A comparison of cognitive processes and components of neurological maturation in 3-and-11 year-old children

The relationship between the child's cogni tive development and neurological maturation has been of theoretical interest for many year s. Due to diff iculties such as the lack of sophisticated techniques for measur ing neurolog ical changes and a paucity of normative data, few studies exist that have attempted to correlate the two factors. Recent theory on intellectual development has proposed that neurological maturation may be a factor in the increase of short-term memory storage space. Improved technology has allowed reliable recordings of neurolog ical maturation.. In an attempt to correlate cogni tive development and neurological maturation, this study tested 3-and II-year old children. Fine motor and gross motor short-term memory tests were used to index cogni tive development. Somatosensory evoked potentials elici ted by median nerve stimulation were used to measure the time required for the sensation to pass along the nerve to specific points on the somatosensory pathway. Times were recorded for N14, N20, and P22 interpeak latencies. Maturation of the central nervous system (brain and spinal cord) and the peripheral nervous system (outside the brain and spinal cord) was indi~ated by the recorded times. Signif icant developmental di fferences occurred between 3-and ll-year-olds in memory levels, per ipheral conduction velocity and central conduction times. Linear regression analyses showed that as age increased, memory levels increased and central conduction times decreased. Between the ll-year-old groups, there were no significant differences in central or peripheral nervous system maturation between subjects who achieved a 12 plus score on the digit span test of the WISC-R and those who scored 7 or lower on the same test. Levels achieved on the experimental gross and fine motor short-term memory tests differed significantly within the ll-year-old group.

The effect of motor-encoding activities on memory and performance in a grade one reading program

This study examined the effectiveness of motor-encoding activities on memory and performance of students in a Grade One reading program. There were two experiments in the study. Experiment 1 replicated a study by Eli Saltz and David Dixon (1982). The effect of motoric enactment (Le., pretend play) of sentences on memory for the sentences was investigated. Forty Grade One students performed a "memory-for-sentences" technique, devised by Saltz and Dixon. Only the experimental group used motoric enactment of the sentences. Although quantitative findings revealed no significant difference between the mean scores of the experimental group versus the control group, aspects of the experimental design could have affected the results. It was suggested that Saltz and Dixon's study could be replicated again, with more attention given to variables such as population size, nature of the test sentences, subjects' previous educational experience and conditions related to the testing environment. The second experiment was an application of Saltz and Dixon's theory that motoric imagery should facilitate memory for sentences. The intent was to apply this theory to Grade One students' ability to remember words from their reading program. An experimental gym program was developed using kinesthetic activities to reinforce the skills of the classroom reading program. The same subject group was used in Experiment 2. It was hypothesized that the subjects who experienced the experimental gym program would show greater signs of progress in reading ability, as evidenced by their scores on Form G of the Woodcock Reading Mastery Test--Revised. The data from the WRM--R were analyzed with a 3-way split-plot analysis of variance in which group (experimental vs. control) and sex were the between subjects variables and test-time (pre-test vs. post-test) was the within-subjects variable. Findings revealed the following: (a) both groups made substantial gains over time on the visual-auditory learning sub-test and the triple action of group x sex x time also was significant; (b) children in the experimental and control groups performed similarly on both the pre- and post-test of the letter identification test; (c) time was the only significant effect on subjects' performance on the word identification task; (d) work attack scores showed marked improvement in performance over time for both the experimenta+ and control groups; (e) passage comprehension scores indicated an improvement in performance for both groups over time. Similar to Experiment 1, it is suggested that several modifications in the experimental design could produce significant results. These factors are addressed with suggestions for further research in the area of active learning; more specifically, the effect of motor-encoding activities on memory and academic performance of children.

The role of daytime napping in sleepiness and cognitive function in 24-70 year olds /

