OPTICAL STIMULATOR, MICROELECTRODE ADVANCER, AND ASSOCIATED EQUIPMENT FOR INTRARETINAL NEUROPHYSIOLOGY IN CLOSED MAMMALIAN EYES.

An optical stimulator is described to meet the special requirements of retinal neurophysiology. It is compact and convenient to use, and modular construction confers flexibility of problems to which it may be applied. The maximum stimulus intensity from a Zeiss tungsten light source gives 4.19 log m–c of illuminance at the cat retina. An electromagnetic shutter provides light pulses which rise or fall to within 1/e of the final value in 0.3–0.4 msec. Controls are included for stimulus intensity, color, duration, and frequency. Both spot and annular stimuli of variable size are provided. The stimulus may be positioned anywhere on the retina by a combination of coarse and micrometer controls. Interchangeable stimulus light sources are used for special problems, and a simple attachment permits studying the Stiles-Crawford effect. A background beam is also provided with controls for intensity and color. A direct ophthalmoscopic view of the fundus gives high resolution of retinal details.A modified eye holder provides three needle channels into the fundus of the eye. An improved hydraulic advancer controls microelectrode depth in the retina. A simple head holder is used to position the cat or monkey eye in the stimulator.

[1]  K. Brown,et al.  Rod Receptor Potential from the Retina of the Night Monkey , 1962, Nature.

[2]  K. Brown,et al.  Isolation and Identification of a Receptor Potential from the Pure Cone Fovea of the Monkey Retina , 1962, Nature.

[3]  T. Wiesel,et al.  Analysis of the intraretinal electroretinogram in the intact cat eye , 1961, The Journal of physiology.

[4]  T N WIESEL,et al.  Intraretinal recording with micropipette electrodes in the intact cat eye , 1959, The Journal of physiology.

[5]  I H WAGMAN,et al.  Neural limitations of visual excitability. I. The time course of monocular light adaptation. , 1959, Journal of the Optical Society of America.

[6]  M. Pirenne,et al.  The absolute visual threshold recorded from the lateral geniculate body of the cat , 1959, The Journal of physiology.

[7]  H. Barlow,et al.  Change of organization in the receptive fields of the cat's retina during dark adaptation , 1957, The Journal of physiology.

[8]  H. Barlow,et al.  MAINTAINED ACTIVITY IN THE CAT'S RETINA IN LIGHT AND DARKNESS , 1957, The Journal of general physiology.

[9]  D. Hubel.  Tungsten Microelectrode for Recording from Single Units. , 1957, Science.

[10]  S. A. Talbot,et al.  A multibeam ophthalmoscope for the study of retinal physiology. , 1952, Journal of the Optical Society of America.

[11]  P. R. McDonald,et al.  Light and dark adaptation of single photoreceptor elements in the eye of Limulus. , 1947, Journal of cellular and comparative physiology.

[12]  S. W. Kuffler.  Discharge patterns and functional organization of mammalian retina. , 1953, Journal of neurophysiology.

[13]  S. W. Kuffler.  Neurons in the retina; organization, inhibition and excitation problems. , 1952, Cold Spring Harbor symposia on quantitative biology.