Abstract:
:Using suction electrodes, photocurrent responses to 100-ms saturating flashes were recorded from isolated retinal rods of the larval-stage tiger salamander (Ambystoma tigrinum). The delay period (Tc) that preceded recovery of the dark current by a criterion amount (3 pA) was analyzed in relation to the flash intensity (If), and to the corresponding fractional bleach (R*0/Rtot) of the visual pigment; R*0/Rtot was compared with R*s/Rtot, the fractional bleach at which the peak level of activated transducin approaches saturation. Over an approximately 8 ln unit range of I(f) that included the predicted value of R*s/Rtot, Tc increased linearly with ln I(f). Within the linear range, the slope of the function yielded an apparent exponential time constant (tau c) of 1.7 +/- 0.2 s (mean +/- S.D.). Background light reduced the value of Tc measured at a given flash intensity but preserved a range over which Tc increased linearly with ln I(f); the linear-range slope was similar to that measured in the absence of background light. The intensity dependence of Tc resembles that of a delay (Td) seen in light-scattering experiments on bovine retinas, which describes the period of essentially complete activation of transducin following a bright flash; the slope of the function relating Td and ln flash intensity is thought to reflect the lifetime of photoactivated visual pigment (R*) (Pepperberg et al., 1988; Kahlert et al., 1990). The present data suggest that the electrophysiological delay has a similar basis in the deactivation kinetics of R*, and that tau c represents TR*, the lifetime of R* in the phototransduction process. The results furthermore suggest a preservation of the "dark-adapted" value of TR* within the investigated range of background intensity.
journal_name
Vis Neuroscijournal_title
Visual neuroscienceauthors
Pepperberg DR,Cornwall MC,Kahlert M,Hofmann KP,Jin J,Jones GJ,Ripps Hdoi
10.1017/s0952523800006441subject
Has Abstractpub_date
1992-01-01 00:00:00pages
9-18issue
1eissn
0952-5238issn
1469-8714pii
S0952523800006441journal_volume
8pub_type
杂志文章abstract::Thresholds for detection of light by a dark-adapted test eye were measured while the other, non-test eye was either similarly dark adapted or while it was exposed to an intense red adapting field. An interocular effect that depends on the retinal location of the test was found: compared to the threshold during binocul...
journal_title:Visual neuroscience
pub_type: 杂志文章
doi:10.1017/s0952523800005095
更新日期:1992-04-01 00:00:00
abstract::Eyes of stomatopod crustaceans, or mantis shrimps, contain the greatest diversity of visual pigments yet described in any species, with as many as ten or more spectral classes present in a single retina. In this study, the eyes of seven species of mantis shrimp from three superfamilies of stomatopods were examined for...
journal_title:Visual neuroscience
pub_type: 杂志文章
doi:10.1017/s095252380000612x
更新日期:1993-09-01 00:00:00
abstract::Several studies document rudimentary color vision under dim illumination. Here, hue perceptions of paper color samples were determined for a wide range of light levels, including very low light levels where rods alone mediate vision. The appearances of 24 paper color samples from the OSA Uniform Color Scales were gaug...
journal_title:Visual neuroscience
pub_type: 杂志文章
doi:10.1017/S0952523806233492
更新日期:2006-05-01 00:00:00
abstract::We have investigated the effects of inactivation of localized sites in area 17 on the visual responses of cells in visuotopically corresponding regions of area 18. Experiments were performed on adult normal cats. The striate cortex was inactivated by the injection of nanoliters of lidocaine hydrochloride or of gamma-a...
journal_title:Visual neuroscience
pub_type: 杂志文章
doi:10.1017/s0952523800001826
更新日期:1992-12-01 00:00:00
abstract::To investigate the influence of voltage-sensitive conductances in shaping light-evoked responses of retinal bipolar cells, whole-cell recordings were made in the slice preparation of the tiger salamander, Ambystoma tigrinum. To study contrast encoding, the retina was stimulated with 0.5-s steps of negative and positiv...
journal_title:Visual neuroscience
pub_type: 杂志文章
doi:10.1017/s0952523803201036
更新日期:2003-01-01 00:00:00
abstract::The human visual system is remarkably tolerant to degradation in image resolution: human performance in scene categorization remains high no matter whether low-resolution images or multimegapixel images are used. This observation raises the question of how many pixels are required to form a meaningful representation o...
journal_title:Visual neuroscience
pub_type: 杂志文章
doi:10.1017/S0952523808080930
更新日期:2009-01-01 00:00:00
abstract::AMPA-selective glutamate receptors play a major role in glutamatergic neurotransmission in the retina and are expressed in a variety of neuronal subpopulations. In the present study, immunocytochemical techniques were used to visualize the distribution of GluR2 and GluR4 subunits in the cat retina. Results were compar...
