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At least 55 records · Page 3Linked to original sources
PubMed1988

Dynamic visual acuity with telescopic spectacles: improvement with adaptation.

Telescopic spectacles are used as aids for the visually impaired in order to increase effective visual acuity. Because ocular stabilization reflexes are not fully compensatory when telescopic spectacles are worn, head motion would be expected to produce retinal image motion which could decrease visual acuity. Using 1.0 Hz sinusoids of vertical axis head rotation, we investigated the effect of head velocity and telescopic spectacle magnification on binocular dynamic visual acuity (DVA), the acuity during head motion, in 34 normally sighted subjects. The visual field peripheral to the telescopes was masked. Up to a head velocity amplitude of 30 degrees/sec, DVA was insensitive to head velocity for X2 telescopic spectacles. For X4 and, to a greater degree, X6 telescopic spectacles, DVA decreased progressively as head velocity increased. DVA measurements were repeated after a 15 min adaptation period, during which a distant video monitor was viewed using telescopic spectacles. For X4 telescopic spectacles, DVA increased significantly after adaptation. With an unobstructed peripheral visual field, initial DVA with X4 telescopic spectacles was equal to adapted DVA with peripheral vision occluded, but adaptation produced no further improvement in DVA with the peripheral field unobstructed. These data indicate that the visual acuity obtained with telescopic spectacles is substantially reduced under conditions where head motion occurs, potentially reducing the functional value of these devices in low vision rehabilitation. The adverse effect of head motion on DVA may be reduced by adaptation.

Adaptation, Physiological↗
PubMed2002

Clinical evaluation of 70 degrees and 90 degrees laryngeal telescopes.

OBJECTIVES: Rigid telescopy is widely used in otorhinolaryngology for endolaryngeal visualization. Laryngeal telescopes are made with several angles, including 70 degrees and 90 degrees. In this study, the performances of 70 degrees and 90 degrees telescopes are compared and evaluated on the basis of ability to visualize specific regions of the larynx. METHODS: Each subject (N = 121) received evaluation with both 70 degrees and 90 degrees telescopes. The investigator used the telescopes to attempt to visualize 4 key regions: (1) the subglottic area, (2) the pyriform fossae, (3) the anterior commissure, and (4) the laryngeal surface of the epiglottis. The telescopes were connected to a video camera and videotape recordings were made. The percentage of attempted visualizations that were successful was calculated for both the 70 degrees and the 90 degrees telescopes. RESULTS: The 70 degrees telescope provided successful visualization of the subglottic area in 111 patients (91.7%), of the pyriform fossae in 115 (95.0%), of the anterior commissure in 112 (92.6%), and of the laryngeal surface of the epiglottis in 114 (94.2%). The 90 degrees telescope provided successful visualization of the subglottic area in 103 patients (85.1%), of the pyriform fossae in 112 (92.6%), of the anterior commissure in 100 (82.6%), and of the laryngeal surface of the epiglottis in 102 (84.3%). Differences in rates of visualization were significant for the posterior surface of the epiglottis, the anterior commissure, and the subglottic area. CONCLUSIONS: The 70 degrees telescope provided a significantly higher rate of successful visualization for 3 of the 4 regions studied. This result contributes information that may help the clinical examiner select an instrument of choice.

Adult↗
PubMed1978

New method for determining the magnifying power of telescopes.

A new method of measuring the power of optical telescopes is described. This method makes use of the vergence amplification that occurs when the light incident on the objective lens at a telescope is divergent or convergent. The relation between the vergence incident on the objective and vergence emergent from the eyepiece depends on the magnifying power and the length of the telescope. The method is most simple to apply to short-length, low-powered Galilean tesescopes, such as those used as low vision aids, in sports glasses, and in telescopic loupes. With such telescopes, holding a lens of known power against the objective and measuring the back vertex power of the lens-telescope combination using the lensometer and then measuring the telescope length allows the determination of the magnifying power of the telescope. The method can be adapted to determine the magnification rating of near-vision telescopic loupes.

Eyeglasses↗
PubMed2001

[Experimental model for the examination of inner pressure tolerance of telescopic anastomosis and other frequently performed anastomosis types of the esophagus].

