Motor Coordination (motor + coordination)

Distribution by Scientific Domains
Distribution within Medical Sciences


Selected Abstracts


Bilateral coordination and motor sequencing in Brazilian children: preliminary construct validity and reliability analysis

OCCUPATIONAL THERAPY INTERNATIONAL, Issue 2 2009
Ana Amélia Cardoso
Abstract This study examined aspects of reliability and validity of the bilateral coordination and motor sequencing items of the Assessment of Motor Coordination and Dexterity (AMCD) for Brazilian children ages 4, 6 and 8 years old. The AMCD aims to identify children with developmental coordination disorder (DCD). A total of 84 children were evaluated. Among the 35 items piloted, all but one presented interrater reliability above 0.80 and 16 (45.7%) items presented intraclass correlation coefficient over 0.60 for test,retest reliability. Most items were sensitive to age difference and only items involving ball handling exhibited significant gender differences. As a result, this section of the AMCD could be reduced to the 20 items that were found to be reliable and more discriminative for age-related differences. This study advances on the development of the AMCD, but a limitation was the noninclusion of children with DCD. Future research should investigate whether the selected items are useful in differentiating the motor skills of children with and without coordination problems. Copyright © 2009 John Wiley & Sons, Ltd. [source]


Predictors of neurodevelopmental outcome of Malaysian very low birthweight children at 4 years of age

JOURNAL OF PAEDIATRICS AND CHILD HEALTH, Issue 4 2001
LC Ong
Objective: To determine neonatal, early developmental and social risk factors that predict the neurocognitive and behavioural outcome of very low birthweight (VLBW) preschool children at four years of age. Methodology: From a cohort of 151 eligible VLBW survivors born in Kuala Lumpur Maternity Hospital, 116 (76.8%) were prospectively followed up from birth till four years. A standardised neurological examination was performed at one and four years to determine the presence of impairment and cerebral palsy, respectively. Cognitive development was assessed using the Mental Scale of the Bayley Scales of Infant Development (MDI) at one year and the Weschler Preschool and Primary Scale of Intelligence-Revised (WIPPSI-R) at four years. Motor coordination was assessed using the Movement Assessment Battery for Children (Movement-ABC). Mothers completed the Child Behaviour Checklist (CBCL) and Parenting Stress Index (PSI) questionnaires. Logistic and multiple regression analyses were used to determine factors associated with cerebral palsy, IQ scores, Movement-ABC and CBCL scores. Results: Factors associated with cerebral palsy were lower MDI scores at one year (P = 0.001) and late neonatal cranial ultrasound abnormalities (P = 0.036). Minor (P = 0.016) or major impairment (P = 0.003) at one year of age and a low level of paternal education (P = 0.01) were associated with poor motor function on the Movement-ABC scale. Lower levels of maternal education (P < 0.001), impairment at one year (P = 0.002) and late neonatal cranial ultrasound abnormalities (P = 0.039) predicted Full Scale IQ scores. Higher PSI scores (P = 0.001), younger mothers (P = 0.003) and late neonatal cranial ultrasound abnormalities (P = 0.009) were associated with worsened child behaviour scores on the CBCL scale. Conclusion: Social factors and the caregiving environment were important determinants of cognitive and behavioural outcome. Cranial ultrasound abnormalities in the late neonatal period and the developmental status at one year might be useful in identifying high risk infants in need of long-term surveillance. [source]


Anxiolytic and antiemetic activity of Zingiber officinale

PHYTOTHERAPY RESEARCH, Issue 7 2002
S. L. Vishwakarma
Abstract The benzene fraction (BF) of a petroleum ether extract of dried rhizomes of ginger, which contained anticonvulsant principle(s), was screened for anxiolytic and antiemetic activity. Motor coordination was not affected by BF per se, but diazepam-induced motor incoordination was potentiated. Animals treated with BF showed decreased occupancy in the closed arm of the elevated plus maze suggesting the presence of anxiolytic principles in the BF. BF also blocked lithium sulphate-induced conditioned place aversion indicating antiemetic activity. These findings suggest that the fraction (BF) possesses anticonvulsant, anxiolytic and antiemetic activity. Copyright © 2002 John Wiley & Sons, Ltd. [source]


