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Color vision, initiated from the cone photoreceptors, is essential for fish to obtain environmental information. Although the visual impairment of triazine herbicide prometryn has been reported, data on the effect of herbicide such as prometryn on natural color sensitivity of fish is scarce. Here, zebrafish were exposed to prometryn (0, 1, 10, and 100 μg/L) from 2 h post-fertilization to 160 days post-fertilization, to explore the effect and underlying mechanism of prometryn on color perception. The results indicated that 10 and 100 μg/L prometryn shortened the height of red-green cone cells, and down-regulated expression of genes involved in light transduction pathways (arr3a, pde6h) and visual cycle (lrata, rpe65a); meanwhile, 1 μg/L prometryn increased all-trans-retinoic acid levels in zebrafish eyes, and up-regulated the expression of genes involved in retinoid metabolism (rdh10b, aldh1a2, cyp26a1), finally leading to weakened red and green color perception of female zebrafish. This study first clarified how herbicide such as prometryn affected color vision of a freshwater fish after a long-term exposure from both morphological and functional disruption, and its hazard on color vision mediated-ecologically relevant tasks should not be ignored., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

The zebrafish is extensively used as a model organism for studying several disorders of the central nervous system (CNS), including epilepsy. Some antiseizure drugs (ASDs) have been shown to produce discrepant results in larvae and adults zebrafish, therefore, their anticonvulsant efficacy in subsequent stages of the pentylenetetrazole (PTZ)-induced seizures should be more precisely characterized. The purpose of this study was to investigate behavioral effects of five classic ASDs: valproate (VPA), phenytoin (PHT), carbamazepine (CBZ), diazepam (DZP), and phenobarbital (PB) administered intraperitoneally (i.p.) in the PTZ-induced seizure test in adult zebrafish. We determined the time of maximal effect and the dose-response relationship of the studied ASDs. Furthermore, we assessed changes in the locomotor activity and the anxiety-like behavior in the color preference test. Moreover, drug concentrations in zebrafish homogenates were examined. VPA, DZP, and PB significantly increased the seizure latency at three subsequent stages of seizures (SI-SIII). PHT produced the anticonvulsant-like effect at SI and SII, while CBZ was effective at SII and SIII. Only DZP decreased zebrafish locomotor activity. A strong anxiolytic-like effect was observed after administration of PHT and PB. A weak anxiolytic-like effect occurred after treatment with VPA and DZP. The HPLC analysis showed the average concentrations of the studied ASDs in the fish body during the maximum anticonvulsant activity of each drug. Our results confirm the advantages of using zebrafish with the mature CNS over larval models and its utility to investigate some neuropharmacological properties of the tested drugs., (Copyright © 2021 Elsevier Inc. All rights reserved.)

Purpose: To longitudinally evaluate the visual function and structure of patients taking ethambutol by various modalities and identify useful tests for detection of subclinical ethambutol-induced optic toxicity., Methods: This retrospective study enrolled 84 patients with newly diagnosed tuberculosis treated with ethambutol. Best-corrected visual acuity (BCVA), color vision, contrast sensitivity, fundus and retinal nerve fiber layer (RNFL) photography, automated visual field (VF) test, and optical coherence tomography (OCT) were performed: prior to starting; every month during administration, and 1 month after stoppage. We longitudinally compared visual function and structure with the baseline and identified the occurrence of subclinical toxicity., Results: BCVA, color vision, and contrast sensitivity showed no change from the baseline. Mean temporal RNFL thickness was significantly increased at 6 months (p = 0.014). Subclinical toxicity was found in 22 eyes of 14 patients (i.e., 13% of 168 eyes), in the forms of VFI decrease (VF index, 9 eyes of 6 patients), quadrant RNFL thickness increase (5 eyes of 4 patients), and VF pattern defect (12 eyes of 6 patients). 73% of the patients showed recovery to the baseline at 1 month post-stoppage. The risk factors for occurrence of subclinical toxicity were age, cumulative dose, and medication duration., Conclusion: Mean temporal RNFL thickness increased after administration. The VFI, quadrant RNFL thickness, and VF pattern defect could prove useful in assessment of subclinical toxicity. Medication duration was shown to be a strong risk factor for occurrence of subclinical toxicity., Competing Interests: The authors have declared that no competing interests exist.

Schizophrenia patients (SCZ) demonstrate deficits in many domains of mental functioning, including visual perception. An issue that has been relatively unexplored, in terms of explaining variation in visual function in SCZ, however, is medication use. The present study explored potential medication effects on color vision in SCZ, a process that is strongly linked to dopaminergic function in the retina. SCZ patients who had clear-cut either typical (n = 29) or atypical (n = 29) monotherapy, without any other concurrent medication, and a group of age- and gender-matched healthy controls participated in the study. Color vision was assessed by the Cambridge Colour Test, using the Trivector and Ellipse subtests. The results demonstrated impaired color perception in patients with schizophrenia, especially in those receiving typical antipsychotics, but these deficits were subtle and not generalized to all parameters. Our findings are consistent with the known neurophysiology of the retina and visual pathways, and with the effects of dopamine blocking medications, but the results should be carefully interpreted., (Copyright © 2018. Published by Elsevier B.V.)

It has been reported that the use of certain stimuli can lead to anxiety-like behavior in zebrafish. Moreover, visual stimulation of zebrafish is becoming a popular tool. Here we evaluated the effects of six colors combinations and alprazolam, a benzodiazepine which is widely used in the treatment of anxiety disorders, on the behavior of adult zebrafish in a two-chambered apparatus, which chambers were illuminated by red/yellow, green/blue, red/green, green/yellow, red/blue and blue/yellow light. The following parameters were measured: time spent in the zone, number of entries to the zone, time of freezing, distance traveled and average speed in the zone. We report that the adult zebrafish spent more time in the red zone compared to yellow or green as well as in the yellow or blue compared to green. The zebrafish displayed a concomitant increase in time freezing in the red zone compared to yellow or green as well as in the yellow or blue compared to green. Moreover, average speed was decreased in the red zone compared to yellow or green and in the yellow zone compared to green. Treatment with alprazolam significantly affected the behavior of the zebrafish, e.g., following alprazolam administration time spent in the zone and time freezing were longer in the green zone than in red. Based on these observations, we suggest that light color combinations could be effective to manipulate zebrafish behavior and could be useful in neuropsychopharmacological studies, perhaps to study anxiety-like behavior and the effects of anxiolytic agents., (Copyright © 2017 Elsevier Inc. All rights reserved.)

The extensive usage of xenobiotic endocrine disrupting chemicals (XEDCs), such as Bisphenol A (BPA), has created obvious threat to aquatic ecosystems worldwide. Although a comprehensive understanding of the adverse effect of BPA on behaviors and physiology have been proven, the potential impact of low-dose BPA on altering the basic ability of aquatic organism in adapting to the surrounded complex environment still remains elusive. In this research, we report that treatment of adult male zebrafish with chronic (7 weeks) low-dose (0.22 nM-2.2 nM) BPA, altered the ability in adapting the complex environment by disturbing the natural color preference patterns. In addition, chronic 50 ng/L (0.22 nM) BPA exposure alleviated the anxiety behavior of male zebrafish confronted with the novel environment by enhancing the preference towards light in the light/dark preference test. This phenotype was associated with less expression of serotonin (5-TH) in the hypothalamus and the down-regulation of tyrosine hydroxylase (TH) in brain tissues. As such, our results show that low-dose BPA remnant in surface waters altered zebrafish behavior that are known to have ecological and evolutionary consequences., Highlights: Here we reported that the impact of chronic low-dose BPA exposure on the basic capability of zebrafish to adapt to the environmental complexity. Specifically, BPA at low concentration, under the environmental safety level and 3000-fold lower than the accepted human daily exposure, interfered with the ability to discriminate color and alleviate anxiety induced by the novel environment, which finally altered the capability of male zebrafish to adapt to the environmental complexity. These findings revealed the ecological effect of low-dose BPA and regular BPA concentration standard are not necessarily safe. The result also provided the consideration of retuning the hazard concentration level of BPA., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

