Perceptual and Motor Skills

Published by Ammons Scientific
Online ISSN: 1558-688X
Print ISSN: 0031-5125
Publications
A simple method for performing t tests of the differences between means of independent groups, matched groups, and paired observations is presented and illustrated. The method is especially appropriate where data are collected simultaneously on a large number of dependent variables. Statistical tables are provided which markedly reduce the number of calculations to be performed. The method provides a clearcut way of graphically representing t test data relative to chosen significance levels.
 
not employed under the no-knowledge condition. For both treatments reacciontime increased systematically with time on task, the greatest amount of change occurring under the no-knowledge condition. In addition, reaccion-rime was a decreasing function of length of interstimulus interval. The findings of the no knowledge portion of the forementioned study are atypical in two respects. Whereas the slope of the linear function relating reaction-time (msec.) to task duration (5-min. blocks) was 11.93, those of one earlier (McCormack, 1958) and rwo later srudies (McCormack, 1960; McCormack & Prysiazniuk, 1961) were 5.46, 4.75, and 3.79, respectively. Also atypical was the finding that reaction-time was a decreasing funccion of length of interstimulus interval since, in each of the three other investigations, an invariant relation was reported. Thus the major conclusions of the scudy employing the 10 females as Ss, especially the no-knowledge but probably the knowledge porcion as well, are highly questionable. The presenc experiments were therefore designed with the purpose of re-exploring the effects on reactiontime of knowledge of results of performance. METHOD S's task was to depress a microswitch as fast as possible each time light from a 15-w bulb was seen through an aperture 1/2 in. in diamecer. The duration of the light was 100 msec. and the apermre was placed at a distance of 7 fr. from S. Reaction-time was recorded by a Hunter Klockounter while the duration of the light was conuolled by a silent timer. A second timer enabled E, who was located in an adjacenc room, to determine whether or not S had responded within a 2-sec. period. In the event of a failure to respond the light was presented 'The research reported in this paper was supported by 3 grant-in-aid from the Associate Committee on Experimental Psychology of the National Research Council, Canada (Grant APBT-40).
 
Over 4,000 RTs were collected for one S in a 5-mo. period. A normal distribution was approximated for the particular sensory-motor link studied.
 
Pc1s (continuous pulsations) within the geomagnetic field, whose durations are about 30 minutes but which can reoccur several times nightly, are observed during periods when global geomagnetic activity is very low (less than 10 nT). The hypothesis that these 0.2 to 5 Hz synchronized micropulsations or hydromagnetic emissions might stimulate physical chemical cascades within the brain that precipitate the sudden death in infants was tested by correlational analysis for a two-year period (1960-1961) for Ontario. Results were consistent with the hypothesis that the monthly incidences of these unexpected deaths, pcl micropulsations and geomagnetic activity less than 10 nT displayed a shared source of variance. Implications are discussed.
 
This study investigated stress symptoms before and after the September 11, 2001 terrorist attack on the World Trade Center. Responses to the Smith Stress Symptoms Inventory were compared for Chicago area college students assessed 1 to 5 weeks after 9/11 (n=149) and a comparable sample tested up to 5 months prior to 9/11 (n=320). Post-9/11 participants scored higher on Attention Deficit. Contrary to prior research, post-9/11 participants did not score higher on distress, including Worry, Autonomic Arousal/Anxiety, Striated Muscle Tension, Depression, and Anger. It is suggested that those indirectly exposed to a terrorist attack may display traditional symptoms of distress and arousal (as suggested by previous research). Later symptoms of attention deficit and distancing may emerge. This work was based on independent pre- and post-9/11 samples and must be replicated longitudinally as a test-retest to draw conclusions regarding change over time.
 
This study investigated whether stress symptoms related to attention deficit previously found for a sample (n= 149) of Chicago-area college students 1 to 5 weeks after the September 11th attacks were present in a comparable sample (n = 129) 12 to 14 months later. As hypothesized, the later participants had a significantly lower mean score on the scale, Attention Deficit of the Smith Stress Symptoms Inventory, than a different group of participants tested immediately after the attacks. Mean Attention Deficit scores for groups after one year and immediately before September 11th (n=320) did not differ statistically. Findings are consistent with the interpretation that elevations in scores on Attention Deficit immediately after September 11th were indeed associated with the catastrophic attacks and not artifacts of time of examination. Consistent with previous research with this inventory, disaster-related traumatic stress scores are lower over time, although here no control group was included.
 
