Reliability in dream research: a methodological note.

The coefficients of internal consistency and retest reliability had been rarely investigated within the methodology of dream content analysis. Analyzing a dream series of elderly, healthy persons obtained from weekly telephone interviews, the internal consistency of a series of 20 dreams and retests after 4 or 22 weeks, respectively, had been computed. The findings indicate that dream recall and dream length are quite stable, but dream characteristics such as bizarreness and emotional tone underlie large intraindividual fluctuations. In order to obtain reliable measures for these variables which will be important for correlational studies, including waking-life trait measures, one has to obtain as many dreams as possible (about 20) in a very short time period. Further research is needed to extend the present findings to diary dreams and laboratory dreams.

A preliminary study of dream-telling among mentally healthy elderly: no adverse effects on life or sleep quality.

While there have been several studies about dreams and dreaming among the elderly, there does not seem to have been any study of the effects of regular dream-telling (without interpretation). Listening to dreams could become a regular part of caring for the elderly and infirm. The effects of regular dream-telling in mentally healthy elderly clinical research volunteers were measured on several variables using standardized testing and self-report: life satisfaction, intrapsychic boundaries, sleep quality, sleep duration, dream recall, dream tone, and dream epoch, and were compared with two control groups. The six variables showed no significant differences among the three groups, indicating that dream-telling produced no adverse effects. The present findings seem to imply that dream-telling is not dangerous for mentally healthy individuals and may thus serve as a baseline for future studies involving geriatric patients with mental disorders or elderly undergoing significant life-events, e.g., bereavement or retirement, using the method of regular dream-telling.

Temporal summation measurements with the Octopus 1-2-3 perimeter.

Until recently, measurements of temporal summation required the construction of specialized instrumentation or the custom modification of an existing perimeter, which meant that such testing was unstandardized and relatively expensive. This precluded extensive use of this type of visual response testing, especially in a clinical setting. In an effort to change this situation, a personal computer (PC) program has been devised that makes use of a new interface for remote operation of the Octopus 1-2-3 automated perimeter. The program can be used to measure temporal summation at 1-5 locations in the visual field (0 degrees-30 degrees eccentricity) for 1-10 stimulus durations (5.6-999 ms) in the presence or absence of background illumination (10 cd/m2). Two auxiliary programs for analyzing the resulting data have been developed as well. Preliminary measurement trials were performed on four normal and two glaucomatous eyes at three test locations for ten stimulus durations in both the presence and the absence of background illumination. Ten examinations were carried out for each eye to reduce the effects of short-term fluctuations. The resulting temporal summation curves and the associated critical durations were similar to those found in the literature. No effect of disease on the critical duration was found (n = 2). With this program package, the effects of disease on temporal summation can now be tested using a commercially available instrument. To determine its clinical usefulness, though, investigations with larger populations will have to be made.

Problems related to diffuse versus localized loss in the perimetry of glaucomatous visual fields.

The separation of diffuse loss from more localized loss in the glaucomatous visual field is desirable for a number of reasons. In previous papers, the characteristics of several methods and algorithms for distinguishing among normal visual fields and those exhibiting diffuse and localized loss have been described and compared. In particular, a new diffuse loss index has been introduced that serves to decide whether or not a diffuse loss component is present and, if so, helps to estimate the amount. Here the approaches utilized for calculating empiric probability maps (Heijl) and the pattern deviation plots (STATPAC) are compared with results obtained with the diffuse loss index algorithm. Based on 197 Octopus G1 examinations of glaucomatous visual fields, it is shown that both methods produce large differences when compared with the diffuse loss index. For this and other reasons, it is argued that both empiric probability maps and pattern deviation plots may lead the inexperienced clinician to ignore valuable information concerning actual pathology.

A comparison of unweighted and fluctuation-weighted indices (within the central 28 degrees of glaucomatous visual fields measured with the Octopus automated perimeter).

The main visual field indices of Flammer and the analogous ones of Heijl have been compared based on a population of 113 glaucomatous visual fields. It is shown that for the population studied, the differences between the two sets of indices are negligible for Octopus G1 program results and that they may thus be used interchangeably.

A new diffuse loss index for estimating general glaucomatous visual field depression.

Experience with a number of visual fields has shown that the algorithm used earlier for estimating general depression in glaucomatous visual fields was too conservative. A new, more sophisticated algorithm for calculating diffuse loss has been devised and the results obtained in the evaluation of 20 glaucomatous visual fields were compared with those obtained manually. The new algorithm is less restrictive, yet produces values for diffuse loss which agree well with the empirical estimates (R = 0.97, N = 14). The new diffuse loss index is also compared with the mean defect index (R = 0.77, N = 159), the 18th Bebie curve ranked value (R = 0.87, N = 159), and the previous diffuse loss index (R = 0.98, N = 105). A general discussion of various aspects of diffuse loss is included.

Evaluating human and automated interpretation of visual field data in perimetry.

The complexity of visual field result evaluation has increased with the advent of automated perimetry. This in turn makes software assistance such as provided by the new Octosmart program interesting and desirable. Its accuracy and reliability in visual field evaluation must be tested, though, and the testing methodology itself must be developed. For this purpose, 27 visual fields were evaluated by three human interpreters and the Octosmart program. Based on a newly developed compound index, the performance of the three interpreters and Octosmart is described and a high degree of consistency is demonstrated.

A comparison of the mean defect and mean deviation indices within the central 28 degrees of the glaucomatous visual field.

The mean defect index of Flammer and the mean deviation index of Heijl have been compared based on a study of 169 glaucomatous visual fields. It is shown that in the cases studied the differences between the two indices are negligible for Octopus G1 program results and that they may thus be used interchangeably.

BSPOT: a blind spot data evaluation program for SAPRO examinations.

The BSPOT evaluation program has been created to run on an IBM-PC type computer. It accepts Octopus SAPRO data that have been transferred to the PC and enables the user to display aspects of the data for evaluation purposes. Some applications are illustrated using the results of two blind spot examination series, one normal and the other pathologic, and the results of an angioscotoma examination. Although the program was designed for the display of blind spot data, any SAPRO examination data may be used.

Clinical interest and problems related to the measurement of the blind spot and the pericoecal region by means of programs SAPRO, SAPPAR, and BSPOT.

Difficulties encountered when measuring the differential light sensitivity of the blind spot and its surroundings and the clinical interest of such measurements are reported. The determination of the differential light sensitivity across step gradients, as well as abrupt changes observed at and close to the blind spot, may pose severe problems, because both are strongly influenced by even slight fixation instability. However, other factors reported herein may be equally important. The insight gained here may be cautiously extrapolated to the difficulties (and to the efforts to overcome them) encountered when measuring other scotomata in the visual field having sensitivity distributions similar to those of the blind spot. The sensitivity distribution in the blind spot and the pericoecal region may be important in a number of disease entities, particularly in glaucoma and neurologic diseases.