Influence of instruction on velocity and accuracy of overarm throwing

This study investigated the influence of instruction on the ball velocity and accuracy of a goal-directed overarm throw. 9 experienced Norwegian male team handball players executed a throwing task randomly seven times under 5 different instructions varying from emphasizing speed to accuracy. When instructions increasingly emphasized accuracy, velocity decreased. However, accuracy did not improve when subjects were instructed to focus on it. A possible explanation for this finding could lie in the specific subject group. The subjects were highly experienced team handball players with an average of 12 years in the sport. Thus, the accuracy they demonstrated at high velocity might actually be already extremely high and difficult to improve upon when reducing throwing velocity. Further, the velocity of throwing when instruction emphasized accuracy was approximately 85% of the maximal velocity, indicating that experienced team handball players are trained to throw accurately at relatively high velocity.     

Effectiveness Evaluation of Search and Target Acquisition Training Prototype Using Performance Metrics With Eye-Tracking Data

Despite the increased use of sensor technologies, including unmanned vehicles, the vast majority of improvised explosive device (IED) detections are made by human vision. Thus, TRAC-Monterey developed a simulation-based training prototype called the perceptual learning trainer (PLT). Fourteen novice and 5 expert IED detectors participated in human-in-the-loop experiments in which all participants were trained using the PLT tool while their eye-movement and IED detection performance were tracked in real-time. A series of 100 IED images with various degrees of difficulty was used for the training session. Pre- and posttraining assessments were conducted. Both speed and accuracy improved after just 1 session of the PLT training: RT decreased by 3.7 s for novices (p < .001) and 3.4 s for experts (p = .031), and detection probability increased by 5.9% for novices (p = .001). The PLT tool improved IED detection performance more in novice IED detectors than in experts. Novices and experts showed different visual scan patterns.     

Practice variability and children's motor behavior

This research investigated Schmidt's variability-of-practice prediction and the breadth-of-a-movement class. Schmidt's hypothesis was tested by varying the parameters of ball and distance in overarm throwing. Breadth-of-a-movement class was tested by employing two novel tasks not previously used in variability-of-practice designs. 203 kindergarten and first-grade subjects were randomly assigned to one of four conditions, three experimental and one control. Experimental subjects performed 45 trials in their respective training conditions, weight, distance, weight/distance, in one session. Two novel striking tasks were administered to all subjects pre- and posttest to assess the variability-of-practice hypothesis, and the generalizability of overarm throwing and striking. Variability-of-practice in the overarm throw appeared to strengthen the striking schemas of the kindergarten boys. Results suggest some support for the inclusion of throwing and striking in a single-movement class. The concept, breadth of movement class, however, requires further study.     

Diagnosing fictional diseases: age and variability of training content in concept formation

This experiment had two purposes: investigation of the effect of variability in the content used during training on concept learning, retention, and transfer and the extent to which this training manipulation interacts with age. Participants were 27 older adults (M = 68.2 yr., SD = 7.4) and 54 younger adults (M = 20.6 yr., SD = 4.0) who were asked to learn an imaginary disease by reviewing the symptoms of fictional patients. Participants were assigned to one of two variability groups in training, which were defined by how much patient cases resembled each other. Dependent measures were classification accuracy over eight blocks of training, followed by retention and transfer ("diagnosing new patients") two days later. Analysis of variance yielded only one significant interaction of age and training variability (on retention), but none of the paired comparisons were significantly different. There were no main effects of training group on any dependent variable.     

Effect of physical fatigue on motor control at different skill levels

The purpose of this experiment was to explore the effect of fatigue on motor coordination, and of prospective adjustment strategies to compensate for fatigue in a multijoint movement. Two male groups (N = 8) participated in the experiment: Highly skilled table tennis players (M age = 27 yr., SD = 2.3, n = 4) and Recreational table tennis players (M age = 25.9 yr., SD = 0.04, n = 4). The task was an attacking forehand drive towards a scaled target on the opposite side of the net. The Highly skilled players adjusted their movement patterns and preserved the task requirements in terms of spatial accuracy under the condition of fatigue by using opportunistic movement coordination. The Recreational players did not adjust their forehand drive, and spatial accuracy deteriorated. The current results support the notion that expertise enhances potential to adjust motor coordination strategies as a reaction to induced physical fatigue.     