In 2000-2001 academic year the frequency distribution of hours slept per night was not significantly different from distributions of 1978-79 and 1988-89.
 
Based on visual inspection of data, reinforcement procedures, namely, use of verbal praise and verbal praise plus token exchange, were at least mildly influential in improving performance of 5 youth with moderate mental retardation compared to their initial performance without reinforcers. These findings suggest specific reinforcement may improve the time for aerobic activity by adolescents with moderate mental retardation.
 
Human equilibrium was measured during exposure to continuous and intermittent 1000-Hz tones presented both asymmetrically (one ear) and symmetrically (both ears). Intermittency combined with asymmetry produced greater decrements in equilibrium than either variable alone. The results are interpreted as a possible demonstration of acoustic stimulation of the vestibular system.
 
Thresholds for pressure pain were tested in 64 adult human subjects (age: M=22.0 yr., SD=7.5). The subjects were young adults drawn from a student population. They were divided into two groups of men and two groups of women, with 16 participants in each group. A female experimenter tested one group of men and a male experimenter tested the other group. The women were tested in a similar way by an experimenter of the same sex for one group and the opposite sex for the other group. The two experimenters were dressed in a manner that emphasised their gender roles. The men tested by a female experimenter showed a higher average pain threshold than the men tested by a male experimenter, but there was no difference in the average pain thresholds of the two groups of women.
 
The odor of 2-heptanone was delivered by a precision olfactometer to five Ss using five methods of single-sample presentation of concentrations: (1) randomized, (2) sequential-down, (3) sequential-up, (4) constant stimulus—10 samples, and (5) constant stimulus—100 samples. Lowest thresholds were obtained with method (3) and the highest threshold resulted from method (2). Large variations in individual sensitivities between Ss were observed, precluding averaging of data in the constant stimulus methods. The latter were not suitable for measuring thresholds. No decrease in sensitivity due to fatigue or adaptation was noted in the 100-sample presentation; however, significant differences were found between the statistical errors of the first and second kind. When two odorous samples were presented concurrently within a series, a larger number of correct responses were obtained than when an air blank preceded the presentation of the odor, suggesting physical and/or psychological carry-over of stimulus. Specific modifications of the constant-stimulus method are discussed.
 
One of the most widely reported developmental deficits associated with autism is difficulty perceiving and expressing emotion appropriately. Brain activation associated with performance on a new task, the Emotional Congruence Task, requires judging affective congruence of facial expression and voice, compared with their sex congruence. Participants in this pilot study were adolescents with normal IQ (n = 5) and autism or without (n = 4) autism. In the emotional congruence condition, as compared to the sex congruence of voice and face, controls had significantly more activation than the Autism group in the orbitofrontal cortex, the superior temporal, parahippocampal, and posterior cingulate gyri and occipital regions. Unlike controls, the Autism group did not have significantly greater prefrontal activation during the emotional congruence condition, but did during the sex congruence condition. Results indicate the Emotional Congruence Task can be used successfully to assess brain activation and behavior associated with integration of auditory and visual information for emotion. While the numbers in the groups are small, the results suggest that brain activity while performing the Emotional Congruence Task differed between adolescents with and without autism in fronto-limbic areas and in the superior temporal region. These findings must be confirmed using larger samples of participants.
 
Does consciousness have a spatial "location" that can be scientifically investigated? Using a novel phenomenological method, when people are encouraged to explore the question introspectively they not only can make sense of the idea of their consciousness being "located," but will readily indicate its exact position inside the head. The method, based on Francisco J. Varela's work, involves a structured interview led by an expert mediator in which preliminary questions are asked of untrained volunteers about the location of objects and body parts, and then they are questioned about the location from which they are experiencing these objects. 83% of volunteers located with confidence a precise position for the I-that-perceives in the temporal area of the head centred midway behind the eyes. The same results were obtained with blind subjects (congenitally or later) and with non-Westerners. The significance of this subjective source of the experience of the location of perception is discussed linking it to neurological correlates of self-referred conscious activities and of conscious awareness in memory. Further investigations are suggested with trained volunteers and with individuals with psychiatric disorders.
 
