226,610 research outputs found
Differential item functioning of the Functional Independence Measure in higher performing neurological patients
OBJECTIVE: When comparing outcomes of the Functional Independence Measure (FIM ) between patient groups, item characteristics of the FIM should be consistent across groups. The purpose of this study was to compare item difficulty of the FIM in 3 patient groups with neurological disorders. SUBJECTS: Patients with stroke (n=295), multiple sclerosis (n=150), and traumatic brain injury (n=88). METHODS: FIM scores were administered in each group. The FIM consists of a motor domain (13 items) and a cognitive domain (5 items). Rasch rating scale analysis was performed to investigate differences in item difficulty (differential item functioning) between groups. RESULTS: Answering categories of the FIM items were reduced to 3 (from the original 7) because of disordered thresholds and low answering frequencies. Two items of the motor domain ("bladder" and "bowel") did not fit the Rasch model. For 7 out of the 11 fitting motor items, item difficulties were different between groups (i.e. showed differential item functioning). All cognitive items fitted the Rasch model, and 4 out of 5 cognitive items showed differential item functioning. CONCLUSION: Differential item functioning is present in several items of both the motor and cognitive domain of the FIM. Adjustments for differential item functioning may be required when FIMdata will be compared between groups or will be used in a pooled data analysi
Spatial Organization of the Cytoskeleton enhances Cargo Delivery to Specific Target Areas on the Plasma Membrane of Spherical Cells
Intracellular transport is vital for the proper functioning and survival of a
cell. Cargo (proteins, vesicles, organelles, etc.) is transferred from its
place of creation to its target locations via molecular motor assisted
transport along cytoskeletal filaments. The transport efficiency is strongly
affected by the spatial organization of the cytoskeleton, which constitutes an
inhomogeneous, complex network. In cells with a centrosome microtubules grow
radially from the central microtubule organizing center towards the cell
periphery whereas actin filaments form a dense meshwork, the actin cortex,
underneath the cell membrane with a broad range of orientations. The emerging
ballistic motion along filaments is frequently interrupted due to constricting
intersection nodes or cycles of detachment and reattachment processes in the
crowded cytoplasm. In order to investigate the efficiency of search strategies
established by the cell's specific spatial organization of the cytoskeleton we
formulate a random velocity model with intermittent arrest states. With
extensive computer simulations we analyze the dependence of the mean first
passage times for narrow escape problems on the structural characteristics of
the cytoskeleton, the motor properties and the fraction of time spent in each
state. We find that an inhomogeneous architecture with a small width of the
actin cortex constitutes an efficient intracellular search strategy.Comment: 14 pages, 9 figure
Progression of motor subtypes in Huntington’s disease. a 6-year follow-up study
The objective of this study is to investigate the progression of predominantly choreatic and hypokinetic-rigid signs in Huntington's disease (HD) and their relationship with cognitive and general functioning over time. The motor signs in HD can be divided into predominantly choreatic and hypokinetic-rigid subtypes. It has been reported in cross-sectional studies that predominantly choreatic HD patients perform better on functional and cognitive assessments compared to predominantly hypokinetic-rigid HD patients. The course of these motor subtypes and their clinical profiles has not been investigated longitudinally. A total of 4135 subjects who participated in the European HD Network REGISTRY study were included and classified at baseline as either predominantly choreatic (n = 891), hypokinetic-rigid (n = 916), or mixed-motor (n = 2328), based on a previously used method. The maximum follow-up period was 6 years. The mixed-motor group was not included in the analyses. Linear mixed models were constructed to investigate changes in motor subtypes over time and their relationship with cognitive and functional decline. Over the 6-year follow-up period, the predominantly choreatic group showed a significant decrease in chorea, while hypokinetic-rigid symptoms slightly increased in the hypokinetic-rigid group. On the Total Functional Capacity, Stroop test, and Verbal fluency task the rate of change over time was significantly faster in the predominantly choreatic group, while on all other clinical assessments the decline was comparable for both groups. Our results suggest that choreatic symptoms decrease over time, whereas hypokinetic-rigid symptoms slightly increase in a large cohort of HD patients. Moreover, different motor subtypes can be related to different clinical profiles
Assessment of motor functioning in the preschool period
