Different functions of different eye types in the spider Cupiennius salei.

1998 ◽  
Vol 201 (2) ◽  
pp. 221-225 ◽  
Author(s):  
A Schmid
Keyword(s):  
Visual Information ◽  
Mating Behaviour ◽  
Visual Fields ◽  
Cupiennius Salei ◽  
Posterior Median ◽  
Simultaneous Choice ◽  
Target Detecting ◽  
Spider Cupiennius Salei ◽  
Median Eyes ◽  
Anterior Median

The Central American hunting spider Cupiennius salei Keys relies mainly on its mechanosensory systems during prey-catching and mating behaviour. The behavioural relevance of its eight eyes has not been studied before, although their optics and sensitivity suggest highly developed visual capabilities. The visual system was examined in a twofold simultaneous-choice experiment. Two targets were presented at a distance of 2 m from the animals, and their walking paths towards the targets were monitored. Spiders showed no preference when choosing between two identical targets, but when choosing between two different targets they strongly preferred a vertical bar to a sloping bar or a V-shaped target. By covering all eyes except the anterior median or posterior median eyes, it could be shown that the spiders were able to detect the targets using any of the eyes. Discrimination between different targets was only possible with the anterior median eyes uncovered, although the visual fields of the anterior median and posterior median eyes overlap completely. It seems most likely that the animals separate visual information in the periphery and therefore that the eyes have different functions. The posterior median eyes support a target-detecting mechanism and the anterior median eyes a target-discrimination mechanism.

scholarly journals Visual pathways in the brain of the jumping spider Marpissa muscosa

2019 ◽  
Author(s):  
Philip O.M. Steinhoff ◽  
Gabriele Uhl ◽  
Steffen Harzsch ◽  
Andy Sombke
Keyword(s):  
Visual Fields ◽  
Visual Pathways ◽  
Second Order ◽  
Jumping Spider ◽  
Cupiennius Salei ◽  
First Order ◽  
Posterior Median ◽  
Eye Size ◽  
The Brain ◽  
Median Eyes

AbstractSome animals have evolved task differentiation among their eyes. A particular example is spiders, where most species have eight eyes, of which two (the principal eyes) are used for object discrimination, whereas the other three pairs (secondary eyes) detect movement. In the spider species Cupiennius salei these two eye types correspond to two visual pathways in the brain. Each eye is associated with its own first and second order visual neuropil. The second order neuropils of the principal eyes are connected to the arcuate body, whereas the second order neuropils of the secondary eyes are linked to the mushroom body. However, eye size and visual fields are considerably different in jumping spiders. We explored the principal- and secondary eye visual pathways of the jumping spider Marpissa muscosa. We found that the connectivity of the principal eye pathway is the same as in C. salei, while there are differences in the secondary eye pathways. In M. muscosa, all secondary eyes are connected to their own first order visual neuropils. The first order visual neuropils of the anterior lateral and posterior lateral eyes are further connected with two second order visual neuropils, whereas the posterior median eyes lack second order visual neuropils and their axons project only to the arcuate body. This suggests that the posterior median eyes probably do not serve movement detection in M. muscosa. Furthermore, the second order visual neuropil (L2) in Marpissa muscosa potentially integrates information from the secondary eyes and might thus enable faster movement decisions.

THE QUALITY OF VISION IN THE CTENID SPIDER CUPIENNIUS SALEI

1992 ◽  
Vol 164 (1) ◽  
pp. 227-242 ◽  
Author(s):  
M. F. LAND ◽  
F. G. BARTH
Keyword(s):  
Predator Avoidance ◽  
Prey Capture ◽  
Cupiennius Salei ◽  
Quality Of Vision ◽  
Visual Behaviour ◽  
Similar Range ◽  
Retinal Resolution ◽  
Spider Cupiennius Salei ◽  
Median Eyes