Background: Treatment responses to methylphenidate by adults with ADHD are generally monitored against DSM-IV/DSM-V symptomatology, rating scales or interviews during reviews., Aims: To evaluate the use of single- and dual-dimension processing-speed and efficiency measures to monitor the effects of pharmacological treatment with methylphenidate after a short period off medication., Methods: A Quick Test of Cognitive Speed (AQT) monitored the effects of immediate-release methylphenidate in 40 previously diagnosed and medicated adults with ADHD. Processing speed was evaluated with prior prescription medication, without medication after a 2-day period off ADHD medication, and with low-dose (10/20 mg) and high-dose (20/40 mg) methylphenidate hydrochloride (Medikinet IR)., Results: Thirty-three participants responded to the experimental treatments. One-way ANOVA with post-hoc analysis (Scheffe) indicated significant main effects for single dimension colour and form and dual-dimension colour-form naming. Post-hoc analysis indicated statistical differences between the no- and high-dose medication conditions for colour and form, measures of perceptual speed. For colour-form naming, a measure of cognitive speed, there was a significant difference between no- and low-dose medication and between no- and high-dose medications, but not between low- and high-dose medications., Conclusions: Results indicated that the AQT tests effectively monitored incremental effects of the methylphenidate dose on processing speed after a 2-day period off medication. Thus, perceptual (colour and form) and cognitive speed (two-dimensional colour-form naming) and processing efficiency (lowered shift costs) increased measurably with high-dose medication. These preliminary findings warrant validation with added measures of associated behavioural and cognitive changes.

Zebrafish are increasingly used in neurobiological and behavioral studies. Possible stimuli to manipulate zebrafish behavior are being investigated. The presentation of colors appears to be one of the most used approaches, but there is much debate about the exact color preference. Here we have investigated the color preference in both larvae and adult zebrafish. We have studied the effects of wavelength, contrast, intensity, and location. Furthermore, we have tried to manipulate the preference with anxiolytic drugs (ethanol and buspirone). Our results show that both adults and larvae have a clear preference for blue zones while they avoid yellow-colored zones. Red and green zones have an intermediate preference. Part of the yellow aversion is caused by a fear for this color and can be diminished by the treatment with anxiolytic drugs. The location of the color appears to be of critical importance. Presentation of the color on the walls induces an approach response whereas presentation on the bottom induces an aversion. In conclusion, colors are important stimuli to manipulate zebrafish behavior and can be used in behavioral models. Standardization of the procedures and a clear description of the used methodologies are, however, essential.

An appropriate model to predict the effect of xenobiotics on the vision perception in neuropsychoharmacological studies is of great importance in drug development and toxicity studies. The present study valuated the effect of CNS stimulant, depressant and therapeutic agents known to have ocular toxicity on ptomotor response (OMR) using goldfish in a newly developed device. A digital light processing aided gyrating poly-chromatic dotted pattern-OMR (Gyro-dot-OMR) analyzer was developed and standardized for this study in our laboratory. Goldfishes were exposed to varying concentrations of caffeine and pentobarbitone sodium to evaluate the effect of CNS stimulation and depression on OMR in white light. Ethambutol induced ocular toxicity was evaluated by intravitreal injection into both eyes of goldfishes. They were subjected for polychromatic Gyro-dot-OMR in both clock and anticlockwise directions. At the low concentration (5, 10 and 20 ng/mL) caffeine exposed animals showed significant (p<0.05) stimulant effect and the EC(50) of caffeine in goldfish was found to be 4.806 ng/mL. In contrast, pentbbarbitone sodium treated fishes showed significant (p<0.05) depressant effect with increasing the concentration. Ethambutol toxicity was reflected by the color iscrimination in the Gyro-dot-OMR pattern. For the first time, this model proved the possibility of running Irwin profile test on goldfish using Gyro-dot-OMR. This model successfully predicted ethambutol induced toxicity with poor discrimination of red-green color. This model can be used for predicting toxicity of drugs affecting vision perception.

Studies of humans chronically exposed to volatile organic solvents have reported impaired visual functions, including low contrast sensitivity and reduced color discrimination. These reports, however, lacked confirmation from controlled laboratory experiments. To address this question experimentally, we examined visual function by recording visual evoked potentials (VEP) and/or electroretinograms (ERG) from four sets of rats exposed repeatedly to toluene. In addition, eyes of the rats were examined with an ophthalmoscope and some of the retinal tissues were evaluated for rod and M-cone photoreceptor immunohistochemistry. The first study examined rats following exposure to 0, 10, 100 or 1000ppm toluene by inhalation (6hr/d, 5d/wk) for 13 weeks. One week after the termination of exposure, the rats were implanted with chronically indwelling electrodes and the following week pattern-elicited VEPs were recorded. VEP amplitudes were not significantly changed by toluene exposure. Four to five weeks after completion of exposure, rats were dark-adapted overnight, anesthetized, and several sets of electroretinograms (ERG) were recorded. In dark-adapted ERGs recorded over a 5-log (cd-s/m(2)) range of flash luminance, b-wave amplitudes were significantly reduced at high stimulus luminance values in rats previously exposed to 1000ppm toluene. A second set of rats, exposed concurrently with the first set, was tested approximately one year after the termination of 13 weeks of exposure to toluene. Again, dark-adapted ERG b-wave amplitudes were reduced at high stimulus luminance values in rats previously exposed to 1000ppm toluene. A third set of rats was exposed to the same concentrations of toluene for only 4 weeks, and a fourth set of rats exposed to 0 or 1000ppm toluene for 4 weeks were tested approximately 1year after the completion of exposure. No statistically significant reductions of ERG b-wave amplitude were observed in either set of rats exposed for 4 weeks. No significant changes were observed in ERG a-wave amplitude or latency, b-wave latency, UV- or green-flicker ERGs, or in photopic flash ERGs. There were no changes in the density of rod or M-cone photoreceptors. The ERG b-wave reflects the firing patterns of on-bipolar cells. The reductions of b-wave amplitude after 13 weeks of exposure and persisting for 1year suggest that alterations may have occurred in the inner nuclear layer of the retina, where the bipolar cells reside, or the outer or inner plexiform layers where the bipolar cells make synaptic connections. These data provide experimental evidence that repeated exposure to toluene may lead to subtle persistent changes in visual function. The fact that toluene affected ERGs, but not VEPs, suggests that elements in the rat retina may be more sensitive to organic solvent exposure than the rat visual cortex., (Published by Elsevier B.V.)

Rationale: Prospective memory involves remembering to do something in the future and has a prospective component (remembering that something must be done) and a retrospective component (remembering what must be done and when it must be done). Initial studies reported an impairment in prospective-memory performance due to acute alcohol consumption. Retrospective-memory studies demonstrated that alcohol effects vary depending on the emotionality of the information that needs to be learned., Objectives: The aim of the present study was to investigate possible differential effects of a mild acute alcohol dose (0.4 g/kg) on the prospective and retrospective components of prospective memory depending on cue valence., Method: Seventy-five participants were allocated to an alcohol or placebo group and performed a prospective-memory task in which prospective-memory cue valence was manipulated (negative, neutral, positive). The multinomial model of event-based prospective memory (Smith and Bayen 2004) was used to measure alcohol and valence effects on the two prospective-memory components separately., Results: Overall, no main effect of alcohol or valence on prospective-memory performance occurred. However, model-based analyses demonstrated a significantly higher retrospective component for positive compared with negative cues in the placebo group. In the alcohol group, the prospective component was weaker for negative than for neutral cues and the retrospective component was stronger for positive than for neutral cues. Group comparisons showed that the alcohol group had a significantly lower prospective component for negative cues and a lower retrospective component for neutral cues., Conclusion: This is the first study to demonstrate selective alcohol effects on prospective-memory components depending on prospective-memory cue valence.