We have good results with telescopic anastomosis technique in partial oesophagectomies and gastrectomies. As we could not find data about the healing process of telescopic anastomoses so we started experimenting. Inside pressure tolerance was examined immediately after performing anastomoses by measuring the bursting pressure using the organs of pigs slaughtered in the meat industry. Both oesophago-gastrostomies and oesophago-jejunostomies were performed with telescopic, single layer interrupted, single layer continuous, double layer interrupted and double layer continuous-interrupted technique, 9 of each anastomosis. A series of oesophago-jejunostomies were performed with EEA stapler. 99 anastomoses of 11 types were investigated. We found, that the inner pressure tolerance of telescopic oesophago-gastrostomy is better than any other single layer type variant. On the other hand the double layer type variants have much better pressure tolerance than the telescopic and other two type single layer anastomoses. The difference is statistically significant. In oesophago-jejunostomies the pressure tolerance of telescopic anastomosis is better than of the single layer interrupted type but the difference between the telescopic and single layer continuous type anastomoses is not significant. The pressure tolerance of double layer anastomosis is higher than the telescopic one but the difference is significant only in the continuous-interrupted type. The inner pressure tolerance of telescopic and EEA stapler anastomoses are equal. The investigation of additional features in anastomosis healing is in progress.

Anastomosis, Surgical↗
PubMedDate not supplied

Visual-vestibular interaction with telescopic spectacles.

Vestibularly and visually driven eye movements interact to compensate for head movements to maintain the necessary retinal image stability for clear vision. The wearing of highly magnifying telescopic spectacles requires that such compensatory visual-vestibular interaction operate in a quantitative regime much more demanding than that normally encountered. We employed electro-oculography to investigate the effect of wearing of 2x, 4x, and 6x binocular telescopic spectacles on visual-vestibular interactions during sinusoidal head rotation in 43 normal subjects. All telescopic spectacle powers produced a large, immediate increase in the gain (eye velocity/head velocity) of compensatory eye movements, called the visual-vestibulo-ocular reflex (VVOR). However, the amount of VVOR gain augmentation became limited as spectacle magnification and the amplitude of head velocity increased. Optokinetic responses during wearing of telescopic spectacles exhibited a similar nonlinearity with respect to stimulus amplitude and spectacle magnification. Computer simulation was used to demonstrate that the nonlinear response of the VVOR with telescopic spectacles is a result of nonlinearities in visually guided tracking movements. Immediate augmentation of VVOR gain by telescopic spectacles declined significantly with increasing age in the subject pool studied. Presentation of unmagnified visual field peripheral to the telescopic spectacles reduced the immediate VVOR gain-enhancing effect of central magnified vision. These results imply that the VVOR may not be adequate to maintain retinal image stability during head movements when strongly magnifying telescopic spectacles are worn.

Adaptation, Ocular↗
PubMed1993

Use of spectacle mounted telescope systems by the visually impaired.

BACKGROUND: Spectacle mounted telescope low vision aids are designed to magnify objects Spectacle telescopes are often rejected by the visually impaired because of their unusual cosmetic appearance which may call attention to their disability. METHODS: Fifty-six subjects were recruited at four independent low vision clinics and divided into two categories: 24 were current wearers of expanded field spectacle mounted telescope systems, and 32 were new wearers. New wearers underwent a randomized cross-over trial, comparing the experimental device (Ocutech VES) to one of two controls (DFV Expanded Field or Walter's Keplarian Close-focus Telescope). RESULTS: Our data show that previous telescope wearers increased their use of telescopes after introduction of the experimental device (Ocutech VES) and there was an equivalent utilization rate for new wearers. CONCLUSIONS: Visual activity patterns are not a sensitive measure of telescope benefit, but frequency of use patterns do change and appear to demonstrate a valid benefit of spectacle mounted telescopes for the visually impaired.

Adolescent↗
PubMed2005

Impact of topical anesthesia on acoustic characteristics of voice during laryngeal telescopic examination.