The novel nootropic compound DM232 (UNIFIRAM) ameliorates memory impairment in mice and rats

DRUG DEVELOPMENT RESEARCH, Issue 1 2002
Carla Ghelardini
Abstract The favorable pharmacological profile exhibited by piracetam stimulated the synthesis of related compounds potentially endowed with a higher nootropic potency. The antiamnesic and procognitive activity of DM232 (unifiram), a new compound structurally related to piracetam, was investigated. Mouse passive avoidance and rat Morris water maze and Social learning tests were employed. DM232 (0.001,1 mg kg,1 i.p. , 0.01,0.1 1 mg kg,1 p.o.) prevented amnesia induced by scopolamine (1.5 mg kg,1 i.p.), mecamylamine (20 mg kg,1 i.p.), baclofen (2 mg kg,1 i.p.), and clonidine (0.125 mg kg,1 i.p.). Furthermore, The antiamnesic effect of the investigated compound was comparable to that exerted by well-known nootropic drugs such as piracetam (30,100 mg kg,1 i.p.), aniracetam (100 mg kg,1 p.o.), rolipram (30 mg kg,1 p.o.), and nicotine (5 mg kg,1 i.p). DM232 (0.1 mg kg,1 i.p.) was also able to prevent amnesia induced by scopolamine (0.8 mg kg,1 i.p.) in the rat Morris watermaze test. In the rat social learning test, DM232 (0.1 mg kg,1 i.p.) injected in adults rats reduced the duration of active exploration of the familiar partner in the second session of the test. DM232, similarly to piracetam, reduced the duration of hypnosis induced by pentobarbital. At the highest effective doses, the investigated compound did not impair motor coordination (rota rod test), nor modified spontaneous (Animex). These results indicate DM232 (unifiram) as a novel cognition enhancer, strictly related to piracetam-like compounds, able to ameliorate memory impairment at doses about 1,000 times lower than the most active available nootropic compounds. Drug Dev. Res. 56:23,32, 2002. © 2002 Wiley-Liss, Inc. [source]


GluR3 subunit regulates sleep, breathing and seizure generation

EUROPEAN JOURNAL OF NEUROSCIENCE, Issue 5 2008
Hendrik W. Steenland
Abstract The functional role of GluR3 AMPA (,-amino-3-hydroxy-5-methylisoxazole-4-propionic acid) receptor subunits has remained elusive. In vitro studies of genetic knockout mice have not yielded significant alterations in synaptic communication. However, behavioural approaches utilizing knockout mice have shown that the subunit may be involved in exploration and motor coordination, suggesting that in vivo methodologies may be more forthcoming. We tested the hypothesis that GluR3 subunits are involved in the modulation of neural network activity. We used a freely behaving mouse model to examine the effect of GluR3,/, on field potential recordings of electroencephalogram, vital functions (i.e. breathing and heart rate) and muscle tone across natural sleep and wakefulness states. We found that GluR3,/, mice virtually lack electroencephalographic signatures of NREM sleep (n = 9) as demonstrated by reduction in electroencephalogram power in the low-frequency bands (,1, ,2 and ,). In addition, three of nine GluR3,/, mice expressed seizure activity during wakefulness and sleep, suggesting that deletion of the GluR3 gene may predispose to seizure. GluR3 gene knockout also produced state-dependent respiratory modulation, with a selective reduction in breathing rate during behavioural inactivity. These findings show that GluR3 subunits have diverse neurophysiological impact, modulating oscillatory networks for sleep, breathing and seizure generation. Finally, this is the first study to demonstrate the feasibility of direct diaphragm electromyogram recordings in freely behaving mice. [source]


NMDA receptor subunits GluR,1, GluR,3 and GluR,1 are enriched at the mossy fibre,granule cell synapse in the adult mouse cerebellum

