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PubMed2003

Incidence of supraglottic activity in males and females: a preliminary report.

Supraglottic activity was rated from flexible endoscopic video recordings of subjects with normal laryngeal structure and function as they sustained vowels and repeated syllables and sentences. Judges rated these recordings for false vocal fold (FVF) adduction and anterior-to-posterior (A-P) compression at the initiation of the speech task, throughout the whole speech task (static supraglottic activity), and as brief individual adductions within a speech task (dynamic supraglottic activity). Significant differences in A-P (p < 0.0003) and FVF (p < 0.0000001) compression were found between tasks. Dynamic FVF activity was associated with glottal stops. Static A-P and FVF activities were present in males significantly more (p < 0.0001) than females. FVF activity associated with speech initiation was found in females significantly more (p = 0.0256) than males. Supraglottic activity plays a role in normal speech production, and should not necessarily be considered suggestive of a voice use pattern with excessive muscle tension.

Adult↗

PubMed1998

ESS, eye stimulator system for VVIS facility (Visual and Vestibular Investigation System).

The ESS (Eye Stimulation System) is one of four main Subsystems of the Visual and Vestibular Investigation System ( VVIS ), Facility developed in the field of EDEN program and aimed to the research in the area of neurosensors physiology under microgravity conditions. In particular, the ESS is an Optokinetic Stimulator that stimulates the Subject's eyes with moving black and yellow patterns, in order to allow, by another main Subsystem, video recording of the pupil movement and, successively, to elaborate the relevant data of the neurovestibular experiment. This Stimulator was designed by the Officine Galileo as Subcontractor of Aerospatiale, leader of the VVIS facility, developed under ESA contract and successfully flown in April 1998 aboard the Neurolab mission. The Eye Stimulation System, on the frame of the VVIS Facility, is used in conjunction with the Body Rotating Device and the Eye Movement and Recording System, in order to fulfill all operations that lead to carry-out the experiments proposed. The Subject, seated on the Rotating Chair, observes the stimuli on a display monitor through a set of lenses, mounted on a proper box, fixed to a main structure of the unit. The stimuli patterns are showed on a display, placed on a movable support in order to fix it in a proper position, depending on the optical characteristics of the Subject. The experiments are repeated with different kind of patterns. All the main components of the visual system are mounted on a structural base plate, that gives also the mechanical I/F with the other system, supporting the ESS.

Computer Graphics↗

PubMed1997

Some methodological issues in the assessment of the spontaneous eyeblink frequency in man.

Previous assessments of spontaneous eyeblink frequency (SEBF) or interblink intervals (IBI) have been made over period of 0.5 to 15 min and average values calculated; the reliability of the methods has not been validated. Video recordings were made of 14 healthy volunteers, aged 20 to 38 years, while silently fixating on a 2 m distant, 35 mm high target under 350 lux illumination and the traces assessed with an event marker. Significant fluctuations in SEBF or IBI were generally observed, but which did not conform to a minute-by-minute periodicity. Time-dependent trends were uncommon, although uncritical pooling or averaging of data can effectively conceal such fluctuations or trends. Correlation's between SEBF and IBI indicate that eyeblink monitoring over at least 3 min is required. Simple averaging calculations are not appropriate because of a high chance of non-Gaussian distribution of data. Modal IBI values correlated well with an adjusted modal calculated SEBF which is thus recommended for further use.

Adult↗

PubMed2006

Behavioural responses to different floor space allowances in small groups of laying hens.

Under Council Directive 1999/74/EC, minimum space allowances per laying hen range from 550 cm(2) in unfurnished cages to 1111 cm(2) in alternative housing, and to 40,000 cm(2) outdoors for free-range hens. In official reports on the welfare of laying hens, there is recognition that knowledge of their space requirements is inadequate. This experiment studied expression of behaviour, including spacing, in five groups of six and one group of five ISA Brown hens aged 21-33 weeks in an adjustable test pen providing 600, 2400, 4800, 7200, 9600, and 12,000 cm(2) floor area per hen. Each group was tested with every treatment. Home pens provided 2400 cm(2) per hen. The main aim was to identify a hypothetical point at which mutual repulsion equals mutual attraction (a 'broken stick' response). Sequencing of treatments was according to a Latin square design, daytime tests lasted 2 h and had no feeder or drinker present, and overnight tests were done with 2400, 7200 and 12,000 cm(2) per hen with a feeder and drinker present. Groups were video-recorded from above to allow repeated measurements of spacing and other behaviours. In daytime tests, the relationship between mean distance to nearest neighbour and floor space allowance was asymptotic, rather than a 'broken stick'. The steepest part of the response was between 600 and 4800 cm(2) per hen. Changes in other behaviours were greatest between 600 and 2400 cm(2), and there was no significant change above 7200 cm(2). Spacing behaviour responses at night were the same as by day. It is concluded that any space allowance of less than about 5000 cm(2) per hen imposes at least some constraint on free expression of behaviour, and that hens would benefit from any increase above the current minimum 1111 cm(2) usable area in alternative housing.