The purpose of this study was to assess stability of manipulative behavior across time. 29 infants were seen at both 9 and 9.5 mo.; 20 of these infants were seen again at 12 mo. At each visit the infants were presented several objects for familiarization and tested for response to discrepant objects. Each trial was scored for the duration of looking, rotating the object, fingering, mouthing, and banging, the frequency of transferring the object from hand to hand, and the frequency of dropping, throwing and pushing the object away. Analysis of the data yielded moderate to high correlations between 9 and 9.5 mo. for all but one behavior. Correlations between 9 and 12 mo. were in the same range for most of the behaviors. On the test trials, there were fewer significant correlations. When the behaviors were separated into exploratory and nonexploratory categories, there was more stability for the nonexploratory behaviors; summary scores for both were concurrently related to Bayley Mental Development Index at 12 mo., but in opposite directions. The results suggest that there is stability in some manipulative behaviors, and further, that it is useful to conceptualize two types of manipulative behavior.
 
An analysis of the relationship of reading problems to language habits, PMA and the group Bender-Gestalt test was made for 750 children, ages 10 and 11, who represent 90% of all children born on Kauai, Hawaii in 1955. The percentage of reading problems increased from 1 out of 6 children in the above average to 1 out of 2 children in the below-average SES groups. 88% of the children with reading problems came from homes in which Pidgin English was frequently spoken. Children with reading problems had significantly lower mean scores on all PMA scores than successful readers. Factor V predicted reading grade and STEP reading test scores as well as PMA IQ and better than any other PMA factor. The incidence of reading problems increased with error scores on the group Bender-Gestalt test, but the majority of children with reading problems had adequate Bender-Gestalt reproductions. Most poor B-G reproductions were found among children of low and below average intelligence. The addition of the group Bender-Gestalt error score to the PMA IQ or Factor V did not improve the prediction of reading grade or reading test results.
 
Alphabetical listing of 76 references to work in perception in the Psychological Index, No. 11, 1904.
 
Corsi's block-tapping test and WISC-R were given to 1122 children from 11 to 16 years of age. Corsi's raw scores were transformed into standard scores like those for the WISC-R subtests. Reliabilities, standard score equivalents of raw scores, correlations with scores on WISC-R subtests, scales and factor scores are presented. A Principal Factor analysis of intercorrelations for Corsi's test and WISC-R subtests shows a three-factor solution with Corsi's test loading on the Third Factor. Results agree with Wielkiewicz's (1990) hypothesis about the construct underlying WISC-R Third Factor as "executive" and short-term memory processes.
 
This study examined growth rates in running speed and vertical jump among middle school children. 45 boys and 31 girls ages 11-13 years were tested on running speed and vertical jump three times (September, February, and May) during the school year. Hierarchical linear modeling was used to estimate initial status and growth rates for the entire sample (base model) and the association of running and vertical jump with height, weight, and sex (conditional model). Positive overall growth rates were found for both running speed and vertical jump. Increased heightand weight at the time of measurement were not significantly associated with growth rate for running. The growth rate for vertical jump was positively associated with height but unrelated to increased weight. Boys showed steeper growth rates than girls in jumping. No sex differences were found in running speed for either initial status or in growth rate. Furthermore, these results suggest highly variable rates of physical maturation but no general period of 'adolescent awkwardness'.
 
Of 655 neuropsychological referrals who were asked to draw a clock and set the hands at "10 after 11," 9% set the hands at "10 to 11." This low base rate of occurrence suggests the error was not highly sensitive to neurological impairment or diagnostically specific.
 
