Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “REFLEX, POSTURAL”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 361 records · Page 20Linked to original sources

Implicit learning in Parkinson's disease: evidence from a verbal version of the serial reaction time task.

Evidence suggests that patients suffering from Parkinson's Disease (PD) demonstrate less sequence learning in the serial reaction time (SRT) task devised by Nissen and Bullemer (1987). One of the problems with this task is that it is motor intensive and, given the motor difficulties which characterize Parkinson's disease (e.g., tremor, impaired facility of movement, rigidity, and loss of postural reflexes), allows the possibility that patients with PD are capable of sequence learning but are simply unable to demonstrate this through a decrease in reaction time over trials. The present study examined the performance of patients with PD and healthy controls, matched for verbal fluency, on a verbal version of the SRT task where the standard button-pressing response was replaced by a spoken response. Thirteen nondementing patients with PD and 11 healthy controls were administered the SRT task. The PD group demonstrated less sequence learning than the controls and this was independent of age and severity of illness. The results add support to those studies which have found impaired sequence learning using the standard form of the SRT task.

Adult↗

Hypnosis and spasmodic torticollis--report of four cases: a brief communication.

Dystonia and particularly spasmodic torticollis are neuromuscular disorders that are extremely resistant to most therapies (physical, medical, or surgical). Torticollis is a unilateral spasm of the neck muscles, particularly of the sternocleidomastoid, that produces violent, tonic turning of the head to one side. The etiology remains uncertain, although the role of psychogenic factors has been emphasized. This article reviews the literature and reports four cases of spasmodic torticollis treated successfully with hypnosis. In all four cases, psychogenic causes were involved. Postural hypnosis (i.e., hypnosis in the standing position) was employed to counteract and minimize muscle spasms due to postural reflexes. A hypnobehavioral approach was adopted along with hypnotic strategies that included hierarchical desensitization, sensory-imaging conditioning, ego-boosting suggestions, and hypnosis-facilitated differential muscle retraining. In two cases, a combined hypnosis and electromyographic-biofeedback approach was used to equilibrate and retrain affected neck muscles. Although the hypnotherapeutic process took several months to induce and stabilize significant changes, outcome results were good to excellent in all cases, with marked reduction of the torticollis and the hypertrophy of the neck muscles as well as a reduced interference of symptoms in daily living.

Adult↗

Changes in limb stiffness under conditions of mental stress.

In 2 experiments, the effects of mental stress on limb stiffness were investigated. The relative contribution to arm stiffness of individual muscle activity, co-contraction, muscle reflexes, and postural adjustments were examined. In each experiment, participants (N = 24, Experiment 1; N = 16, Experiment 2) held their supinated hand under a tray that they were required to return to horizontal after it had been suddenly released. Electromyographic activity in the biceps and triceps muscles was recorded, as were elbow and wrist angles and tray displacement. In Experiment 1, mental arithmetic stress was shown to lead to decreased tray displacement (i.e., increased resistance) compared with displacements under the control, unstressed condition, as well as to increased elbow flexion before tray release. In Experiment 2, the increased resistance to perturbation caused by mental stress was found to be independent of initial elbow angle, but to vary as a function of the amount of upward force exerted before tray release. The authors conclude that stress-induced increases in limb stiffness result from changes in the initial position of the elbow, specified by its angle, together with the initial force exerted by participants to counteract the mechanical perturbations.

Adult↗

Moderate hypothermia improves neurobehavioral deficits after an epidural focal mass lesion in rodents.

The objective of this study was to evaluate the effects of a moderate, intraischemic hypothermia on the behavorial deficits up to 4 weeks after induction of a focal mass lesion. A focal epidural mass lesion was induced by an epidural balloon. The severity of the trauma was defined by the balloon volume and flattening of electroencephalography. Hypothermia (32 degrees C) was induced as soon as maximum balloon infIation was reached. Ischemia was extended over 30 min. After reperfusion, normothermic (n = 24) and hypothermic animals (n = 25) were monitored for 3 h followed by a rewarming of the cooled animals. Results were compared to sham-operated animals (n = 10). Behavioral deficits were assessed by postural reflex (PR), open field (OF), beam balance (BB), beam walking (BW), and water maze tests (WMT). MRI follow-up and histology was evaluated. Sham-operated rats showed normal test results. Rats with normothermia showed worsening of test performance (PR, p < 0.05; OF, p < 0.05; BB, p < 0.05; BW, p < 0.05; WMT, p < 0.05) compared to controls over the whole observation period. A significantly better behavioral outcome was observed in animals treated with hypothermia which showed no differences from controls 3-4 days after injury (PR, OF, BB, BW, WMT, p > 0.05). Lesion induced mortality was reduced in cooled animals but overall mortality rates were not influenced by this therapeutic measure. Neuronal cell loss in the CA1-CA4 region (p < 0.05) was reduced and the lesion size smaller (21%/p > 0.05) in hypothermic animals. Magnetic resonance imaging revealed that the lesion was more pronounced in the cortical grey matter after normothermia, whereas hypothermic animals showed more subcortical brain lacerations. In conclusion, intraischemic hypothermia significantly improved the behavioral outcome, and decreased lesion-induced mortality and the size of the lesion after an epidural focal mass lesion.

