A do-it-yourself membrane-activated auditory feedback device for weight bearing and gait training: a case report.

An augmented auditory feedback device comprised of a thin membrane switch mini-buzzer, and battery is described as a modification of a previously described feedback device. The membrane switch can be customized for the patient and is designed to fit inside a patient's shoe without altering the heel height. Its appeal lies in its simplicity of construction, low cost, and ease of implementation during a patient's training for weight bearing and gait. An ever-present source of information, it provides performance-relevant cues to both patient and clinician about the occurrence, duration, and location of a force component of motor performance. The report includes suggested applications of the device, instructions to construct it, and a case report in which the device was used to improve weight bearing and gait in a cognitively healthy person with spina bifida.

Paraplegia subsequent to administration of tissue plasminogen activator and intravenous heparin following myocardial infarction--a case report.

A case involving spinal epidural hematoma following tissue plasminogen activator and intravenous heparin therapy administered after acute myocardial infarction is reported here. The symptoms of spinal epidural hematoma following thrombolytic therapy are outlined and a recommended course of action for arriving at a definitive diagnosis of suspected epidural hematoma is provided.

The effects of circumferential wrist pressure on reproduction accuracy of wrist placement in healthy young and elderly adults.

BACKGROUND: The purpose of this study was to determine the effect of circumferential wrist pressure on reproduction accuracy of wrist placement in healthy young and elderly adults. A convenience sample of 20 young adults having a mean age of 22.9 years and 20 elderly adults with a mean age of 68.2 years participated in the study. METHOD: Blindfolded subjects were asked to actively self-select a neutral wrist position (reference) and then, when signaled, to actively reproduce the previously selected position. Wrist joint reproduction accuracy was assessed under four pressure conditions: no contact, wrist contact, 10 mm Hg, and 20 mm Hg. A single axis dynamic wrist electrogoniometer measured three dependent variables: absolute, constant, and variable errors. Data were analyzed by means of multivariate analysis of variance (MANOVA) for repeated measures. RESULTS: No significant differences in reproduction accuracy under the four pressure conditions for young or elderly adults were found. CONCLUSIONS: Healthy young and elderly adults may utilize existing intrinsic feedback and central control mechanisms to achieve accuracy during a reproduction task. Some subjects in both age groups who entered into the study with high error scores benefited from circumferential pressure by possibly relying on peripheral mechanisms. Further studies are needed to determine the effect of circumferential pressure on subjects with poor reproduction performance.

Effects of contextual interference and conditions of movement task on acquisition, retention, and transfer of motor skills by women.

This experiment was designed to investigate varying conditions of contextual interference within two different conditions of movement tasks during acquisition on the acquisition and retention of a computerized task and transfer to a functional skill. Performance of head movements was conducted under open- or closed-task conditions and with random or blocked schedules of practice. Analysis indicated that learning under the open-task condition resulted in better retention and transfer than the closed-task condition. It is suggested that increasing the within-trial variability in the open-task condition produced a contextual interference effect. In this regard, support for Battig's predictions is provided by the current findings in that the high variability present during the open-task condition was more beneficial for retention and transfer than the low variability present during the closed-task condition. Differences between random and blocked schedules of practice on the retention and transfer data were not statistically significant.

Patterns of motor impairement in normal aging, mild cognitive decline, and early Alzheimer's disease.

In order to determine the relationship between cognitive dysfunction and motor behavior in older adults, 41 cognitively normal elderly (NL), 25 cases exhibiting mild cognitive impairment (MI), and 25 patients with mild Alzheimer's disease (AD) were examined using a broad array to motor/psychomotor and cognitive tests. Relative to the NL group, MI individuals (at risk for future decline to AD) performed worse on tasks involving fine and complex motor function (e.g., tracking and manual dexterity). AD patients also exhibited motor dysfunction on tasks assessing relatively more rudimentary motor control. Motor tasks were able to distinguish NL vs MI and NL vs mild AD individuals as effectively as cognitive tests of memory and language. These results indicate that motor impairment is an important aspect of cognitive decline in older adults. Motor/psychomotor assessments may be comparably sensitive to traditional tests of cognitive function in identifying persons affected by the earliest stages of AD pathology.

Motor/psychomotor dysfunction in normal aging, mild cognitive decline, and early Alzheimer's disease: diagnostic and differential diagnostic features.

