کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
9424342 1295261 2005 11 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
The pointillism method for creating stimuli suitable for use in computer-based visual contrast sensitivity testing
موضوعات مرتبط
علوم زیستی و بیوفناوری علم عصب شناسی علوم اعصاب (عمومی)
پیش نمایش صفحه اول مقاله
The pointillism method for creating stimuli suitable for use in computer-based visual contrast sensitivity testing
چکیده انگلیسی
An increasingly large corpus of clinical and experimental neuropsychological research has demonstrated the utility of measuring visual contrast sensitivity. Unfortunately, existing means of measuring contrast sensitivity can be prohibitively expensive, difficult to standardize, or lack reliability. Additionally, most existing tests do not allow full control over important characteristics, such as off-angle rotations, waveform, contrast, and spatial frequency. Ideally, researchers could manipulate characteristics and display stimuli in a computerized task designed to meet experimental needs. Thus far, 256-bit color limitation in standard cathode ray tube (CRT) monitors has been preclusive. To this end, the pointillism method (PM) was developed. Using MATLAB® software, stimuli are created based on both mathematical and stochastic components, such that differences in regional luminance values of the gradient field closely approximate the desired contrast. This paper describes the method and examines its performance in sine and square-wave image sets from a range of contrast values. Results suggest the utility of the method for most experimental applications. Weaknesses in the current version, the need for validation and reliability studies, and considerations regarding applications are discussed. Syntax for the program is provided in an appendix, and a version of the program independent of MATLAB® is available from the author.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Journal of Neuroscience Methods - Volume 142, Issue 2, 30 March 2005, Pages 219-229
نویسندگان
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