Animals↗

Dementia and immobility.

Structured physical and psychiatric assessments were performed on 100 elderly women with dementia admitted to either a geriatric or a geriatric psychiatry unit, and the relationship between physical and mental factors and the ability to transfer was investigated. There was an association between limited mobility and physical and psychiatric evidence of cerebrovascular and cardiac disease; but none between mobility and most measures of degree of dementia, vision, hearing, balance, cerebellar function, position sense, ankle reflexes, postural hypotension, locomotor disease, medication or ratings for depression, anxiety, irritability, hostility, lack of co-operation, suspiciousness, or distractibility. This suggests that in dementia the main cause of limited mobility is focal neurological damage.

Aged↗

Impact of Parkinson's disease and its pharmacologic treatment on quality of life and economic outcomes.

The impact of Parkinson's disease (PD) and its pharmacologic treatment on health-related quality of life (HRQL) and economic outcomes is reviewed. PD is a chronic and progressive neurologic disorder characterized by specific motor deficits resulting from the degeneration of dopaminergic neurons in the substantia nigra. The cardinal symptoms are tremor, rigidity, bradykinesia, and loss of postural reflexes. PD markedly reduces HRQL and places an economic burden on society of up to $25 billion per year. Patients' inability to move freely and to perform everyday tasks restricts their independence and leads to increased reliance on caregivers and assistive devices. Emotional and psychosocial well-being is also negatively affected. As the disease progresses, the response to levodopa typically decreases and various motor complications develop; these are difficult to treat and result in further declines in HRQL. The economic costs of PD include both direct health care costs (for drugs, physician services, and hospitalization) and indirect costs (for lost worker productivity). Economic analyses of PD and its treatments can help guide effective allocation of health care resources. Various antiparkinsonian agents and formulations, such as extended-release levodopa-carbidopa and pramipexole, have been found to be cost-effective relative to other agents. The newest antiparkinsonian drugs, cathechol-O-methyltransferase inhibitors, also have the potential to improve HRQL and economic outcomes, although more study is needed to confirm this. The total impact of PD and its treatment can be fully appreciated only when HRQL and economic outcomes, in addition to clinical outcomes, are examined.

Antiparkinson Agents↗

The effects of prenatal alcohol exposure on the behavior of rats during their life span.

Ontogenesis is closely related to the ability to adapt to endogenous and exogenous stimuli. However, this precondition for viability does not remain stable; it changes in correlation to the phases of life. In this long-term study with rats, the extent to which moderate prenatal damage influences the adaptability in the juvenile, adult and senile phases was examined. For this purpose rat fetuses were exposed to alcohol (6 g/kg bw/day) by treating the pregnant rats via drinking water from gestation days 7 to 17. In the juvenile phase (0-3 months), no substantial differences in comparison to controls were recorded. Exceptions were a delayed development in the negative geotaxis (posture reflex) and a transiently higher exploratory activity in the open field test. In the adult phase (> 3-27 months), reduced performance was observed in basic functions such as body temperature regulation. Additionally, diminished performance was seen in response to high demands in motor-coordination (rotorod). During the senile phase (> 27 months), impairment of nearly all tested functions occurred earlier and was more pronounced.

Adaptation, Physiological↗

Early detection of scoliosis. A neurological approach using the asymmetrical tonic neck reflex.

The purpose of this study was to determine the relationship between the asymmetrical tonic neck reflex (ATNR) and the occurrence of scoliosis in healthy children. One hundred eighty-four children, between the ages of 10 years, 5 months to 13 years, 10 months, who attended a rural elementary school were selected for the study. The quadruped reflex-inhibiting posture was used to assess the ATNR. A standard orthopedic screening tool was used for assessment of scoliosis. The occurrence of the ATNR in children tended to increase the rate of referral for further testing for scoliosis. In those children who were assessed for scoliosis using roentgenograms and who had a positive ATNR, a relationship occurred between the convex side of the curvature and the side of the ATNR. Results did not show significant differences in the occurrence of the ATNR or scoliosis in regard to sex. Based on the results of this study, the addition of the ATNR testing to scoliosis screening may prove beneficial in the early identification of scoliosis.