Daytime napping improves well-being and performance for young adults. The benefits of napping in older adults should be investigated because they have fragmented nocturnal sleep, cognitive declines, and more opportunity to nap. In addition, experience with napping might influence the benefits of napping. Study 1 examined the role of experience with napping in young adults. Habitual (n = 23) and non-habitual nappers (n = 16) were randomly assigned to a 20-minute nap or a 20- minute reading condition. Both groups slept the same according to macro architecture. However, microarchitecture showed greater theta, alpha, and beta power during Stage 1, and greater delta, alpha, and sigma power during Stage 2 for habitual nappers, for the most part indicating better sleep. Both groups felt less sleepy after the nap. P2 latency, reflecting information processing, decreased after the nap for habitual nappers, and after the control condition for non-habitual nappers. In sum, both groups who slept felt better, but only the habitual nappers who napped gained a benefit in terms of information processing. Based on this outcome, experience with napping was investigated in Study 2. Study 2 examined the extent to which daytime napping enhanced cognition in older adults, especially frontal lobe function. Cognitive deficits in older adults may be due to sleep loss and age-related decline in brain functioning. Longer naps were expected to provide greater improvement, particularly for older adults, by reducing sleep pressure. Thirty-two adults, aged 24-70 years, participated in a repeated measures dose-response manipulation of sleep pressure. Twenty- and sixty-minute naps were compared to a no-nap condition in three age groups. Mood, subjective sleepiness, reaction time, working memory, 11 novelty detection, and waking electro physiological measures were taken before and after each condition. EEG was also recorded during each nap or rest condition. Napping reduced subjective sleepiness, improved working memory (serial addition / subtraction task), and improved attention (reduced P2 amplitude). Physiological sleepiness (i.e., waking theta power) increased following the control condition, and decreased after the longer nap. Increased beta power after the short nap, and seen with older adults overall, may have reflected increased mental effort. Older adults had longer latencies and smaller amplitudes for several event-related potential components, and higher beta and gamma power. Following the longer nap, gamma power decreased for older adults, but increased for young adults. Beta and gamma power may represent enhanced alertness or mental effort. In addition, Nl amplitude showed that benefits depend on the preceding nap length as well as age. Since the middle group had smaller Nl amplitudes following the short nap and rest condition, it is possible that they needed a longer nap to maintain alertness. Older adults did not show improvements to Nl amplitude following any condition; they may have needed a nap longer than 60 minutes to gain benefits to attention or early information processing. Sleep characteristics were not related to benefits of napping. Experience with napping was also investigated. Subjective data confirmed habitual nappers were happier to nap, while non-habitual nappers were happier to stay awake, reflecting self-identified napping habits. Non-habitual nappers were sleepier after a nap, and had faster brain activity (i.e., heightened vigilance) at sleep onset. These reasons may explain why non-habitual nappers choose not to nap.

The influence of physical activity behaviour on the relationship between motor proficiency and body composition in children

There is an emerging awareness that children with poor motor abilities are at particular risk for overweight. This cross-sectional study examined the influence of physical activity behaviour on the relationship between motor proficiency and body composition. Participants were 1287 (646 males, 641 females) Grade 6 students in the Physical Health Activity Study project. Height, weight, waist girth, and motor proficiency (Bruininks-Oseretsky Test of Motor Performance BOTMP-SF) were assessed. Physical activity behaviours were also evaluated with a multifaceted approach and reported for school-based, non-school based physical activity, free-time play, and sedentary activities (Participation Questionnaire), and leisure time exercise (Godin-Shephard Leisure Time Exercise Questionnaire GS). Overweight was defined by BMI scores: boys :::20.6-21.2 and <25.1-26.0; girls: ::: 20.7-21.7and <25.4-26.7 and obesity was defined as: boys:::: 25.1-26.0; girls: :::25.4-26.7. Children were classified as case group (CG,::; 10% on BOTMP-SF), borderline case group (BC, > 10% to ::; 20% on BOTMP-SF) or non-case group. Analyses of variance (ANOVAs) uncovered a significant difference in overweight and obesity between the case group and non-case group. Normal-weight children reported higher participation in organized school-sports (intra-mural and inter-school teams). The CG reported significantly lower participation in school sports teams and lower GS results, with a trend towards lower participation in all active pursuits. They also reported a significantly higher duration of television watching and book reading. There were no significant differences between motor proficiency groups by gender, age, nonschool sports, or free-time activity. Multivariate ordinal logistic regression analysis showed that the case group was 10.9 times more likely to be overweight/obese than their peers. No single aspect of physical activity was able to explain the difference in odds ratios for the motor proficiency groups. However, for the entire cohort, children who participated in more organized school sports were less likely to be overweight/obese. These findings confirm that children with low motor proficiency are at significant risk of developing overweight. It is evident that these children have generally attenuated activity levels and heightened levels of sedentary pursuits. School-based activities appear particularly limited, and are the one area where children have near autonomy in their decision to pursue active opportunities. The promotion of school-based programs, specifically intramural sports may be an important aspect in increasing children's overall activity levels. It is also essential to consider the needs of those children with low motor proficiency when designing activity promotion programs. Future research should further explore motor proficiency and overweight/obesity.