The zebrafish (Danio rerio) is a useful vertebrate model organism for neurological studies. While a number of behavior and learning assays are recently reported in the literature for zebrafish, many of these assays are still being refined. The initial purpose of this study was to apply a published T-maze assay for adult zebrafish that measures how quickly an organism can discriminate between different color stimuli after receiving reinforcement to measure learning in a study investigating the later life impacts of developmental Pb exposure. The original results were inconclusive as the control group showed a directional and color preference. To assess directional preference further, a three-chambered testing apparatus was constructed and rotated in several directions. The directional preference observed in males was alleviated by rotating the arms pointing west and east. In addition, color preference was investigated using all combinations of five different colors (orange, yellow, green, blue and purple). With directional preference alleviated results showed that both male and female zebrafish preferred colors of shorter wavelengths. An additional experiment tested changes in color preference due to developmental exposure to Pb in adult male zebrafish. Results revealed that Pb-exposed males gained and lost certain color preferences compared to control males and the preference for short wavelengths was decreased. Overall, these results show that consideration and pretesting should be completed before applying behavioral and learning assays involving adult zebrafish to avoid innate preferences and confounding changes in neurotoxicology studies and that developmental Pb exposure alters color preferences in adult male zebrafish., (Copyright © 2015 John Wiley & Sons, Ltd.)

Objective: The color is a psychophysical phenomenon, and much has been studied about its physical components. However, the psychological part is poorly investigated, except for the difference between genders in the literature shows that more men are color deficient than women. Dental students are trained to better understand the differences in color, so we became interested in studying whether psychological variables such as anxiety and depression and use of hormonal contraceptives may interfere with this ability. The aim of this in vitro study was to investigate if factors, such as, hormonal contraceptive use, depressive symptoms, anxiety and quality of life, influence on the ability of color discrimination of dental school students., Materials and Methods: Sixty-one subjects participated and the following instruments apply: (1) test that consists in the observation of a set of 25 labels (Pantones) with values of known colors, (2) scales of depression, anxiety, and quality of life assessments, and (3) Ishihara test., Results: No difference was observed between genders as color perception (p = 0.868). Symptoms of anxiety and depression were significantly more frequent in the female population that showed worse quality of life (p < 0.000) but did not interfere with color perception. Women using hormonal contraceptives had lower color perception than men (p = 0.04)., Conclusion: No difference between the genders in the perception of colors was observed, contrary to common sense that women discriminate more colors than men, but women using hormonal contraceptives showed more difficulty in color perception., Clinical Significance: The ability to understand and distinguish color differences is extremely important in clinical dentistry. There could be differences in color perception between men and women that would influence clinical performance., (© 2014 Wiley Periodicals, Inc.)

Aim: To examine ocular findings of breast cancer patients using tamoxifen., Methods: The records of 79 consecutive breast cancer patients were examined, retrospectively. Female patients who had previously been diagnosed to have breast cancer with either stage I, II, or III disease, and were older than 25 years of age were included in the study. Results of the ophthalmic examination, color discrimination, and contrast sensitivity tests were recorded. Short wavelength automated perimetry (SWAP) sensitivity values were obtained, and average sensitivity values of test points at 5°, 9°, 15°, and 21° from the fixation were calculated., Results: Forty-nine of the patients had received 20 mg daily dose of tamoxifen therapy (tamoxifen group), while remaining 30 patients had not used tamoxifen (control group). Anterior and posterior segment examination revealed no pathologic findings in both groups. Two patients (5%) in the tamoxifen group had diffuse color loss, while none did in the control group (p = 0.523). Statistically significant differences were not detected between two groups when square roots of total error in color vision, red-green, and blue-yellow partial error scores were compared. Contrast sensitivity values were similar in both groups. Average mean deviation (MD) and average sensitivity values of test points at each 4° were statistically significantly lower in the tamoxifen group than the control group (p = 0.002, p = 0.001, p < 0.001 and p < 0.001 for right eye; p = 0.002, p= 0.001, p < 0.001 and p < 0.001 for left eye). Strong correlation was detected between MD, and duration (r = -0.832 and r = -0.842 for right and left eyes, respectively) and cumulative dose of tamoxifen use (r = -0.864 and r = -0.854 for right and left eyes, respectively)., Conclusion: Clinically significant ocular toxicity is not frequently encountered in breast cancer patients, however, SWAP changes may occur early after tamoxifen utilization.

We investigated the influence of intermittent normobaric hypoxia of sanogenic varying levels on the latent period of a complex visual-motor reaction in terms of choice in children - residents of radioactive contaminated territories. Indicators of anxiety were assessed with Spielberg - Hanin test. The study involved 48 children aged 6 to 17 years. The children were divided into two groups: the first one included the group from 6 to 11 years, and the second group from 12 to 17 years. It is shown that the intermittent normobaric hypoxia course sessions (12% O2 in nitrogen) reduced the latent period of complex visual-motor response of one of three colors (RC(1-3)) choice--23 % and complex visual-motor response of two of the three colors (RC(2-3)) choice--27%. It was revealed that the latent period RC(1-3) lasts longer than the latent period RC(2-3). The boys in both cases tend to have more rapid response than girl. It was found that after the sessions of varying normobaric hypoxia personal anxiety in both groups of children decreased by 20 and 23% respectively.

Purpose: Past studies have shown that higher macular pigment optical density (MPOD) and lutein (L) and zeaxanthin (Z) supplementation are related to improvements in glare disability, photostress recovery, and chromatic contrast. This study assessed those links using a randomized, double-blind, placebo-controlled design., Methods: The visual effects of 1 year of supplementing L (10 mg/d) and Z (2 mg/d) were investigated. One hundred fifteen young, healthy subjects were recruited and randomized into the study (58 received placebo, 57 L+Z). Several dependent measures were collected at baseline and then once every 3 months: serum L and Z measured by HPLC chromatography; MPOD measured using customized heterochromatic flicker photometry; photostress recovery assessed by measuring the time needed to recover visual acquisition of a grating target after 30 seconds of an intense xenon white flash exposure; glare disability evaluated as the energy in a surrounding annulus necessary to veil a central grating target; and chromatic contrast assessed by measuring thresholds for a yellow grating target superposed on a 460-nm background., Results: Macular pigment optical density increased significantly versus placebo at all eccentricities (10, 30, 60, and 105 minutes from the center of the macula). Serum L and Z also increased significantly by the first follow-up visit (at 3 months), and remained elevated throughout the intervention period of 1 year. Chromatic contrast and photostress recovery time improved significantly versus placebo. Glare disability was correlated with macular pigment density throughout the study period but did not increase significantly in the treated group., Conclusions: Daily supplementation with L+Z resulted in significant increase in serum levels and MPOD and improvements in chromatic contrast and recovery from photostress. These results are consistent with past studies showing that increasing MPOD leads to improved visual performance. (ClinicalTrials.gov number, NCT00909090.)., (Copyright 2014 The Association for Research in Vision and Ophthalmology, Inc.)

The effects of alcohol on pre-attentive processing have been well studied in the past decades. However, the majority of studies focus on pre-attentive auditory processing and only a few studies have examined the effects of alcohol on visual processing. This study investigates the effects of alcohol on automatic pre-attentive processing of visual changes in colour, location and duration. We compared the mean amplitudes and the amplitude decline ratios of visual mismatch negativity (vMMN) responses elicited for small and large changes in image colour, location and duration in 12 individuals under the influence of alcohol and in a placebo condition. The vMMN amplitudes for changes in location and duration significantly decreased in the alcohol condition as compared with the placebo condition, and the magnitude of decrease was not related to the magnitude of change in the deviant stimuli. However, the amplitude of colour vMMN, in the alcohol condition, did not change significantly compared to the placebo condition. These results show that pre-attentive visual processing is impaired by alcohol, and that this impairment may be feature-specific. In addition, this impairment was not related to the magnitude of stimuli change., (© The Author(s) 2014.)

