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PubMed1968

The LSD syndrome. A review.

lsd (lysergic acid diethylamide) is a powerful bio-active substance related to serotonin in structure. Its actions generally affect autonomic, sensory and psychological functions. Autonomic stimulation is varied. Sensory responses are usually visual, involving heightened and distorted color perception and fusion of sensory impressions. Psychological responses include a feeling that a unique experience is occurring; feelings of depersonalization; pronounced fluctuation of mood; time and space distortions; autistic phenomena; fluctuation of aggressive drives (usually reduction); and spontaneous reoccurrence of the lsd experience. THE SUBJECTIVE RESPONSES CAN BE RELATED TO THREE BASIC PHENOMENA: (1) expectation; (2) loss of characteristic modes of perceptual and cognitive patterning; and (3) hypersuggestibility. THE MAJOR ADVERSE REACTIONS ARE: (1) chronic drug dependence including subsequent personality changes and depressive reactions; and (2) acute ego dissolution. These reactions usually occur in already emotionally ill people. Most of these users fall into two groups, those with unresolved identity problems and those with severe ego abnormality. The majority of adverse reactions are of the chronic drug dependence type and are usually seen in adolescents and young adults who have not negotiated the age-appropriate tasks of forming and integrating the various identities that are the composite of their life experiences.lsd helps alleviate these stresses via some of its psychological properties as discussed. It also provides a nidus for the formation of a subculture where goals for social, sexual and vocational achievement are lower and idiosyncratic modes of adaptation are better tolerated. A smaller group of users who have serious reactions such as psychosis, rage reactions, homicidal and suicidal ideation are usually found to have preexisting ego abnormality such as ambulatory schizophrenia, chronic impulse disorders and borderline states. Although adverse reactions most often appear to be related to pre-morbid psychopathology, this is not invariably so. Further, there is as yet no reliable method to determine who will have an adverse reaction and what the nature of that reaction will be.

Color Perception↗
PubMed1996

Visual cortical dysfunction in Alzheimer's disease evaluated with a temporally graded "stress test" during PET.

OBJECTIVE: Visual-processing abnormalities commonly contribute to typical Alzheimer's disease symptoms, but their detailed pathophysiology remains unknown. To investigate why patients with Alzheimer's disease have greater difficulty performing visuoconstructive (magnocellular-dominated) tasks than face- or color-perception (parvocellular-dominated) tasks, the authors measured brain activation in response to a temporally graded visual stimulus (neural stress test) during positron emission tomography. METHOD: The stress test measured regional cerebral blood flow (CBF) in response to a patterned flash stimulus in the resting state (0 Hz in the dark) and at frequencies of 1, 2, 4, 7, and 14 Hz. Ten patients with Alzheimer's disease and 12 age- and sex-matched comparison subjects were studied. RESULTS: The striate response at 7 Hz and 14 Hz (the degree of regional CBF increase from that at 0 Hz) was significantly less in the patients than in the comparison subjects, whereas the change in regional CBF at the lower frequencies did not differ between groups. In bilateral middle temporal association areas activated by motion and dominated by magnocellular input, regional CBF at 1 Hz (the frequency with maximal apparent motion) was significantly greater than at 0 Hz in the comparison subjects but not in the patients. CONCLUSIONS: The magnocellular visual system normally responds to high-frequency input and motion; the failure of response in the striate cortex at high but not low frequencies in the Alzheimer's patients suggests greater magnocellular than parvocellular dysfunction at these levels. Activation failure in the middle temporal areas in the patients supports magnocellular dysfunction. The finding that the Alzheimer's disease group had abnormal visual cortical function emphasizes the importance of clinical visuospatial evaluation of patients with Alzheimer's disease to fully understand symptom production and to plan interventions.

Aged↗
PubMed1976

Color perimetry.

