We report three unrelated patients with mutations in the GRM6 gene that normally encodes the glutamate receptor mGluR6. This neurotransmitter receptor has been shown previously to be present only in the synapses of the ON bipolar cell dendrites, and it mediates synaptic transmission from rod and cone photoreceptors to this type of second-order neuron. Despite the synaptic defect, best visual acuities were normal or only moderately reduced (20͞15 to 20͞40). The patients were night blind from an early age, and when maximally dark-adapted, they could perceive lights only with an intensity equal to or slightly dimmer than that normally detected by the cone system (i.e., 2-3 log units above normal). Electroretinograms (ERGs) in response to single brief flashes of light had clearly detectable a-waves, which are derived from photoreceptors, and greatly reduced b-waves, which are derived from the second-order inner retinal neurons. ERGs in response to sawtooth flickering light indicated a markedly reduced ON response and a nearly normal OFF response. There was no subjective delay in the perception of suddenly appearing white vs. black objects on a gray background. These patients exemplify a previously unrecognized, autosomal recessive form of congenital night blindness associated with a negative ERG waveform. bipolar cell ͉ glutamate receptor ͉ retina

Purpose: To investigate the relationship between large-letter contrast sensitivity, high-contrast visual acuity, and visual field defects in patients with glaucoma. Methods:Patients with a diagnosis of glaucoma, glaucoma suspect, or ocular hypertension whose visual acuity was 20/40 (logMAR = 0.3) or better were included in the study. Visual acuity was measured using the Lighthouse visual acuity charts. Contrast sensitivity was measured using the Pelli-Robson (PR) chart. The mean depression (MD) score from the most recent Humphrey visual field was used to quantify the visual field defect.Results: A total of 120 eyes were studied. The PR contrast sensitivity score correlated more strongly with the MD of the visual field (r = .589, P < .001) than did the logMAR visual acuity (r =.193, P=.035). When just the eyes with openangle glaucoma were considered (N=54), the correlation was even greater for the PR score (r =.638). In ocular hypertensive eyes (N=25), the correlations to PR and logMAR were not that different (r =.394 for PR, r =.303 for logMAR). Pseudophakic eyes did not show as strong a correlation (r =.335) as did phakic eyes (r =.591). Conclusion:For glaucomatous eyes with visual acuity of 20/40 or better, a decrease in the contrast sensitivity correlates with increased visual field loss. We speculate that this decrease in contrast sensitivity in glaucoma patients may account for their complaints of poor vision despite normal or near normal visual acuity. 2001;99:213-218 Tr Am Ophth Soc

This paper reports the results of a recent questionnaire completed by 377 Australian primary and secondary physical education (PE) teachers who had used the sport education curriculum model. As such, it constitutes one of the few large-scale accounts of teachers' perceptions of a curriculum model first proposed by Siedentop in the early 1980s. The purpose of the questionnaire was to discover how teachers implemented the model and to report whether they believed it produced better learning outcomes, was responsive to particular types of students and their needs and helped students accept responsibility for their own PE. The report provides support for the view that sport education can be an exemplary context for pursuing a broader range of learning outcomes than PE has traditionally sought and achieved, and that many teachers' disappointment with the nature and quality of interactions with students can be overcome, in turn enhancing their 'quality of working life'.

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