Investigating opposing aftereffects in 8-year-olds and adults

Previous studies have shown that adults and 8-year-olds process faces using norm-based coding and that prolonged exposure to one kind of facial distortion (e.g., compressed features) temporarily shifts the prototype, a process called adaptation, making similarly distorted faces appear more attractive (Anzures et aI., 2009; Valentine, 1999; Webster & MacLin, 1999). Aftereffects provide evidence that our prototype is continually updated by experience. When adults are adapted to two face categories (e.g., Caucasian and Chinese; male and female) distorted in opposing directions (e.g., expanded vs. compressed), their attractiveness ratings shift in opposite directions (Bestelmeyer et aI., 2008; Jaquet et aI., 2007), indicating that adults have dissociable prototypes for some face categories. I created a novel meth04 to investigate whether children show opposing aftereffects. Children and adults were adapted to Caucasian and Chinese faces distorted in opposite directions in the context of a computerized storybook. When testing adults to validate my method, I discovered that opposing aftereffects are contingent on how participants categorize faces and that this categorization is dependent on the context in which adapting stimuli are presented. Opposing aftereffects for Caucasian and Chinese faces were evident when the salience of race was exaggerated by presenting faces in the context of racially segregated birthday parties; expanded faces selected as most normal more often for the race of face that was expanded during adaptation than for the race of face that was compressed. However, opposing aftereffects were not evident when members of the two groups were presented engaging in cooperative social interactions at a racially integrated birthday party. Using the storybook that emphasized face race I 11 provide the first evidence that 8-year-olds demonstrate opposing aftereffects for two face categories defined by race, both when judging face normality and when rating attractiveness.

Investigating the association between motor proficiency and body satisfaction in grade 5 children

The inverse relationships between motor proficiency and overweight, and between overweight and body satisfaction have been well documented. However, the association between motor proficiency and body satisfaction has been largely neglected in the literature. Knowledge of the influence that low motor proficiency may have on body satisfaction is essential if the full burden that those children with poor motor abilities face is to be fully recognized, as low body satisfaction has been linked to an increased risk for low self-esteem, depression, and disordered eating. The cohort investigated in this report included 1907 (971 males, 936 female) Grade 5 students from the Physical Health Activity Study Team (PHAST) project in the Niagara Region of Southern Ontario. Children were grouped as overweight or healthy weight (using BMI cut offs for age and gender), and as low motor proficiency or normal motor proficiency (cut-off set at lowest 10% Bruininks Oseretsky Test of Motor Proficiency-short form (BOTMPsf). It was apparent from analyses of variance (ANOVAs) by gender that boys demonstrated significantly higher motor proficiency scores. As a result separate multiple logistic regressions by gender were used to determine the relationship between body satisfaction, BMI, and motor proficiency. There was a significant relationship between BMI and body satisfaction for both genders (p<0.01) and for males a significant relationship between motor proficiency and body satisfaction (p<0.03). Overweight females were less likely to be satisfied with their bodies with an odds ratio (OR) of 0.33 (CI: 0.23-0.47). The same trend was found in overweight males (OR: 0.42, CI: 0.29-0.59). Males with low motor proficiency were significantly less satisfied with their bodies (OR: 0.53, CI: 0.29-0.97). Males with poor motor proficiency were at greater risk for low body satisfaction regardless of their overweight status. Overweight is known to be prevalent among children with low motor proficiency and, these results indicate that low body satisfaction is also a significant concern. These findings confirm that attention needs to be paid to perceptions of body satisfaction among children with low motor proficiency. This is particularly true for boys, as their bodies may fail them in two common societal expectations, shape and skill and for whom their risk of low body satisfaction is heightened by their poor motor proficiency.

Decreased motor unit firing rate in the potentiated tibialis anterior in humans

With repeated activity, force production, rate of force production, and relaxation time are impaired. These are characteristics ofa fatigued muscle (Vandenboom, 2004). However, brief bouts of near maximal to maximal activity results in the increased ability of the muscle to generate force, termed post activation potentiation (P AP)(V andervoort et aI., 1983). The purpose of the present study was to characterize motor unit firing rate (MUFR) in the unfatigued, potentiated tibialis anterior (TA). Using a quadrifilar needle electrode, MUFR was measured during a 5s 50% MVC in which the TA was either potentiated or unpotentiated; monopolar electrodes measured surface parameters. A lOs MVC was used to potentiate the muscle. Firing rate decreased significantly from 20.15±2.9Opps to 18.27±2.99pps, while mean power frequency decreased significantly from 60. 13±7.75 Hz to 53.62±8.56 Hz. No change in root mean square (RMS) was observed. Therefore, in the present study, MUFR decreases in response to a potentiated TA.