One issue in the development of narrative comprehension is whether cMdren initially process information at a low level, developing later the ability to build up higher units of organisation (4, 5), or whether they learn first to identify the main ideas of a passage and become increasingly able to subsume less structurally important units under them later in development (1, 3). These approaches may be described as 'bottom-up' and 'top-down' development, respectively. The present study compares the patterns of narrative recall by adults and 11-yr.-old children: taking adults' recall frequencies as an index oE the structural importance of story constituents, top-down development between these ages would predict good over-all agreement on recall frequencies, especially for the more 'important' constituents. Two groups of subjects, 22 children (M age 10.7 yr.; SD: 0.4) and 54 undergraduate students, each received the same 225-word, 30-clause narrative (passage 1A from Cornish, 2), chosen to be equally acceptable to the two age groups. Subjects were read the passage once and asked to write out as much of it as they could remember; they were discouraged from deliberate memorisation. Reproductions were scored for the number of original clauses recalled, after Cornish (2). The mean number of clauses recalled per subject was 17.9 (SD: 4.5) for the children and 23.5 (SD: 4.3) for the students. Recall probabilities were calculated for each clause separately for the two groups. There was a high product-moment correlation between the two sets of omission frequencies (fis = 0.715, p c ,001). However, inspection of the data suggested that the greatest agreement was on the most commonly recalled clauses. This was confirmed by comparing the correlations for the 15 most and 15 least frequently recalled clauses (by the adults' ratings), which were 0.429 (df= 13, p< .05) and 0.339 (df = 13, p = n.s.), respectively. Both the good agreement on the ordering of clauses by recall frequency and the greater agreement on the more frequently recalled clauses support 'top-down' development of narrative comprehension in the 11-yr. to adult age range. The children appear well able to identify structurally important narrative constituents but are less able to comprehend subsidiary material. Future work might look at younger children whose narrative development might proceed in a different manner.
 
An item analysis of Bender-Gestalt error items, as measured by the Koppitz scoring system, was conducted with protocols of 541 children in Grades 2 to 5, selected as being representative of each age level therein, i.e., 7 to 11. The frequencies of each of the 30 possible Koppitz errors at each age level were examined for males, females, and a combined category, in an attempt to identify maturational changes in visual-motor perception. Data from a similarly conducted study with 6-yr.-old first graders are integrated with present findings as many problems in visual perceptual tasks for 6-yr.-olds had been alleviated considerably by age 7. Error items which tend to discriminate over age are identified, as are those items which do not discriminate beyond certain ages. Comparisons by sex were largely nonsignificant.
 
Impulsiveness is increasingly gaining attention as a potential risk factor for various mental disorders. Until now, there have been German instruments that allowed for assessing adolescents' self-reported impulsiveness multi-dimensionally. The present study examined the German version of the Barratt Impulsiveness Scale-11 (BIS-11) for adolescents. The instrument was completed by 659 adolescents ages 10 to 20 years; 98 were retested after 6 months. Items showed adequate psychometric properties. An exploratory factor analysis identified three factors that showed slightdifferences from the initial questionnaire proposed by Barratt. The factors showed low to moderate intercorrelations, satisfactory internal consistency (dependent on factor), and were stable over time. Convergent validity was ascertained, and the item pool showed sufficient power to discriminate adolescents with symptoms of attention deficit hyperactivity disorder and those with loss of eating control from healthy adolescents. Findings suggest that the German BIS-11 is appropriate for reliable investigation of impulsiveness in adolescents. Future research should examine sensitivity as a screening tool, as well as sensitivity to change.
 
The concurrent and content validity of the Rey-Osterrieth Complex Figure Test and the Beery Developmental Test of Visual-Motor Integration-Third Revision were investigated through correlational analysis. 432 children, ages 6 to 11 years, were administered both tests. Across age groups participants performed better on both measures, providing support for the similarity of the measures and their sensitivity to the development of visuomotor integration. Although analysis indicated considerable overlap in the content of the two scales, the shared variance ranged from 7% to 31%, depending on the age of the child. The Rey-Osterrieth figure is composed of overlapping squares, rectangles, triangles, and various other shapes. Given this complex combination, scores on this test reflect the examinees' visual organization and motor planning skills. On the other hand, the Beery test consists of a series of shapes which progress from simple figures to more complex ones. Because the figures become more difficult to copy, the score on this test reflects the examinees' developmental level of visuomotor ability. Despite these differences in test stimuli and interpretation of performance, the present study showed considerable shared variance in the scores of the examinees who took both tests. Finally, local norms for the Rey-Osterrieth figure using the scoring approach of E. M. Taylor (1959, adapted from Osterrieth, 1944) and including standard scores are presented for children ages 6 to 11 years.
 
The purpose of this study was to solicit information about the applicability of 11 basic perceptual concepts for instruction in drawing to students in Kindergarten through Grade 12. The study is based on responses to a national survey of 750 art educators, 250 in elementary, 250 in middle, and 250 in high school teaching assignments. Among these, 87% were female, 8% were 20 to 29 years old, 15% were 30 to 39 years, 48% were 40 to 49 years, 27% were 50 to 59 years, and 2% were 60 years or older. As few as 35.5% to as many as 48.7% (per concept) of the art educators reported that they teach each of the 11 concepts in elementary grades. Also, from 33.3% to 38.4% (per concept) of these teachers indicated that they stop teaching the 11 target concepts to students in high school. Empirical evidence from psychologists suggested that children gain comprehension of the concepts at differing points in their development. Were art educators employing the information identified by psychological research, their reports might have presented clear distinctions between grades at which each of the 11 concepts are taught. The results are interpreted in light of five possible explanations.
 