Animal Welfare↗

PubMed1991

In vitro videographic comparison of argon and Nd:YAG laser iridotomy.

We used an in vitro technique with high-magnification video recording to evaluate from the posterior side of the iris the immediate sequence of events during argon and Nd:YAG laser peripheral iridotomy. The observed effects differed strikingly. The argon laser caused a gradual mounding up of iris pigment epithelium with each successive energy application before final penetration. This effect was reduced but not eliminated with higher power levels. The Nd:YAG laser caused complete disruption and dispersal of the pigment epithelium with a single pulse of energy. Additionally, a multiple focal point configuration of the Nd:YAG laser was observed to produce a significantly larger iridotomy than a single focal point configuration for comparable energy settings. These observations may in part explain the observed clinical advantage of the Nd:YAG laser over the argon laser for creation of a patent iridotomy.

Humans↗

PubMed2006

A new generation videokymography for routine clinical vocal fold examination.

OBJECTIVE: This study aims to introduce a new-generation videokymographic system, which provides simultaneous laryngoscopic and kymographic image, for routine clinical vocal fold examination. STUDY DESIGN: The authors explored a new imaging method for diagnosis and evaluation of voice disorders. METHODS: The new-generation videokymographic system includes two charge-coupled device image sensors, a color area image sensor, and a monochromic high-speed line-scan image sensor. The high-speed line-scan image sensor is used to capture the kymogram, and the color area image sensor is used to obtain the laryngoscopic image. The two images can be displayed simultaneously on a video monitor or stored in a standard video recorder. Three subjects with nonpathologic voice were investigated in detail with the new videokymographic system. RESULTS: The high-quality laryngoscopic image and kymogram can be used directly for clinical purposes with no further postprocessing. The scan position of the kymogram is always indicated in the laryngoscopic image, which provides feedback for the operator to easily locate the expected scanning position. All varieties of vocal fold vibration, including irregular vibrations, phonation onset and offset, can be observed with the presented method. The continuous kymogram of the vocal fold vibration can be retrieved from a kymographic image sequence for quantitative analysis. CONCLUSIONS: The new-generation videokymography provides a simple, quick means to investigate vocal fold vibration, especially for voice disorders. It can emerge as an important tool for routine clinical vocal fold examination.

Data Display↗

PubMed2001

Self-motion perception: assessment by real-time computer-generated animations.

We report a new procedure for assessing complex self-motion perception. In three experiments, subjects manipulated a 6 degree-of-freedom magnetic-field tracker which controlled the motion of a virtual avatar so that its motion corresponded to the subjects' perceived self-motion. The real-time animation created by this procedure was stored using a virtual video recorder for subsequent analysis. Combined real and illusory self-motion and vestibulo-ocular reflex eye movements were evoked by cross-coupled angular accelerations produced by roll and pitch head movements during passive yaw rotation in a chair. Contrary to previous reports, illusory self-motion did not correspond to expectations based on semicircular canal stimulation. Illusory pitch head-motion directions were as predicted for only 37% of trials; whereas, slow-phase eye movements were in the predicted direction for 98% of the trials. The real-time computer-generated animations procedure permits use of naive, untrained subjects who lack a vocabulary for reporting motion perception and is applicable to basic self-motion perception studies, evaluation of motion simulators, assessment of balance disorders and so on.

Adult↗

PubMedDate not supplied

Footfall patterns, stride length and speed of vertical climbing in spider monkeys (Ateles fusciceps robustus) and woolly monkeys (Lagothrix lagotricha).

