Reaction time methods in the study of motor programming: the precuing of hand, digit, and duration

Recent reaction time analysis of motor programming has utilized a precue stimulus that provides advance information about some or all of the attributes for the upcoming motor response. This kind of precue typically confounds the number of remaining stimuli with the motoric processes under investigation (Zelaznik, 1978). In Experiments 1 and 2 the precuing of hand, digit, and duration of a key press response was manipulated. A new precuing procedure was utilized that does not confound the number of stimuli with the motoric processes under investigation. The findings of Experiments 1 and 2 demonstrate that none of the advance information was helpful in reducing reaction time and as such, suggest that these features of movement are not selected in any particular order. Experiment 3 compared this new method of precuing to the other, traditional method. The results of this experiment suggested that there is parallel processing of the perceptual and motor mental operations in this reaction-time task, since there was an underadditive interaction between the number of stimulus response alternatives and the non-precued movement dimensions. This paper highlights problems inherent in the utilization of precursing methods to understand motor programming processes. It appears that a better understanding about the variables involved in movement control is necessary before examining the order of selection of those variables.     

Ethical issues in cochlear implant surgery: an exploration into disease, disability, and the best interests of the child

This paper examines ethical issues related to medical practices with children and adults who are members of a linguistic and cultural minority known as the DEAF-WORLD. Members of that culture characteristically have hearing parents and are treated by hearing professionals whose values, particularly concerning language, speech, and hearing, are typically quite different from their own. That disparity has long fueled a debate on several ethical issues, most recently the merits of cochlear implant surgery for DEAF children. We explore whether that surgery would be ethical if implants could deliver close to normal hearing for most implanted children, thereby diminishing the ranks of the DEAF-WORLD. The ethical implications of eugenic practices with the DEAF are explored, as are ethical quandaries in parental surrogacy for DEAF children, and their parallels in transracial adoption.     

Sleep,activity, temperature,and performance: Techniques for long-term monitoring in the mouse

This paper describes a test chamber, a food acquisition task, and a training procedure for the long-term testing of an implanted mouse in a circadian rhythm experiment. For the training phase, a special-purpose controller is provided to a single cage. For the experimental phase, behavioral, electrophysiological, and environmental measures are collected by means of a mini-computer.     

Effortful control in early childhood: continuity and change, antecedents, and implications for social development

The course, antecedents, and implications for social development of effortful control were examined in this comprehensive longitudinal study. Behavioral multitask batteries and parental ratings assessed effortful control at 22 and 33 months (N = 106). Effortful control functions encompassed delaying, slowing down motor activity, suppressing/initiating activity to signal, effortful attention, and lowering voice. Between 22 and 33 months, effortful control improved considerably, its coherence increased, it was stable, and it was higher for girls. Behavioral and parent-rated measures converged. Children's focused attention at 9 months, mothers' responsiveness at 22 months, and mothers' self-reported socialization level all predicted children's greater effortful control. Effortful control had implications for concurrent social development. Greater effortful control at 22 months was linked to more regulated anger, and at 33 months, to more regulated anger and joy and to stronger restraint.     

Static scene analysis for the perception of heading

In the current study, we explored observers' use of two distinct analyses for determining their direction of motion, or heading: a scene-based analysis and a motion-based analysis. In two experiments, subjects viewed sequentially presented, paired digitized images of real-world scenes and judged the direction of heading; the pairs were presented with various interstimulus intervals (ISIs). In Experiment 1, subjects could determine heading when the two frames were separated with a 1,000-ms ISI, long enough to eliminate apparent motion. In Experiment 2, subjects performed two tasks, a path-of-motion task and a memory-load task, under three different ISIs, 50 ms, 500 ms, and 1,000 ms. Heading accuracy decreased with an increase in ISI. Increasing memory load influenced heading judgments only for the longer ISI when motion-based information was not available. These results are consistent with the hypothesis that the scene-based analysis has a coarse spatial representation, is a sustained temporal process, and is capacity limited, whereas the motion-based analysis has a fine spatial resolution, is a transient temporal process, and is capacity unlimited.     