Seven subjects were studied to determine the reproducibility of color isopters utilizing a Tubingen perimeter with targets equated for radiant energy and separate for heterochromatic flicker luminance. Achromatic threshold recognition of targets for equal luminance gave smaller isopters with longer wavelengths (red). Color recognition thresholds, on the other hand, showed large blue, midzone red and green, and small yellow isopters. The target recognition and color recognition thresholds for equal energy targets gave smaller red isopters. The data support Traquair's contention that all color isopters would be equivalent if hue, saturation, and intensity were equated. Clinically, the detection of subtle peripheral and central field defects might reside in the use of appropriately selected equally bright-colored targets.

Color Perception↗
PubMed1979

Photoreceptor misalignment accompanying a fibrous scar.

A 9-year-old boy with dense fibrous scars at the macula had visual acuities of 6/12 and 6/9 and an abnormal color match (pseudoprotanomaly). The Stiles-Crawford effect functions were abnormal in both eyes, showing maximal sensitivity at the nasal edge of each pupil. The data suggest that the foveal photoreceptors, although spared destruction by an adjacent focus of healed chorioretinitis, have been distorted by fibrous traction arising from that defect.

Child↗
PubMed1981

Digoxin retinal toxicity. Clinical and electrophysiological evaluation of a cone dysfunction syndrome.

A 70-year-old man was studied both during and after resolution of clinical digoxin toxicity using color vision tests, ganzfeld electroretinography and electro-oculography. Concomitant administration of quinidine sulfate probably contributed to digoxin toxicity. Abnormalities in color vision and subnormal amplitude and prolonged implicit time for cone-mediated electroretinogram (ERG) responses suggested a cone dysfunction syndrome. The electro-oculographic light-to-dark ratio during clinical toxicity was high for our laboratory, but this is probably normal. Notable improvement was seen in color vision and the ERG after cessation of digoxin therapy. Inhibition of sodium-potassium adenosine triphosphatase by digoxin probably influences normal uptake of extracellular potassium by Müller's cells and other retinal neurons. This mechanism may contribute to subnormal, prolonged cone-mediated ERG responses in retinal toxic reactions from cardiac glycosides.

Adaptation, Ocular↗
PubMed1983

Clinical studies of color vision with Gunkel's chromagraph.

Color thresholds in a series of patients with local or systemic diseases were determined by a chromagraph method and subjected to computer analysis. When compared with normal persons, those with optic nerve disease (multiple sclerosis, optic neuritis, and optic atrophy) showed an overall weakness for all colors (enlarged neutral areas), with an additional specific defect in the orange-cyan (greenish blue) axis. Those with the two retinal diseases studied (macular degeneration and retinitis pigmentosa) also showed threshold elevation for all colors, but with a special defect in the yellow-blue axis. The general elevation was greater for patients with retinitis pigmentosa than for those with macular degeneration, regardless of the visual acuity. In patients undergoing treatment for systemic lupus erythematosus and rheumatoid arthritis, there was a mild elevation of the color threshold, especially for yellow.

Arthritis, Rheumatoid↗
PubMed1984

Correlation between color vision scores and quantitative perimetry in suspected glaucoma.

The mean differential threshold, studied on the Octopus perimeter, and color vision, estimated by the Farnsworth-Munsell 100-Hue test, were studied in glaucoma suspects and patients with questionable early field defects. The results of both tests were significantly correlated. The color vision scores correlated with the central, paracentral, and midperipheral parts of the visual field. This result suggests that both functions are disturbed in glaucoma and that the disturbance may be present diffusely throughout the visual field.

Aged↗
PubMed1985

Association of hue discrimination loss and diabetic retinopathy.