Vertical climbing is central to theories surrounding the locomotor specialisations of large primates. In this paper, we present spatiotemporal gait parameters obtained from video recordings of captive spider monkeys (Ateles fusciceps robustus) and woolly monkeys (Lagothrix lagotricha) in semi-natural enclosures, with the aim of discovering the influence of body weight and differences in general locomotor behaviour on vertical climbing kinematics on various substrates. Results show that there are only few differences between gait parameters of climbing on thin trees, vertical and oblique ropes, while climbing on large-diameter trees differs considerably, reflecting the higher costs of locomotion on the latter. At the same speed, Ateles takes longer strides and the support phase takes a smaller percentage of cycle duration than in Lagothrix. Footfall patterns are more diverse in Ateles and include a higher proportion of ipsilateral limb coupling. Compared to other primates, the gait characteristics of vertical climbing of atelines most closely resemble those of African apes.

Analysis of Variance↗

PubMedDate not supplied

Videoanalysis of chemokinesis: characterization of speed, persistence and orientation in an agarose assay.

Time-lapse video recording and off-line computer analysis were used to characterize the chemokinetic behavior of individual human neutrophils migrating in an agarose assay. When neutrophils were stimulated with an isotropic concentration of formyl-methionyl-leucyl-phenylalanine (fMLP), they migrated with a mean speed of 9.6 micron per min and oriented at random. The ratio of net displacement to total distance travelled (persistence of locomotion) was 0.66, indicating that neutrophils maintained some directional persistence even in the absence of a gradient of fMLP. The speed and persistence of locomotion index were correlated because both faster and slower cells had high persistence, while only slower cells had low persistence. The orientation angle was independent of both speed and persistence of locomotion. These are the first reported direct measurements of the chemokinetic locomotion of neutrophils using the agarose assay.

Chemotaxis, Leukocyte↗

PubMed2002

Localization of epileptogenic zone in temporal lobe epilepsy by ictal scalp EEG.

Our aim was to evaluate the ability to localize the epileptogenic zone in temporal lobe epilepsy (TLE) by ictal scalp electroencephalogram (EEG). Using simultaneous video recording, we analysed scalp EEG activity during ictal periods in 38 patients (30 patients with medial TLE (MTLE) and eight with lateral TLE (LTLE)). In 14 patients, intracranial ictal EEGs were recorded with depth electrodes, and simultaneous recordings of scalp and intracranial EEG were performed in 11 patients. Scalp EEG showed that, in all 30 patients with MTLE (71 of 72 seizures), an attenuation of background activity was observed before the appearance of ictal activity. Ictal discharges first appeared in the scalp EEG when the ictal discharges reached the lateral part of the temporal lobe on the intracranial EEG. While, in all eight patients with LTLE (25 of 25 seizures), the attenuation of background activity did not occur before the appearance of ictal activity. When the ictal discharges started in the lateral temporal lobe on intracranial EEG, ictal discharges appeared on the scalp. MTLE and LTLE could be diagnosed by the presence or absence of attenuation of background activity with clinical ictal signs before the appearance of ictal discharges.

Adolescent↗

PubMed2006

The use of hazard road signs to improve the perception of severe bends.

Collision analysis indicates that many car accidents occur when negotiating a bend. Excessive speed and steering wheel errors are often given by way of explanation. Nevertheless, the underlying origin of these dramatic errors could be, at least in part, a poor estimation of bend curvature. The aim of this study was to investigate both the assessment of bend curvature by drivers and the impact of symbolic road signs that indicate a hazardous bend on this assessment. Thus, participants first viewed a video recording showing approaching bends of different curvature before being asked to assess the curvature of these bends. This assessment could either be a verbal (symbolic control) estimation of the bend's curvature and risk, or a sensorimotor (subsymbolic control) estimation of the bend's curvature (participants were asked to turn a steering wheel to mimic the position that would be necessary to accurately negotiate the bend). Results show that very severe bends (with a radius of less than 80 m) were actually underestimated. This was associated with an underestimation of risk corresponding to these bends and a poor sensorimotor anticipation of bend curvature. Road signs, which indicate risk significantly improve bend assessment, but this was of no use for sensorimotor anticipation. Thus, other indicators need to be envisaged in order to also improve this level of control.