Introduction: The metabolism of alcohol and cognitive functions can vary during the menstrual cycle. Also, both alcohol ingestion and hormonal variations during menstruation have been associated with characteristic changes in electroencephalographic (EEG) activity. AIM. To determine whether EEG activity during a working memory task is affected by acute alcohol consumption, and if these EEG patterns vary in relation to different phases of the menstrual cycle., Subjects and Methods: 24 women who drank a moderate dose of alcohol or placebo during the follicular and early luteal phases of the menstrual cycle. The EEG activity was recorded during performance of viso-spatial working memory task., Results: Although the alcohol did not deteriorate the performance of working memory task, it caused in the EEG a decrease of relative theta power and lower right fronto-parietal correlation in theta and alpha2 bands. Only women who drank alcohol in the follicular phase had a higher relative potency of alpha1, which could indicate a lower level of arousal and attention., Conclusions: These results contribute to a better understanding of the brain mechanisms underlying cognitive changes with alcohol and its relationship to the menstrual cycle.

Objectives: Antidepressants, among the most commonly prescribed medications, trigger symptoms of REM sleep behavior disorder (RBD) in up to 6% of users. Idiopathic RBD is a very strong prodromal marker of Parkinson disease and other synuclein-mediated neurodegenerative syndromes. It is therefore critically important to understand whether antidepressant-associated RBD is an independent pharmacologic syndrome or a sign of possible prodromal neurodegeneration., Design: Prospective cohort study., Setting: Tertiary sleep disorders center., Participants: 100 patients with idiopathic RBD, all with diagnosis confirmed on polysomnography, stratified to baseline antidepressant use, with 45 matched controls., Measurements/results: Of 100 patients, 27 were taking antidepressants. Compared to matched controls, RBD patients taking antidepressants demonstrated significant abnormalities of 12/14 neurodegenerative markers tested, including olfaction (P = 0.007), color vision (P = 0.004), Unified Parkinson Disease Rating Scale II and III (P < 0.001 and 0.007), timed up-and-go (P = 0.003), alternate tap test (P = 0.002), Purdue Pegboard (P = 0.007), systolic blood pressure drop (P = 0.029), erectile dysfunction (P = 0.002), constipation (P = 0.003), depression indices (P < 0.001), and prevalence of mild cognitive impairment (13% vs. 60%, P < 0.001). All these abnormalities were indistinguishable in severity from RBD patients not taking antidepressants. However, on prospective follow-up, RBD patients taking antidepressants had a lower risk of developing neurodegenerative disease than those without antidepressant use (5-year risk = 22% vs. 59%, RR = 0.22, 95%CI = 0.06, 0.74)., Conclusions: Although patients with antidepressant-associated RBD have a lower risk of neurodegeneration than patients with "purely-idiopathic" RBD, markers of prodromal neurodegeneration are still clearly present. Development of RBD with antidepressants can be an early signal of an underlying neurodegenerative disease.

As with mosquitoes, female tabanid flies search for mammalian hosts by visual and olfactory cues, because they require a blood meal before being able to produce and lay eggs. Polarotactic tabanid flies find striped or spotted patterns with intensity and/or polarisation modulation visually less attractive than homogeneous white, brown or black targets. Thus, this reduced optical attractiveness to tabanids can be one of the functions of striped or spotty coat patterns in ungulates. Ungulates emit CO2 via their breath, while ammonia originates from their decaying urine. As host-seeking female tabanids are strongly attracted to CO2 and ammonia, the question arises whether the poor visual attractiveness of stripes and spots to tabanids is or is not overcome by olfactory attractiveness. To answer this question we performed two field experiments in which the attractiveness to tabanid flies of homogeneous white, black and black-and-white striped three-dimensional targets (spheres and cylinders) and horse models provided with CO2 and ammonia was studied. Since tabanids are positively polarotactic, i.e. attracted to strongly and linearly polarised light, we measured the reflection-polarisation patterns of the test surfaces and demonstrated that these patterns were practically the same as those of real horses and zebras. We show here that striped targets are significantly less attractive to host-seeking female tabanids than homogeneous white or black targets, even when they emit tabanid-luring CO2 and ammonia. Although CO2 and ammonia increased the number of attracted tabanids, these chemicals did not overcome the weak visual attractiveness of stripes to host-seeking female tabanids. This result demonstrates the visual protection of striped coat patterns against attacks from blood-sucking dipterans, such as horseflies, known to transmit lethal diseases to ungulates., (© 2013.)

Aims: To report the first three studies with SCH 900435, a selective glycine-1 re-uptake inhibitor in development for treating schizophrenia, using systematic evaluations of pharmacodynamics to understand the observed effects., Methods: Three double-blind, placebo-controlled studies (single, visual effect and multiple dose) were performed. In the single and multiple dose study SCH 900435 (0.5-30 mg) was given to healthy males and frequent pharmacokinetic and pharmacodynamic measurements were performed. The visual effects study incorporated visual electrophysiological measures of macular, retinal and intracranial visual pathway function., Results: In the single dose study (highest difference, 95% CI, P) increases in smooth pursuit eye movements (8, 12 mg (-6.09, 10.14, -2.04, 0.013), 30 mg), pupil : iris ratio (20 and 30 mg (-0.065, 0.09, -0.04, <0.0001)), VAS colour perception (30 mg (-9.48, 13.05, -5.91, <0.0001)) and changes in spontaneous reports of visual disturbance were found, while FSH (8 mg (0.42, 0.18, 0.66, 0.0015), 12, 20 mg), LH (8-30 mg (1.35, 0.65, 2.05, 0.0003)) and EEG alpha2 activity decreased (12, 20, 30 mg (0.27, 0.14, 0.41, 0.0002)). A subsequent dedicated visual effects study demonstrated that visual effects were transient without underlying electrophysiological changes. This provided enough safety information for starting a multiple ascending dose study, showing less visual symptoms after twice daily dosing and titration, possibly due to tolerance., Conclusions: Several central nervous system (CNS) effects and gonadotropic changes resulted from administration of 8 mg and higher, providing evidence for CNS penetration and pharmacological activity of SCH 900435. Antipsychotic activity in patients, specificity of the reported effects for this drug class and possible tolerance to visual symptoms remain to be established., (© 2012 Centre for Human Drug Research. British Journal of Clinical Pharmacology © 2012 The British Pharmacological Society.)

Objective: This retrospective study used a quick test of cognitive speed (AQT) processing-speed and efficiency measures for evaluating sensitivity and monitoring effects during pharmacological treatment of adults with ADHD., Method: Color (C), form (F), and color-form (CF) combination naming were administered to 69 adults during outpatient evaluation, and pre- and posttreatment results were compared for 64 adults., Results: At intake without medication, naming times (s) were significantly longer and overhead, CF - (C + F), larger than after stabilization of ADHD symptoms. Means for single-dimension naming were in the normal range, and for CF and overhead, means were in the atypical ranges. After treatment, CF and overhead improved to within normal ranges. On average, dual-dimension processing speed increased by 31% and efficiency by 73%. Sensitivity at intake was 91%, using fail-criteria for CF and/or overhead., Conclusion: Results support previous estimates of sensitivity and ability to monitor pharmacological-treatment effects in ADHD.