Diagnostic classification by experts and novices.

The present study examines differences between experts and novices in classifying symptoms and the effect of the nature of the task on classifying. The study involved three groups of subjects, two expert groups (n = 12, n = 10) and one novice group (n = 12). Thinking-aloud protocols were collected for two classification tasks: sorting of behavioural symptoms into predefined categories and intuitive clustering of behavioural symptoms. In a third task, experts and novices were asked to make typicality ratings of behavioural symptoms. The protocols were analyzed with respect to seven cognitive operations: (a) asking or giving information, (b) associating, (c) abstracting or labelling, (d) explaining, (e) neutral matching, (f) identifying, and (g) differentiating. Results showed an effect of experience and an effect of the task on the relative frequencies of these operations. No differences were found in typicality rating of experts versus novices. These contradictory findings are discussed in relation to Kolodner's model about the evolution of expertise.     

Young girls' developmental skills in underarm throwing

This paper concerns underarm throwing by girls 7 to 12 years of age. Each movement component by trained and untrained girls in underarm throwing or windmill softball pitching was examined. Movement characteristics of ball release, arm motion, trunk activity, and stepping were analyzed to capture experience- and age-related differences in underarm throwing. A total of 48 young girls participated: 25 untrained (age 9.7 yr.), 14 trained/league (age 10.9 yr.), and 9 trained/formal (10.4 yr.). Performance was videotaped individually and evaluated by three observers. Analyses suggest that, while age did not affect performance, the type of training experience influenced the girls' performance on each of the four movement components. The wrist and trunk were identified as showing the most significant progression with experience. The findings have important implications about changes during acquisition of underarm throwing skills.     

Judgment and decision-making: experts' and novices' evaluation of chess positions

The present study examined how experts differ from nonexperts in estimation and evaluation during a judgment-and-decision task. In the experiment, the performance of 125 chess players (21 women and 104 men) whose mean age was 32.5 yr. (SD = 13.3) was examined to assess decision processes with an emphasis on postdecision differentiation and consolidation. Chess players of differing skill made evaluations of a complex middle-game chess position. The experimental condition was made by the means of chess articles with enclosed information, either about the current chess position or about other similar positions. Both novices and experts upgraded their chosen alternative in a postdecision phase more than intermediate level chess players did. Various explanations of these results are discussed.     

Transfer of training for two ball-throwing tasks

The effects of training overhand ball throws to enhance underhand ball-throwing accuracy were studied with 921 Italian high school pupils (575 girls, M age = 16.5 yr., SD = 1.3; 346 boys, M = 16.5 yr., SD = 1.2) ages 14 to 18 years. A standardized test (10 underhand tennis-ball throws into the floor area delimited by an 80-cm radius wooden hoop lying on the floor 9 m from the standing pupil) was performed and scored. An Experimental group (435 girls, M age = 16.5 yr., SD = 1.3; 204 boys, M age = 16.5 yr., SD = 1.2) was randomly selected to participate in 10 weekly training periods. The set included 10 overhand throws of a rubber bouncing ball (14.5 cm diameter, weight 240 g) into a basketball hoop from 5 standardized positions (in front of the basketball hoop; at 45 degrees, 90 degrees on the right and on the left of the basketball hoop) at a distance of 4.40 m. The underhand test was repeated for both groups. On the average, boys obtained higher test scores than girls of the same age. Older adolescents had higher mean scores than younger adolescents. After 10 weeks, boys and girls of all ages improved. Mean differences between sessions were significant for the Experimental group (Student t test, p < .01). In Session 2, consistent differences between Experimental and Control groups were also found (Student t test, p < .05).     