Accidents, Traffic↗

PubMed2005

Automated video analysis of age-related motor deficits in monkeys using EthoVision.

Previous studies comparing age-related changes in locomotor function in nonhuman primates have generally relied on subjective human observations or rudimentary infrared motion sensors. Here, we used the automated video-tracking system EthoVision to objectively quantify locomotor activity in 6 young, 6 middle-aged and 12 aged female rhesus monkeys. The video records were analyzed for distance traveled, movement speed and vertical activity. Our results showed that the young monkeys (4.9 +/- 0.1 years old) traveled twice the distance and moved 48% faster than the middle-aged monkeys (15.7 +/- 0.5 years old), and traveled thrice the distance and moved 67% faster than the aged monkeys (26.3 +/- 0.9 years old). In addition, young monkeys were vertically more active (20/60 min) than both the middle-aged (7/60 min) and the aged (1/60 min) monkeys. Furthermore, the locomotor performance of the individual animals significantly correlated with increasing age for all three measures. We conclude that EthoVision is a reliable and objective tracking method for detecting age-related differences in locomotor movements in rhesus macaques, and possibly in humans.

Aging↗

PubMed2001

Magnetic field exposure and behavioral monitoring system.

To maximize the availability and usefulness of a small magnetic field exposure laboratory, we designed a magnetic field exposure system that has been used to test human subjects, caged or confined animals, and cell cultures. The magnetic field exposure system consists of three orthogonal pairs of coils 2 m square x 1 m separation, 1.751 m x 0.875 m separation, and 1.5 m x 0.75 m separation. Each coil consisted of ten turns of insulated 8 gauge stranded copper conductor. Each of the pairs were driven by a constant-current amplifier via digital to analog (D/A) converter. A 9 pole zero-gain active Bessel low-pass filter (1 kHz corner frequency) before the amplifier input attenuated the expected high frequencies generated by the D/A conversion. The magnetic field was monitored with a 3D fluxgate magnetometer (0-3 kHz, +/- 1 mT) through an analog to digital converter. Behavioral monitoring utilized two monochrome video cameras (viewing the coil center vertically and horizontally), both of which could be video recorded and real-time digitally Moving Picture Experts Group (MPEG) encoded to CD-ROM. Human postural sway (standing balance) was monitored with a 3D forceplate mounted on the floor, connected to an analog to digital converter. Lighting was provided by 12 offset overhead dimmable fluorescent track lights and monitored using a digitally connected spectroradiometer. The dc resistance, inductance of each coil pair connected in series were 1.5 m coil (0.27 Omega, 1.2 mH), 1.75 m coil (0.32 Omega, 1.4 mH), and 2 m coil (0.38 Omega, 1.6 mH). The frequency response of the 1.5 m coil set was 500 Hz at +/- 463 microT, 1 kHz at +/- 232 microT, 150 micros rise time from -200 microT(pk) to + 200 microT(pk) (square wave) and is limited by the maximum voltage ( +/- 146 V) of the amplifier (Bessel filter bypassed).

Animals↗

PubMed1993

Relative phase quantifies interjoint coordination.

This note illustrates by example how expression of joint movement on a phase plane can quantitatively describe multijoint coordination during complex actions. Automatic digitisation of high-speed video records was used to obtain lumbar vertebral, hip, knee and ankle joint angular kinematics in the sagittal plane of a subject performing a symmetric two-handed lifting movement. A consistent proximal-to-distal coordination was illustrated via angle-angle and relative phase angle presentations. During bending to pick up a load, the joints began their movement in the order proximal to distal while the reverse order of joint involvement occurred during extension. Phase angle relationships between joints may provide sufficiently sensitive measurements to identify changes in multijoint coordination induced by alterations in task variables such as (in the case of lifting) object mass, lifting height and load moment. Information regarding multijoint coordination is likely to be important in attempting to understand the respective roles and interaction between the bi and monarticular muscles which are involved in everyday complex actions like lifting.

Adult↗

PubMed1999

Newborns spontaneous arm movements are influenced by the environment.