Adolescent↗

Independent sitting development and the emergence of associated motor components.

The purpose of this preliminary study was to examine the relationship between the emergence of independent sitting ability and the presence of underlying motor components (reflexes, automatic postural reactions, and flexion and extension movement patterns). Ten full-term, nonhandicapped infants were tested longitudinally for the presence of underlying motor components as they attained three performance levels of sitting ability between the ages of 4 and 7 months. A total of 26 observations was collected across the 10 infants. The time of each testing session was based on the infants' attainment of each successive sitting performance level. Underlying motor components were assessed at each testing session to determine whether a consistent sequence of component emergence developed and whether those components were associated with a specific performance level of sitting. The results indicated that no consistent sequential pattern of motor component emergence existed. The data showed that the pattern of underlying component emergence was highly variable across the infants at similar levels of sitting ability, although some components were associated highly with specific performance levels. The data suggest that the attainment of independent sitting in nonhandicapped infants is described best as a continuous developmental process, rather than a discontinuous "stage" phenomenon.

Child Development↗

Sensorimotor deficit and cholinergic changes following coexposure with pyridostigmine bromide and sarin in rats.

A myriad of neurological symptoms including muscle and joint pain, ataxia, chronic fatigue, headache, and difficulty in concentration have been reported by Persian Gulf War (PGW) veterans. A large number of these veterans were prophylactically treated with pyridostigmine bromide (PB) and possibly exposed to sarin. In the present study we investigated the effects of PB and sarin, alone and in combination, on sensorimotor performance and the central cholinergic system of rats. Male Sprague-Dawley rats were treated with PB (1.3 mg/kg, 15 daily doses, oral) and sarin (50, 75, 90, and 100 microg/kg, single im dose on day 15), alone and in combination. The animals were evaluated for postural reflexes, limb placing, orienting to vibrissae touch, incline plane performance, beam-walk time, and forepaw grip time 7 and 15 days following treatment with sarin. Treatment with either PB or sarin alone resulted in significant sensorimotor impairments. Coexposure to sarin and PB resulted in significant sensorimotor deficits that worsened over time. By 15 days following sarin treatment, plasma butyrylcholinesterase (BChE) activity returned to normal levels in the animals treated with sarin alone, whereas in the animals exposed to PB or PB plus sarin, there was an increase in the enzyme activity. Cortical acetylcholinesterase (AChE) activity remained inhibited in the animals treated with sarin alone and in combination with PB. Muscarinic acetylcholine receptor (m2 mAChR) ligand binding with [(3)H]AFDX-384 in cortex and brain stem showed significant increases (approximately 120-130% of control) following coexposure to PB and sarin at higher doses. To evaluate the potential of PB for augmentation or inhibition of the toxicity induced by acute sarin exposure, the animals were exposed to either 10 or 100 microg/kg sarin (single im injection) with or without pretreatment with PB, and sacrificed 3 h after treatment with sarin. Pretreatment with PB offered slight protection in the plasma as well as brain regional enzyme activities. Pretreatment with PB did not have any effect on sarin-inhibited brain regional AChE activity following treatment with 100 microg/kg sarin. These results show that prophylactic treatment with PB offers some degree of protection in peripheral cholinesterase. Furthermore, these results show that treatment with either sarin or PB alone resulted in sensorimotor impairments, while coexposure to high doses of sarin with PB caused an exacerbated deficit.

Acetylcholinesterase↗

Pathophysiology of osteoporosis.

As with many chronic diseases that express themselves late in life, osteoporosis is distinctly multifactorial both in etiology and in pathophysiology. Osteoporotic fractures occur because of a combination of injury and intrinsic bony fragility. The injury comes most often from a combination of falls, poor postural reflexes that fail to protect bony parts from impact, and reduced soft tissue padding over bony prominences. The bony fragility itself is a composite of geometry, low mass density, severance of microarchitectural connections in trabecular structures, and accumulated fatigue damage. Reduced bone mass, in turn, is caused by varying combinations of gonadal hormone deficiency, inadequate intakes of calcium and vitamin D, decreased physical activity, comorbidity, and the effects of drugs used to treat various unrelated medical conditions. Finally, the often poor outcome from hip fracture in the elderly is partly caused by associated protein-calorie malnutrition. An adequate preventive program for osteoporotic fracture must address as many of these factors as possible, ie, it must be as multifaceted as the disease is multifactorial.