EUROPEAN JOURNAL OF NEUROSCIENCE, Issue 11 2001
Kazuyuki Yamada
Abstract Cerebellar N -methyl- d -aspartate (NMDA) receptors are concentrated in the granular layer and are involved in motor coordination and the induction of long-term potentiation at mossy fibre,granule cell synapses. In the present study, we used immunohistochemistry to examine the distribution of NMDA receptor subunits in the adult mouse cerebellum. We found that appropriate pepsin pretreatment of sections greatly enhanced the sensitivity and specificity of immunohistochemical detection. As a result, intense immunolabelling for GluR,1 (NR2A), GluR,3 (NR2C), and GluR,1 (NR1) all appeared in synaptic glomeruli of the granular layer. Double immunofluorescence showed that these subunits were colocalized in individual synaptic glomeruli. Within the glomerulus, NMDA receptor subunits were located between centrally-located huge mossy fibre terminals and peripherally-located tiny Golgi axon terminals. By immunoelectron microscopy, all three subunits were detected at the postsynaptic junction in granule cell dendrites, forming synapses with mossy fibre terminals. Consistent with the known functional localization, GluR,1, GluR,3, and GluR,1 are, thus, anatomically concentrated at the mossy fibre,granule cell synapse. By contrast, immunohistochemical signals were very low in Purkinje cell somata and dendrites in the molecular layer. The lack of GluR,1 immunolabelling in Purkinje cells was unexpected because the cells express GluR,1 mRNA at high levels and high levels of GluR,1 protein in the molecular layer were revealed by immunoblot. As Purkinje cells are exceptionally lacking GluR, expression, the discrepant result may provide in vivo evidence suggesting the importance of accompanying GluR, subunits in synaptic localization of GluR,1. [source]


Evaluation of simple and complex sensorimotor behaviours in rats with a partial lesion of the dopaminergic nigrostriatal system

EUROPEAN JOURNAL OF NEUROSCIENCE, Issue 1 2000
Pascal Barnéoud
Abstract We have examined the behavioural consequences of a partial unilateral dopaminergic denervation of the rat striatum. This partial lesion was obtained by an intrastriatal 6-hydroxy-dopamine injection (6-OHDA, 20 or 10 ,g divided between two injection sites) and was compared with a unilateral complete lesion resulting from an injection of 6-OHDA (2 × 6 ,g) into the medial forebrain bundle. Quantification of striatal dopamine (DA) and its metabolites, and the immunohistochemical evaluation of the nigrostriatal DA system confirmed the complete and partial lesions. Animals with complete striatal denervation displayed both apomorphine- and amphetamine-induced rotations whereas the partial denervation elicited amphetamine-induced rotations only. However, the rates of amphetamine-induced rotation were not correlated with the size of the lesion. In contrast, the paw-reaching impairments were significantly correlated with the striatal dopaminergic depletion. When evaluated in the staircase test, animals with partial denervation were impaired exclusively for the paw contralateral to the side of the lesion. This motor deficit (50,75%) included all components of the skilled paw use (i.e. attempt, motor coordination and success) and was observed at least 12 weeks after the lesion. However, these animals were able to perform normal stepping adjustments with the impaired paw, indicating that the partial lesion induced a coordination deficit of the paw rather than a deficit of movement initiation. After a complete lesion, stepping adjustments of the contralateral paw were dramatically impaired (by 80%), an akinesia which almost certainly accounted for the great deficit in skilled paw use. The paw-reaching impairments resulting from the partial striatal denervation are proposed as a model of the early symptoms of Parkinson's disease and may be useful for the development of restorative therapies. [source]


Prenatal Development of Interlimb Motor Learning in the Rat Fetus

INFANCY, Issue 3 2008
Scott R. Robinson
The role of sensory feedback in the early ontogeny of motor coordination remains a topic of speculation and debate. On E20 of gestation (the 20th day after conception, 2 days before birth), rat fetuses can alter interlimb coordination after a period of training with an interlimb yoke, which constrains limb movement and promotes synchronized, conjugate movement of the yoked limbs. The aim of this study was to determine how the ability to express this form of motor learning may change during prenatal development. Fetal rats were prepared for in vivo study at 4 ages (E18,21) and tested in a 65-min training-and-testing session examining hind limb motor learning. A significant increase in conjugate hind limb activity was expressed by El9, but not El 8 fetuses, with further increases in conjugate hind limb activity on E20 and E21. These findings suggest substantial development of the ability of fetal rats to modify patterns of interlimb coordination in response to kinesthetic feedback during motor training before birth. [source]