Aims: To study whether morphologic (foveal thickness, FT) variations of clinically significant macular oedema (CMO) in patients suffering from diabetes following intravitreal pegaptanib sodium (IVP) injection were associated with functional [macular sensitivity (MS) and colour discrimination (CD)] changes., Methods: A longitudinal, interventional, non-randomized study was performed. FT was assessed by optical coherence tomography (OCT), MS by microperimetry, best-corrected visual acuity (BCVA) by early treatment diabetic retinopathy study charts (ETDRS) and CD by Farnswoth-Munsell test. The treatment protocol consisted of three consecutive injections (0.3 mg/0.05 ml; baseline, week 6 and week 12). Follow-up checks were scheduled at 18, 24, 36 and 48 weeks, after injections., Results: Thirty eyes of 30 patients with clinically significant CMO were included for analysis. After IVP a significant decrease of FT occurred with a mean reduction from baseline of 56.9% (P= 0.0001). An improvement of functional parameters was recorded in all patients (BCVA from 18.2 ± 8.5 letters to 25.5 ± 8.4 letters, P < 0.005, MS from 8.6 ± 2.16 dB to 10.6 ± 2.61 dB, P < 0.001, colour analysis from 376.1 ± 125.6 TES to 116 ± 34.6 TES, P= 0.0001). A statistically significant correlation between FT and BCVA as well as MS and CD was also found. Neither ocular nor systemic adverse events were reported., Conclusions: Intravitreal pegaptanib significantly reduced FT, with a concomitant improvement of MS and CD. This association emphasizes the efficacy of IVP in the treatment of CMO., (© 2012 The Authors. British Journal of Clinical Pharmacology © 2012 The British Pharmacological Society.)

Neuropsychological investigations of patients with Parkinson's disease, schizophrenia, or attention deficit disorder converge with psychopharmacological studies in animals and healthy volunteers to implicate dopamine (DA) pathways in timing. In parallel, single-cell recording and functional neuroimaging studies have highlighted the importance of basal ganglia, prefrontal cortex, and supplementary motor area (SMA) for timing. In a placebo-controlled, within-subject design, we combined event-related functional magnetic resonance imaging with a DA manipulation (acute phenylalanine/tyrosine depletion; APTD) in healthy volunteers to pinpoint the neuroanatomical and functional substrates of the DA modulation of timing. Behaviorally, APTD selectively impaired accuracy of perceptual timing, with no effect on performance of a color-control task matched for difficulty, working memory (WM), and attentional demands. Neurally, APTD attenuated timing-specific activity in the putamen and SMA. Notably, APTD-induced decreases in brain activity were directly correlated to APTD-induced impairments in timing performance. Moreover, APTD modulated timing-specific activity selectively during initial storage of the sample duration, but had no effect during its subsequent retrieval or comparison to a probe. Our results do not simply reflect DA modulation of WM since the color task controlled for the WM updating process necessary for timing of durations in the seconds range. Moreover, preliminary evidence indicated APTD effects on putamen and SMA were greater for subsecond (540 ms) than suprasecond (1080 ms) durations, when WM demands would actually be lower. Instead, we show for the first time in healthy humans that DA manipulation perturbs timing by attenuating the activity in putamen and SMA that mediates initial storage of temporal information into WM.

Background: In recent years, small-scale clinical trials have indicated that statins or 3-hydroxy-3-methylglutaryl coenzyme A (HMGCoA) reductase inhibitors exert pleiotropic immunomodulatory effects, with potential therapeutic implications in multiple sclerosis (MS)., Objective: To investigate whether simvastatin treatment (80 mg daily for 6 months) in patients with optic neuritis (ON) had a beneficial effect on visual outcome and on brain MRI., Methods: Sixty-four patients with acute ON were randomized to simvastatin treatment (n = 32) or placebo (n = 32) for 6 months. None of the patients had been on immunosuppressive therapy for 6 months prior to inclusion or treated with steroids from symptom onset. Contrast sensitivity (Arden plates), visual acuity, colour perception, visual evoked potentials (VEP)--latency and amplitude, Visual Analogue Scale (VAS) score, and gadolinium enhancing and T2 lesions on brain MRI were evaluated at screening visit, day 14 (except brain MRI), day 90 and day 180., Results: Simvastatin had a beneficial effect on VEP in both latency (p = 0.01) and amplitude (p = 0.01), a borderline effect on the Arden score (p = 0.06) and VAS (p = 0.04), and no effect on brain MRI or on relapse rate between the groups., Conclusion: This study provides Class I evidence that simvastatin 80 mg daily is well tolerated and possibly effective in patients with acute ON.

Rationale: Disturbances in the subjective experience of time have been observed both in schizophrenia and following acute administration of ketamine. However, effects of ketamine on more objective timing tasks have not yet been measured in humans, nor has it been established that timing effects are not merely secondary to a more general dysfunction in working memory (WM)., Objective and Methods: In a double-blind placebo-controlled crossover study, we characterised the effects of ketamine (100 ng/ml blood plasma level) on performance of perceptual timing and colour discrimination tasks, which were matched for WM and attentional demands. To test the ubiquity of ketamine's effects on timing, we also examined two distinct measures of temporal predictability., Results: Ketamine significantly distorted the subjective experience of time as measured by the Clinician-Administered Dissociative States Scales. Critically, ketamine also impaired accuracy on the perceptual timing task while having no effect on performance of the colour perception task. Although ketamine did not impair the ability to use prelearned temporal (or spatial) cues to predict target onset (or location), it did slow reaction times at long delays following non-informative neutral cues, suggesting an impaired ability to use the unidirectional flow of time itself to make temporal predictions., Conclusions: Ketamine induced selective impairments in timing, which could not be explained by more fundamental effects on the ability to hold information in WM. Rather our collected findings suggest that ketamine may disturb timing by selectively impairing the way in which information is temporally manipulated within WM.

Purpose: The purpose of this study was to investigate the dose-dependent effects of propofol on cognitive function and muscle power as well as vital functions., Materials and Methods: Twenty volunteers participated in this study. Each subject underwent 2 experiments in a randomized crossover manner (propofol group and control group). After control data were obtained, propofol at predicted effect site concentrations of 0.4, 0.8, 1.2, 1.6, and 2.0 μg/mL was infused in the propofol group using a target controlled infusion system. Heart rate, noninvasive blood pressure, arterial oxygen saturation, respiratory rate, and bispectral index value were monitored. Observer's assessment of alertness/sedation and the correct answer rate of the Stroop color word test were assessed. Muscle power, grip strength and bite force were measured., Results: In the propofol group, the bispectral index value and observer's assessment of alertness/sedation scale dose-dependently reduced. At the predicted effect site propofol concentration of 2.0 μg/mL, 6 subjects became unconscious. The correct answer rate of Stroop color word test reduced at the predicted effect site propofol concentration of 1.6 and 2.0 μg/mL. Grip strength slightly increased at the predicted effect site propofol concentration of 1.2 μg/mL or less, and bite force dose-dependently increased. At the predicted effect site propofol concentration of 2.0 μg/mL, both muscle powers began to decrease. Bite force dose-dependently increased and reached the maximum at the predicted effect site propofol concentration of 1.6 μg/mL., Conclusion: Although the detailed mechanisms are unknown, propofol dose-dependently increases bite force during minimal and moderate sedation., (Copyright © 2011 American Association of Oral and Maxillofacial Surgeons. Published by Elsevier Inc. All rights reserved.)

