Brain ; physiology ; Child ; Child Behavior ; physiology ; Child Development ; physiology ; Humans ; Infant ; Motor Activity ; physiology ; Motor Skills Disorders ; diagnosis

Cerebellum is a key structure involved in motor learning and coordination. In animal models, motor skill learning increased the volume of molecular layer and the number of synapses on Purkinje cells in the cerebellar cortex. The aim of this study is to investigate whether the analogous change of cerebellar volume occurs in human population who learn specialized motor skills and practice them intensively for a long time. Magnetic resonance image (MRI)-based cerebellar volumetry was performed in basketball players and matched controls with V-works image software. Total brain volume, absolute and relative cerebellar volumes were compared between two groups. There was no significant group difference in the total brain volume, the absolute and the relative cerebellar volume. Thus we could not detect structural change in the cerebellum of this athlete group in the macroscopic level.
Neuronal Plasticity ; Motor Skills/physiology ; Models, Anatomic ; Male ; Magnetic Resonance Imaging ; Humans ; Cerebellum/*anatomy & histology/physiology ; Basketball/*physiology ; Animals ; Adult

This study was done to evaluate differences in pressure pain threshold, grip strength, manual dexterity and touch pressure threshold in the dominant and non-dominant hands of right- and left-handed subjects, and to compare findings within and between these groups. Thirty-nine right-handed and twenty-one left-handed subjects participated in the study. Pressure pain threshold was assessed using a dolorimeter, grip strength was assessed with a hand-grip dynamometer, manual dexterity was evaluated using the VALPAR Component Work Sample-4 system, and touch pressure threshold was determined using Semmes Weinstein monofilaments. Results for the dominant and non-dominant hands were compared within and between the groups. In the right-handed subjects, the dominant hand was significantly faster with the VALPAR Component Work Sample-4, showed significantly greater grip strength, and had a significantly higher pressure pain threshold than the non-dominant hand. The corresponding results for the two hands were similar in the left-handed subjects. The study revealed asymmetrical manual performance in grip strength, manual dexterity and pressure pain threshold in right-handed subjects, but no such asymme-tries in left-handed subjects.
Adult ; Female ; Hand/innervation/*physiology ; Hand Strength/*physiology ; Humans ; Laterality/*physiology ; Male ; Motor Skills/*physiology ; Pain Threshold/*physiology ; Physical Stimulation ; Touch/*physiology

This study was designed to establish norms of hand function, and to identify developmental characteristics of hand function among the Korean children. 712 elementary school children participated in measurement of grip strength, three kinds of pinch strength, and dexterity. The hand strength of the Korean children appeared to be weaker than that of western children. The grip strength of boys was significantly stronger than that of girls in all ages for both hands. The order of magnitude of three kinds of pinch strength was, in descending order, lateral pinch, palmar pinch and tip pinch for both boys and girls. There was no significant difference of hand function according to the type of hand dominance in boys. However, girls with left hand dominance showed weakness of bilateral grip, right tip pinch, and bilateral lateral pinch strength compared with girls with right hand dominance. In conclusion, this study provided normative data of hand functions including dexterity, and enabled us to identify some developmental characteristics of hand functions for the Korean elementary school children.
Age Factors ; Child ; Comparative Study ; Female ; Hand/*physiology ; *Hand Strength ; Human ; Korea ; Laterality ; Male ; Motor Skills ; Schools ; Sex Factors ; Students

Feedback is an important way of information transmission in motor function output. Movement-related information can be transmitted as proprioceptive, haptic, visual and/or audial information to the central nervous system for control and modification of the temporal and spatial precision of motor output. Here presented is a systematic discussion on the principle, technique and effect for some typical motor function rehabilitation methods such as treatment based on EMG feedback, robot-aided movement therapy, high-level perceptional feedback and motor training effect with 3-D virtual reality environment.
Feedback, Psychological ; Humans ; Motor Activity ; physiology ; Motor Skills Disorders ; etiology ; rehabilitation ; Stroke ; complications ; Stroke Rehabilitation ; Therapy, Computer-Assisted ; User-Computer Interface

OBJECTIVETo explore risk factors and protective factors of sensory integrative dysfunction (SID) among preschool and school children in Beijing, and to identify potential risk factors of SID.

METHODSThree hundred and ten kindergarten children were investigated twice in 1993 and 1999 by "The Child Sensory Integration Check List" and "General Information Questionnaire". A nested case-control study was carried out by single variable and multivariate conditional logistic regression analysis to find out the risk factors of SID.

RESULTSIn the SID incidence group, the risk factors of SID were edema during pregnancy (OR = 7.06), paternal age (OR = 1.28), suffering from diseases before 3 years old (OR = 1.13), while the protective factor was family support network during school age (OR = 0.54). In the SID self-recovery group, the risk factors of SID were suspected attention-deficit hyperactivity disorder (ADHD) among maternal cousins (OR = 3.02), social ethos (OR = 1.69), consistency of parental discipline (OR = 1.45), while the protective factors were living condition and environment for entertainment (OR = 0.37), parental care during school age. In the SID negative group, the risk factors of SID were maternal contracted pelvis (OR = 3.45), less chance in enjoying audio and video entertainment during school age (OR = 1.98), suspected ADHD among paternal cousins (OR = 1.89), consistency of parental discipline (OR = 1.75), suspected ADHD among maternal cousins (OR = 1.48), paternal occupation during school age (OR = 1.19), while the protective factors were family support network (OR = 0.56) and maternal educational background (OR = 0.38) during preschool age.

CONCLUSIONOur data showed that the risk factors of child SID were mainly associated with biological and genetic factors. Psychosocial factors seemed to be the secondary risk factors of SID.

Attention Deficit Disorder with Hyperactivity ; classification ; epidemiology ; physiopathology ; Case-Control Studies ; Child ; Child, Preschool ; China ; epidemiology ; Concept Formation ; Female ; Humans ; Learning Disorders ; diagnosis ; epidemiology ; psychology ; Logistic Models ; Male ; Motor Skills ; physiology ; Problem Solving ; Psychomotor Disorders ; diagnosis ; epidemiology ; psychology ; Risk Factors ; Surveys and Questionnaires ; Verbal Learning