The spontaneous arm movements of 28 healthy full-term newborn infants were observed for 1 min in four different environmental conditions: each infant was placed in a vertical position in a bathtub filled with water with the water level up to her or his neck in a vertical position in water with the water level up to her or his waist in a supine position out of the water in a vertical position out of the water. It was hypothesised that these different environmental constraints would influence the infants spontaneous activity. From video recordings spontaneous arm movements were categorised according to the classifications of Hannan (Hannan TE. Young infant's hand and finger expressions: An analysis of category reliability. In: Field T, Fogel A, editors. Emotion and Early Interaction. New Jersey: Elbaum 1982;253-265). The statistical analyses showed, firstly, that the frequency of occurrence of various arm movements is greater out of the water than in the water. Secondly, for those out of the water the frequency of occurrence of various arm movements is greater in the vertical position in comparison to the supine position. Thirdly, the infants showed more active arm movements (more upward movements) in the vertical position out of the water in comparison to the two water and supine conditions. These findings lead to the conclusion that different environmental constraints influenced the spontaneous arm movements.

Arm↗

PubMed2006

Program development of reminiscence group work for ageing people with intellectual disabilities.

BACKGROUND: The goal of this study was to adapt a narrative reminiscence program for the special needs of ageing people with mild/moderate intellectual disabilities. Research has shown that stimulating reminiscence in the elderly can be a meaningful activity, and holds promise for positive effects on well-being. METHOD: In the first stage (10 weeks), the program was developed with 1 group. Evaluation and adjustments to the program were made based on video recordings, the researcher's log, and feedback from participants and support workers. Formative evaluation was performed by means of a within-group analysis. In the second stage (3 weeks), the program was introduced to 6 other groups. Interviews with professional support workers were subjected to a cross-case analysis. RESULTS: The final program consists of 13 sessions covering different reminiscence themes. The success of reminiscence group work relies on (a) well-prepared and structured sessions, (b) adequate use of visual triggers, and (c) facilitating, coaching and moderating. CONCLUSION: The program was perceived as a valuable and meaningful activity by all participants. Although reminiscence group work is not therapeutic in nature, it may have therapeutic use for ageing people with intellectual disabilities, and in this sense is worth evaluating.

Adaptation, Psychological↗

PubMed1998

A bronchoscopic, computer-assisted examination of the changes in dimension of the infant tracheal lumen with changes in head position: implications for emergency airway management.

BACKGROUND: Resuscitation guidelines caution against extreme extension or flexion of an infant's head because tracheal obstruction may occur. No data support this recommendation. The authors therefore examined the dimensions of the tracheal lumen in neutral, extended, and flexed head positions in infants undergoing general endotracheal anesthesia for elective surgery. METHODS: Eighteen healthy full-term infants were studied. A flexible fiberoptic bronchoscope was passed through a previously inserted endotracheal tube and positioned above the cricoid cartilage. Video recordings were taken in each of three head positions. Recordings were analyzed by an investigator blinded to head position. A computer-digitized technique was used to measure anterior-posterior and lateral dimensions and cross-sectional area. Data were analyzed using paired t tests and sign tests. RESULTS: No significant differences in mean tracheal dimensions with changes in head position were found. No infant had complete tracheal obstruction. Infants were equally as likely to have a small increase as they were to have a small decrease in tracheal dimension with changes in head position. CONCLUSIONS: Despite the belief that infants and neonates have obstruction at the level of the trachea with extreme positions of the head, the authors were unable to demonstrate this phenomenon.

Airway Obstruction↗

PubMed2006

Patients' ability to react before complex partial seizures.

OBJECTIVE: The purpose of the study described here was to investigate the pathophysiology of patients' ability to react during the conscious (aura) phase of complex partial seizures (CPS) originating from the temporal lobe. METHODS: We reviewed video recordings of CPS experienced by 130 adult patients who had undergone epilepsy surgery for intractable medial temporal lobe epilepsy. All patients were instructed to push the alarm button when they felt an aura. We defined the preictal reactivity as the ability to push the alarm button before the complex partial (unconscious) phase of seizures. RESULTS: Seventy-seven patients (59%) pushed the alarm button before seizures. Patients with preictal reactivity were significantly younger, more often had lateralized EEG seizure patterns, and had a better postoperative outcome. Patients who did not push the alarm button had secondarily generalized seizures more often. CONCLUSIONS: Ability to react before CPS is associated with a circumscribed region involved at seizure onset and spread, and with a seizure-free postoperative outcome.

Adolescent↗