Purpose: The purpose of the study was to examine possible persisting effects to color vision in a group from the Royal Australian Air Force who had exposure to formulations containing neurotoxins during F-111 fuel tank maintenance, relative to two contemporaneous comparison groups., Methods: Color vision was tested in 512 exposed personnel, 458 technical-trade comparisons, and 330 non-technical comparisons using the Ishihara test plates and the Lanthony D-15 Desaturated Color disk arrangement test. Participants were excluded if they failed the Ishihara test as this indicates congenital color blindness. From the Lanthony results, the type of color deficient vision (CDV) was diagnosed, and additionally, the Bowman's color confusion index (CCI) was calculated. Regression models were used to examine whether there was an association between color vision deficiencies and F-111 fuel tank maintenance, adjusting for possible confounders., Results: The CCI ranged from 1 to 2.8 (median 1.2, quartiles 1.1, 1.4) in the 2,600 eyes tested. Forty five percent of all participants had blue-yellow CDV in at least one eye. Deficiencies of this nature are caused by environmental exposures. Logistic regression demonstrated statistically significant differences in CCI category in the exposed group versus technical group (odds ratio 1.7: 95% CI 1.3-2.0) and a blue-yellow confusion in the exposed group versus technical group (odds ratio 1.4: 95% CI 1.1-1.7). No differences were observed between the exposed group and the non-technical group., Conclusion: The results indicate reduced color discrimination among the exposed subjects compared to one of two control groups. The findings may be due to previous exposure to solvents among the air force personnel.

Purpose: The purpose of this study was to conduct a questionnaire-based survey of subjective visual perceptions induced by intravitreous (IVT) injections of therapeutic agents., Patients and Methods: Patients undergoing an IVT injection of ranibizumab, pegaptanib sodium, or triamcinolone acetonide were administered a questionnaire in the immediate post-injection period and at 2 weeks of follow-up., Results: In the immediate post-injection period (75 IVT injections, 75 eyes, 75 patients), lights and floaters were reported after 20 (27%) and 24 (32%) IVT injections, respectively. In comparison, at the 2-week follow-up, the incidence of reported lights (11; 15%) was similar (P>0.05), but the incidence of reported floaters was higher (48; 64%; P=0.00). Subgroup analysis for various injection subgroups (no previous injection vs previous injection(s) in the study eye; injections in study eyes with good VA (logarithm of minimal angle of resolution [logMAR] ≤ 0.3) vs moderate VA (0.7 0.3) vs poor VA (logMAR ≥ 0.7); injections according to pharmacological agent (ranibizumab vs pegaptanib vs triamcinolone acetonide); injections in study eyes with choroidal neovascularization (of various causes) vs study eyes with macular edema (of various causes); and injections in phakic vs pseudophakic eyes) did not reveal any statistically significant associations. Visual perceptions experienced following 15% of IVT injections gave cause for concern to the patient (mean visual analog scale score (± SD): 4.5 (± 1.7)), and in 64% of cases, the patients believed that preoperative counseling would have averted the concern., Conclusions: Lights and floaters are frequent visual perceptions following IVT injections of therapeutic agents. They can give rise to concern that could be alleviated with preinjection counseling.

Introduction: Acquired reversible dyschromatopsia has been associated with occupational exposure to mercury vapor. Early-detected impairments in color discrimination precede adverse permanent effects of mercury, so they may help to monitor the health of the exposed workers. The aim of this study was to evaluate the color discrimination ability in this group of workers, using Lanthony D-15d test., Material and Methods: Employed in a chloralkali plant, 27 male workers exposed to mercury vapor and 27 healthy white-collar workers (control group) were qualified for the study. To assess color discrimination, the Lanthony 15-Hue desaturated test (Lanthony D-15) was used. In order to investigate quantitative and qualitative results, the Lanthony D-15d scoring software was performed. Urinary mercury was determined using flameless atomic absorption spectrometry., Results: In the workers exposed to mercury vapor, urine mercury concentration was 117.4 +/- 62.6 microg/g creatinine on average compared with 0.279 +/- 0.224 mg/g creatinine in the control group (p < 0.0001). In 18 exposed persons (66.7%), the results of the Lanthony D-15d test showed qualitative changes, which are borderline corresponding to the early stage of developing dyschromatopsia type III. The quantitative analysis of the test findings indicated a significantly higher value of the Color Confusion Index (CCI) in the right eye in the exposed group compared to the control group (p = 0.01), with no significant difference in the CCI in the left eye. In the exposed group, the CCI in the right eye was significantly higher than the CCI in the left eye (p = 0.0005). There was neither correlation between CCI and the level of urinary mercury, nor between CCI and duration of exposure., Conclusions: The results showed that the Lanthony D-15d test is useful in the detection of early toxic effects in the eyesight of the workers exposed to mercury vapor. The observed color vision impairments are borderline corresponding to the early stage of developing dyschromatopsia type III.

Eight high-potency heavy cannabis smokers who fulfilled DSM-IV-TR criteria for cannabis dependence sought treatment for outpatient detoxification. During routine psychiatric interview they reported the presence of visual disturbances when intoxicated and no prior history of LSD use. They all communicated the persistence of visual disturbances after ceasing cannabis use. Seven categories of visual disturbances were described when staring at stationary and moving objects: visual distortions, distorted perception of distance, illusions of movement of stationary and moving objects, color intensification of objects,dimmed color, dimensional distortion and blending of patterns and objects. Patients reported having 2-5 different categories of flashbacks up to 3-6 months after cessation of cannabis use. The described phenomena may be interpreted as a time-limited benign side effect of high-potency cannabis use in some individuals. A combination of vulnerability and use of large amounts of high potency cannabis seem to contribute to the appearance of this condition. Conclusions from uncontrolled case series should be taken with appropriate caution.

The purpose of this study is to examine the effects of various levels of alcohol consumption on human response to auditory and visual stimuli in terms of reaction time, movement time, total reaction time, and error rate. Placebo level and three low-level alcohol doses were randomly assigned to 20 male university student volunteers. 30 min. after consuming the alcohol or placebo, participants responded to either auditory or visual stimuli. Total reaction time increased significantly at the mid-low dose of alcohol (0.3 g/kg). For alcohol doses less than .5 g/kg, the change in total reaction time was confined to reaction time, i.e., the processing time between onset of stimulus and onset of movement. Effects of alcohol were significantly more pronounced in the choice-type tests. Notably, the effects of alcohol on total reaction time and error rate were significant for auditory but not visual stimuli.

Objective: To evaluate the impact of clomiphene citrate on vision., Design: Observational study., Setting: Patients were referred to the University of Ottawa Eye Institute ophthalmology clinic from the Department of Obstetrics and Gynaecology of the Ottawa Hospital-General Campus., Patient(s): Eight adult females taking clomiphene citrate and experiencing visual disturbances., Intervention(s): Patients received a comprehensive visual evaluation twice: once during a washout period, and once during an active clomiphene citrate treatment., Main Outcome Measure(s): Ophthalmologic examination, color vision, visual acuity, contrast sensitivity, visual fields using standard automated perimetry, and foveal flicker sensitivity at high (32 Hz) and low (8 Hz) temporal frequencies., Result(s): We found no differences between the washout and clomiphene citrate conditions for color vision, visual acuity, contrast sensitivity, and visual fields. The only statistically significant difference was found for foveal flicker sensitivity at 32 Hz in the right eye, with a similar trend in the left eye and at 8 Hz in both eyes., Conclusion(s): The effect of clomiphene citrate on vision was minimal, and the visual disturbances were reversible in all patients. A bilateral reduction in flicker sensitivity was the only observed visual disturbance. Women who experience visual symptoms associated with clomiphene citrate should be monitored, but therapy can usually be maintained., (Copyright 2010 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.)

Objective: To evaluate whether there are visual and neuropsychological decrements in workers with low exposure to Hg vapor., Methods: Visual fields, contrast sensitivity, color vision, and neuropsychological functions were measured in 10 workers (32.5 +/- 8.5 years) chronically exposed to Hg vapor (4.3 +/- 2.8 years; urinary Hg concentration 22.3 +/- 9.3 microg/g creatinine)., Results: For the worst eyes, we found altered visual field thresholds, lower contrast sensitivity, and color discrimination compared with controls (P <0.05). There were no significant differences between Hg-exposed subjects and controls on neuropsychological tests. Nevertheless, duration of exposure was statistically correlated to verbal memory and depression scores., Conclusions: Chronic exposure to Hg vapor at currently accepted safety levels was found to be associated with visual losses but not with neuropsychological dysfunctions in the sample of workers studied.

