The resonant frequencies of rod and cone electroretinograms
نویسندگان
چکیده
The ERG of the albino rat and the gray squirrel was studied with sinusoidally flickering light and D.C. amplification. It was found that: The rat's ERG has a resonant frequency of 2 to 4 c.p.s. with attenuation at both lower and higher frequencies; the bandwidth of the response extends from 0.05 to 25 c.p.s. The squirrel's ERG has a resonant frequency of 9 to 10 c.p.s. xoiih a bandwidth of approximately 1 to 100 c.p.s. Increasing the light intensity broadens the bandwidth but does not shift the resonant frequency greatly. Analogies are made between the response of these pure rod and cone retinas and the low-frequency characteristics of human vision.
منابع مشابه
Properties of Flicker ERGs in Rat Models with Retinal Degeneration
Purpose. To describe the characteristics of rod and cone functions in rat models for congenital stationary night blindness (CSNB) and retinal cone dysfunction (RCD). Methods. Rod and cone function were isolated by recording the rod-/cone-driven flicker and blue light flicker electroretinograms (ERGs). Results. During dark adaptation, the amplitudes of flicker ERGs in CSNB rats were lower than t...
متن کاملThe Spatial Properties of L- and M-Cone Inputs to Electroretinograms That Reflect Different Types of Post-Receptoral Processing
We studied the spatial arrangement of L- and M-cone driven electroretinograms (ERGs) reflecting the activity of magno- and parvocellular pathways. L- and M-cone isolating sine wave stimuli were created with a four primary LED stimulator using triple silent substitution paradigms. Temporal frequencies were 8 and 12 Hz, to reflect cone opponent activity, and 30, 36 and 48 Hz to reflect luminance ...
متن کاملRod- and cone-isolated flicker electroretinograms and their response summation characteristics.
This study defined the amplitude and phase characteristics of rod- and cone-isolated flicker electroretinograms (ERGs) and determined how these responses summate to generate the nonreceptor-specific ERG. Full-field ERGs were obtained from six normally sighted subjects (age 26 to 44 years) using a four-primary LED-based photostimulator and standard recording techniques. The four primaries were e...
متن کاملElectroretinograms in English setters with neuronal ceroid lipofuscinosis.
Full-field electroretinograms (ERGs) were recorded from three adult English setters with advanced neuronal ceroid lipofuscinosis and three normal controls. Affected setters showed 30% to 40% reductions in a-wave and b-wave amplitudes, normal cone and rod b-wave implicit times, and slightly elevated a-wave and b-wave thresholds. The ERGs of these affected setters differed from those that have be...
متن کاملHistopathologic and immunohistochemical study of an autopsy eye with X-linked cone degeneration.
We performed a histopathologic and immunohistochemical study of eyes obtained at autopsy of an 84-year-old man from a family with X-linked cone degeneration in which affected members have a 6.5-kilobase deletion in the red cone pigment gene. At his most recent ocular examination, at age 71 years, this patient had had a visual acuity of 20/200 OU, fundus changes suggestive of macular degeneratio...
متن کامل