OBJECTIVE: The purposes of this study are to investigate the impact of topical anesthetic alone and with concurrent laryngeal telescopic examination on acoustic characteristics of vocal fold function. Comparison with phonation in controlled conditions may imply diagnostic information from the examination. STUDY DESIGN: Thirty males evaluated as having a normal voice were included in the study. The subjects were asked to phonate sustained /i/ with a naturally comfortable pitch and loudness in three consecutive experimental sequences as "control condition," "anesthetic condition," and "telescopic condition." Acoustic analysis of fundamental frequency, jitter, shimmer, and harmonic to noise ratio in the three different conditions were executed. RESULTS: The mean and standard deviation of Fo in control condition, anesthetic condition, and telescopic condition were 130.1 +/- 18.5 Hz, 125.7 +/- 19.7 Hz, and 173.2 +/- 35.1 Hz, respectively. The telescopic condition showed more negative change than that in control condition and anesthetic condition in other parameters. There was a significant difference (P < 0.001) between control condition and telescopic condition in all four parameters. CONCLUSIONS: This study showed that anesthesia has little effect on voice performance for subjects with a normal voice. On the other hand, the acoustic characteristics changed significantly during telescopic performance. When doing interpretation of acoustic data, the abnormality of the acoustic characteristics might be the result of the procedures and not reflect vocal pathology. Laryngeal variations due to manipulation of telescope should be ruled out.

Administration, Topical↗
PubMed2003

Stress distribution of abutments and base displacement with precision attachment- and telescopic crown-retained removable partial dentures.

Five types of removable partial dentures (two attachment dentures, two telescopic dentures and one clasp denture) were designed. The two attachment dentures were retained by the rigid-precision attachments with or without a stabilizing arm, and the two telescope dentures were retained with cone telescope crowns with or without cross-arch stabilization. The stresses acting on abutment teeth and denture bases and the movements of denture bases were investigated, and the influences of denture design were clarified. The stress acting on a terminal abutment tooth retained by a rigid-precision attachment or cone telescopic crown was larger than that acting on a terminal abutment tooth retained by a clasp. The attachment dentures tended to concentrate more stress at the terminal abutment tooth than did the telescopic dentures. The stress of denture base of an attachment denture and a telescopic denture was less than that of a clasp denture. There was no difference between the stresses of attachment and telescopic dentures. The displacement of the denture base tended to be less when the denture was designed with a rigid connection for the retainer and with cross-arch stabilization.

Dental Abutments↗
PubMed2003

Dimensional changes of one-piece frameworks cast from titanium, base metal, or noble metal alloys and supported on telescopic crowns.

STATEMENT OF PROBLEM: The dimensional accuracy of 1-piece frameworks cast from commercially pure titanium and used to accommodate supporting telescopic crowns has not been demonstrated. PURPOSE: To compare dimensional changes incurred in frameworks cast from commercially pure titanium, a cobalt-chromium alloy, and a noble metal (gold) alloy. MATERIAL AND METHODS: This study was based on 2 different models, both prepared to receive telescopic crowns: 1 with 4 dies, designed to measure dimensional changes of the castings in the horizontal plane; and another with 2 dies, designed to measure dimensional changes in the vertical plane. As variables for the 2-die models, the palatal shape (16- and 20-mm radius) as well as the palatal depth (20-mm radius with the smallest palatal depth of 8 mm, 16-mm radius with flat palate and palatal depth of 10 mm, 16-mm radius with greatest palatal depth of 16 mm) were studied. Ten specimens each were fabricated from a commercially pure titanium, a cobalt-chromium alloy, and a gold alloy. All castings were fabricated under standardized conditions. All measurements were taken with a computer-controlled measuring microscope at the margins of the simulated telescopic crowns; these served to calculate the ideal midpoint from which the distances between the telescopic crowns were measured. The positional relation of the telescopic crowns was determined in horizontal and vertical directions. The measurements of the cast models were compared with measurements of the original model. The distances between the dies and the angles of the chosen telescopic crowns were calculated in fractions of millimeters and the angles were measured in degrees. The Kruskal-Wallis test and the Mann-Whitney U test were used for statistical analysis. The level of significance was alpha=5%. RESULTS: With the following exceptions, none of the 3 alloy types showed significantly different results. With the 4-die model, all 3 alloys showed significant variations from the original model for chosen lengths (P=.001). For those lengths, the dimensional accuracy of the noble metal alloy was approximately 99.9% of the length of the original; for the 2 other alloys, an average value of 99.4% was determined. With the 2-die models the calculated angle was significantly different from the original model for all alloys (P=.001 or.000), independent from the palatal vault and depth. Significant differences from the original model were also found for the distance between the 2 telescopic crowns with all alloys for the 2-die model with a 16-mm depth palatal vault and a 16-mm radius (P=.001,.006, or.009). CONCLUSIONS: Within the limitations of this study, the significant different dimensional changes both for the 4-die models and the 2-die models did not depend on the type of alloy. The 2-die models demonstrated significant dimensional changes resulting from the palatal geometry of the corresponding test models; the 4-die models demonstrated a tendency to contract toward the geometric center.