Integrating fundamental movement skills in late childhood

The study examined how children of different ages integrate fundamental movement skills, such as running and throwing, and whether their developmental status was related to the combination of these skills. Thirty children were divided into three groups (G1 = 6-year-olds, G2 = 9-year-olds, and G3 = 12-year-olds) and filmed performing three tasks: running, overarm throwing, and the combined task. Patterns were identified and described, and the efficiency of integration was calculated (distance differences of the ball thrown in two tasks, overarm throwing and combined task). Differences in integration were related to age: the 6-year-olds were less efficient in combining the two skills than the 9- and 12-year-olds. These differences may be indicative of a phase of integrating fundamental movement skills in the developmental sequence. This developmental status, particularly throwing, seems to be related to the competence to integrate skills, which suggests that fundamental movement skills may be developmental modules.     

Unwanted early sexual experiences among Belgian and South African university women students

This study examined the unwanted early sexual experiences of 736 South African and 1,587 Belgian women students. The Early Sexual Experiences Checklist was administered to all consenting women students attending orientation programmes at a Belgian and a South African university. Respondents were Belgians (M age = 18.2 yr., SD = 1.0) and South Africans (M age = 19.6 yr., SD = 4.1). Such experiences were found for 31.3% (231) of South African respondents and 14.2% (226) of Belgian respondents. 64% of South African women indicated that such an experience occurred only once, and 65% of Belgian women reported this also. 34% of Belgian and 32% of South African respondents reported not being bothered at all by the unwanted experience at the time the event took place; 23% of Belgian and 36% of South African respondents were extremely bothered by the experience.     

Influence of Domain Knowledge on Monitoring Performance Across the Life Span

Two studies were conducted to investigate effects of domain knowledge on metacognitive monitoring across the life span in materials of different complexity. Participants from 4 age groups (3rd-grade children, adolescents, younger and older adults) were compared using an expert–novice paradigm. In Study 1, soccer experts’ and novices’ ease-of-learning judgments (EOLs), judgments of learning (JOLs), and confidence judgments (CJs) were contrasted when memorizing soccer-related word pairs. In Study 2, monitoring judgments (i.e., a rating of global comprehension, JOLs, and CJs) were collected in regards to a soccer-related narrative. The results of both approaches showed that experts’ better memory performance obtained in both studies was not always accompanied by advantages in monitoring performance. In Study 1, experts of all ages outperformed novices in monitoring accuracy. In Study 2, no benefits of expertise on monitoring were found; in children, novices even surpassed experts in monitoring quality. In both studies, the most consistent influence of previous domain knowledge on monitoring performance concerned more optimistic judgments of experts compared with novices, regardless of stimuli and recall format. In sum, our results document a twofold effect of expertise on monitoring. Although domain-specific knowledge enhances monitoring performance in some situations, more optimistic estimates, presumably due to the application of a familiarity heuristic, typically reduce experts’ monitoring accuracy.     

Accuracy of movement speed and error detection skills in adolescents with cerebral palsy.

People with cerebral palsy (CP) usually have decreased ability to learn new movements and decreased movement speed. This study examined the ability of 10 adolescents with CP (M age = 16.2 yr., SD = 1.9 yr.) to achieve a target speed on an tipper extremity ballistic task and to detect speed errors in their movements, compared to the performance of 10 adolescents with no disability (M age = 15.7 yr., SD = 1.7 yr.). Subjects were instructed to slide a lever along a track in 150 msec., then guess their movement time. Knowledge of results feedback was provided on the first 50 trials except for Trials 11-20 on Day 1. Knowledge of results feedback was withheld on Day 2, Trials 51-60, to assess learning and retention of the skill. Speed Error and Error Detection were compared for two groups of adolescents on Trials 51-60. Independent t tests indicated a significant difference between the two groups for both Speed Error and Error Detection. Examination of individual scores of the adolescents with CP indicated that half scored within the range of the control group, and variability of skills within the group with CP was high. Some individuals with CP have deficits in accuracy of movement speed and error detection unrelated to their severity of CP which may affect their ability to learn new movements.     