In vitro fertilization and the family: quality of parenting, family functioning, and child psychosocial adjustment

This study examined associations between homologous in vitro fertilization (IVF) and quality of parenting, family functioning, and emotional and behavioral adjustment of 3-7-year-old children. A cross-sectional survey was conducted in Taiwan with 54 IVF mother-child pairs and 59 mother-child pairs with children conceived naturally. IVF mothers reported a greater level of protectiveness toward their children than control mothers. Teachers, blind to condition, rated IVF mothers as displaying greater warmth but not overprotective or intrusive parenting behaviors toward their children. Teachers scored children of IVF as having fewer behavioral problems than control children. In contrast, IVF mothers reported less satisfaction with aspects of family functioning. Family composition moderated parenting stress: IVF mothers with only 1 child perceived less parenting stress than did those in the control group.     

An effective approach to violence prevention: traditional martial arts in middle school

This study replicated and extended the design and outcome measures of several small studies. In these studies, juveniles at high risk for violence and delinquency showed decreased violence and positive changes in psychological risk factors after being required to take a school-linked course in traditional martial arts. In the present study, 60 boys in a large urban middle school were required to take a traditional martial arts course in their school. They were paired on problematic behavior profiles and assigned to a treatment group or to a wait-list control group. Thirty classes, three per week (45 minutes each), were taught by a master of Koga Ha Kosho Shorei Ryu Kempo and his assistant (neither was a public school teacher). Results are reported here for 14 variables from the following measures: four teacher rating scales from the Sutter-Eyberg Student Behavior Inventory, five self-report scales of the Piers-Harris Self-Concept Scale, four computerized measures of attentional self-control from the Intermediate Visual and Auditory Continuous Performance Test, and a count of permanent expulsions from school. The treatment students improved over baseline on 12 variables, while the controls improved on 5 by small amounts and deteriorated from baseline on 8, including teacher-rated violence. There were significant differences between the groups on self-reported happiness and schoolwork and on one measure of attention. After controls took the course, their scores resembled the postcourse scores of the treatment group. Importantly, the control group's increase in teacher-rated violence was reversed. Both groups were then pooled to compare baseline and postcourse teacher ratings. Their scores improved significantly in the areas of resistance to rules, impulsiveness, and inappropriate social behavior. There was also improvement in regard to violence, but the change in scores was not statistically significant. Follow-up on teachers' ratings showed that improvement remained, and in some cases increased, four months after completion of the course. Interestingly, all 6 permanent expulsions were among the control group students who had not yet taken, or had only begun taking, the martial arts course.     

Attentional capture and aging: implications for visual search performance and oculomotor control

Two studies examined potential age-related differences in attentional capture. Subjects were instructed to move their eyes as quickly as possible to a color singleton target and to identify a small letter located inside it. On half the trials, a new stimulus (i.e., a sudden onset) appeared simultaneously with the presentation of the color singleton target. The onset was always a task-irrelevant distractor. Response times were lengthened, for both young and old adults, whenever an onset distractor appeared, despite the fact that subjects reported being unaware of the appearance of the abrupt onset. Eye scan strategies were also disrupted by the appearance of the onset distractors. On about 40% of the trials on which an onset appeared, subjects made an eye movement to the task-irrelevant onset before moving their eyes to the target. Fixations close to the onset were brief, suggesting parallel programming of a reflexive eye movement to the onset and goal-directed eye movement to the target. Results are discussed in terms of age-related sparing of the attentional and oculomotor processes that underlie attentional capture.     

Knowing when to move on: cognitive and perceptual decisions in time

We investigated people's ability to decide how much time to spend on the task at hand. To make such decisions well, one must take into account, among other things, the cost of failing and how one's task performance changes as a function of time. We first investigated timing decisions when the underlying task was perceptual. Decisions were highly efficient and suggested that people can make good use of perceptual knowledge and abstract reward information. Previous studies have found that perceptual decisions are generally optimal, but that cognitive decisions are generally suboptimal--a perception-cognition gap. Does a similar gap exist for timing decisions? We compared timing decisions for a perceptual task with timing decisions for more cognitive tasks. Performance was highly similar across the tasks, which suggests that knowledge can be acquired, and used to make timing decisions, in an equally efficient way regardless of whether that knowledge is derived through perceptual or cognitive experience.