Chromium Alloys↗
PubMed2001

Superiority of end-to-end versus telescoped bronchial anastomosis in single lung transplantation for pulmonary emphysema.

OBJECTIVE: To assess the influence of surgical technique (telescoped versus end-to-end anastomosis) on the incidence of bronchial anastomotic complications in patients who underwent single lung transplantation for pulmonary emphysema. METHODS: Seventy-six adult recipients of single lung transplants for pulmonary emphysema were evaluated for the presence of 3 types of major bronchial anastomotic complications: ischemia, dehiscence, and severe stenosis. Surgical technique, clinical course, and mortality were reviewed retrospectively. RESULTS: The 3 major complications were observed in 11 (34%; ischemia), 8 (25%; dehiscence), and 11 (34%; severe stenosis) of 32 telescoped bronchial anastomoses. In contrast, ischemia, dehiscence, and severe stenosis occurred in only 4 (9%), 1 (2%), and 2 (5%) of 44 end-to-end anastomoses (P =.0087, P =.0034, and P =.0012, respectively). The relative risk of ischemia, dehiscence, and severe stenosis in telescoped anastomoses was 2.1, 2.5, and 2.5, respectively, compared with end-to-end anastomoses. Five (13%) telescoped anastomoses required stent placement as compared with only 2 (5%) end-to-end anastomoses (P =.1244). Early postoperative pneumonia was more common in the telescoped anastomosis group (56%) than in the end-to-end group (32%; P =.0380). There was a trend toward shorter survival in the telescoped anastomosis group (mean survival 1045 +/- 145 days) as compared with the end-to-end group (mean survival 1289 +/- 156 days), but these differences did not achieve statistical significance (P =.2410). CONCLUSIONS: In patients who underwent single lung transplantation for pulmonary emphysema, telescoped anastomoses were associated with a higher incidence of bronchial anastomotic complications than end-to-end anastomoses.

Adult↗
PubMed2001

Use of a contact lens telescopic system in low vision patients.

This study was designed to evaluate the effectiveness of a contact lens telescopic system in patients diagnosed with low vision. Fifteen white patients (mean age 60.7 years) with visual acuity between 20/60 and 20/400 (mean 20/245) were evaluated using first a conventional telescope and subsequently a contact lens telescope (CLT). Evaluation parameters were visual acuity, amplitude of visual field, and patients' satisfaction with the systems. The mean final visual acuity attained with both systems was 20/105. No differences in visual acuity between the two systems were detected. However, the visual field was significantly different with each system. Mean visual field with the conventional telescope was 22 degrees, whereas with the CLT it was 52.1 degrees. This corresponds to a reduction of 78.2% in the field of view with the conventional telescope and of 49.5% with the CLT. Therefore, the CLT was found to provide a field of view that is 136% as great as the one provided by the conventional telescope. Younger patients are specially enthusiastic about the CLT because of its improved cosmetic appearance and visual field as compared to traditional telescopes. Aged patients tend to have more difficulty in accepting and using contact lenses daily.

Adolescent↗
PubMed1988

Modulation transfer functions of low power telescopes.

The modulation transfer functions (MTF's) of 131 low power Galilean and Pechan roof prism Keplerian telescopes comprising 20 models from 7 vendors were measured. MTF results are compared according to model, by type (Galilean or Keplerian), and magnification. Measurements were made on-axis and at the +/- 0.7 field angles. In addition to measuring tangential and radial MTF's some devices were tested with target grating azimuths of 45 degrees and 135 degrees. We also measured the effect of 3 and 6.4 mm exit pupil diameters on the MTF, and compared a color-corrected with a non-color-corrected design in monochromatic and white light. Galilean telescopes exhibited superior MTF's compared to Keplerian designs. The MTF's of Galilean telescopes tested on-axis with vertical and horizontal gratings were equivalent, as expected of rotationally symmetrical devices. However, similarly tested Keplerian telescopes exhibited significantly higher MTF's with vertical gratings. Tests at +/- 0.7 field angles showed that the tangential MTF's of Galilean telescopes were consistently poorer than radial MTF's, but the opposite was true for Keplerian telescopes. The comparatively poorer results obtained with the Keplerian telescopes are due to image doubling and deviation errors of the roof prisms that are dependent on the azimuthal orientation of the prism roof edge. Failure to adopt and maintain the same orientation of hand-held prism monoculars may result in experiencing a variable sharpness of image each time that they are used. Prism deviations of binocular devices must be controlled to avoid vertical disparities.

