Influence of Additional Ankle Weights on Kinematic Variables of Late Preterm Infants Aged 3–4 Months

The authors analyzed and compared the effect of additional weight on the spatiotemporal parameters of the kicking movement of late preterm and full-term infants. The experiment was divided into 4 conditions: training, baseline, weight, and postweight. In the W condition, a weight of one third the lower limb mass was added to the infant's ankle. During the baseline and postweight conditions, the ankle weight was removed. Late preterm infants do not differ from full-term infants in relation to spatiotemporal variables at 3 and 4 months. However, during the weight condition, the straightness index and the hip-ankle and knee-ankle correlations decreased in the preterm infants at both ages. In contrast, the straightness index increased in the postweight condition compared to the baseline values at both ages.     

Motor Cortex Plasticity in Children With Spastic Cerebral Palsy: A Systematic Review

A review of the literature was performed to answer the following questions: Does motor cortex excitability correlate with motor function? Do motor cortex excitability and cortex activation change after a rehabilitation program that results in improvements in motor outcomes? Can the 10–20 electroencephalography (EEG) system be used to locate the primary motor cortex when employing transcranial direct current stimulation? Is there a bihemispheric imbalance in individuals with cerebral palsy similar to what is observed in stroke survivors? the authors found there is an adaptation in the geometry of motor areas and the cortical representation of movement is variable following a brain lesion. The 10–20 EEG system may not be the best option for locating the primary motor cortex and positioning electrodes for noninvasive brain stimulation in children with cerebral palsy.     

Individual differences in motor development during early childhood: An MEG study

In a previous study, we reported the first measurements of pre‐movement and sensorimotor cortex activity in preschool age children (ages 3–5 years) using a customized pediatric magnetoencephalographic system. Movement‐related activity in the sensorimotor cortex differed from that typically observed in adults, suggesting that maturation of cortical motor networks was still incomplete by late preschool age. Here we compare these earlier results to a group of school age children (ages 6–8 years) including seven children from the original study measured again two years later, and a group of adults (mean age 31.1 years) performing the same task. Differences in movement‐related brain activity were observed both longitudinally within children in which repeated measurements were made, and cross‐sectionally between preschool age children, school age children, and adults. Movement‐related mu (8–12 Hz) and beta (15–30 Hz) oscillations demonstrated linear increases in amplitude and mean frequency with age. In contrast, movement‐evoked gamma synchronization demonstrated a step‐like transition from low (30–50 Hz) to high (70–90 Hz) narrow‐band oscillations, and this occurred at different ages in different children. Notably, pre‐movement activity (‘readiness fields’) observed in adults was absent in even the oldest children. These are the first direct observations of brain activity accompanying motor responses throughout early childhood, confirming that maturation of this activity is still incomplete by mid‐childhood. In addition, individual children demonstrated markedly different developmental trajectories in movement‐related brain activity, suggesting that individual differences need to be taken into account when studying motor development across age groups.     

Oceans of stimuli: an individual-based model to assess the role of olfactory cues and local enhancement in seabirds’ foraging behaviour

Animal Cognition - Oceans are extremely dynamic environments, which poses challenges for top-predators such as seabirds to find food resources. Yet, seabirds evolved sensorial abilities (olfactory...     

The Critical Point to Step into a Hole is Similar in Young and Older Adults

Abstract

The avoidance of a hole in the pathway while walking has been systematically investigated; however, depending on the dimensions of the hole, the option to avoid it is infeasible, and it is necessary to use the so-called accommodation strategy to step into the hole. We investigated the critical point between the avoidance and accommodation strategies when dealing with a hole in the ground during locomotion of young and older adults. Young and older adults performed two tasks: verbal estimation and walking. We used holes of different lengths and constant depth (12?cm). In the verbal estimation task, participants stood and looked at each hole and verbally respond if they would step into or avoid it. In the walking task, they walked and chose to either step or avoid the hole. Both age groups preferred to step into the hole when it was larger than 1.3 times their foot length in both tasks. The perception of affordances of young and older adults to step into a hole was similar, and it was unaffected by the investigated tasks. Thus, our participants preferred to have a safety margin that was large enough to guarantee that the whole foot would accommodate within the hole.     