journal_title:Visual neuroscience
pub_type: 杂志文章
doi:10.1017/s0952523899166100
更新日期:1999-11-01 00:00:00
abstract::One type of retinal ganglion cells prefers object motion in a particular direction. Neuronal mechanisms for the computation of motion direction are still unknown. We quantitatively mapped excitatory and inhibitory regions of receptive fields for directionally selective retinal ganglion cells in the Japanese quail, and...
journal_title:Visual neuroscience
pub_type: 杂志文章
doi:10.1017/s0952523800172086
更新日期:2000-03-01 00:00:00
abstract::The hypothesis that dichromatic behavior on a clinical anomaloscope can be explained by the complement and arrangement of the long- (L) and middle-wavelength (M) pigment genes was tested. It was predicted that dichromacy is associated with an X-chromosome pigment gene array capable of producing only a single functiona...
journal_title:Visual neuroscience
pub_type: 杂志文章
doi:10.1017/s0952523804213293
更新日期:2004-05-01 00:00:00
abstract::We have studied the steady-state PERG in human subjects in response to red-green plaid patterns modulated either in luminance or in chromaticity or both. By varying the relative luminance of the red and green components, a value could be obtained at which the PERG amplitude was either minimum or locally maximum. This ...
journal_title:Visual neuroscience
pub_type: 杂志文章
doi:10.1017/s0952523800003825
更新日期:1994-09-01 00:00:00
abstract::Ganglion cells of the cat retina that are neither alpha nor beta cells are often lumped for convenience into a single anatomical group--the gamma cells (Boycott & Wässle, 1974; Stone, 1983; Wässle & Boycott, 1991). Defined in this way, gamma cells are the morphological counterpart to the physiological W-cell class, wh...
journal_title:Visual neuroscience
pub_type: 杂志文章
doi:10.1017/s095252380000897x
更新日期:1995-07-01 00:00:00
abstract::The peripheral visual field is marked by a deterioration in color sensitivity, sometimes attributed to the random wiring of midget bipolar cells to cone photoreceptors in the peripheral retina (Mullen, 1991; Mullen & Kingdom, 1996). Using psychophysical methods, we explored differences in the sensitivity of peripheral...
journal_title:Visual neuroscience
pub_type: 杂志文章
doi:10.1017/s0952523803205058
更新日期:2003-09-01 00:00:00
abstract::The outer plexiform layer of the retina contains a neural circuit in which cone synaptic terminals are electrically coupled and release glutamate onto wide-field and narrow-field horizontal cells. These are also electrically coupled and feed back through a GABAergic synapse to cones. In cat this circuit's structure is...
journal_title:Visual neuroscience
pub_type: 杂志文章
doi:10.1017/s0952523800008440
更新日期:1995-05-01 00:00:00
abstract::A model of contrast discrimination performance in human observers is developed and then extended to cover effects on performance of anticholinergic drugs. It is shown that it is necessary to assume that neural noise increases at high spatial frequencies in order to provide a satisfactory model of variations in discrim...
journal_title:Visual neuroscience
pub_type: 杂志文章
doi:10.1017/s0952523800009123
更新日期:1996-09-01 00:00:00
abstract::Anterograde transport of cholera toxin subunit B (CTb) was used to study the retinal projections in birds, with an emphasis on retinohypothalamic connections. Pigeons (Columbia livia) were deeply anesthetized and received unilateral intraocular injections of CTb. In addition to known contralateral retinorecipient regi...
journal_title:Visual neuroscience
pub_type: 杂志文章
doi:10.1017/s0952523800002376
更新日期:1994-05-01 00:00:00
abstract::Alpha ganglion cells from the midperiphery of the rabbit retina were recorded intracellularly under visual control, in a superfused everted eyecup, and labeled with HRP. Their physiology and large somata with broad dendritic arbors identified them as uniform populations of ON- and OFF-center alpha ganglion cells, whic...
journal_title:Visual neuroscience
pub_type: 杂志文章
doi:10.1017/s0952523800011512
更新日期:1997-03-01 00:00:00
abstract::We examine the assumptions that the fovea contains equal numbers of inner (invaginating or ON) and outer (flat or OFF) midget bipolar cells and equal numbers of inner and outer diffuse bipolar cells. Based on reconstruction from electron photomicrographs of serial thin sections through the fovea of a macaque monkey, w...
journal_title:Visual neuroscience
pub_type: 杂志文章
doi:10.1017/s0952523803202091
更新日期:2003-03-01 00:00:00
abstract::Retinal ganglion cell (RGC) dendritic atrophy is an early feature of many forms of retinal degeneration, providing a challenge to RGC classification. The characterization of these changes is complicated by the possibility that selective labeling of any particular class can confound the estimation of dendritic remodeli...
journal_title:Visual neuroscience
pub_type: 杂志文章
doi:10.1017/S0952523814000248
更新日期:2014-11-01 00:00:00
abstract::Amacrine cells are a morphologically and functionally diverse group of inhibitory interneurons. Morphologically, they have been divided into approximately 30 types. Although this diversity is probably important to the fine structure and function of the retinal circuit, the amacrine cells have been more generally divid...