Oxygen resuscitation does not ameliorate neonatal hypoxia/ischemia-induced cerebral edema

JOURNAL OF NEUROSCIENCE RESEARCH, Issue 9 2010
Diana Carolina Ferrari
Abstract Neonatal hypoxia/ischemia (HI) is a common cause of cognitive and behavioral deficits in children with hyperoxia treatment (HHI) being the current therapy for newborn resuscitation. HI induces cerebral edema that is associated with poor neurological outcomes. Our objective was to characterize cerebral edema after HI and determine the consequences of HHI (40% or 100% O2). Dry weight analyses showed cerebral edema 1 to 21 days after HI in the ipsilateral cortex; and 3 to 21 days after HI in the contralateral cortex. Furthermore, HI increased blood-brain barrier (BBB) permeability 1 to 7 days after HI, leading to bilateral cortical vasogenic edema. HHI failed to prevent HI-induced increase in BBB permeability and edema development. At the molecular level, HI increased ipsilateral, but not contralateral, AQP4 cortical levels at 3 and up to 21 days after HI. HHI treatment did not further affect HI-induced changes in AQP4. In addition, we observed developmental increases of AQP4 accompanied by significant reduction in water content and increase permeability of the BBB. Our results suggest that the ipsilateral HI-induced increase in AQP4 may be beneficial and that its absence in the contralateral cortex may account for edema formation after HI. Finally, we showed that HI induced impaired motor coordination 21 days after the insult and HHI did not ameliorate this behavioral outcome. We conclude that HHI treatment is effective as a resuscitating therapy, but does not ameliorate HI-induced cerebral edema and impaired motor coordination. © 2010 Wiley-Liss, Inc. [source]


Inhibition of the Activity of Excitatory Amino Acid Transporter 4 Expressed in Xenopus Oocytes After Chronic Exposure to Ethanol

ALCOHOLISM, Issue 7 2008
Seung-Yeon Yoo
Background:, The extracellular glutamate concentration is tightly controlled by excitatory amino acid transporters (EAATs). EAAT4 is the predominant EAAT in the cerebellar Purkinje cells. Purkinje cells play a critical role in motor coordination and may be an important target for ethanol to cause motor impairments. We designed this study to determine the effects of chronic ethanol exposure on the activity of EAAT4 and evaluate the involvement of protein kinase C (PKC) and phosphatidylinositol 3-kinase (PI3K) in these effects. Methods:, EAAT4 was expressed in Xenopus oocytes following injection of EAAT4 mRNA. Oocytes were incubated with ethanol-containing solution for 24 to 96 hours. Membrane currents induced by l -aspartate were recorded using 2-electrode voltage clamps. Responses were quantified by integration of the current trace and reported in microCoulombs (,C). Results:, Ethanol dose- and time-dependently reduced EAAT4 activity. EAAT4 activity after a 96-hour exposure was significantly decreased compared to the control values at all concentrations tested (10 to 100 mM). Ethanol (50 mM) significantly decreased the Vmax (2.2 ± 0.2 ,C for control vs. 1.6 ± 0.2 ,C for ethanol, n = 18, p < 0.05) of EAAT4 for l -aspartate. Preincubation of ethanol-treated (50 mM for 96 hours) oocytes with phorbol-12-myrisate-13-acetate (100 nM for 10 minutes) abolished the ethanol-induced decrease in EAAT4 activity. While staurosporine (2 ,M for 1 hour) or chelerythrine (100 ,M for 1 hour) significantly decreased EAAT4 activity, no difference was observed in EAAT4 activity among the staurosporine, ethanol, or ethanol plus staurosporine groups. Similarly, EAAT4 activity did not differ among the chelerythrine, ethanol, or ethanol plus chelerythrine groups. Pretreatment of the oocytes with wortmannin (1 ,M for 1 hour) also significantly decreased EAAT4 activity. However, no difference was observed in the wortmannin, ethanol, or ethanol plus wortmannin groups. Conclusions:, The results of this study suggest that chronic ethanol exposure decreases EAAT4 activity and that PKC and PI3K may be involved in these effects. These effects of ethanol on EAAT4 may cause an increase in peri-Purkinje cellular glutamate concentration, and may be involved in cerebellar dysfunction and motor impairment after chronic ethanol ingestion. [source]


