in both motor proficiency and EF that takes place in the pre-school years, this appears an important time to look for the emergence of the link between these factors. In this study we tested 5- and 6-year-old children on motor tasks from the movement assessment battery for children and on measures of response inhibition (Stroop and stop-signal task) and examined the relationship between scores on these measures. Additionally, in order to relate this behaviour to everyday function, the Rowe behavioural rating inventory (RBRI), a teachers' behavioural rating of externalising behaviour, was also gathered and this related to EF and motor performance. It was found that motor performance correlated significantly with RBRI scores (better motor performance with lower externalising behaviour) and with Stroop performance. The relationship between motor performance and stop-signal task performance was in the expected direction but failed to reach significance and there was no clear association between performance on the stop-signal task and either Stroop or RBRI scores. The results are discussed in relation to different aspects of response inhibition (inhibition of a pre-potent response, interference control) and how these might relate to motor control.     

The impact of verbal feedback about blushing on social discomfort and facial blood flow during embarrassing tasks

To investigate whether verbal feedback about blushing influences subsequent social discomfort or blushing itself, changes in facial blood flow and ratings of blushing and embarrassment were investigated in high (N=28) and low scorers (N=28) on the Blushing Propensity scale while singing and reading aloud, and while listening to audiotapes of their performance. After each task half of the participants were told that they had blushed, and the rest were told that they had not blushed. Blood flow increased progressively in participants with high blushing propensity scores who were given "blushing" feedback, but not in the other participants. This finding suggests that expecting to blush may become a self-fulfilling prophecy. Verbal feedback about blushing strongly influenced subsequent social discomfort, and mimicked the effects of blushing propensity on ratings of embarrassment and blushing intensity. In sum, the findings support the view that preconceptions about blushing propensity are shaped by past learning experiences, that concern about blushing is a major source of discomfort in embarrassing situations, and that these concerns are often unrelated to the actual intensity of blushing.     

Navigating the narrative: An eye-tracking study of readers' strategies when Reading comic page layouts

In multimedia stimuli (e.g., comics), the reader must follow a narrative in which text and image both contribute information, and artists may use more irregular layouts which must still be followed correctly. While previous work has found that the external structure (outlines) of panels is a major contributor to navigation decisions in comics, other studies have shown that panel content can affect reading order. The present studies use eye-tracking to investigate these contributions further. In Experiment 1, the reading behaviors on six layout variations were compared. The influence of the external structure was replicated, but an effect of text location was also found for one layout type. Experiment 2 focused on variations of this particular layout, manipulating the location of text within critical panels. Panel content was a consistent effect for all variations. While most navigation decisions are made using the external structure, content becomes key when resolving ambiguous layouts.     

Managing group process in nonprocess groups: Working with the theme-centered psychoeducational group

While there has been a recent proliferation of groups for consultative and psychoeducational purposes, little has been written about using the group process in these nonprocess groups. This paper investigates the management of various group processes in a group whose contracted focus is teaching stress management skills. Distinctions are made between psychotherapeutic and theme-centered psychoeducational process management. Many group processes can be predicted given the group's normal developmental stages, while other ongoing group processes arise spontaneously. A working dialogue between the presented content and the emerging process is necessary in order for psychoeducation to be personalized and most fully assimilated. A clinical vignette follows the evolution of a stress management group conducted for high-level executives who have been identified as manifesting Type-A behaviors. For each session, the format and material content are briefly outlined, the emerging group process is described, and the clinical interventions involved in the process management are discussed.     

Molar optimization versus delayed reinforcement as explanations of choice between fixed-ratio and progressive-ratio schedules.

In a discrete-trials procedure, pigeons chose between a fixed-ratio 81 schedule and a progressive-ratio schedule by making a single peck at the key correlated with one or the other of these schedules. The response requirement on the progressive-ratio schedule began at 1 and increased by 10 each time the progressive-ratio schedule was chosen. Each time the fixed-ratio schedule was chosen, the requirement on the progressive-ratio schedule was reset to 1 response. In conditions where there was no intertrial interval, subjects chose the progressive-ratio schedule for an average of about five consecutive trials (during which the response requirement increased to 41), and then chose the fixed-ratio schedule. This ratio was larger than that predicted by an optimality analysis that assumes that subjects respond in a pattern that minimizes the response-reinforcer ratio or one that assumes that subjects respond in a pattern that maximizes the overall rate of reinforcement. In conditions with a 25-s or 50-s intertrial interval, subjects chose the progressive-ratio schedule for an average of about eight consecutive trials before choosing the fixed-ratio schedule. This change in performance with the addition of an intertrial interval was also not predicted by an optimality analysis. On the other hand, the results were consistent with the theory that choice is determined by the delays to the reinforcers delivered on the present trial and on subsequent trials.     

Dissociation of value and response strength

Four pigeons were exposed to multiple schedules and later to concurrent-chains schedules, with terminal links that had previously been multiple-schedule components. For 2 birds, the terminal-link schedules arranged an inverse relationship between response rate and reinforcement rate; for the other 2 birds a direct corresponding relationship was arranged. Those response rates were further modified by differentially reinforcing either longer or shorter interresponse times, relative to the current means. Although the birds' initial-link responses indicated preferences for terminal links with higher rates of reinforcement, in half the cases the birds responded during the terminal links in such a way as to produce lower rates of reinforcement, rates their initial-link behavior indicated they did not prefer. That outcome is inconsistent with maximization theory, but consistent with a strengthening analysis of behavior on single-key schedules.     

Teaching pigeons an abstract relational rule: insideness

In 49 sessions, pigeons failed to learn to sort a collection of 80 stimuli composed of a closed curve and a dot, divided into two categories, according to whether the dot was or was not inside the curve. Next, the pigeons were successfully trained, first with the insides of the curves shown in bright red, then with a darker red, and finally with a black matching the background outside the curve. After this stepwise procedure, the pigeons displayed a limited ability to sort novel curves and dot locations according to whether the dot was or was not inside the curve.