Abstract：
:In this work we report on a unique and ancient type of eye, in which the lower surface of the upper calcite lens units possessed an enigmatic central bulge making the dioptric apparatus similar to a bifocal lens. This eye belonged to the trilobite Dalmanitina socialis, which became extinct several hundred million years ago. As far as we know, image formation by bifocal lenses of this kind did/does not occur in any other ancient or modern animal visual system. We suggest that the function of these bifocal lenses may be to enable the trilobite to see simultaneously both very near (e.g. floating food particles and tiny preys) and far (e.g. sea floor, conspecifics, or approaching enemies) in the optical environment through the central and peripheral lens region, respectively. This was the only reasonable function we could find to explain the puzzling lens shape. We admit that it is not clear whether bifocality was necessary for the animal studied. We show that the misleading and accidental resemblance of an erroneous correcting lens surface (designed by René DesCartes in 1637 [DesCartes, R. (1637). Oeuvres de DesCartes. La Géometrie. Livre 2. pp. 134. J. Maire, Leyden] to the correcting interface in the compound Dalmanitina lens may be the reason why the earlier students of the Dalmanitina lens did not recognize its possible bifocality.
journal_name
Vision Resjournal_title
Vision researchauthors
Gál J,Horváth G,Clarkson EN,Haiman Odoi
10.1016/s0042-6989(99)00216-3subject
Has Abstractpub_date
2000-01-01 00:00:00pages
843-53issue
7eissn
0042-6989issn
1878-5646pii
S0042-6989(99)00216-3journal_volume
40pub_type
杂志文章相关文献
VISION RESEARCH文献大全abstract：:The effect of competing non-target stimuli (distractors) presented together with a target for saccades was investigated with special emphasis on saccadic reaction time. Using the gap task (fixation point offset preceding target onset by 200 msec) high numbers of express saccades were obtained from four human subjects....
journal_title：Vision research
pub_type： 杂志文章
doi：10.1016/0042-6989(94)90312-3
更新日期：1994-07-01 00:00:00
abstract：:The effects of the involuntary ocular oscillations on visual resolution was examined in 22 albinos and 11 idiopaths with congenital nystagmus. The idiopaths showed a linear relationship between the proportion of the slow phase spent at low velocities (less than or equal to deg/sec) and the log of the minimum angle of ...
journal_title：Vision research
pub_type： 杂志文章
doi：10.1016/0042-6989(91)90063-b
更新日期：1991-01-01 00:00:00
abstract：:Previous studies have shown that attention to a particular stimulus feature, such as direction of motion or color, enhances neuronal responses to unattended stimuli sharing that feature. We studied this effect psychophysically by measuring the strength of the motion aftereffect (MAE) induced by an unattended stimulus ...
journal_title：Vision research
pub_type： 杂志文章
doi：10.1016/j.visres.2006.03.003
更新日期：2006-09-01 00:00:00
abstract：:The visual span for reading refers to the range of letters, formatted as in text, that can be recognized reliably without moving the eyes. It is likely that the size of the visual span is determined primarily by characteristics of early visual processing. It has been hypothesized that the size of the visual span impos...
journal_title：Vision research
pub_type： 杂志文章
doi：10.1016/j.visres.2007.08.002
更新日期：2007-10-01 00:00:00
abstract：:We applied new methods for canine eye-movement recording to the study of achiasmatic mutant Belgian Sheepdogs, documenting their nystagmus waveforms and comparing them to humans with either congenital nystagmus (CN) alone or in conjunction with achiasma. A sling apparatus with head restraints and infrared reflection w...
journal_title：Vision research
pub_type： 杂志文章
doi：10.1016/s0042-6989(97)00337-4
更新日期：1998-06-01 00:00:00
abstract：:We examined the ability of observers to determine the vertical alignment of three Gabor patches (cosine gratings tapered in X and Y by Gaussians) when the grating within the middle patch was moving right or left. The comparison patches were flickered in counterphase, as was the test patch in a control condition. In al...
journal_title：Vision research
pub_type： 杂志文章
doi：10.1016/0042-6989(91)90138-u
更新日期：1991-01-01 00:00:00
abstract：:Microspectrophotometry (MSP) shows rhodopsin highly concentrated (about 3.0 mmol/l) in rod outer segments (ROS). Calculation of the in vivo absorption spectrum of human rhodopsin from such data reveals a striking failure to agree with the action spectrum of human rod vision. Agreement is good between the spectral dist...
journal_title：Vision research
pub_type： 杂志文章
doi：10.1016/0042-6989(87)90155-6
更新日期：1987-01-01 00:00:00
abstract：:Illusory contours (ICs) are thought to be a result of processes involved in the perceptual recovery of occluded surfaces. Here, we investigate the relationship between real and illusory contour perception using a shape discrimination task and backward masking paradigm. ICs can mask other ICs when times between mask on...
