ChronicNeurotoxins, Inc. Visual Contrast Sensitivity Test Center
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Did you know? If you have the VCS deficit, the potential for biotoxin exposure and don’t have other exposures or medical conditions that could explain the deficit, our data indicate that the response to toxin-binding therapy is over 90%.

To Learn More and purchase VCS Test and/or Treatment Protocols, Please Register (at NO COST) or log in.

Read Frequently Asked Questions >>

How the VCS Test Works

The visual system includes a complex neurological network that involves the retina, optic nerve, brain nuclei and the visual cortex. One of the main outputs of the visual system is pattern vision. The VCS tests is an indicator of ability to detect visual patterns. The test measures the least amount of contrast between light and dark bars (sinusoidal grating) that is needed for the viewer to detect the bars. VCS is measured at five different bar sizes (spatial frequencies) because perception of different bar sizes is mediated by different physiological components, and these components are differentially susceptible to effects from different toxic substances (10-17). The largest effects of biotoxins are at the mid-size bars (1-8). To measure VCS, viewers are presented a series of bar patterns at each of the five bar sizes. Viewers respond by indicating that the bars are tilted to the left, tilted to the right, are straight up and down, or that they cannot see any bars. The pattern with the lowest contrast that is correctly identified is the measure of VCS for that bar size. Upon completing the VCS test, viewers receive a message indicating that biotoxins are (positive) or are not (negative) likely to be involved in their illness. The criteria for getting a "positive" VCS result is set high to avoid false positive results. This occasionally results in a false negative result; some cases of chronic-biotoxin induced illness may pass the VCS test a some times. VCS can be measured during treatment to monitor recovery.

No guarantees for a cure for any disease are implicitly or explicitly given to anyone. No single vision test can fully describe function of the visual system or conclusively indicate the presence or absence of neurotoxins or neurotoxicity. Diagnoses cannot be made and medications cannot be prescribed without seeing a physician in person.

ChronicNeurotoxins, Inc.
500 Market Street
Pocomoke City, MD 21851

Privacy Policy | © 2002-2010 ChronicNeurotoxins, Inc.

Prior to launching a new version of this website in June, 2002, the earlier version had been online for about a year and a half. Over 3,600 registered users had taken the preliminary and VCS tests. About half of the test results were positive for potential chronic, neurotoxin-induced illness. We do not know exactly how many of those used our treatment protocol with their local physician, or the outcome for all that did. We do know, however, that many used the protocol with success.