The purpose of this study was to extend the development of the Italian version of the Barratt Impulsiveness Scale for use with adolescents. The analyses which led to the development of this version were based on data from 563 high school students. The internal consistency was good (Cronbach alpha=.78). A confirmatory factor analysis identified six first-order factors which converged into two second-order factors, a General Impulsiveness factor and a Nonplanning Impulsiveness factor. The General Impulsiveness factor included motor and attention or cognition items. The second-order factors differed from those obtained with the adult Italian version as well as the American version. Possible reasons for these differences are discussed. The new version correlated significantly with self-report measures of aggression and Attention-Deficit/Hyperactivity Disorder as well as with frequency of alcohol use and cigarette smoking.
 
The factorial structure of two tests of cognitive style (the Children's Embedded Figures Test and the Matching Familiar Figures Test-20) and one test of cognitive ability (Raven Progressive Matrices) was examined in this study with a sample of 337 boys and 287 girls between ages 6 and 11 years. Factor I related to Impulsivity and Factor II related to cognitive ability and disembedding skills, which were stable across age groups and sex and accounted for 84.6% of variance.
 
Pediatric clinicians working with school-age children use the Wide Range Assessment of Visual Motor Abilities (WRAVMA) as a method for evaluating visual perception and motor skills in children despite limited information on concurrent validity. Whether it may be substituted for the Beery-Buktenica Developmental Test of Visual-Motor Integration (VMI) and has suitable estimates of concurrent validity were examined with a convenience sample of 91 typically developing children ages 4 to 11 years. No systematic concurrent validity between the WRAVMA and the VMI emerged. Only two subtests of the WRAVMA (Matching with Visual Perception, and Pegboard with Motor Coordination) gave scores statistically significantly correlated with those on the VMI, and these correlations were weak, accounting for very small amounts of the shared variance. As such, they have low clinical relevance. These findings do not provide evidence of concurrent validity to support the use of WRAVMA as an alternative method for the VMI for assessing children's visual perception and motor skills.
 
This study analyzed whether a ball with a higher (540-g) or lower (440-g) mass than the regulation ball (485-g) resulted in a larger number of participants gaining ball possession during games. Prior studies have indicated that ball handling is facilitated by decreasing the mass of the ball. It was assumed that a greater number of children gaining possession of the ball indicated greater ease of use and more control. Thus, the hypothesis was that the number of participants who gained ball possession would increase when using a ball of lower mass. The participants were 54 boys from six youth basketball teams. Participants played four games with each one of the three different balls and the number of possessions was calculated using videos of each game. The hypothesis was only partially supported: the number of participants who gained possession with the regular ball was similar to that with the 440-g ball and with the 540-g ball, but a greater number of participants gained possession with the 440-g ball in comparison to the 540-g ball. This result suggests balls that differ by more than 65 g may affect actual game outcomes.
 
Shooting style in basketball refers to the height adopted by a player in holding the ball, specifically the height of the hand and the ball with regard to the line of sight before the final extension of the elbow during a shot. The literature differentiates between a high and a low style. This study analyzed shooting frequency in young boys as a function of style and which shooting style had the highest accuracy and success in real games. Participants were 81 boys from eight basketball teams, aged 9-11 years. The sample consisted of 5,740 standard shots in 56 games. The design was nomotethic, follow-up, and multidimensional. The results indicated that low style predominated over the high style, although overall accuracy and efficacy were better using the high style. Various strategies and practical considerations are suggested for teachers and coaches to focus on teaching the high style.
 