This longitudinal study evaluated whether the level of intrauterine cocaine exposure (IUCE) or the interaction between IUCE and contextual variables was related during middle childhood to executive functioning, as assessed with the Stroop Color-Word and Rey Osterrieth Complex Figure tests. The Stroop Interference score measures verbal inhibitory control while the Rey Osterrieth Organizational score evaluates skills such as planning, organization and perception. Masked examiners assessed 143 children at 9.5 and 11 years of age (74 with IUCE and 69 demographically similar children without IUCE). Level of IUCE (Unexposed; Lighter, and Heavier) was documented by positive postpartum maternal reports and infant meconium assays. In covariate-controlled regressions, level of IUCE was not significantly associated with Stroop Interference or Rey Osterrieth Organization scores. However, in covariate controlled post-hoc tests comparing the Heavier exposed group to the combined Lighter/Unexposed group, children in the Heavier group had significantly poorer Stroop Interference scores, but there was no significant group difference for Rey Osterrieth Organizational scores. Children's average Organization scores in Unexposed, Lighter, and Heavier exposed groups were well below the test norm means. Results of this study indicate that heavier IUCE may be associated with mild compromise on school-aged children's ability to inhibit prepotent verbal responses.

Recent reports of selective disruption of stimulus control by drug administration and other disruptive operations in temporal discrimination procedures may be interpreted as a disruption of attention to the temporal sample stimuli. This experiment assessed the effects of nicotine, a compound that has been widely shown to increase measures of attention, on temporal discrimination performance. Pigeons responded under a psychophysical choice procedure in which responses to one key color were correct after presentation of four shorter sample durations and responses to another key color were correct after presentation of four longer sample durations. Performance under nicotine was characterized by using a model that differentiates the effects of nicotine on stimulus control, bias, and sensitivity of temporal discrimination. Nicotine selectively decreased the measure of stimulus control, but did not systematically affect the measures of timing. Mecamylamine (1.0 mg/kg) failed to antagonize the disruptive effects of nicotine. These results suggest that disruption of temporal discrimination performance in this preparation may not have been dependent on the specific pharmacology of nicotine and underscore the importance of quantitative separation of the effects of various manipulations on stimulus control from effects on timing.

This longitudinal study addresses the reversibility of color vision losses in subjects who had been occupationally exposed to mercury vapor. Color discrimination was assessed in 20 Hg-exposed patients (mean age = 42.4 +/- 6.5 years; 6 females and 14 males) with exposure to Hg vapor during 10.5 +/- 5.3 years and away from the work place (relative to 2002) for 6.8 +/- 4.2 years. During the Hg exposure or up to one year after ceasing it, mean urinary Hg concentration was 47 +/- 35.4 mug/g creatinine. There was no information on Hg urinary concentration at the time of the first tests, in 2002 (Ventura et al., 2005), but at the time of the follow-up tests, in 2005, this value was 1.4 +/- 1.4 microg/g creatinine for patients compared with 0.5 +/- 0.5 microg/g creatinine for controls (different group from the one in Ventura et al. (2005)). Color vision was monocularly assessed using the Cambridge Colour Test (CCT). Hg-exposed patients had significantly worse color discrimination (p < 0.02) than controls, as evaluated by the size of MacAdam's color discrimination ellipses and color discrimination thresholds along protan, deutan, and tritan confusion axes. There were no significant differences between the results of the study in Ventura et al. (2005) and in the present follow-up measurements, in 2005, except for worsening of the tritan thresholds in the best eye in 2005. Both chromatic systems, blue-yellow and red-green, were affected in the first evaluation (Ventura et al., 2005) and remained impaired in the follow-up testing, in 2005. These findings indicate that following a long-term occupational exposure to Hg vapor, even several years away from the source of intoxication, color vision impairment remains irreversible.

Background: Bevacizumab (Avastin) has been used as off-label treatment for the specific inhibition of the vascular endothelial growth factor (VEGF). Although only intravenous administration of the drug is approved in combination therapy of colorectal carcinoma, promising short-term results have been reported about its intravitreal administration. However, VEGF is also known to exhibit neurotrophic capabilities. Therefore, blockage of all VEGF isoforms by bevacizumab could induce toxic effects. Missing randomized controlled studies and unclear long-term risks require further evaluation., Methods: Intensified monitoring of bevacizumab treatment was performed in consecutive patients. In ten patients, the functional field score was calculated after obtaining Goldmann visual fields at baseline and 1 year after injection. The other subgroup was examined by means of EOG, ERG and colour testing at baseline and 4 months following treatment. Naka-Rushton plots were calculated to enable statements about retinal function. Lanthony desaturated D15 test was used for repeated colour testing., Results: Baseline parameters already disclosed predominant cone dysfunction. Drug-related effects caused a significant improvement of visual acuity. There was no sign of clinically relevant retinal toxicity following the bevacizumab injection. No progression of visual field defects was seen within the follow-up of 1 year. Performance in EOG testing was affected by restricted fixation stability, but no parameter indicated deterioration within the 4-month-period., Conclusions: Short-term results underline that intraocular bevacizumab injection promises to be not only a cost-effective, but safe treatment option. Assessed functional parameters as error scores (e.g., Lanthony) corresponded to the impaired retinal function which was presumed to be disease-related. Further long-term results have to confirm the good tolerability in repeated treatment.

Introduction: Norepinephrine (NE) has a regulatory role in human attention., Objective: To examine its role in emotional modulation of attention, we used an attentional blink (AB) paradigm, in the context of psychopharmacological manipulation, where targets were either emotional or neutral items., Results and Discussion: We report behavioural evidence that beta-adrenergic blockade with propranolol impairs attention independent of target valence. Furthermore, this effect is centrally mediated as administration of the peripheral beta-adrenergic antagonist nadolol did not impair attention. By contrast, increasing NE tone, using the selective NE reuptake inhibitor reboxetine, improves detection of emotional stimuli., Conclusion: In line with theoretical and animal models, these findings provide human behavioural evidence that the adrenergic system has a modulatory influence on selective attention that in some instances depends on item valence.

Background: Hepatitis C virus and interferon treatment have been associated with retinopathy. Baseline and ongoing assessment by ophthalmologists have therefore been advocated in previous studies. Our experience suggests that the incidence is low, with no or negligible impact of pegylated interferon alpha on actual visual function. This study was conducted to determine whether ophthalmic assessment is necessary in such patients., Methods: The study was a prospective case series of 52 patients (104 eyes). Visual acuity, contrast sensitivity, colour vision, visual field by perimetry and fundal assessment were measured at baseline and at 3 and 6 months post commencement of interferon alpha treatment., Results: Forty-two men and ten women were followed. No patients reported any subjective visual symptoms. The mean changes in right and left logarithmic minimal angle resolution (LogMAR) visual acuity were negligible between baseline and 6 months (0.05 (SD 0.13) and 0.10 (SD 0.12), respectively). Mean changes in contrast sensitivity and colour vision were also negligible. Of all eyes monitored by serial perimetry for the full follow-up period and deemed to have reliable tests, none developed visual field defects. One patient appeared to develop nasal field defects within 3 months of commencing treatment but failed to attend for repeat testing. No patients developed optic disc changes or permanent fundal changes over the follow-up period., Conclusion: In contrast to previous studies in America and south-east Asia, our findings based on a UK cohort suggest that routine ophthalmic screening is not essential for patients with hepatitis C treated with pegylated interferon alpha who have no subjective visual complaints.