The results of Farnsworth-Munsell 100-hue, visual acuity, and visual field testing were compared with the severity of retinopathy in a group of 90 diabetic patients. The patients showed significantly higher than expected Farnsworth-Munsell 100-hue scores, with a tritanlike axis, compared with published age norms for nondiabetic individuals. The magnitude of the acquired blue-yellow hue discrimination defect correlated significantly and to a similar extent with both the severity of overall diabetic retinopathy and the severity of macular edema and hard exudate formation. Visual acuity loss correlated somewhat more significantly with macular edema than with overall retinopathy, whereas the converse was true for visual fields. For all visual function tests, the correlations were more significant for fluorescein leakage in the macula than for capillary nonperfusion in the macula. Abnormal hue discrimination was found in 65% (32/49) of eyes with proliferative diabetic retinopathy, suggesting a potential role for this test in screening for proliferative diabetic retinopathy in primary care facilities. Also, because the ability of diabetic patients with color vision deficiency to perform color-dependent tests for urinary and blood glucose may be impaired, such patients should be made aware of this potential problem.

Adult↗
PubMed1987

Age covariance between 100-Hue color scores and quantitative perimetry in primary open angle glaucoma.

Color vision tests have shown promise as an early indicator of optic nerve compromise in primary open angle glaucoma (POAG). In this context, it is of interest to know how well color test performance correlates with an accepted measure of glaucomatous optic nerve damage, such as is provided by quantitative static perimetry. We found correlation values for 96 glaucoma suspects (ocular hypertensive patients) and 110 patients with POAG. No significant correlation values were found for the suspect group when age correction was applied to the color variable. Similarly, for the patients with POAG, age correction of the color test scores reduced all age group correlation values below significance, except for the age group 60 to 69 years. These findings conflict with another recent study reporting significant correlation between Farnsworth-Munsell 100-hue color test scores and visual field performance for glaucoma suspects but which did not correct for age. We interpreted our results for the glaucoma suspects and patients with glaucoma to indicate some independence of mechanisms responsible for early color loss compared with visual field loss.

Adult↗
PubMed1987

Clinical measures of central vision function in glaucoma and ocular hypertension.

A generalized loss of visual sensitivity, even for foveal targets, has been reported as an early sign of glaucoma. In the present study of central vision, we used relatively simple and rapid clinical tests of color thresholds, color discrimination, and spatial contrast sensitivity to compare the vision of three age-matched groups of patients who had primary open angle glaucoma (n = 33) or ocular hypertension (n = 32) as well as normal subjects (n = 24). The largest sensitivity losses for both glaucoma and ocular hypertensive groups were disclosed by a color threshold test with blue lights designed to isolate the blue-sensitive pathways of the visual system. The loss of sensitivity for both the glaucoma group and the ocular hypertensive group is consistent with recent reports (from postmortem studies of human eyes) of extensive axon death even in the absence of glaucomatous field defects.

Aged↗
PubMed1987

Assessing color vision loss among solvent-exposed workers.

Acquired color vision loss has been associated with exposure to organic solvents in the workplace. However, not all tests of chromatic discrimination loss are designed to detect acquired, as opposed to congenital, loss. The Lanthony D-15 desaturated panel (D-15-d), a simple 15 cap color arrangement test, designed to identify mild acquired dyschromatopsia, can be administered rapidly in the field, under standard conditions. The objective of the present study was to evaluate the D-15-d among 23 solvent-exposed workers of a paint manufacturing plant, by comparing the results obtained with the D-15-d to those obtained with the Farnsworth-Munsell 100 Hue (FM-100), a highly sensitive measure of color vision loss. The D-15-d revealed a significantly higher prevalence of dyschromatopsia among the ten highly exposed workers (80%) as compared to the 13 moderately exposed workers (30.8%); FM-100 results revealed one false positive. All dyschromatopic workers presented blue-yellow loss; the FM-100 detected eight complex patterns, while the D-15-d identified 5. Comparison of D-15-d and FM-100 scores were highly correlated (corr. coeff. 0.87; p less than 0.001). Multiple regression analyses showed both scores to be significantly related to age and exposure level. The findings of this study indicate that the D-15-d is an adequate instrument for field study batteries. However, the FM-100 should be used for more detailed assessment.

Color Perception↗
PubMed2001

Effects of low-level occupational exposure to styrene on color vision: dose relation with a urinary metabolite.