The assessment of motor functioning in young children has become increasingly important in recent years with the acknowledgement that motor impairment is linked with cognitive, language, social and emotional difficulties. However, there is no one gold standard assessment tool to investigate motor ability in children. The aim of the current paper was to discuss the issues related to the assessment of motor ability in young pre-school children and to provide guidelines on the best approach for motor assessment. The paper discusses the maturational changes in brain development at the preschool level in relation to motor ability. Other issues include sex differences in motor ability at this young age, and evidence for this in relation to sociological versus biological influences. From the previous literature it is unclear what needs to be assessed in relation to motor functioning. Should the focus be underlying motor processes or movement skill assessment? Several key assessment tools are discussed that produce a general measure of motor performance followed by a description of tools that assess specific skills, such as fine and gross motor, ball and graphomotor skills. The paper concludes with recommendations on the best approach in assessing motor function in pre-school children
Early motor trajectories predict motor but not cognitive function in preterm- and term-born adults without pre-existing neurological conditions
Very preterm (VP; 0.05). Motor problems in childhood were homotypically associated with poorer motor competence in adulthood. Similarly, early cognitive problems were homotypically associated with adult cognitive outcomes. Thus, both motor and cognitive function should be assessed in routine follow-up during childhood
It\u2019s a Matter of Mind! Cognitive Functioning Predicts the Athletic Performance in Ultra- Marathon Runners
The present study was aimed at exploring the influence of cognitive processes on performance in ultra-marathon runners, providing an overview of the cognitive aspects that characterize outstanding runners. Thirty runners were administered a battery of computerized tests right before their participation in an ultra-marathon. Then, they were split according to the race rank into two groups (i.e., faster runners and slower runners) and their cognitive performance was compared. Faster runners outperformed slower runners in trials requiring motor inhibition and were more effective at performing two tasks together, successfully suppressing the activation of the information for one of the tasks when was not relevant. Furthermore, slower runners took longer to remember to execute pre-defined actions associated with emotional stimuli when such stimuli were presented. These findings suggest that cognitive factors play a key role in running an ultra-marathon. Indeed, if compared with slower runners, faster runners seem to have a better inhibitory control, showing superior ability not only to inhibit motor response but also to suppress processing of irrelevant information. Their cognitive performance also appears to be less influenced by emotional stimuli. This research opens new directions towards understanding which kinds of cognitive and emotional factors can discriminate talented runners from less outstanding runners
The impact of high frequency repetitive transcranial magnetic stimulation on fine motor function in medication resistant major depression
<b><i>Objectives:</i></b> Although high-frequency repetitive transcranial magnetic stimulation (HF-rTMS) over the left dorsolateral prefrontal cortex (DLPFC) has been reported to improve mood symptoms in major depressive disorder (MDD), research on its impact on psychomotor symptoms is scarce. This study assessed the psychomotor effects of 1 and 10 sessions, respectively, of HF-rTMS over the left DLPFC. <b><i>Methods:</i></b> Ten HF-rTMS sessions were applied in 21 medication-free MDD patients over a 2-week period. At the beginning, one placebo (sham)-controlled rTMS session was also applied in a cross-over, single-blind design. Psychomotor variables were digitally recorded during completion of a Fitts’ task, at baseline, after the first and second real/sham session and at the end point. <b><i>Results:</i></b> The total 10-session treatment period resulted in a decrease of depression severity. One HF-rTMS session resulted in improvements on the Fitts’ task, without a difference between active and sham stimulation, however. No further improvements occurred from session 2 to session 10. <b><i>Conclusions:</i></b> No evidence was provided to link the observed psychomotor improvements to HF-rTMS stimulation, as a practice effect could have impacted the significant psychomotor outcomes.</jats:p
Balancing the demands of two tasks: an investigation of cognitive–motor dual-tasking in relapsing remitting multiple sclerosis