Age Factors↗

Amelioration of frozen gait by tandospirone, a serotonin 1A agonist, in a patient with pure akinesia developing resistance to L-threo-3,4-dihydroxyphenylserine.

A 71-year-old woman presented with severe akinesia, frozen gait, and compromised postural reflexes, without rigidity, tremor, or vertical gaze disturbance. With a working diagnosis of pure akinesia, we administered amantadine (150 mg/d) and L-threo-3,4-dihydroxyphenylserine (DOPS) (600 mg/d), which alleviated her symptoms. When frozen gait recurred 2 months later, we increased the dose of L-threo-DOPS to 900 mg/d and added levodopa (300 mg/d) combined with carbidopa, but this failed to improve the patient's symptoms. We then combined administration of tandospirone, a serotonin (5-HT) 1A agonist with L-threo-DOPS (600 mg/d), resulting in marked clinical improvement. Tandospirone is reported to activate noradrenergic neurons via the 5-HT 1A receptor, which could account for such striking improvement in a patient previously responsive to the noradrenergic precursor L-threo-DOPS given alone.

Aged↗

A cost-effective, adjustable, femoral socket, temporary prosthesis for immediate rehabilitation of above-knee amputation.

Early ambulation after lower extremity amputation has profound benefits on the functional, psychological outcomes and enhanced prosthetic compliance among this clientele. The various potential risks of immobility--pain, oedema, muscle atrophy, phantom sensations, contractures, aerobic de-conditioning, and the like, are reduced due to early ambulation. Moreover, it assists in accelerated wound healing, preservation of postural reflexes and, above all, achievement of better psychological well-being. Though such benefits have been observed in the history of prosthetic rehabilitation, a cost-effective prosthesis for such an early management among Third World nations is still unavailable. Therefore, this article is an attempt to present an indigenously developed temporary prosthesis designed to make the above benefits possible at a lower cost. This prosthesis helps in myriad ways--immediate prosthetic fitting, early weight bearing, early ambulation--and also has the added advantage of being adjustable to anthropological variations. The ischial weight bearing, lateral opening socket reduces the pressure and shear over the stump, thus avoiding stump complications. This increases the prosthetic acceptance by the client due to early involvement in the rehabilitation. Above all, it is cost effective and comfortable, thus enhancing compliance and superior outcome in prosthetic rehabilitation, especially among the clients in Third World nations.

Amputation, Surgical↗

Delayed treatment with aminoguanidine decreases focal cerebral ischemic damage and enhances neurologic recovery in rats.

Delayed treatment with aminoguanidine (AG), a relatively selective inhibitor of inducible nitric oxide synthase, ameliorates brain damage produced by occlusion of the rat's middle cerebral artery (MCA). We investigated whether the protection exerted by AG is dose-dependent and whether it is associated with improved neurologic outcome. We also studied the effect of the timing of administration of AG relative to the induction of cerebral ischemia. Halothane-anesthetized spontaneously hypertensive rats underwent permanent MCA occlusion distal to the lenticulostriate branches. Neurologic deficits were assessed daily by the postural reflex test and beam balance test. Infarct volume was determined in thionin- stained sections 96 hours after ischemia and values corrected for swelling. Treatment with AG (intraperitoneally, twice daily), starting 24 hours after MCA occlusion, decreased neocortical infarct volume in comparison to vehicle-treated rats. After correction for swelling, the decrease was 8 +/- 12% at 50 mg/kg (n = 8; P > .05; analysis of variance), 25 +/- 13% at 100 mg/kg (n = 7; P < .05), 30 +/- 16% at 200 mg/kg (n = 7; P < .05) and 32 +/- 9% at 400 mg/kg (n = 5; P < .05). Twenty-four hours after induction of ischemia neurologic deficits scores did not differ between treated and untreated rats (P > .05). However, from 48 to 96 hours after ischemia, neurologic deficits improved significantly in rats treated with AG (100 to 400 mg/kg) compared to rats in which vehicle was administered (P < .05). The decrease in neocortical infarct volume was greatest when AG (100 mg/ kg; twice daily) was administered 12 (26 +/- 17%; n = 9) or 24 hours (25 +/- 13, n = 7) after MCA occlusion. The findings show that AG decreases ischemic brain damage dose-dependently and improves neurologic recovery. Delayed treatment with AG may be a therapeutic strategy to selectively target the evolution of ischemic damage that occurs in the post-ischemic period.

Animals↗

The phenotype of the X-linked dystonia-parkinsonism syndrome. An assessment of 42 cases in the Philippines.