To investigate the threshold effects of chronic low-level occupational exposure to styrene on color vision, we examined color discrimination in 105 male workers exposed to styrene (mean age 37.7 years; mean length of exposure 6.2 years; mean urinary concentration of mandelic acid 0.21 g/L) and in 117 referents (mean age 37.7 years). We also assessed the effects of styrene by examination of the nature of the relation between disorders of nervous function and age, alcohol consumption, and other variables. A standardized questionnaire was adopted to collect information about work history, occupational or nonoccupational solvent exposure, alcohol consumption, and drug use. Color vision was evaluated by the Lanthony desaturated panel D-15 test. The results of the test were expressed as the color confusion index (CCI). There was a dose-dependent relationship between the urinary concentration of mandelic acid and color vision loss. The CCIs of the subgroups whose urinary mandelic acid levels were 0.1-0.2 and >0.2 g/L were significantly higher than those of each referent group (P<0.05 and P<0.01, respectively), but not in the subgroup whose urinary mandelic acid level was lower than 0.1 g/L. Our study suggests that a low level of styrene, presumably 0.1-0.2 g/L, involves the risk of inducing adverse effects on color vision. After confounding factors were adjusted for, the urinary mandelic acid level had a significant positive relationship with color vision.

Adult↗
PubMed1983

Genetic markers and alcoholism.

Genetic markers are genetically determined characteristics that have been found to occur in association with some common disorders. In alcoholism, four types of genetic markers have been studied to determine their frequency compared with the general population frequency. The markers studied are blood groups and serum proteins, secretion of ABH blood group substance, phenylthiourea taste sensitivity, and color vision defects. There have been found to be significant associations between alcoholism and all the above markers apart from blood groups and serum proteins. However, the associations appear to result from acquired rather than inherited factors.

ABO Blood-Group System↗
PubMed1982

Statistical demonstration of minor colour vision abnormalities.

Analysis of the results from 94 male and 94 female young normal trichromats on the 100 hue test and the Nagel and Pickford-Nicolson anomaloscopes that colour deviant and/or colour weak subjects can be distinguished from the wholly normal bulk by considering the normality of certain test result distributions as well as by considering the combinations between test results considered abnormal. The stated minor abnormalities of colour vision are frequent and their types are those described by Pickford and by Lakowski (never' colour asthenopia). They are recognised by means of the anomaloscopes and not by means of the 100 hue test.

Adolescent↗
PubMed1984

Results from a simple laser color perimeter.

Stimulus size, chromaticity, adaptation, luminance and local adaptation are more easily controlled when laser light rapidly scans the appropriate portion(s) of the visual field. Adaptation of a Ferree-Rand perimeter to the use of He-Ne laser light gives chromatic and achromatic thresholds of relatively low variance.

Adaptation, Ocular↗
PubMedDate not supplied

X-linked cone dystrophy.

A description is given of a new family with X-linked cone dystrophy. A survey is also given of the findings in X-linked cone dystrophy. When an eye specialist sees a male patient with myopia and reduced visual acuity, the cause of which is not clear from the fundus picture, an X-linked cone dystrophy should be considered. Electrophysiological examination, combined with detailed testing of colour vision, can provide an explanation of the poor vision which satisfies both the patient and the ophthalmologist.

Adult↗
PubMed1991

Color vision and age in a normal North American population.

Color vision is known to change with age. We conducted the Farnsworth-Munsell (FM) 100-Hue and the Lanthony Desaturated Panel D-15 (DD-15) tests in 115 normal North American subjects aged 5-81 years to obtain age-specific norms for these procedures. For each test, color discrimination was best between the ages of 20 and 50 years. Both increasing age and the occurrence of lens changes were significantly associated with increasing 100-Hue error scores. Age-specific norms for the 100-Hue test were comparable with those obtained by Verriest in a European population, but such norms for the DD-15 test are problematic. Our data indicate somewhat greater variability in the DD-15 than in the 100-Hue test.

Adolescent↗