Ontological constructivism : Negri and the philosophical foundations of a future communism

As we find in Empire and Multitude, Antonio Negri's political project IS a thoroughly Marxist analysis and critique of global or late capitalism. By modifying and updating Marx's conceptual tools, he is able to provide a clear account of capitalism's processes, its expanding reach, and the revolutionary potential that functions as its motor. By turning to Negri's philosophical works, however, we find that this political analysis is founded on a series of concepts and theoretical positions. This paper attempts to clarify this theoretical foundation, highlighting in particular what I term "ontological constructivism" - Negri's radical reworking of traditional ontology. Opposing the long history of transcendence in epistemology and metaphysics (one that stretches from Plato to Kant), this reworked ontological perspective positions individuals - not god or some other transcendent source - as the primary agents responsible for molding the ontological landscape. Combined with his understanding of kairos (subjective, immeasurable time), ontological constructivism lays the groundwork for opposing transcendence and rethinking contemporary politics.

Effects of age on learning a spatial motor task in younger and older adults individualizing their knowledge of results schedule

Self-controlled KR practice has revealed that providing participants the opportunity to control their KR is superior for motor learning compared to participants replicating the KR schedule of a self-control participant, without the choice (e.g., yoked). The purpose of the present experiment was two-fold. First, to examine the utility of a self-controlled KR schedule for learning a spatial motor task in younger and older adults and second, to determine whether a self-controlled KR schedule facilitates an increased ability to estimate one’s performance in retention and transfer. Twenty younger adults and 20 older adults practiced in either the self-control or yoked condition and were required to push and release a slide along a confined pathway using their non-dominant hand to a target distance. The retention data revealed that as a function of age, a self-controlled KR schedule facilitated superior retention performance and performance estimations in younger adults compared to their yoked counterparts.

Y works : average hours worked and average salaries

Generation Y is entering the workforce in large numbers and, because this generation holds different values than previous generations, accounting firms are having difficulty managing these new hires. I t is important to determine whether Generation Y is associated with meaningful, long-term trends or i f they will adapt to the given situation. Gen Y' s association with average hours worked per person and average salaries in the Canadian Accounting, Marketing, and Legal professions is examined. I find that an increasing percentage of Generation Y employees in the workforce is associated with significant decreases in average hours worked, but is not associated with any significant trend in average salary. I t is concluded that Generation Y is associated with changing trends in the workplace. These trends are contrary to wha t might be expected under traditional definitions of success, therefore it is postulated that Gen Y may view workplace success differently than previous generations.

The development of norm-based coding and category-specific face prototypes : an examination of 5- and 8-year-olds' face space

The present set of experiments was designed to investigate the organization and refmement of young children's face space. Past research has demonstrated that adults encode individual faces in reference to a distinct face prototype that represents the average of all faces ever encountered. The prototype is not a static abstracted norm but rather a malleable face average that is continuously updated by experience (Valentine, 1991); for example, following prolonged viewing of faces with compressed features (a technique referred to as adaptation), adults rate similarly distorted faces as more normal and more attractive (simple attractiveness aftereffects). Recent studies have shown that adults possess category-specific face prototypes (e.g., based on race, sex). After viewing faces from two categories (e.g., Caucasian/Chinese) that are distorted in opposite directions, adults' attractiveness ratings simultaneously shift in opposite directions (opposing aftereffects). The current series of studies used a child-friendly method to examine whether, like adults, 5- and 8-year-old children show evidence for category-contingent opposing aftereffects. Participants were shown a computerized storybook in which Caucasian and Chinese children's faces were distorted in opposite directions (expanded and compressed). Both before and after adaptation (i.e., reading the storybook), participants judged the normality/attractiveness of a small number of expanded, compressed, and undistorted Caucasian and Chinese faces. The method was first validated by testing adults (Experiment I ) and was then refined in order to test 8- (Experiment 2) and 5-yearold (Experiment 4a) children. Five-year-olds (our youngest age group) were also tested in a simple aftereffects paradigm (Experiment 3) and with male and female faces distorted in opposite directions (Experiment 4b). The current research is the first to demonstrate evidence for simple attractiveness aftereffects in children as young as 5, thereby indicating that similar to adults, 5-year-olds utilize norm-based coding. Furthermore, this research provides evidence for racecontingent opposing aftereffects in both 5- and 8-year-olds; however, the opposing aftereffects demonstrated by 5-year-olds were driven largely by simple aftereffects for Caucasian faces. The lack of simple aftereffects for Chinese faces in 5-year-olds may be reflective of young children's limited experience with other-race faces and suggests that children's face space undergoes a period of increasing differentiation over time with respect to race. Lastly, we found no evidence for sex -contingent opposing aftereffects in 5-year-olds, which suggests that young children do not rely on a fully adult-like face space even for highly salient face categories (i.e., male/female) with which they have comparable levels of experience.