Lenses↗
PubMed2004

Spatial compression and adaptation with the low vision telescope.

PURPOSE: Geometrical analysis of monocular visual information specifying distance shows that a low vision telescope compresses optically specified distances by a factor about equal to its magnification. Using a group of eight visually healthy adults, we investigated the initial perceptual effect of putting on a 2x Galilean telescope and the adaptation produced by wearing the telescope. METHODS: Viewing was monocular, and the environment was only visible through the telescope. Because the telescope reduced the field of view to 13 degrees , we also tested a different group of eight visually normal adults who wore a simple monocular tube that restricted the field of view to 13 degrees . We measured perceived distance in a corridor using a visually directed open-loop walking task with distances ranging from 4 to 8 m. For both groups, monocular distance perception was measured before putting on the viewing device (baseline), immediately after putting on the viewing device (preadaptation), after wearing the viewing device during a 30-minute period of visual-motor activities (postadaptation), and immediately after taking off the viewing device (aftereffect). RESULTS: Comparing preadaptation with baseline measurements, the viewing devices produced a 15.4% initial compression of perceived distance on average. Comparing aftereffect with baseline measurements, the adaptation period produced a negative aftereffect that was 56.5% of the initial compression, thus showing substantial adaptation. The initial compression and the adaptation were highly significant effects, but neither effect was significantly different for the telescope group and the tube group. CONCLUSION: We conclude that free head movements in a structured environment can largely overcome the optically specified compression of distance produced by the 2x magnification of a low vision telescope, but there remains a significant initial compression of perceived distance that is produced by the restricted field of view. This compression can be substantially reduced by a short period of interaction with the environment.

Adaptation, Physiological↗
PubMed1999

Declination angle and its role in selecting surgical telescopes.

BACKGROUND: Clinicians usually expect manufacturers to provide properly adjusted surgical telescope products. However, to ensure optimal selection and adjustment, the clinician must understand certain contributing factors, particularly the optical declination angle. METHODS: The authors have developed a simple, stepwise approach for determining a clinician's optimal working posture and declination angle. This information is then applied to each specific surgical telescope to assist the clinician in ascertaining whether the telescopes comply, or can be made to comply, with the individual needs of the clinician. RESULTS: After the optimal working posture and declination angle have been identified and defined, any surgical magnification system can be evaluated for suitability and proper adjustment. CONCLUSIONS: Declination angle is a key feature in the selection and adjustment of surgical telescope systems, permitting telescopes to be adjusted to meet the clinician's needs instead of forcing the clinician to make compromises to fit the telescopes. CLINICAL IMPLICATIONS: Properly selected and well-adjusted surgical telescopes can enhance dental operating postures and positions, resulting in sound clinical ergonomics. Poor selection and adjustment can result in poor postures and positions.

Ergonomics↗
PubMedDate not supplied

Effect of telescopic spectacles on head stability in normal and low vision.

Telescopic spectacles, highly magnifying visual aids mounted in spectacle frames, markedly alter the visual consequences of head movements. To evaluate the effect of this altered visual feedback on head stability, angular head velocity of normally sighted and low vision subjects was measured in the roll, pitch, and yaw axes. Measurements were made under two postural conditions: (1) quiet standing; and (2) walking in place, as well as three visual conditions: (1) eyes closed; (2) unmagnified vision; and (3) vision with 4 x binocular telescopic spectacles. For normal subjects during quiet standing, both unmagnified vision and vision with telescopic spectacles tended to reduce spontaneous head velocity in all axes as compared to the eyes-closed condition. However, in low vision subjects neither unmagnified vision nor vision with telescopic spectacles produced significant changes in values of head velocity relative to those measured with eyes closed. Spontaneous head velocities for standing low vision subjects tended to be higher than in normal subjects, although not all differences were statistically significant. During walking in place, Fourier analysis demonstrated prominent frequency components related to harmonics of the walking frequency under all viewing conditions. In normal subjects, vision with telescopic spectacles, to a greater degree than unmagnified vision, reduced head velocity during walking in the roll and yaw, but not the pitch, axes. For low vision subjects, significant reductions in head velocity during walking were observed only during vision with telescopic spectacles. These findings indicate that vision reduces angular instability of the head during standing and walking. Magnification produced by telescopic spectacles further improves head stability under some conditions, although the effect of vision is least evident in the pitch axis. The stabilizing effect of vision is reduced in low vision subjects.