Virtual navigation performance: the relationship to field of view and prior video gaming experience

Two experiments examined whether learning a virtual environment was influenced by field of view and how it related to prior video gaming experience. In the first experiment, participants (42 men, 39 women; M age = 19.5 yr., SD = 1.8) performed worse on a spatial orientation task displayed with a narrow field of view in comparison to medium and wide field-of-view displays. Counter to initial hypotheses, wide field-of-view displays did not improve performance over medium displays, and this was replicated in a second experiment (30 men, 30 women; M age = 20.4 yr., SD = 1.9) presenting a more complex learning environment. Self-reported video gaming experience correlated with several spatial tasks: virtual environment pointing and tests of Judgment of Line Angle and Position, mental rotation, and Useful Field of View (with correlations between .31 and .45). When prior video gaming experience was included as a covariate, sex differences in spatial tasks disappeared.     

Visual search strategies of baseball batters: eye movements during the preparatory phase of batting

The aim of this study was to analyze visual search strategies of baseball batters during the viewing period of the pitcher's motion. The 18 subjects were 9 experts and 9 novices. While subjects viewed a videotape which, from a right-handed batter's perspective, showed a pitcher throwing a series of 10 types of pitches, their eye movements were measured and analyzed. Novices moved their eyes faster than experts, and the distribution area of viewing points was also wider than that of the experts. The viewing duration of experts of the pitching arm was longer than those of novices during the last two pitching phases. These results indicate that experts set their visual pivot on the pitcher's elbow and used peripheral vision properties to evaluate the pitcher's motion and the ball trajectory.     

Associations on dimensions of burnout and family support for a sample of Greek nurses

To assess correlations for perceived family support with burnout in Greek nurses, the Julkunen Family Support Questionnaire and the Maslach Burnout Inventory were administered to nurses (22 men and 88 women; M age = 35.6 yr., SD = 5.7 yr.; M work experience = 12.2 yr., SD = 6.2 yr.). The correlation was positive but low for family support and sense of personal accomplishment by women; all the other correlations were low, accounting for very small variance.     

Anxiety and depression in Greek nursing and medical personnel

The relatively low number of nurses compared to physicians in Greece and the few available studies on the psychological problems of the health professionals led to comparison of anxiety and depression for 76 Greek nursing personnel (20 men, M age: 32.8 yr., SD: 3.8 yr., and 56 women, M age: 36.6 yr., SD: 7.7 yr.) and 66 doctors (35 men, M age: 35.9 yr., SD: 8.9 yr. and 31 women, M age: 32.7 yr., SD: 8.1 yr.) using validated translations of the Spielberger State-Trait Anxiety Inventory and the Beck Depression Inventory. Male nurses had the lowest scores on trait anxiety, while female doctors had the highest scores, followed by female nurses. Depression scores were not different between doctors and nurses, regardless of sex. Age and depression scores were positively correlated (Spearman rho = .31) only for the female nurses. The findings suggest that interventions for diagnosis and stress management in the health-care workplace should be equally targeted for nursing and medical personnel.     

Cooperative learning in third graders' jigsaw groups for mathematics and science with and without questioning training