Mediating Influence of Physical Fitness on the Relationship between Academic Performance and Motor Proficiency

We explored the potential mediating influence of physical fitness on the relationship between academic performance and motor proficiency in children. 1864 students (F:926, M:938, age 11.91 (SD:0.34). Academic achievement was derived from an average of standardized tests of reading, writing, and math. The Bruininks-Oseretsky Test of Motor Performance (short-form) determined motor proficiency. Fitness (peak oxygen uptake) was established with the Léger 20-m Shuttle Run Test. OLS regression identified several significant predictors of academic performance. After controlling for age (p=0.0135), gender (p<0.0001), and parental education (p<0.0001), motor proficiency (p<0.0001), was significant. After adding physical fitness (p=0.0030) to the model the effect of motor proficiency remained significant however the point estimate was reduced from 0.0034 (p<0.0001) to 0.0026 (p<0.0001). These results suggest that physical fitness plays a mediating role on the relationship between academic performance and motor proficiency although both aerobic fitness and motor proficiency have independent roles.

The influence of emotional body posture on adults' and 8-year-olds' perception facial expressions

The present set of experiments was designed to investigate the development of children's sensitivity of facial expressions observed within emotional contexts. Past research investigating both adults' and children's perception of facial expressions has been limited primarily to the presentation of isolated faces. During daily social interactions, however, facial expressions are encountered within contexts conveying emotions (e.g., background scenes, body postures, gestures). Recently, research has shown that adults' perception of facial expressions is influenced by these contexts. When emotional faces are shown in incongruent contexts (e.g., when an angry face is presented in a context depicting fear) adults' accuracy decreases and their reaction times increase (e.g., Meeren et a1. 2005). To examine the influence of emotional body postures on children's perception of facial expressions, in each of the experiments in the current study adults and 8-year-old children made two-alternative forced choice decisions about facial expressions presented in congruent (e.g., a face displayed sadness on a body displaying sadness) and incongruent (e.g., a face displaying fear on a body displaying sadness) contexts. Consistent with previous studies, a congruency effect (better performance on congruent than incongruent trials) was found for both adults and 8-year-olds when the emotions displayed by the face and body were similar to each other (e.g., fear and sad, Experiment l a ) ; the influence of context was greater for 8-year-olds than adults for these similar expressions. To further investigate why the congruency effect was larger for children than adults in Experiment 1 a, Experiment 1 b was conducted to examine if increased task difficulty would increase the magnitude of adults' congruency effects. Adults were presented with subtle facial and despite successfully increasing task difficulty the magnitude of the. congruency effect did not increase suggesting that the difference between children's and adults' congruency effects in Experiment l a cannot be explained by 8-year-olds finding the task difficult. In contrast, congruency effects were not found when the expressions displayed by the face and body were dissimilar (e.g., sad and happy, see Experiment 2). The results of the current set of studies are examined with respect to the Dimensional theory and the Emotional Seed model and the developmental timeline of children's sensitivity to facial expressions. A secondary aim of the series of studies was to examine one possible mechanism underlying congruency effe cts-holistic processing. To examine the influence of holistic processing, participants completed both aligned trials and misaligned trials in which the faces were detached from the body (designed to disrupt holistic processing). Based on the principles of holistic face processing we predicted that participants would benefit from misalignment of the face and body stimuli on incongruent trials but not on congruent trials. Collectively, our results provide some evidence that both adults and children may process emotional faces and bodies holistically. Consistent with the pattern of results for congruency effects, the magnitude of the effect of misalignment varied with the similarity between emotions. Future research is required to further investigate whether or not facial expressions and emotions conveyed by the body are perceived holistically.

Niagara Falls Taxi Service, N.Y., Scenic motor trips [printed advertisement], ca. 1917.

One pamphlet advertising scenic motor trips conducted by the Niagara Falls Taxi Service, Inc., ca. 1917.