Adult↗
PubMed1991

Validation of physiologic predictors of successful telescopic spectacle use in low vision.

A group of 32 patients with low vision who were considered clinically appropriate candidates for visual rehabilitation with telescopic spectacles were prospectively studied before the first attempted use of these visual aids. Laboratory measurements were made of: (1) rotational head stability in pitch and yaw during quiet standing; (2) sensitivity of visual acuity with telescopic spectacles to imposed yaw head motion; and (3) ocular stabilization reflexes during passive, whole-body rotation in the horizontal plane. Predicted likelihood of successful use of telescopic spectacles was prospectively computed for each patient using the measurement of head stability in the pitch axis and the sensitivity of visual acuity with telescopic spectacles to head motion using a previously described statistical method. Patients were then given telescopic spectacles, and functional success was evaluated in the field at least 6 weeks later by independent masked observers. Although corrected visual acuities did not differ in the 24 patients in whom rehabilitation was successful or in the 8 patients in whom it was not, successful patients had statistically significantly less (P less than 0.05) angular head instability in pitch and yaw, as well as less impairment of visual acuity with telescopic spectacles during head motion. This finding was confirmed in a more clinically homogeneous subgroup of 16 patients who had low vision due to maculopathy. Gains of the 0.1 Hz horizontal vestibulo-ocular reflex (VOR) and visual-vestibulo-ocular reflex (VVOR) with 4X telescopic spectacles did not differ between patients in whom rehabilitation was successful and those in whom it was not.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1983

Bioptic telescopic spectacle is a hazard for operating a motor vehicle.

The primary purpose of the bioptic telescopic spectacle is to permit the driver to pass the visual requirement to operate a motor vehicle. It is paradoxical that a driver can pass the vision test only by the use of a telescope but that he cannot drive while looking through the telescope. Rather, he must drive with his limited vision (sometimes legal blindness) while looking through the carrier lens. He can use the telescope only for reading a sign or for distinguishing an object, and even then he must lower his head to look through it. This is hazardous: he becomes thus "blind" to the traffic while reading the sign through the telescope. Such a driver could never pass a peripheral vision test due to the blind areas created in the peripheral field. It is more humane and reasonable to grant a waiver for the impaired vision than to compel a handicapped person to purchase a bioptic telescopic spectacle to pass the visual requirement.

Automobile Driver Examination↗
PubMed2000

Distance telescopes: a survey of user success.

The distance telescope has a historical reputation for causing difficulties in prescribing and adaptation. Hence, we considered that a retrospective survey of patients at Nottingham Low Vision Clinic might elucidate specific attributes that influence an individual patient's success in using a distance telescope. From 142 patients prescribed distance telescopes since the Clinic's inception, 133 apparently remained users and were mailed a preliminary three-question enquiry about usage of their distance telescopes. The 87 respondents were followed up with questionnaire 2, requesting explicit information about usage, namely frequency, degree of ease or difficulty, and purpose. Older patients required higher magnification (p < 0.025). Seventeen of 74 respondents to questionnaire 2 had various adaptational problems, which are discussed; 57 of 74 patients found their distance telescopes easy to use, and 49 of 57 were frequent users. Thus, ease and frequency are linked (p < 0.05). People tended to use their distance telescopes outdoors and indoors with similar frequency (p > or = 0.29). Adaptation was found to be unrelated to visual acuity, binocularity/monocularity, ocular pathology, or restricted mobility; magnification seemed to be influential, although not significantly. Aging did not significantly impede adaptation. We infer that the universal criterion for selecting treatable patients seems to be personality type. We conclude that adaptation to a device is dependent upon active recognition of its benefits, paralleled with a tolerance of its constraints, which combine to make usage easy and regular on at least one common task.

Adaptation, Physiological↗