The clinical phenotype of X-linked recessive torsion dystonia was documented in 42 affected individuals from 21 families. In 7 families, there were 9 sibships (core families) with 2 or more affected individuals available for evaluation. The ages of the patients ranged from 29 to 79 years with a mean of 46.2 +/- 10.1 years; the mean age of onset of dystonia was 35.0 +/- 8.0 years with a range of 12 to 48 years; and the mean duration of illness was 11.1 +/- 7.9 years. First manifestations were noted in the lower extremities in 36%, the axial musculature in 29%, the upper extremities in 23%, and in the head in 12% of the cases. The majority of patients displayed gait abnormalities (90%), leg dystonia (79%), oromandibular dystonia (64%), neck dystonia (57%), blepharospasm (57%), and truncal dystonia (52%). The disease generalized in 90% of the cases within 1 to 11 years of onset (median duration, 5 years). Overall, the condition was disabling, but the Fahn-Marsden disability score did not correlate with age of onset, duration of illness, site of onset, rate of generalization, or presence of parkinsonism. Thirty-six percent of the cases displayed at least 1 of the following "parkinsonian symptoms": bradykinesia, tremor, rigidity, loss of postural reflexes and a shuffling gait. Parkinsonism was diagnosed as definite in 14%, probable in 2%, and possible in 19% of the cases. Given this high association of dystonia and parkinsonism, we propose to call the disorder X-linked dystonia-parkinsonism syndrome (XDP).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

Hydrocephalus, cervical cord lesions, and spinal deformity.

Twenty-six children (4-16 years) had hydrocephalus and spinal deformity; 22 children had scoliosis over 50 degrees, and five children had kyphosis over 100 degrees. Twenty-one children had metrizamide enhanced cord CT scans, and 12 had additional head scans. Two children died, and one was autopsied. Three children had intracranial pressures monitored during spinal surgery. All children had Type I and II Arnold-Chiari malformations, 58% had cord cavitation (syringo/hydromyelia), 67% had cord tethering. The anatomic study showed extensive fibrosis and scarring of the upper cord and brain stem, but intraoperative studies showed that there is free transmission of fluid pressure wave from the cord across the foramen magnum with a consequent rise in intracranial pressure. This study documents frequent coexistence of spinal deformity and central nervous system lesions (hydrocephalus, Arnold-Chiari malformation, cord tethering with atresia, and cord cavitation). It supports the theory that the Arnold-Chiari malformation is a primary developmental deformity and that cord cavitation noted in these patients is primarily syringomyelia formed on the basis of ischemic necrosis within the cord. The free transmission of a fluid pressure wave from the cord to the lateral ventricle supports the Williams theory of propagation of syringomyelic cavities once they have developed. It is conjectural but likely that the CNS lesions cause spinal deformity by disrupting coordinating control of spinal musculature by the normal postural reflex mechanisms. Hydrocephalic patients who develop spinal deformity require thorough investigation for CNS lesions with head scans, CT scans, and metrizamide enhanced CT scans. NMR technology, however, may supplant techniques currently employed.

Adolescent↗

Early identification of cerebral palsy in high risk infants.

This study of high risk infants aimed to identify which signs at the corrected ages of 1, 4 and 8 months were important for distinguishing those infants who later developed hypertonic cerebral palsy (CP). From a total cohort of 450 infants (350 of birthweight less than 1500 g and 100 of birthweight greater than 1500 g), 26 infants were later diagnosed as having CP and formed the study group. A control group of 26 infants from the same initial cohort who did not develop CP was matched to the study group. Both groups were followed for a minimum of 2 years. At each assessment (1, 4, 8, 24 months corrected age), all children were assessed using a standard medical examination and a detailed neurosensorimotor developmental scale that evaluated neurological signs, motor attainments, primitive reflexes and postural reactions. Each test response was graded as normal, suspect or abnormal and the results for the two groups were compared. Assessment at 1 month failed to identify a number of the CP infants whereas at 4 months there was some overidentification. At 8 months, assessment was highly predictive of cerebral palsy. Individual signs of abnormality were found to be of limited value but the presence of three or more abnormal signs at 8 months was highly predictive of CP.

Cerebral Palsy↗

Hip dislocation in cerebral palsy: selection for treatment.

Forty-five patients with cerebral palsy hip-dislocation were reviewed and it was found that some did well without treatment. For patients with hip pain, the best results were obtained with extensive resection arthroplasty: soft-tissue surgery alone was unsuccessful. Open reduction with femoral osteotomy achieved concentric reduction in all 15 patients who had this type of surgery: however, most retained their abnormal postural reflex activity to such a degree that subsequent scoliosis, pelvic obliquity, hip extension contractures and knee flexion deformities compromised the success of the hip surgery.

Adolescent↗