Objectives: The aim of the study was to examine possible persisting visual system effects in tunnel workers previously exposed to acrylamide and N-methylolacrylamide during grouting work., Material and Methods: Visual field light sensitivity threshold and colour vision has been examined among 44 tunnel workers 2-10 years after exposure to acrylamide and N-methylolacrylamide containing grouting agents. Forty-four tunnel workers not involved in grouting operations served as control group. Information on exposure and background variables was obtained for all participants from a questionnaire. Visual light sensitivity threshold was measured using Humphrey Visual Field Static Perimeter 740, program 30-2 Fastpack, with red stimuli on white background, and colour vision, using Lanthony D-15 Desaturated Color test. Based on D-15d test results, colour confusion index (CCI), and a severity index (C-index) was calculated., Results: The exposed group had a significantly higher threshold for detecting single stimuli in all parts of the inner 30 degrees of the visual field compared to the control group. The foveal threshold group difference was 1.4 dB (p=0.002) (mean value, both eyes). On the Lanthony 15 Hue Desaturated test, the exposed subjects made more errors in sorting blue colours, and a statistically significant increase in C-index was observed. Surrogate measures for duration and intensity of exposure gave no further improvement of the model., Conclusions: The results indicate slightly reduced light sensitivity and reduced colour discrimination among the exposed subjects compared to the controls. The findings may be due to previous exposure to acrylamide containing grouts among the tunnel workers.

Depressive disorders are associated with various cognitive impairments. Studies on whether or not these impairments persist into the euthymic phase have shown conflicting results, due to differences in test versions and in study samples. In this paper, we aimed to compare the cognitive performance of remitted depressed patients with that of age- and gender-matched healthy volunteers across a wide range of cognitive domains. In two studies, we found few differences on neutral as well as emotional information processing tests. The findings indicate that remitted depressed patients who use antidepressant medication still show an increased recognition of facial expression of fear compared to healthy controls. Patients also performed worse on a test of recognition of abstract visual information from long-term memory. No other residual cognitive impairments were found. These results indicate that most of the cognitive impairments associated with depression resolve with recovery through medication, even when recovery is incomplete. Considering the finding that remitted depressed patients have higher levels of cognitive reactivity, future studies may investigate the possibility that these cognitive impairments have not resolved but have become latent, and may therefore easily be triggered by small changes in mood state.

The authors assessed effects of alcohol consumption on different types of working memory (WM) tasks in an attempt to characterize the nature of alcohol effects on cognition. The WM tasks varied in 2 properties of materials to be retained in a 2-stimulus comparison procedure. Conditions included (a) spatial arrays of colors, (b) temporal sequences of colors, (c) spatial arrays of spoken digits, and (d) temporal sequences of spoken digits. Alcohol consumption impaired memory for auditory and visual sequences but not memory for simultaneous arrays of auditory or visual stimuli. These results suggest that processes needed to encode and maintain stimulus sequences, such as rehearsal, are more sensitive to alcohol intoxication than other WM mechanisms needed to maintain multiple concurrent items, such as focusing attention on them. These findings help to resolve disparate findings from prior research on alcohol's effect on WM and on divided attention. The results suggest that moderate doses of alcohol impair WM by affecting certain mnemonic strategies and executive processes rather than by shrinking the basic holding capacity of WM., ((c) 2008 APA, all rights reserved.)

The distractibility that schizophrenia patients display may be the result of a deficiency in filtering out irrelevant information. The aim of the current study was to assess whether patients with schizophrenia exhibit greater difficulty when task-irrelevant features change compared to healthy participants. Thirteen medicated outpatients with a diagnosis of schizophrenia and thirteen age- and parental education-matched controls performed a target selection task in which the task-relevant letter or the task-irrelevant features of color, and/or location repeated or switched. Participants were required to respond by pressing the appropriate key associated with the target letter. These patients with schizophrenia were slower when the task-relevant target letter switched than when it repeated. In contrast, schizophrenia patients performed similarly to controls when task-irrelevant information changed. Thus, we found no evidence that patients with schizophrenia were impaired in inhibiting irrelevant perceptual features. In contrast, changes in task-relevant features were problematic for patients relative to control participants. These results suggest that medicated outpatients who are mild to moderately symptomatic do not exhibit global impairments of feature processing. Instead, impairments are restricted to situations when task-relevant features vary. The current findings also suggest that when a course of action is not implied by an irrelevant feature, outpatients' behavior is not modulated by extraneous visual information any more than in healthy controls.

Although the effects of dopamine agonists on temporal discrimination have been widely studied, conclusions as to their behavioral and neurophysiological effects are difficult due to a number of discrepant findings in the literature. This study examined whether a previously unexplored procedural difference could account for some of these discrepancies. In three experiments, pigeons categorized the duration of temporal samples during two variants of the interval-bisection procedure. In the position variant, responses to a side key that corresponded to the sample duration produced food. In the color-matching variant, responses to the key color that corresponded to the sample duration produced food. Across experiments, d-amphetamine produced a general disruption of temporal discrimination not accompanied by over or underestimation of time in both procedures. This effect occurred whether pigeons were exposed to both procedures within session (Experiment 1) or across conditions (Experiments 2 and 3) and whether the pigeons were drug experienced (Experiments 1 and 2) or naïve (Experiment 3). Analyses of the cumulative normal functions fitted to the proportion-long response data indicated that d-amphetamine produced its effects by selectively decreasing stimulus control, rather than by affecting timing.

Purpose: To study prospectively retinal function, color discrimination, and ocular toxicity in women treated with standard-dosage tamoxifen for breast cancer., Methods: Thirty visually asymptomatic patients with at least 2 years of continuous tamoxifen therapy underwent multifocal electroretinography (ERG), color discrimination testing, and ophthalmic examination. The results were compared with 17 patients who were not taking tamoxifen after breast cancer surgery and to an additional age-matched group of 21 healthy women., Results: Multifocal electroretinogram amplitudes and latencies were comparable among the three studied groups, and individual recordings were within age norms from our own lab. In the treated group, mild diffuse color vision loss was found in two patients with normal fundi. Three other patients had ocular toxic effects, with two cases of refractile retinal crystals and one case of keratopathy., Conclusions: The aspects of central retinal function that are assessed by multifocal ERG were not affected even after at least 2 years of tamoxifen use, suggesting that the multifocal ERG is not sufficiently sensitive to detect tamoxifen-associated change that might occur. Some degree of color vision loss and ocular toxic effects were found in a few cases of this cohort suggesting that women using tamoxifen should receive an eye exam at least as often as recommended for middle-aged people.

Aims: To investigate whether adolescent heavy drinkers exhibit biased cognitive processing of alcohol-related cues and impulsive decision making., Design: A between-subjects design was employed., Setting: Classrooms in a single sixth-form college in Merseyside, UK., Participants: Ninety adolescent students (mean age 16.83 years), of whom 38% were identified as heavy drinkers and 36% were identified as light drinkers, based on a tertile split of their weekly alcohol consumption., Measurements: Participants provided information about alcohol consumption before completing measures of alcohol craving, delay discounting and an "alcohol Stroop" in which they were required to name the colour in which alcohol-related and matched control words were printed., Findings: Compared to light drinkers, heavy drinkers showed more pronounced discounting of delayed hypothetical monetary and alcohol rewards, which is indicative of a more short-term focus in decision making in heavy drinkers. Heavy drinkers were also slower to colour-name alcohol-related words, which indicates an attentional bias for alcohol-related cues. In all participants, measures of delay discounting and attentional bias were correlated moderately with each other, and also with the level of alcohol consumption and with alcohol craving., Conclusions: In adolescents, heavy alcohol use is associated with biased attentional processing of alcohol-related cues and a shorter-term focus in decision making.