Charles Maitland

The effects of balance training and high-intensity resistance training on persons with idiopathic Parkinson’s disease

OBJECTIVE To assess immediate and near-term effects of 2 exercise training programs for persons with idiopathic Parkinsons disease (IPD). DESIGN Randomized control trial. SETTING Public health facility and medical center. PARTICIPANTS Fifteen persons with IPD. INTERVENTION Combined group (balance and resistance training) and balance group (balance training only) underwent 10 weeks of high-intensity resistance training (knee extensors and flexors, ankle plantarflexion) and/or balance training under altered visual and somatosensory sensory conditions, 3 times a week on nonconsecutive days. Groups were assessed before, immediately after training, and 4 weeks later. MAIN OUTCOME MEASURES Balance was assessed by computerized dynamic posturography, which determined the subjects response to reduced or altered visual and somatosensory orientation cues (Sensory Orientation Test [SOT]). Muscle strength was assessed by measuring the amount of weight a participant could lift, by using a standardized weight-and-pulley system, during a 4-repetition-maximum test of knee extension, knee flexion, and ankle plantarflexion. RESULTS Both types of training improved SOT performance. This effect was larger in the combined group. Both groups could balance longer before falling, and this effect persisted for at least 4 weeks. Muscle strength increased marginally in the balance group and substantially in the combined group, and this effect persisted for at least 4 weeks. CONCLUSION Muscle strength and balance can be improved in persons with IPD by high-intensity resistance training and balance training.

Evoked potentials in the evaluation of visual field defects due to chiasmal or retrochiasmal lesions

We used monocular full-field and hemifield pattern reversal stimulation to study visual evoked potentials (VEPs) in 20 patients with confirmed defects of the visual pathways. In 10 of 12 patients with homonymous field defects, it was possible to lateralize the brain lesion but not to predict the site of the lesion within the hemisphere. In four of eight patients with bitemporal field defects, VEPs suggested involvement at the chiasmal level. In the remaining cases, VEPs provided no correlation with perimetric and radiologic findings. We found that VEPs usually corroborated other diagnostic studies but subtle defects were not detected reliably, and large hemianopic defects were occasionally not lateralized accurately. VEP analysis is therefore of only limited value in assessment for clinical purposes of patients with homonymous or bitemporal hemianopias.

Talking while walking: Cognitive loading and injurious falls in Parkinson's disease

Multitasking has become a way of life, from operating multiple software packages simultaneously on a computer, to carrying on a conversation on a cell phone while driving. Perhaps one of the most common dual tasks performed is talking while walking. In isolation, neither task would be considered difficult to perform, yet when coupled, the relative ease of each task may change. This paper details significant problems that result from injurious falls, and points out the vulnerability of those who have been diagnosed with Parkinsons disease. In addition, it provides an illustrative study that demonstrates the potential danger of talking while walking, especially when the cognitive-linguistic complexity of verbal tasks is manipulated. In this investigation, 25 participants with Parkinsons disease and 13 participants without neurological compromise completed gait tasks while conducting tasks of low (counting by ones), middle (serial subtraction of threes), and high load (alpha-numeric sequencing). The results indicated that cognitive-linguistic demand had an impact on gait, the effects of which were demonstrated in individuals without neurological compromise as well as those with Parkinsons disease. One finding, altered double-support time, distinguished the Parkinson group from the control participants. These results suggest that it might be prudent for healthcare professionals and caregivers to alter expectations and monitor the cognitive-linguistic demands placed on elderly individuals, particularly those with neurological compromise who might be at greater risk for injurious falls.