Ethanol-induced elevation of 3,-hydroxy-5,-pregnan-20-one does not modulate motor incoordination in rats

ALCOHOLISM, Issue 8 2004
Rahul T. Khisti
Background: Ethanol administration elevates the levels of GABAergic neuroactive steroids in brain and contributes to some of its behavioral actions. In the present study, we investigated whether such elevation of GABAergic neuroactive steroids contributes to the motor incoordinating effects of ethanol. Methods: Sprague-Dawley rats were administered ethanol (2 g/kg intraperitoneally) or saline, and the level of 3,-hydroxy-5,-pregnan-20-one (3,,5,-THP) was measured across time in cerebral cortex and in various brain regions at the peak time by radioimmunoassay. To study whether increases in GABAergic neuroactive steroids are responsible for the motor incoordinating actions of ethanol, rats were subjected to chemical (5,-reductase inhibitor, finasteride) and surgical (adrenalectomy) manipulations before receiving ethanol (2 g/kg intraperitoneally) injections. The rats were then subjected to different paradigms to evaluate motor impairment including the Majchrowicz motor intoxication rating scale, Rotarod test, and aerial righting reflex task at different time points. Results: The radioimmunoassay of 3,,5,-THP in different brain regions showed that ethanol increases 3,,5,-THP levels by 3- and 9-fold in cerebral cortex and hippocampus, respectively. There was no change in 3,,5,-THP levels in cerebellum and midbrain. The time course of 3,,5,-THP elevations in the cerebral cortex showed significant increases 20-min after ethanol injection with a peak at 60 min. In contrast, motor toxicity peaked between 5 and 10 min after ethanol injections and gradually decreased over time. Furthermore, adrenalectomy or pretreatment with finasteride (2 × 50 mg/kg, subcutaneously) did not reduce motor incoordinating effects of ethanol as assessed by the Majchrowicz intoxication rating score, Rotarod test, or aerial righting reflex task. Conclusions: Ethanol increases GABAergic neuroactive steroids in a time- and brain region-selective manner. The role of neuroactive steroids in alcohol action is specific for certain behaviors. Alcohol-induced deficits in motor coordination are not mediated by elevated neuroactive steroid biosynthesis. [source]


Different Sensitivity to Ethanol in Alcohol-Preferring sP and -Nonpreferring sNP Rats

ALCOHOLISM, Issue 11 2000
Giancarlo Colombo
Background and Objectives Clinical research has proposed that initial sensitivity to ethanol may be negatively correlated with levels of subsequent ethanol intake; consistently, alcohol-preferring P rats were found to be less sensitive to the ataxic and sedative/hypnotic effects of ethanol than -nonpreferring NP rats. The present study investigated the initial sensitivity to the ataxic and sedative/hypnotic effects of ethanol and to the sedative/hypnotic effects of pentobarbital and diazepam in selectively bred Sardinian alcohol-preferring sP and -nonpreferring sNP rats. Methods: In experiment 1, time to lose (onset) and regain (sleep time) the righting reflex after the acute intraperitoneal (ip) administration of 3.0 and 3.5 g/kg ethanol were measured in sP and sNP rats. In experiment 2, sP and sNP rats were required to perform a motor coordination task on a Rota-Rod after the acute intragastric administration of 2.0, 2.5, and 3.0 g/kg ethanol. Experiment 3 assessed onset and sleep time in sP and sNP rats after the acute injection of pentobarbital (40 mg/kg; ip) and diazepam (15 and 20 mg/kg; ip). Results: In experiment 1, sP rats took shorter times to lose the righting reflex and regained this reflex over longer periods of time and at lower blood ethanol levels than sNP rats. In experiment 2, ethanol affected motor coordination to a greater extent in sP than sNP rats. In contrast, results from experiment 3 showed that sP and sNP rats were not differentially sensitive to the sedative/hypnotic effects of pentobarbital and diazepam. Conclusions: The results of experiments 1 and 2 suggest that sP rats possess a genetically determined, greater sensitivity to the motor impairing and sedative/hypnotic effects of ethanol than sNP rats. Although caution should be adopted before hypothesizing any comparison to humans, these results may feature sP rats as an experimental model of those subsets of human alcoholics with initial high sensitivity to ethanol challenges. Finally, the results of experiment 3 suggest a minimal involvement of the benzodiazepine and barbiturate recognition sites in the differential sensitivity to ethanol of sP and sNP rats. [source]