Much is known about the mechanosensory behaviour of the spider Cupiennius Keyserling, but much less about its visual capabilities. In this study the quality of the optical image, the retinal resolution and the fields of view were assessed for each of the four pairs of eyes. The image is of good quality in all eyes. The principal (antero-median) eyes lack a tapetum and have an inter-receptor angle of 2.9°. The three secondary eyes (antero-lateral, postero-median and posterolateral) all have ‘gridiron’ tapeta with receptors arranged in rows. The angular separations (along rows × between rows) are 3.6° × 9.3°, 0.9° × 2.3° and 1.0° × 3.0°, respectively. Although the disposition of eyes on the head is similar to that of pisaurid spiders, all other features of the eyes, including the sizes and shapes of the fields of view, resemble those of lycosid spiders. The peripheral visual system of Cupiennius can thus, in principle, support a similar range of visual behaviour to that of lycosids, which includes prey capture, predator avoidance and courtship.

scholarly journals Cuttlefish use stereopsis to strike at prey

2020 ◽  
Vol 6 (2) ◽  
pp. eaay6036 ◽  
Author(s):  
R. C. Feord ◽  
M. E. Sumner ◽  
S. Pusdekar ◽  
L. Kalra ◽  
P. T. Gonzalez-Bellido ◽  
...  
Keyword(s):  
Information Processing ◽  
Visual Information ◽  
Convergent Evolution ◽  
Visual Fields ◽  
Three Dimensional ◽  
Visual Information Processing ◽  
Depth Information ◽  
Cephalopod Species ◽  
Left And Right

The camera-type eyes of vertebrates and cephalopods exhibit remarkable convergence, but it is currently unknown whether the mechanisms for visual information processing in these brains, which exhibit wildly disparate architecture, are also shared. To investigate stereopsis in a cephalopod species, we affixed “anaglyph” glasses to cuttlefish and used a three-dimensional perception paradigm. We show that (i) cuttlefish have also evolved stereopsis (i.e., the ability to extract depth information from the disparity between left and right visual fields); (ii) when stereopsis information is intact, the time and distance covered before striking at a target are shorter; (iii) stereopsis in cuttlefish works differently to vertebrates, as cuttlefish can extract stereopsis cues from anticorrelated stimuli. These findings demonstrate that although there is convergent evolution in depth computation, cuttlefish stereopsis is likely afforded by a different algorithm than in humans, and not just a different implementation.

Responses of cells in the tail of the caudate nucleus during visual discrimination learning

1995 ◽  
Vol 74 (3) ◽  
pp. 1083-1094 ◽  
Author(s):  
V. J. Brown ◽  
R. Desimone ◽  
M. Mishkin
Keyword(s):  
Caudate Nucleus ◽  
Visual Discrimination ◽  
Visual Information ◽  
Visual Learning ◽  
Visual Fields ◽  
Receptive Fields ◽  
Visual Responses ◽  
Neuronal Responses ◽  
Association Learning ◽  
Visual Properties

1. The tail of the caudate nucleus and adjacent ventral putamen (ventrocaudal neostriatum) are major projection sites of the extrastriate visual cortex. Visual information is then relayed, directly or indirectly, to a variety of structures with motor functions. To test for a role of the ventrocaudal neostriatum in stimulus-response association learning, or habit formation, neuronal responses were recorded while monkeys performed a visual discrimination task. Additional data were collected from cells in cortical area TF, which serve as a comparison and control for the caudate data. 2. Two monkeys were trained to perform an asymmetrically reinforced go-no go visual discrimination. The stimuli were complex colored patterns, randomly assigned to be either positive or negative. The monkey was rewarded with juice for releasing a bar when a positive stimulus was presented, whereas a negative stimulus signaled that no reward was available and that the monkey should withhold its response. Neuronal responses were recorded both while the monkey performed the task with previously learned stimuli and while it learned the task with new stimuli. In some cases, responses were recorded during reversal learning. 3. There was no evidence that cells in the ventrocaudal neostriatum were influenced by the reward contingencies of the task. Cells did not fire preferentially to the onset of either positive or negative stimuli; neither did cells fire in response to the reward itself or in association with the motor response of the monkey. Only visual responses were apparent. 4. The visual properties of cells in these structures resembled those of cells in some of the cortical areas projecting to them. Most cells responded selectively to different visual stimuli. The degree of stimulus selectivity was assessed with discriminant analysis and was found to be quantitatively similar to that of inferior temporal cells tested with similar stimuli. Likewise, like inferior temporal cells, many cells in the ventrocaudal neostriatum had large, bilateral receptive fields. Some cells had "doughnut"-shaped receptive fields, with stronger responses in the periphery of both visual fields than at the fovea, similar to the fields of some cells in the superior temporal polysensory area. Although the absence of task-specific responses argues that ventrocaudal neostriatal cells are not themselves the mediators of visual learning in the task employed, their cortical-like visual properties suggest that they might relay visual information important for visuomotor plasticity in other structures. (ABSTRACT TRUNCATED AT 400 WORDS)

scholarly journals Representation of the Ipsilateral Visual Field by Neurons in the Macaque Lateral Intraparietal Cortex Depends on the Forebrain Commissures

