Additive factors analysis of reaction time with alphanumericals and line orientations as stimuli

Most additive factors method (AFM) analyses of choice reaction time (CRT) have used alphanumerics whereas tests of single process models have often used line length or line orientation. The suggestion is raised that commonly observed additive effects of variables on CRT might not apply to stimuli of the latter category. This would mean a severe limitation of the AFM in that the stage structure of choice reactions would be stimulus specific. The issue is addressed in two experiments. The first showed additive effects of stimulus quality and stimulus-response compatiblility for both alphanumerics and line orientations as stimuli. The second showed that for both stimulus categories the effect of stimulus quality was fully reflected in visual fixation time. Together the results argue against a single central process and favour a stage model of CRT.     

Are changes in beliefs and attitudes about sleep related to sleep improvements in the treatment of insomnia?

Dysfunctional beliefs and attitudes about sleep are presumed to play an important mediating role in perpetuating insomnia. The present study evaluated the impact of cognitive-behavioral and pharmacological treatments for insomnia on sleep-related beliefs and attitudes and the relationship between those changes and sleep improvements. The participants were older adults with chronic and primary insomnia. They received cognitive-behavior therapy (CBT), pharmacotherapy (PCT), combined CBT+PCT (COMB), or a medication placebo (PLA). In addition to daily sleep diaries and sleep laboratory measures, the participants completed the dysfunctional beliefs and attitudes about sleep scale (DBAS) at baseline and posttreatment, and at 3-, 12- and 24-month follow-up assessments. The results showed that CBT and COMB treatments produced greater improvements of beliefs and attitudes about sleep at posttreatment than PCT and PLA. Reductions of DBAS scores were significantly correlated with improvements of sleep efficiency as measured by daily sleep diaries and by polysomnography. In addition, more adaptive beliefs and attitudes about sleep at posttreatment were associated with better maintenance of sleep improvements at follow-ups. These findings highlight the importance of targeting sleep-related beliefs and attitudes in the treatment of insomnia.     

Processing speed in the 1st year of life: a longitudinal study of preterm and full-term infants

Processing speed was assessed at 5, 7, and 12 months in full-term and preterm infants (birth-weight < 1,750 g). Speed was gauged directly in a new task by presenting infants with a series of paired faces, one that remained the same across trials and one that changed; trials continued until infants showed a consistent novelty preference. At all ages, preterms required about 20% more trials and 30% more time than full-terms to reach criterion. Among preterms, slower processing was associated with greater medical risk (e.g., respiratory distress syndrome). Developmental trajectories for speed (and attention) were similar for both groups. Thus, the deficits in processing speed previously found for preterms in childhood are already present in the 1st year of life.     

Changing the guard: new leadership for an established group

When the leader of an established therapy group decides to leave, the group may wish to continue with a new leader. This decision deserves careful exploration. The transfer of leadership to a new leader is a powerful event in a group. New leaders often experience strong countertransference reactions. Specific recommendations for new leaders include meeting individually with each continuing member, helping the group stabilize and process the meaning of the change, and developing ownership of the leader role. When managed successfully, a leadership transition can strengthen the group cohesion and offer important therapeutic opportunity.     

List of Contributors

Authors Index

List of Contributors     

Operant-contingency-based preparation of children for functional magnetic resonance imaging

Functional magnetic resonance imaging (fMRI) is used to study brain function during behavioral tasks. The participation of pediatric subjects is problematic because reliable task performance and control of head movement are simultaneously required. Differential reinforcement decreased head motion and improved vigilance task performance in 4 children (2 with behavioral disorders) undergoing simulated fMRI scans. Results show that behavior analysis techniques can improve child cooperation during fMRI procedures.     

Acceptability of personal hormone monitoring for contraception: longitudinal and contextual variables

A new contraceptive technology may advance the science of family planning but may do little to affect health if potential users do not deem it an acceptable method. The authors conducted an acceptability study of a newly developed contraceptive method--personal hormone monitoring. A sample of 480 English volunteers present at the 6th month of a 13-month longitudinal study completed surveys regarding their attitudes toward a personal hormone monitor for the purpose of contraception. The authors used the participants' responses to determine (a) the extent to which the participants accepted the monitor, (b) how their ratings of acceptability changed over time, (c) the extent to which contextual variables predicted changes in acceptability over time, and (d) whether those contextual variables predicted final acceptability of the monitor. Results suggested that no single method of family planning is best for everyone and specified the people for whom personal hormone monitoring may be most suitable.     

Acculturation,stress, and depressive symptoms among Korean immigrants in the United States

A sample of 157 Korean immigrants responded to measures of acculturation level, stress from acculturation, and depressive symptoms. The authors hypothesized that adaptive acculturation would depend on assimilation regarding social interactions and the host culture's language as well as on retention of a core identity, including values and traditions of the culture of origin. Consistent with the mediation hypothesis, acculturation, based on a factor representing language use and social relationships, was related to lower acculturative stress and, in turn, lower depression. However, there was no direct support for the integrative, or bicultural, strategy of acculturation. Stress did not mediate the effect of a 2nd acculturation factor, identity and tradition-based acculturation. Rather, this measure of acculturation was directly related to higher depression (i.e., immigrants reporting abandonment of Korean identity, traditions, and values scored higher for depression).     

The formation of a generalized categorization repertoire: effect of training with multiple domains,samples, and comparisons

The present experiment explored the effects of three variables on the spontaneous categorization of stimuli in perceptually distinct and novel domains. Each of six stimulus domains was created by morphing two images that were the domain endpoints. The endpoints of the domains were male and female faces, two abstract drawings, a car and a truck, two banded-elevation satellite land images, a tree and a cat, and two false-color satellite images. The stimulus variants at each end of a domain defined two potential perceptual classes. Training was conducted in a matching-to-sample format and used stimuli from one or two domains, one or three variants per class as samples, and one or three variants per class as comparisons. The spontaneous categorization of stimuli in the untrained stimulus domains showed the emergence of a generalized categorization repertoire. The proportion of spontaneously categorized stimuli in the new domains was positively related to the number of domains and samples used in training, and was inversely related to the number of comparisons used in training. Differential reaction times demonstrated the discriminability of the stimuli in the emergent classes. This study is among the first to provide an empirical basis for a behavior-analytic model of the development of generalized categorization repertoires in natural settings.     

Repeatability of mae-geri-keage in traditional karate: a three-dimensional analysis with black-belt karateka

In karate, performance also depends on a correct body shape, and the repeatability of standardized movements conditions the effectiveness of techniques. The execution of mae-geri-keage (frontal snap kick) was studied in 13 karateka (1st-5th dan). The 3D trajectories of 13 body landmarks were analyzed by an optoelectronic instrument while each karateka performed 10 repetitions of the movement. For each karateka and repetition, the standard deviations of the spatial coordinates x, y, z for each landmark were computed. A total standard deviation of the single participant was also calculated. Two experienced karateka performed with the best repeatability (smaller standard deviation) while executing the studied kick. Generally, the best repeatability was observed in the horizontal plane. The lower variability was observed in hips and head. Ankle and knee of the dominant limb had the worse. The method could detect athletes particularly gifted for the discipline. Moreover, it could help in the identification of those parts of body that do not repeat the movement with the desired precision.