We present a new fall-detection method using a floor sensor based on near-field imaging. The test floor had a resolution of 9 × 16. The shape, size, and magnitude of the patterns are used for classification. A test including 650 events and ten people yielded a sensitivity of 91% and a specificity of 91%.

Objective: Both clinically observable and subclinical hemispatial neglect are related to functional disability. The aim of the present study was to examine whether increasing task complexity improves sensitivity in assessment and whether it enables the identification of subclinical neglect. Method: We developed and compared two computerized dual-tasks, a simpler and a more complex one, and presented them on a large, 173 × 277 cm screen. Participants in the study included 40 patients with unilateral stroke in either the left hemisphere (LH patient group, n = 20) or the right hemisphere (RH patient group, n = 20) and 20 healthy controls. In addition to the large-screen tasks, all participants underwent a comprehensive neuropsychological assessment. The Bells Test was used as a traditional paper-and-pencil cancellation test to assess neglect. Results: RH patients made significantly more left hemifield omission errors than controls in both large-screen tasks. LH patients’ omissions did not differ significantly from those of the controls in either large-screen task. No significant group differences were observed in the Bells Test. All groups’ reaction times were significantly slower in the more complex large-screen task compared to the simpler one. The more complex large-screen task also produced significantly slower reactions to stimuli in the left than in the right hemifield in all groups. Conclusions: The present results suggest that dual-tasks presented on a large screen sensitively reveal subclinical neglect in stroke. New, sensitive, and ecologically valid methods are needed to evaluate subclinical neglect.

In this paper, a low-frequency RFID location system based on a matrix of quad antennae placed under a floor surface is described. A prototype system was used for parameterisation and feasibility tests. The results show that it is possible to build a location system using floor quad antennae.

Accelerometer-based seismocardiography and sternal acceleration ballistocardiography are promising approaches to the noninvasive detection of precordial vibrations. However, in order to be widely accepted as diagnostic or even prognostic tools, clinical validation and standardization of these methods are necessary. In precordial vibration studies, using all three axes instead of one in cardiac vibration analysis is anticipated to enable more accurate cardiac event detection. Simultaneously acquired electrocardiography, photoplethysmography, and respiration information are considered as promising ways to enhance seismocardiogram analysis. In this article, an easy-to-use system that combines three-dimensional seismocardiography, electrocardiography, photoplethysmography, and respiration measurements is described, and its performance is demonstrated. In the test measurements, the system demonstrated its capability to capture accurate cardiovascular data.

A computerized device for simultaneous measurement of coordinative and reactive skills related to driving was developed and tested in two consecutive trials of psychoactive agents in healthy volunteers. The test system comprises a vehicle, a driving computer (Sinclair QL), and the programming and measurement computer (IBM-PC). The computerized driving programme projects to the colour--TV screen a winding road, and the driver has to keep the car on the road by turning the steering wheel. The driving proceedes at a fixed, fairly rapid rate for 5 min., and the numbers of tracking errors (deviations from the road) as well as the tracking percentage (relative length of the track driven off the road) were computed separately for both halves of the track. During the latter half of the track 60 visual or/and sound stimuli were given in random order, and the driver had to respond or not respond to them by pressing a button or by pushing a foot pedal. The number of reaction errors and the cumulative reaction time were recorded. The programme also provides a histogramme that relates the number of deviations from the road to their duration, enabling a visual judgement of the severity of errors. Matched versions (mirror image, reverse direction) of tracks of varying severity were offered to reduce learning effect during the trial. When testing the device in two placebo-controlled double-blind and cross-over trials, a considerable practice effect on tracking and reaction strategies took place, but after proper training the baselines remained reasonably stable.(ABSTRACT TRUNCATED AT 250 WORDS)

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The stroke is one of the most prevalent health and well being risks world-wide. In stroke patient rehabilitation, retrieving the ability to walk is an important goal. In addition to that, the gait should be sufficient for independent mobility in the community, thus eliminating the risk of more severe immobilization, falls and health deterioration. In this paper the requirements of a comprehensive and flexible mobility rehabilitation system -a proactive space are presented. The focus area of the system is described and motivated. The requirements cover the instrumentation and software. The realized pilot space is described.

Objective: Patients with unilateral stroke commonly show hemispatial neglect or milder contralesional visuoattentive deficits, but spatially non-lateralized visuoattentive deficits have also been reported. The aim of the present study was to compare spatially lateralized (i.e., contralesional) and non-lateralized (i.e., general) visuoattentive deficits in left and right hemisphere stroke patients. Method: Participants included 40 patients with chronic unilateral stroke in either the left hemisphere (LH group, n = 20) or the right hemisphere (RH group, n = 20) and 20 healthy controls. To assess the contralesional deficits, we used a traditional paper-and-pencil cancellation task (the Bells Test) and a Lateralized Targets Computer Task. To assess the non-lateralized deficits, we developed a novel large-screen (173 × 277 cm) computer method, the Ball Rain task, with moving visual stimuli and fast-paced requirements for selective attention. Results: There were no contralesional visuoattentive deficits according to the cancellation task. However, in the Lateralized Targets Computer Task, RH patients missed significantly more left-sided than right-sided targets in bilateral trials. This omission distribution differed significantly from those of the controls and LH patients. In the assessment of non-lateralized attention, RH and LH patients missed significantly more Ball Rain targets than controls in both the left and right hemifields. Conclusions: Computer-based assessment sensitively reveals various aspects of visuoattentive deficits in unilateral stroke. Patients with either right or left hemisphere stroke demonstrate non-lateralized visual inattention. In right hemisphere stroke, these symptoms can be accompanied by subtle contralesional visuoattentive deficits that have remained unnoticed in cancellation task.