2010 ◽  
Vol 104 (5) ◽  
pp. 2624-2633 ◽  
Author(s):  
Catherine A. Dunn ◽  
Carol L. Colby
Keyword(s):  
Receptive Field ◽  
Eye Movement ◽  
Visual Information ◽  
Visual Fields ◽  
Receptive Fields ◽  
Neural Mechanism ◽  
Brain Regions ◽  
Spatial Updating ◽  
Split Brain ◽  
Lateral Intraparietal Cortex

Our eyes are constantly moving, allowing us to attend to different visual objects in the environment. With each eye movement, a given object activates an entirely new set of visual neurons, yet we perceive a stable scene. One neural mechanism that may contribute to visual stability is remapping. Neurons in several brain regions respond to visual stimuli presented outside the receptive field when an eye movement brings the stimulated location into the receptive field. The stored representation of a visual stimulus is remapped, or updated, in conjunction with the saccade. Remapping depends on neurons being able to receive visual information from outside the classic receptive field. In previous studies, we asked whether remapping across hemifields depends on the forebrain commissures. We found that, when the forebrain commissures are transected, behavior dependent on accurate spatial updating is initially impaired but recovers over time. Moreover, neurons in lateral intraparietal cortex (LIP) continue to remap information across hemifields in the absence of the forebrain commissures. One possible explanation for the preserved across-hemifield remapping in split-brain animals is that neurons in a single hemisphere could represent visual information from both visual fields. In the present study, we measured receptive fields of LIP neurons in split-brain monkeys and compared them with receptive fields in intact monkeys. We found a small number of neurons with bilateral receptive fields in the intact monkeys. In contrast, we found no such neurons in the split-brain animals. We conclude that bilateral representations in area LIP following forebrain commissures transection cannot account for remapping across hemifields.

Intracellular characterization of identified sensory cells in a new spider mechanoreceptor preparation

1994 ◽  
Vol 71 (4) ◽  
pp. 1422-1427 ◽  
Author(s):  
E. A. Seyfarth ◽  
A. S. French
Keyword(s):  
Sensory Neurons ◽  
Action Potentials ◽  
Lucifer Yellow ◽  
Sense Organ ◽  
Sensory Cells ◽  
Cupiennius Salei ◽  
Bursting Neuron ◽  
Sensory Structures ◽  
Spider Cupiennius Salei

1. We have developed an isolated mechanoreceptor-organ preparation in which the intact sensory structures are available for mechanical stimulation and electrical recording. The anterior lyriform slit sense organ on the patella of the spider, Cupiennius salei Keys., consists of seven or eight cuticular slits, each innervated by a pair of large bipolar sensory neurons. The neurons are fusiform, and the largest somata are < or = 120 microns long. The innervation of the organ was characterized by light microscopy of neurons backfilled with neuronal tracers. Intracellular recording was used to measure the passive and active electrical properties of the neurons, in several cases followed by identification with Lucifer yellow injection. Both neurons of each pair from one slit responded with action potentials to depolarization by a step current injection. Approximately half of the sensory neurons adapted very rapidly and generated only one or two action potentials in response to a sustained depolarizing step, while a second group produced a burst of action potentials that adapted to silence in approximately 1 s or less. Recordings from identified neuron pairs indicated that each pair consists of one rapidly adapting and one bursting neuron. Measurements of cell membrane impedances and time constants produced estimates of neuronal size that agreed with the morphological measurements. This new preparation offers the possibility of characterizing the mechanisms underlying transduction and adaptation in primary mechanosensory neurons.

Sign in / Sign up

Export Citation Format

Share Document