journal_title：Vision research
pub_type： 杂志文章
doi：10.1016/j.visres.2004.07.034
更新日期：2005-01-01 00:00:00
abstract：:Using displacing prisms to dissociate the influence of optic flow and egocentric direction, previous research (Current Biology 8 (1998) 1191) showed that people primarily use egocentric direction to control their locomotion on foot, rather than optic flow. When wearing displacing prisms, participants followed the curv...
journal_title：Vision research
pub_type： 杂志文章
doi：10.1016/s0042-6989(02)00066-4
更新日期：2002-06-01 00:00:00
abstract：:When a visual stimulus is displaced during a saccade the displacement is often not noticed unless it is large compared to the amplitude of the eye movement. Displacement detection is improved, however, if a blank intervenes between saccade target offset and the presentation of the displaced post-saccadic stimulus. Thi...
journal_title：Vision research
pub_type： 杂志文章
doi：10.1016/j.visres.2017.09.004
更新日期：2018-01-01 00:00:00
abstract：:It is possible to discriminate between grating contrasts over a 300-fold contrast range, whereas V1 neurons have very limited dynamic ranges. Using populations of model neurons with contrast-response parameters taken from electrophysiological studies (cat and macaque), we investigated ways of combining responses to co...
journal_title：Vision research
pub_type： 杂志文章
doi：10.1016/s0042-6989(03)00277-3
更新日期：2003-08-01 00:00:00
abstract：:The kinetics of synaptic transfer from photoreceptors to second order neurons have been determined in the retina of the snapping turtle. Analysis of the fluctuations resulting from the random release of cone transmitter molecules reveals that the action on postsynaptic channels of the depolarizing bipolar cells is pro...
journal_title：Vision research
pub_type： 杂志文章
doi：10.1016/0042-6989(83)90083-4
更新日期：1983-01-01 00:00:00
abstract：:We present a novel binocular stimulus without conventional disparity cues whose presence and depth are revealed by sequential monocular stimulation (delay > or = 80 ms). Vertical white lines were occluded as they passed behind an otherwise camouflaged black rectangular target. The location (and instant) of the occlusi...
journal_title：Vision research
pub_type： 杂志文章
doi：10.1016/j.visres.2005.06.015
更新日期：2006-03-01 00:00:00
abstract：:Central vision is substantially over represented in the lateral geniculate nucleus (dLGN) and striate cortex. The over representation could be accompanied by a selective expansion of central vision in parvocellular dLGN, in which case the ratio of parvocellular to magnocellular inputs to striate cortex should change w...
journal_title：Vision research
pub_type： 杂志文章
doi：10.1016/s0042-6989(98)00319-8
更新日期：1999-06-01 00:00:00
abstract：:Perceptual constancy refers to the ability to stabilize the representation of an object even though the retinal image of the object undergoes variations. In previous studies, we proposed a General Object Constancy (GOC) hypothesis to demonstrate a common stabilization mechanism for perception of an object's features, ...
journal_title：Vision research
pub_type： 杂志文章
doi：10.1016/j.visres.2016.09.015
更新日期：2016-12-01 00:00:00
abstract：:Dynamic random dot fusion, stereopsis and stereoacuity were evaluated in 149 healthy, fullterm infants, using both forced-choice preferential looking (FPL) and steady-state visual evoked potential (VEP) protocols. Few infants aged 2-3 months demonstrated fusion or stereopsis in either the FPL or VEP protocol; most inf...
journal_title：Vision research
pub_type： 临床试验,杂志文章
doi：10.1016/0042-6989(95)00183-2
更新日期：1996-05-01 00:00:00
abstract：:By inducing feature-contingent depth aftereffects, we show that the human visual system combines feature information with depth information. These contingent aftereffects were revealed through the use of a novel selective adaptation paradigm whose stimuli required the combination of feature and depth information in or...
journal_title：Vision research
pub_type： 杂志文章
doi：10.1016/s0042-6989(01)00294-2
更新日期：2002-02-01 00:00:00
abstract：:The e-wave and a delayed-OFF increase in extracellular K+ concentration are both maximum in the distal half of the inner plexiform layer. These responses also have similar latency, time-course, intensity-dependence, surround properties, and sensitivity to tetrodotoxin. Current source-density analysis of the e-wave rev...
journal_title：Vision research
pub_type： 杂志文章
doi：10.1016/0042-6989(88)90136-8
更新日期：1988-01-01 00:00:00
abstract：:The cornea of the goby Pomatoschistus minutus is iridescent. Spectral reflectance measurements show that the colour of the iridescence responds to light shifting to longer wavelengths when illuminated and shifting to shorter wavelengths when dark adapted. After 2-3 hr dark adaptation the iridescence is no longer visib...