Background. There is much support for using cooperative methods, since important instructional aspects, such as elaboration of new information, can easily be realized by methods like ‘jigsaw’. However, the impact of providing students with additional help like a questioning training and potential limitations of the method concerning the (minimum) age of the students have rarely been investigated. Aims. The study investigated the effects of cooperative methods at elementary school level. Three conditions of instruction were compared: jigsaw, jigsaw with a supplementary questioning training and teacher‐guided instruction. Sample. Nine third grade classes from three schools with 208 students participated in the study. In each school, all the three instructional conditions were realized in three different classes. Method. All classes studied three units on geometry and one unit on astronomy using the assigned instructional method. Each learning unit comprised six lessons. For each unit, an achievement test was administered as pre‐test, post‐test and delayed test. Results. In the math units, no differences between the three conditions could be detected. In the astronomy unit, students benefited more from teacher‐guided instruction. Differential analyses revealed that ‘experts’ learned more than students in teacher‐guided instruction, whereas ‘novices’ were outperformed by the students in the control classes. Conclusions. Even third graders used the jigsaw method with satisfactory learning results. The modest impact of the questioning training and the low learning gains of the cooperative classes in the astronomy unit as well as high discrepancies between learning outcomes of experts and novices show that explicit instruction of explaining skills in combination with well‐structured material are key issues in using the jigsaw method with younger students.     

Alteration of adults' subjective feeling of familiarity toward infants' sounds

Many adults may have lower subjective feelings of familiarity toward infants' vocalizations since infants' sounds are different from those of adults. However, mothers frequently exposed to infants' vocalizations may be more familiar and less averse. To test this hypothesis, 21 mothers (M age = 31.1 yr., SD = 4.3) of infants (M age = 8.2 mo., SD = 3.5), 18 mothers (M age = 34.4 yr., SD = 4.8) of children between two and five years of age (M age = 2.8 yr., SD = 1.0), and 17 women (M age = 29.2 yr., SD = ll.1) with no children were exposed to 20 types of sounds. Of these sounds, 14 were produced by infants. Although the mothers of infants did not recognize sounds as those of an infant's vocalization, they showed higher subjective feelings of familiarity toward the timbres of the vowel-like stimuli than did the other groups. By contrast, the subjective feelings of familiarity for nonspeech sounds did not differ among groups. Maternal experiences may change women's recognition of perceived sounds.     

TEACHING NAMING OF COIN VALUES—COMPREHENSION BEFORE PRODUCTION VERSUS PRODUCTION ALONE1

The purposes of this experiment were to determine whether (a) it would require fewer trials to teach verbal production of coin values directly or to teach auditory comprehension first, (b) comprehension training would generalize or transfer to production, and (c) production training would generalize to comprehension. Fourteen mentally retarded subjects participated. Their mean mental age was 4.83 yr (SD = 1.83), their mean chronological age was 12.67 yr (SD = 3.17), their mean IQ was 43.86 (SD = 7.81), and their mean arithmetic grade level was Kindergarten 0.1. A matched groups pretest-posttest design, as well as a multiple baseline across responses within each group were employed. The Comprehension-Production Group received coin-value training using two procedures sequentially: auditory comprehension (pointing to the correct coins in response to their verbally stated value) followed by verbal production (verbally stating the coins' value in response to a pointing prompt). The Production Group was trained on the production procedure only. Each subject was repeatedly administered coin-value comprehension and coin-value production tests, which provided the dependent measures. The results indicated that the two experimental groups improved significantly in their comprehension and production of coin values from pretest to posttest and maintained those increments on one- and four-week followup tests. Mean group performance on four-week followups ranged from 89 to 96% correct for the two dependent measures and two groups. Multiple-baseline data showed pronounced increases in performance only after training was initiated on a particular coin. A comparison of the number of trials required for both groups to complete their respective training programs indicated that teaching production alone (X? trials = 137.42) was significantly more efficient than training both comprehension and production (X? = 281.71). The failure of the comprehension procedure to facilitate production acquisition was evidenced by the fact that the Comprehension-Production Group required as many verbal naming trials to achieve mastery as did the Production Group. On the other hand, there was generalization from production training to comprehension. Subjects in the Production Group who were not trained to point to the coins in response to verbal instruction averaged 99% correct on the comprehension test. Research to this point may suggest an interaction between mental level and direction of transfer. The mentally retarded may experience facilitation from production to comprehension training, and for the nonretarded, the direction of transfer may be the converse.