Background: People with relapsing remitting multiple sclerosis (PwRRMS) suffer disproportionate decrements in gait under dual-task conditions, when walking and a cognitive task are combined. There has been much less investigation of the impact of cognitive demands on balance. Objectives: This study investigated whether: (1) PwRRMS show disproportionate decrements in postural stability under dual-task conditions compared to healthy controls, and (2) dual-task decrements are associated with everyday dual-tasking difficulties. The impact of mood, fatigue, and disease severity on dual-tasking was also examined. Methods: A total of 34 PwRRMS and 34 matched controls completed cognitive (digit span) and balance (movement of center of pressure on Biosway on stable and unstable surfaces) tasks under single- and dual-task conditions. Everyday dual-tasking was measured using the Dual-Tasking Questionnaire. Mood was measured by the Hospital Anxiety & Depression Scale. Fatigue was measured via the Modified Fatigue Index Scale. Results: No differences in age, gender, years of education, estimated pre-morbid IQ, or baseline digit span between groups. Compared with controls, PwRRMS showed significantly greater decrement in postural stability under dual-task conditions on an unstable surface (p=.007), but not a stable surface (p=.679). Balance decrement scores were not correlated with everyday dual-tasking difficulties or fatigue. Stable surface balance decrement scores were significantly associated with levels of anxiety (rho=0.527; p=.001) and depression (rho=0.451; p=.007). Conclusions: RRMS causes dual-tasking difficulties, impacting balance under challenging conditions, which may contribute to increased risk of gait difficulties and falls. The relationship between anxiety/depression and dual-task decrement suggests that emotional factors may be contributing to dual-task difficulties
Measurement properties of fine motor scale of Peabody Developmental Motor Scales-Second Edition: A Rasch analysis
Objective:\ud
To investigate the measurement properties (including rating scale performance, unidimensionality, and differential item functioning) of the fine motor scale of the Peabody Developmental Motor Scales-Second Edition in children, by using the Rasch analysis. \ud
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Design:\ud
A total of 419 children (including 342 typically developing children and 77 children with fine motor delays or difficulties) were recruited in Taiwan for this prospective study. Each child was evaluated with the Peabody Developmental Motor Scales-Second Edition that consists of 26-item grasping and 72-item visual-motor integration subtests. Partial credit Rasch analysis was used for all analyses.\ud
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Results:\ud
The Rasch analysis indicated that middle rating category for 19 grasping and 52 visual-motor integration items could be collapsed to allow only dichotomous response categories. Item fit analysis and principal component analysis suggested that the unidimensionality of the grasping and visual-motor integration subtests could be achieved after removal of two grasping and eight visual-motor integration misfitting items. All but 13 items in the composite scale\ud
could form a unidimensional construct of overall fine motor ability. Furthermore, only a few items were found to show differential item functioning across sex (ten items) or fine motor status (seven items). However, significant ceiling effects were found in the Peabody Developmental Motor Scales-Second Edition subtests and composite scale when applied to these typically developing children.\ud
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Conclusions:\ud
Our results suggest grounds for the revision of the Peabody Developmental Motor Scales-Second Edition in a subsequent edition. Simplifying the rating scales and reducing the misfitting items in the subtests and composite scales might result in a unidimensional assessment of children’s fine motor ability. Clinicians and researchers could use the reduced Peabody Developmental Motor Scales-Second Edition as a criterion-referenced outcome measure to document changes; however, further work is needed to reduce the ceiling effects
Binge eating disorder In adolescence: the role of alexithymia and impulsivity
Binge Eating Disorder (BED) is a disorder, recently included in DSM-5, often present in adolescence. Several studies highlight that adolescents with BED had high levels of impulsivity and alexithymia. Even though studies have underlined the importance of these variables, no studies have investigated their role on adolescents’ emotional-behavioral functioning. This study proposes to verify if adolescents affected by BED show higher levels of alexithymia and impulsivity than adolescents without diagnosis, and what is their role on adolescents’ emotional-behavioral functioning. Thanks to the collaboration with clinical centers for eating disorders, a group composed by 60 adolescents diagnosed with BED was paired to a 60 healthy controls. Participants completed validated self-report questionnaires investigating levels of alexithymia, impulsivity and emotional-behavioral functioning. Adolescents diagnosed with BED showed higher scores on alexithymia, impulsivity and maladaptive emotional-behavioral functioning than healthy controls. Moreover, alexithymia had a mediating effect on the relationship between impulsivity and emotional-behavioral functioning. These results show that alexithymia is a key variable influencing the emotional-behavioral functioning of adolescents affected by BED. Further studies are needed to also check other variables that might lead to the onset of BED. On the other hand, our findings can help clinicians suggesting the importance of promoting prevention and treatment polices focused on alexithymia
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