The goal of the Performance Evaluation Tests for Environmental Research (PETER) Program was to identify a set of measures of human capabilities for use in the study of environmental and other time-course effects. 114 measures studied in the PETER Program were evaluated and categorized into four groups based upon task stability and task definition. The Recommended category contained 30 measures that clearly obtained total stabilization and had an acceptable level of reliability efficiency. The Acceptable-But-Redundant category contained 15 measures. The 37 measures in the Marginal category, which included an inordinate number of slope and other derived measures, usually had desirable features which were outweighed by faults. The 32 measures in the Unacceptable category had either differential instability or weak reliability efficiency. It is our opinion that the 30 measures in the Recommended category should be given first consideration for environmental research applications. Further, it is recommended that information pertaining to preexperimental practice requirements and stabilized reliabilities should be utilized in repeated-measures environmental studies.
 
The current study examined the psychometric properties of the Chinese translation of the Barratt Impulsiveness Scale 11th version in a sample of adolescents from Hunan province, mainland China. During an initial assessment, 396 secondary school students (Grades 10-12) completed the scale and self-report measures assessing problem behaviors and alcohol use. The scale was re-administered 1 mo. later. Analysis gave Cronbach alpha of .80 and test-retest reliability of .70. Confirmatory factor analysis indicated a model containing six first-order factors and two second-order factors best fit the data. Girls reported higher Total scores than boys as well as higher scores on the motor impulsiveness, self-control, and cognitive instability sub-scales. Scores were associated in the predicted direction with a wide variety of self-reported problem behaviors including alcohol use, gambling, and academic misconduct. Current findings indicate that the translated scale is a promising tool with some further development for assessing impulsiveness with Chinese adolescents.
 
Previous research has suggested that the duration of stressful video material is estimated to be longer than one containing less stressful material. The current study sought to examine what effects viewing news coverage of the September 11th 2001 terrorist attacks might have on estimated duration of exposure. 16 participants were recruited from Saint Joseph's College of Maine psychology courses and viewed two 3-min. video clips. One clip contained coverage of the 9-11 terrorist attacks; the other, a nonstressful control, was taken from a familiar segment of The Wizard of Oz. Participants estimated the length of the clip and rated stress experienced while viewing the clip. Analysis showed the September 11th footage was rated as more stressful and was estimated as longer than the control clip.
 
The combined effects of acetazolamide and hypoxia upon several types of visual performance at conditions of low and high illumination were investigated. 2 groups of 18 Ss each received either acetazolamide or placebo tablets and were tested on the same visual measures both at sea level and at a terrestrial elevation of 12,800 ft. The results showed no statistically significant differences between visual performances at low and high elevations regardless of the illumination level. Although acetazolamide combined with hypoxia did not generate any visual anomalies, its effectiveness in reducing visual decrements produced by more severe hypoxia cannot be predicted from the data.
 
Different versions of the Stroop test are used; however, for most versions of the Stroop test, there are no estimations of reliability. In the present study, stimuli were presented singly on a computer screen. 55 Swiss German subjects were tested. Test-retest reliabilities of 'XXXX' strings and conflicting color words were evaluated. Response latencies and Stroop interference were quite reliable. Single-stimulus presentation made it possible also to estimate internal consistency, which was high for classical Stroop interference in this format.
 
Children 4 through 13 yr. of age performed on a haptic-to-visual form-identification task. The obtained curves showed that for both sexes, rate of improvement slowed down at approximately 9 yr. of age.
 
505 kindergarten and primary school children from 4 to 13 years of age were treated for school sports injuries during the period 1990-1997. The incidence of injuries increased statistically significantly from .5 per 1,000 children 4- to 5-yr.-old to 4.8 injured children per 1,000 in 12- to 13-yr.-old. 59% of the injuries involved upper extremities; 35% of these were in the wrist region. 33.5% of the injuries were of the lower extremities, with 50% being of the feet and 36.4% of the ankle. Accidental falls were the main situation (53%) in which school sport accidents occurred. Nearly 65% of these accidental falls occurred at the ground level; the remaining accidents (35%) occurred when the child was working on an apparatus, e.g., parallel bars, balancing beam, side horse. The 4- to 5-yr.-old children were the most vulnerable to accidental fall (67%). A statistically significant increase in injuries in ball sports was observed from 4- to 5-yr.-olds (0%) to the 12- to 13-yr.-olds (28%).
 
74 items from this volume are relevant to perceptual problems.
 