To determine the association between cognitive dysfunction and motor behavior in older adults, 41 cognitively normal elderly (NL), 25 nondemented patients exhibiting mild cognitive impairment (MI) and at risk for future decline to dementia, and 25 patients with mild (early) Alzheimer's disease (AD) were examined using a wide array of motor/psychomotor and cognitive assessments. The three groups were recruited from an aging and dementia research center and were composed of well-characterized physically healthy volunteers, with similar ages and gender distributions. The outcome measures included 16 motor/psychomotor tests categorized a priori into gross, fine, and complex, as well as eight cognitive tests of memory and language. Relative to the NL group, MI individuals performed poorly on cognitive, fine, and complex motor measures but not on gross motor tests; AD patients performed worse on cognitive and all motor domains. Differences in complex motor function persisted after adjustment for performance on cognitive and on less complex motor tests. Classification analyses showed similar accuracies in discriminating NL from MI and NL from AD cases for both complex motor (79% and 92% accuracy, respectively) and cognitive tests (80% and 93% accuracy, respectively). Less complex motor tests produced poorer accuracies. Among nondemented subjects, education correlated with several cognitive scores but no motor scores. These results indicate that motor impairment is an important aspect of cognitive decline in older adults. Motor/psychomotor assessments were found to be comparably sensitive to traditional tests of cognitive function in identifying persons affected by the earliest stages of AD pathology and may improve identification of at-risk nondemented elderly, especially among diversely educated individuals.

An augmented auditory feedback device.

An augmented auditory feedback device is described. The device can be easily and economically constructed and implemented during a patient's physical rehabilitation. The rationale is to provide an external source of information to the user in order to correct errors during weight-bearing activities. Possible applications of the augmented auditory feedback device include increasing symmetry and weight distribution during sitting, standing, and gait. Instructions regarding its construction are provided, and a case study using the device is presented. Improved midline alignment and weight distribution in sitting for a 2-hour duration was achieved by a stroke patient using the augmented auditory feedback device in conjunction with physical therapy.

Individual differences in ability to use EMG-derived feedback.

Evidence shows statistically reliable individual differences among unimpaired subjects in ability to use visual representation of electromyographic voltages. The visual information was displayed as a cursor in a tracking situation. The cursor was then blanked, with subjects being required to place the now invisible cursor over a target. Test-retest correlational significance is demonstrated. The rationale for using visual guidance in rehabilitating stroke victims suffering from loss in motor feedback receives support.

Visually displayed EMG feedback: single case studies of hemiplegic upper extremity rehabilitation.

The efficacy of visually displayed EMG feedback in treating hemiplegic upper limb motor disorders was investigated in 5 patients (0.5-4 years poststroke). A single case experimental method "multiple-baseline across target behaviors" was used to compare performance during the feedback phase to that occurring in the monitored baseline phase. The nonfeedback baseline phase was followed by the staggered introduction of audiovisual feedback for each of the targeted pairs of muscles. EMG feedback obtained from muscle pairs (shoulder: anterior deltoid and upper trapezius; elbow: brachial triceps and biceps; digits: extensor digitorum communis and digit flexors) was displayed as two distinct waveforms on a videomonitor during therapy. Nonfeedback assessment of each of the three pairs was performed during each session. The effects of feedback were not uniformly distributed. Elbow control responded best, and statistical tests confirmed the effects of intervention observed clinically in all 5 patients. Clinical improvements in shoulder flexion were observed in 4 patients but could be statistically attributed to EMG gains in just 1. Improvement in finger extension observed clinically in 3 patients was statistically attributable to EMG gains in 2. All patients regained control of at least one target activity. EMG gains were accompanied by increases in active range of motion and by varying functional improvement. Marked functional gains in 3 patients were obtained with recovery of finger control.

Helping hemiparetics to help themselves. Sensory feedback therapy.

Despite the presence of some voluntary movement, the loss of discrete control impairs functioning of the arm and hand in most hemiparetics. Seventy hemiparetic patients, aged 12 to 78 years, were treated and followed up for six months to three years. Electromyographic activity monitored from dysfunctional primary movers during attempted movement was displayed to the patients as a continuous oscilloscopic trace, reflecting generated muscle activity and allowing its quantification. Coupled with operant conditioning techniques, these displays were modified gradually by reinforcing the patient's effort with auditory feedback during successive approximations to a desired level. Such therapeutic use of electromyographic displays often resulted in a progressive improvement of voluntary movement. More than half the patients acquired and retained purposive movements that meaningfully improved their functional capabilities.