Riluzole prolongs survival time and alters nuclear inclusion formation in a transgenic mouse model of Huntington's disease

MOVEMENT DISORDERS, Issue 4 2002
Johannes Schiefer MD
Abstract Glutamate excitotoxicity has been suggested to contribute to the pathogenesis of Huntington's disease (HD). Riluzole is a substance with glutamate antagonistic properties that is used for neuroprotective treatment in amyotrophic lateral sclerosis and which is currently tested in clinical trials for treatment of HD. R6/2 transgenic mice, which express exon 1 of the human HD gene with an expanded CAG triplet repeat, serve as a well-characterized mouse model for HD with progressing neurological abnormalities and limited survival. We treated R6/2 HD transgenic mice with riluzole orally beginning at a presymptomatic stage until death to investigate its potential neuroprotective effects in this mouse model and found that survival time in the riluzole group was significantly increased in comparison to placebo-treated transgenic controls. Additionally, the progressive weight loss was delayed and significantly reduced by riluzole treatment; behavioral testing of motor coordination and spontaneous locomotor activity, however, showed no statistically significant differences. We also examined the formation of the HD characteristic neuronal intranuclear inclusions (NII) immunohistologically. At a late disease stage, striatal NII from riluzole-treated transgenic mice showed profound changes in ubiquitination, i.e., NII were less ubiquitinated and surrounded by ubiquitinated micro-aggregates. Staining with antibodies directed against the mutated huntingtin revealed no significant difference in this component of NII. Taken together, these data suggest that riluzole is a promising candidate for neuroprotective treatment in human HD. © 2002 Movement Disorder Society [source]


Clinical neurological abnormalities in young adults with Asperger syndrome

PSYCHIATRY AND CLINICAL NEUROSCIENCES, Issue 2 2006
PEKKA TANI md
Abstract, Children with Asperger syndrome (AS), a neurodevelopmental disorder falling in the autism spectrum disorders, have an increased rate of neurological abnormalities, especially in motor coordination. While AS is a lifelong condition, little is known about the persistence of neurological abnormalities in adulthood. Twenty young adults with AS were compared with 10 healthy controls using a structured clinical neurological rating scale. The score for neurological abnormalities was higher in the AS group. In addition, a subscore for neurological soft signs indicating defective functioning of the central nervous system with a non-localizing value was significantly higher in the AS subjects. This preliminary study indicates that neurological abnormalities, soft signs in particular, represent a non-specific vulnerability factor for AS. Consistent with other features of AS, neurological abnormalities seem to persist into adulthood. [source]


Acute hyperglycemia produces transient improvement in glucose transporter type 1 deficiency