The relationship between maladaptive personality functioning and problematic technology use in adolescence: A cluster analysis approach

In the last two decades, scientific research has explored the problematic use of internet, videogames and mobile phones. However, there is still little consistent knowledge regarding the co-occurrence of problematic technology use and the role of maladaptive personality characteristics in adolescence. The present study aimed to investigate adolescents' styles of technology use with a cluster analysis approach focusing on personality functioning. The sample comprised 408 Italian adolescents (46.3% males) aged 11 to 18 years (M _age = 13.80; SD = 2.08). Data were collected using the Internet Addiction Test, the Videogame Dependency Scale, the Test of Mobile-Phone Dependence Brief Form and the Personality Inventory for DSM5 Brief Form. Results provided a four-cluster solution based on the co-occurrence of problematic technology use. The four clusters were labeled as follows: cluster 1: “Above average internet and mobile-phone use”; cluster 2: “Below average technology use”; cluster 3: “Above average videogame use”; and cluster 4: “Problematic technology use.” Analyses on demographic variables (e.g., gender and age) demonstrated significant differences between the four groups. Adolescents with high levels of problematic technology use reported greater overall personality dysfunction than the other three groups. This finding supported our hypothesis on maladaptive personality functioning in adolescents at risk for addiction. Finally, the Antagonism domain played a specific role in differentiating the severity of adolescents' involvement in technology use. Further studies are needed to confirm our findings and to plan preventive interventions as well as therapeutic treatments.     

Behavioral reactions of newborns to speech-like sounds and their implications for developmental studies

Newborns exposed to a randomized sound battery containing speech-like sounds demonstrated a variety of behavioral reactions reflecting individual differences in personality and organization. Subjects who actively searched the environment for stimuli and showed prolonged vigilance episodes scored in the 90th percentile on the Denver Developmental Test when evaluated at later ages. Subjects who were remarked as inhibiting crying during their exposure to the experimental schedule later were described by their parents as “good” babies, while subjects who vocalized their displeasure during exposure were described far less favorably. These findings may have implications for developmental studies of mother-infant interactions.     

Effects of inversion and negation on social inferences from faces

Judgments about personality and other social characteristics based on facial appearance are remarkably consistent across individuals. However, whereas the facial cues that underpin age and sex judgments are already well understood, the physical bases for judgments of characteristics such as intelligence or trustworthiness are still unknown. Inversion and photographic negation are used here to investigate the visual processes underlying social inferences from the face and to explore whether various judgments might rely on different perceptual representations. In experiment 1, the perceptions of age, sex, attractiveness, approachability, intelligence, and trustworthiness, but not distinctiveness, were affected by inversion, and all these characteristics were affected by negation. The effects of inversion and negation were independent, suggesting that they impaired the encoding of different types of information. Moreover, an independent manipulation of hue and luminance in experiment 2 showed that the effects of negation were mainly due to the reversal of luminance values. These results are consistent with the view that information about the configuration of features (the processing of which is impaired by inversion) and information about surface properties (the processing of which is impaired by brightness negation) are both used in the perception of social characteristics from faces. In addition, the fact that there was a similar pattern of impairment across most judgments suggests that there is an initial common perceptual representation of the face, from which most characteristics are inferred.     

AIDS‐NGOs and political participation: Brazilian and Canadian experiences

Non‐governmental organizations (AIDS‐NGO) are an instrument of political pressure and assistance, often serving as a life reconstruction aid for people living with HIV/AIDS. In this case study, we analyze data from historical documents, in‐depth interviews, and questionnaires obtained from participants and community agents in two AIDS‐NGOs: one in Canada (NGO‐Ca), and another in Brazil (NGO‐Br). Despite contextual differences, both NGOs are involved in a fight against stigma and discrimination that may aggravate existing social exclusion. Variances in political participation are nevertheless evident. In NGO‐Ca, efforts are directed towards maintaining and consolidating human and social rights. In NGO‐Br, the primary goal is building these. In NGO‐Ca, the participant is part of a structured organization where he or she receives the required supports; the NGO is thus a service provider. Conversely, in NGO‐Br, the participant is both the actor and author of collectively constructed supportive actions. It is hoped that the lessons learned from this limited case study will assist in the strengthening of AIDS‐NGO organization and activity, particularly in the developing world context. Copyright © 2008 John Wiley & Sons, Ltd.