Basic physical fitness was measured using 8 different measures for 10,295 South African children and youths (5,611 boys, 4,684 girls) ages 6 to 13 years. These measurements included height, weight, Body Mass Index, standing long jump, shuttle run, sit-and-reach, sit-up (EUROFIT testing battery), and cricket ball throw scores. Due to the effects of earlier apartheid laws on separating communities, it was hypothesized that scores for different ethnic groups may differ. Therefore, in addition to the calculation of basic norms and sex differences, ethnic differences were also tested. Height and weight, relative to age, were different between the various ethnic groups (Black, White, and Mixed ancestry) for boys, with Black boys being shorter and lighter than White boys. There were no differences in sit-and-reach flexibility scores between the groups. With the exception of the cricket ball throw for girls, White children had higher scores in most tests. Although not significantly different from the White children, in the majority of cases, the children of mixed ancestral origin had scores that ranged between the other two ethnic groups. These results suggest a need for encouraging fitness in school children, and the reintroduction of formal physical education into the South African school curriculum, especially into schools in which Black children predominate.
 
This study was based on data from a longitudinal research program. The cohort consisted of 874 normal children in an entire school grade in a Swedish community. The aim of the study was to investigate the relation between birth weight and behavior at school, for all children and for each sex separately. The results identified specific aspects of behaviour disorder significantly related to low birth weight (LBW) for children at the age of 10 but not at the age of 13. When the sexes were separated, there were no relations between birth weight and deviant behaviour for boys of low birth weight as compared to boys of normal birth weight, while girls of low birth weight showed specific behavioural disorders at age 10 as compared to girls of normal birth weight. For girls reared in families of low parental socioeconomic status, aggressiveness and motor restlessness at age 10 but not at age 13 was also present. Further analyses showed that girls born small-for-gestational age showed lack of school motivation and concentration difficulties both at age 10 and age 13.
 
Taxonomy is an essential prelude to scientific understanding and the heuristic process of hypothesis testing. Some taxonomic work exists for adult suicides (2), but no work on numerical taxonomy with completed suicide in youth can be located. In part this reflects the rarity of youth suicide. But with the dramatic increase in rates in the past decade, enough cases have become available for analysis (4). The present description is based on principal component analysis of 23 demographic and clinical variables identified by the Medical Examiner of Alberta for 130 individuals (16% female) aged 10 to 20 who killed themselves berween 1978 and 1984 (1). Six rotated components of the 23 variables accounted for 53% of total variance. Cluster analysis of six factor scores for each individual using the "newest ne~ghbour" algorithm (3) identified six groups of 10 or more cases, with 19 cases falling into groups with fewer than 10 cases each. A variable typified a group if it had a significantly different prevalence (x2, p< .05) from all remaining cases.
 
The aim of this study was to examine the interrater reliability in the coding of the Defense Mechanism Test for 130 variables on both a variable and a subject level. Parallel with a traditional variable analysis, a multivariate strategy for measurement of interrater reliability, built upon principal component analysis, is presented. The results showed high agreement between judges with an overall interrater reliability coefficient of .98 but indicates the need for elucidation in the coding instructions for nine single variables. It also showed that multivariate modeling methods for handling personality test data are highly resistant to occasional differences on single variables but sensitive to major differences.
 
The ability of black American and black African men to recognize previously seen white male faces was assessed. Relationships between recognition, performance scores and quality of interracial experience were also examined. Black American participants (n = 10) performed significantly better and made fewer false responses than the Nigerian participants (n = 10). Significant positive relationships were found between performance scores and interracial experience. Differential use of cues for discriminating white male faces by both groups was also found.
 
Visuospatial functions were studied in 18 patients with spasmodic torticollis and 18 matched controls. Subjects were examined with respect to their judgement of the subjective vertical, personal and extrapersonal orientation, the discrimination of left and right, the ability to judge angles and distances, and a drawing task. Patients showed marked deficits in extrapersonal orientation and atypical displacement errors to the right when requested to set the subjective vertical. Results were largely independent of the clinical characteristics of the disease. The pattern of results was attributed to a subtle attention deficit underlying complex measures of visuospatial functions. This may reflect a discrete dysfunction of the striatal-frontal circuits at least in a subgroup of patients.
 
Top-cited authors
Swarup Mukherjee
  • National Institute of Education (NIE), Singapore
Jamie Lye
  • National Youth Sports Institute
Antonio Tessitore
  • University of Rome Foro Italico
Corrado Lupo
  • Università degli Studi di Torino
Leonardo de Sousa Fortes
  • Universidade Federal da Paraíba