journal_title:Visual neuroscience
pub_type: 杂志文章,评审
doi:10.1017/S0952523812000028
更新日期:2012-01-01 00:00:00
abstract::Simple reaction times (RTs) were measured to brief temporally blurred (total onset 570 ms) Gaussian isoluminant chromatic patches (s.d. 0.5 degrees) whose chromaticities lay along the cardinal chromatic axes (0 degrees, 90 degrees, 180 degrees, and 270 degrees in MBDKL color space). Bipolar adapting stimuli were emplo...
journal_title:Visual neuroscience
pub_type: 杂志文章
doi:10.1017/S0952523808080449
更新日期:2008-05-01 00:00:00
abstract::The visual information that first-order cortical cells receive is contained in the visually evoked spike trains of geniculate relay cells. To address functional issues such as the ON/OFF structure of visual cortical receptive fields with modelling studies, a geniculate cell model is needed where the spatial and tempor...
journal_title:Visual neuroscience
pub_type: 杂志文章
doi:10.1017/s0952523898156158
更新日期:1998-11-01 00:00:00
abstract::Although excitotoxins derived from acidic amino acids are known to damage neurons in the inner nuclear and ganglion cell layers of the retina, little is known about their effects on photoreceptors. This study examines the acute and long-term effects of excitotoxins on photoreceptors of the chick retina. The zinc-iodid...
journal_title:Visual neuroscience
pub_type: 杂志文章
doi:10.1017/s0952523800001152
更新日期:1989-01-01 00:00:00
abstract::In the reverse Stroop task, observers are instructed to ignore the ink color in which a color word is printed (the distractor color) and to respond to the meaning of the color word (the target). Reaction times (RTs) are faster with congruent combinations when the ink color matches the word than with incongruent combin...
journal_title:Visual neuroscience
pub_type: 杂志文章
doi:10.1017/S0952523806233388
更新日期:2006-05-01 00:00:00
abstract::Following up on a prior study of contour and brightness processing in visual masking (Breitmeyer et al., 2006), we investigated the effects of a binocular and dichoptic para-contrast masking on the visibility of the contour and brightness of a target presented to the other eye. Combined, the results support the contri...
journal_title:Visual neuroscience
pub_type: 杂志文章
doi:10.1017/S0952523807070393
更新日期:2007-03-01 00:00:00
abstract::Some visual stimuli produce a strong percept of motion, even though they fail to excite motion detectors based on Fourier energy or cross correlation. Models which suffice to explain the motion percept in these non-Fourier motion (NFM) stimuli include linear spatiotemporal filtering, followed by rectification, followe...
journal_title:Visual neuroscience
pub_type: 杂志文章
doi:10.1017/s0952523800009573
更新日期:1992-08-01 00:00:00
abstract::We recorded the responses of neurons from the cat's lateral geniculate nucleus to drifting sine-wave grating stimuli both before and during electrical stimulation of the parabrachial region of the midbrain. The parabrachial region provides a mostly cholinergic input to the lateral geniculate nucleus, and our goal was ...
journal_title:Visual neuroscience
pub_type: 杂志文章
doi:10.1017/s0952523800005332
更新日期:1993-07-01 00:00:00
abstract::In the human eye, domination of the electroretinogram (ERG) by the b-wave and other postreceptor components ordinarily obscures all but the first few milliseconds of the rod photoreceptor response to a stimulating flash. However, recovery of the rod response after a bright rest flash can be analyzed using a paired-fla...
journal_title:Visual neuroscience
pub_type: 杂志文章
doi:10.1017/s0952523800008774
更新日期:1997-01-01 00:00:00
abstract::We studied the functional connectivity of cells in the lateral geniculate nucleus (LGN) with the primary visual cortex (V1) in anesthetized marmosets (Callithrix jacchus). The LGN sends signals to V1 along parallel visual pathways called parvocellular (P), magnocellular (M), and koniocellular (K). To better understand...
journal_title:Visual neuroscience
pub_type: 杂志文章
doi:10.1017/S0952523814000066
更新日期:2014-05-01 00:00:00
abstract::To explore the possible influence of defined genetic backgrounds on photoreceptor viability and function in mice carrying a targeted disruption of the rhodopsin gene, the severities of retinopathies in Rho-/- mice on C57BL/6J and 129Sv congenic backgrounds were compared by light microscopy and electroretinography and ...
journal_title:Visual neuroscience
pub_type: 杂志文章
doi:10.1017/s0952523801183100
更新日期:2001-05-01 00:00:00
abstract::Anatomical and electrophysiological studies have provided us with detailed information regarding the extent and topography of the primary (V1) and secondary (V2) visual areas in primates. The consensus about the V1 and V2 maps, however, is in sharp contrast with controversies regarding the organization of the cortical...
journal_title:Visual neuroscience
pub_type: 杂志文章,评审
doi:10.1017/S0952523815000188
更新日期:2015-01-01 00:00:00