journal_title：Vision research
pub_type： 杂志文章
doi：10.1016/0042-6989(87)90193-3
更新日期：1987-01-01 00:00:00
abstract：:One of the ultimate goals of vision research is to understand how some elements are grouped together and differentiated from others to form object representations in a complex visual scene. There exists an extensive literature on this grouping/segmentation problem, but most of the studies have used un-recognizable sti...
journal_title：Vision research
pub_type： 杂志文章
doi：10.1016/j.visres.2009.08.002
更新日期：2009-10-01 00:00:00
abstract：:The changes with age in the accommodation responses to dynamic stimuli can reveal useful information on the factors underlying presbyopia development. Analysis of the monocular accommodation responses of 19 normal observers (ages 18-49 years) to stimuli whose vergence varied sinusoidally with time at different tempora...
journal_title：Vision research
pub_type： 杂志文章
doi：10.1016/j.visres.2004.07.016
更新日期：2004-12-01 00:00:00
abstract：:Thresholds for the detection of rotation and divergence in the presence of a translational component in sparse random dot patterns are determined for human observers and two computer algorithms. The algorithms only make use of local velocity directions and not of local velocity magnitude (speed). The results show that...
journal_title：Vision research
pub_type： 杂志文章
doi：10.1016/0042-6989(96)00070-3
更新日期：1996-11-01 00:00:00
abstract：:Dark-adapted rods suppress cone-mediated flicker detection. This study evaluates the effect that rod activity has on cone temporal processing by investigating whether rod mediated suppression changes the cone pathway impulse response function, regardless of the form of the temporal signal. Stimuli were generated with ...
journal_title：Vision research
pub_type： 杂志文章
doi：10.1016/j.visres.2008.04.003
更新日期：2008-11-01 00:00:00
abstract：:This study examined spatial-frequency effects on a motion-pooling process in which spatially distributed local one-dimensional motion signals are integrated into the perception of global two-dimensional motion. Motion pooling over two- to three-octave frequency differences was found to be nearly impossible when all Ga...
journal_title：Vision research
pub_type： 杂志文章
doi：10.1016/j.visres.2010.03.016
更新日期：2010-06-01 00:00:00
abstract：:With the use of the simple motor reaction time (RT), we examined the contribution of the hemiretinas to the timing of the pattern reversal visual evoked potential (PVEP). RTs were obtained to the reversal of a progressively dimmer check falling either on the central, nasal, temporal, superior or inferior retina. Resul...
journal_title：Vision research
pub_type： 杂志文章
doi：10.1016/s0042-6989(97)00117-x
更新日期：1997-11-01 00:00:00
abstract：:Morphological patterns of the retina, cone size and density, rod density, rod-cone ratio, ganglion cell density, convergence of receptor cells, resolving power (RP) and regionalization were examined throughout life history in roach and in adults of asp, bream, common carp, roach and sabre carp. The retina of hatchling...
journal_title：Vision research
pub_type： 杂志文章
doi：10.1016/0042-6989(91)90091-i
更新日期：1991-01-01 00:00:00
abstract：:Recent work (Shimojo, Silverman & Nakayama, 1989; Vision Research, 29, 619-626) suggests that the visual system must discriminate between extrinsic boundaries (boundaries created by front occluding surfaces) and intrinsic boundaries (real object boundaries) in order to recognize objects and that this would importantly...
journal_title：Vision research
pub_type： 杂志文章
doi：10.1016/0042-6989(91)90191-7
更新日期：1991-01-01 00:00:00
abstract：:Some blind humans use sound to navigate by emitting mouth-clicks and listening to the echoes that reflect from silent objects and surfaces in their surroundings. These echoes contain information about the size, shape, location, and material properties of objects. Here we present results from an fMRI experiment that in...
journal_title：Vision research
pub_type： 杂志文章
doi：10.1016/j.visres.2014.07.004
更新日期：2015-04-01 00:00:00
abstract：:The development of monocular and binocular grating acuity was measured in 87 infants, 2-52 weeks of age, using the sweep VEP technique. Average monocular and binocular acuity growth functions were nearly identical, with a small (less than 0.2 octaves) binocular acuity superiority occurring only under 6 months. Interoc...
journal_title：Vision research
pub_type： 杂志文章
doi：10.1016/0042-6989(89)90004-7
更新日期：1989-01-01 00:00:00
abstract：:Growth and decay characteristics of the tilt aftereffect were studied for aftereffects induced by normal or continuous adaptation routines, and for aftereffects induced by successive or spaced adaptation to the same or different orientations on an adapt-partial decay-readapt schedule. In the continuous adaptation cond...
journal_title：Vision research
pub_type： 杂志文章
doi：10.1016/0042-6989(86)90014-3
更新日期：1986-01-01 00:00:00