ANNALS OF NEUROLOGY, Issue 1 2010
Cigdem I. Akman MD
Objective Glucose transporter type 1 deficiency syndrome (Glut1-DS) is characterized clinically by acquired microcephaly, infantile-onset seizures, psychomotor retardation, choreoathetosis, dystonia, and ataxia. The laboratory signature is hypoglycorrhachia. The 5-hour oral glucose tolerance test (OGTT) was performed to assess cerebral function and systemic carbohydrate homeostasis during acute hyperglycemia, in the knowledge that GLUT1 is constitutively expressed ubiquitously and upregulated in the brain. Methods Thirteen Glut1-DS patients completed a 5-hour OGTT. Six patients had prolonged electroencephalographic (EEG)/video monitoring, 10 patients had plasma glucose and serum insulin measurements, and 5 patients had repeated measures of attention, memory, fine motor coordination, and well-being. All patients had a full neuropsychological battery prior to OGTT. Results The glycemic profile and insulin response during the OGTT were normal. Following the glucose load, transient improvement of clinical seizures and EEG findings were observed, with the most significant improvement beginning within the first 30 minutes and continuing for 180 minutes. Thereafter, clinical seizures returned, and EEG findings worsened. Additionally, transient improvement in attention, fine motor coordination, and reported well-being were observed without any change in memory performance. Interpretation This study documents transient neurological improvement in Glut1-DS patients following acute hyperglycemia, associated with improved fine motor coordination and attention. Also, systemic carbohydrate homeostasis was normal, despite GLUT1 haploinsufficiency, confirming the specific role of GLUT1 as the transporter of metabolic fuel across the blood-brain barrier. The transient improvement in brain function underscores the rate-limiting role of glucose transport and the critical minute-to-minute dependence of cerebral function on fuel availability for energy metabolism. ANN NEUROL 2010;67:31,40 [source]


Neurocognitive function in patients with small cell lung cancer,

CANCER, Issue 3 2008
Effect of prophylactic cranial irradiation
Abstract BACKGROUND. The use of prophylactic cranial irradiation (PCI) in patients with small cell lung cancer (SCLC) has been tempered by fears of detrimental effects on cognitive function. Neuropsychologic testing was prospectively conducted before and after PCI to evaluate its effects on cognitive function in patients with SCLC. METHODS. Ninety-six patients who completely or partially responded to initial therapy underwent formal neurocognitive testing before PCI. Three patients who had central nervous system metastasis were excluded. Of the remaining patients, 69 received PCI (mean dose, 25 grays [Gy] in 10 fractions). Repeat testing was performed on 37 patients (median follow-up, 23 months; range, 6,120 months). RESULTS. Baseline impairment was defined as ,1.5 standard deviations below the normative mean. Before undergoing PCI, 47% of patients had evidence of impaired cognitive function. After PCI, univariate analysis revealed significant transient declines in executive function (pre-PCI mean, 15.6 ± 11.5; post-PCI, 27.1 ± 17.6 [P = .008]) and language (pre-PCI mean, 33.8 ± 9.9; post-PCI, 31.0 ± 9.0 [P = .049]) at early timepoints. Controlling for noncentral nervous system disease progression the deficit in executive function was no longer significant. Moreover, these deficits were not sustained, and significant improvements in language and motor coordination were recorded. On multivariate analysis, no significant differences before and after PCI were found. CONCLUSIONS. Neurocognitive testing demonstrated that a substantial portion of patients with SCLC had impaired brain functioning at baseline. Persistent declines in cognitive function were not observed after cranial irradiation. These data do not favor the omission of PCI on the basis of fears of neurotoxic effects. Cancer 2008. © 2007 American Cancer Society. [source]


Working memory: Its role in dyslexia and other specific learning difficulties

DYSLEXIA, Issue 3 2004
Sharman Jeffries
Abstract This paper reports a study contrasting dyslexic children against a control group of children without special educational needs (SEN) and a group with varied SENs. Children's abilities were compared on tasks assessing phonological processing, visuo-spatial/motor coordination and executive/inhibitory functioning; being targeted for assessment based on theoretical proposals related to the working memory model. Primary and secondary school level children were tested: 21 assessed as dyslexic with no comorbid difficulties, 26 children assessed with difficulties including dyspraxia, emotional/behavioural problems and attention deficits, 40 children with no known education-related deficits were controls. Results indicated both SEN groups performed worse than controls on working memory phonological loop measures. However, SEN groups could only be differentiated on phonological awareness measures: the dyslexics showing lower scores. Dyslexics performed as well as controls on working memory visuo-spatial scratch pad measures and one of two additional visual,motor coordination tasks, whereas the performance of the other SEN children was lowest on the majority of these measures. Central executive and interference measures engendered mixed performances, both SEN groups showing evidence of deficits in one or more of these areas of functioning, although, of the two SEN groups, the dyslexics seem to have performed the worse when digit name processing was required. Copyright © 2004 John Wiley & Sons, Ltd. [source]