Richard M. Held - US grants

Investigations with cats and monkeys have shown that binocular anomalies present during a susceptible period of development may result in loss of binocularity, including stereopsis, and the development of amblyopia. Clinical observations indicate a similar susceptibiltiy in humans. The extent to which the visual system can recover from these deficits depends, in part, on the time and adequacy of correction during the susceptible period. The implication of this work is theoretically straightforward. If the patient can be treated at the proper time during the critical period of development, his prognosis for the development of normal visual functioning may be made more favorable. Although susceptible periods for development of the human system are recognized, their courses are nor clearly delineated. The major objective of the proposed research will be to ascertain the timing, and variations in the sensitivity, of periods of susceptibility of the human visual system to modification by occlusion and misaligned visual axes. We shall try to define the relationship between the loss of binocularity and the development of amblyopia. The main method will entail taking sequential measures of resolution, both grating and stereoacuity, before, during, and after therapeutic intervention. In addition, measures will be made of the development of the relative gain between nasotemporal and temporonasal motion-induced optokinetic nystagmus. The outcome should be relevant to determining the optimal time for surgical intervention and for strabismic therapy. The proposed research is a natural extension of ongoing work in our laboratory which deals with the development of vision in normal and astigmatic infants.

Twelve investigators request renewal of core support for Vision Research. Core support has strengthened on-going research in the laboratories of these investigators working in vision research and has enhanced collaboration among core investigators and with eye care professionals. The research deals primarily with central visual processes and utilizes the techniques of neuroanatomy, neurophysiology, psychophysics and behavior study. Support is requested for common facilities and services, to enhance internal collaboration with the group, and to increase the exchange of information and skills with eye care professionals. The fields represented include: (a) Neuroanatomy of the visual pathways explored by both classic and modern techniques; (b) Normal and abnormal development of the visual nervous system as assessed by anatomical, physiological, and behavioral procedures; (c) Extra-cellular recording in the nuclei of the visual nervous system in both anaesthetized and behaving animals; (d) Analysis of visual, vestibular, and motor interfacing by physiological and behavioral techniques; (e) Development of vision and visuomotor coordination in human neonates assessed by psychophysical methods; (f) Development of vision and visuomotor coordination under aberrant conditions of seeing including astigmatism, early occlusion, strabismus, and anisometropia; (g) Psychophysics of selective blindnesses and of pattern perception; (h) Alternations of visual function in patients with brain damage; (i) Computational approaches to information processing by the visual nervous system. Collaboration with eye care professionals already occurs. It may be greatly strengthened by the measures proposed.

The objective of this proposal is to continue a program of research designed to determine the course of development of visuospatial functions in human infants and children. The results will be relevant to our understanding of maturational and exposure-induced changes in the underlying neuronal mechanisms, to the recognition of early, potentially pathological, deviations from normal developments, and to possible ameliorative treatment. The following six specific directions of research are proposed. 1. Development of Orientational Selectivity: To determine the course of the sharpening of orientational tuning to edges through infancy and childhood. 2. Development of Spatial Frequency Selectivity: To determine the course of progressively narrowing tuning during infancy and childhood. 3. Development of Binocular Vision and Oculomotor Control: To establish the relationship between the development of stereopsis, the directional symmetrization of monocular OKN, and eye alignments to visual targets. 4. Analysis of Early-Onset Myopia and Visual Function in Children with Known Refractive Histories: To determine the influence of infantile refractive error on later error and on visual and oculomotor function. 5. Analysis of Sex Differences in Visual Development: To determine the magnitude and time course of sex differences and their hormonal cause. 6. Computerized Data Base and Control of Testing Procedures: To continue cumulating data under computer control and developing automated test procedures for use in laboratory and clinic.

The objective of this proposal is to continue a program of research designed to determine the course of development of visuospatial functions in human infants and children. The results will be relevant to our understanding of maturational and exposure-induced changes in the underlying neuronal mechanisms, to the recognition of early, potentially pathological, deviations from normal developments, and to possible ameliorative treatment. The following six specific directions of research are proposed. 1. Development of Orientational Selectivity: To determine the course of the sharpening of orientational tuning to edges through infancy and childhood. 2. Development of Spatial Frequency Selectivity: To determine the course of progressively narrowing tuning during infancy and childhood. 3. Development of Binocular Vision and Oculomotor Control: To establish the relationship between the development of stereopsis, the directional symmetrization of monocular OKN, and eye alignments to visual targets. 4. Analysis of Early-Onset Myopia and Visual Function in Children with Known Refractive Histories: To determine the influence of infantile refractive error on later error and on visual and oculomotor function. 5. Analysis of Sex Differences in Visual Development: To determine the magnitude and time course of sex differences and their hormonal cause. 6. Computerized Data Base and Control of Testing Procedures: To continue cumulating data under computer control and developing automated test procedures for use in laboratory and clinic.