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651.
Roberto Chiussi 《Marine and Freshwater Behaviour and Physiology》2013,45(1):41-50
Behavioral responses of juveniles and adults of the mangrove crab Aratus pisonii (H. Milne Edwards, 1837) to black geometric shapes of equal surface area was measured. Crabs were tested either in presence or absence of chemicals generated from two common predator species, the portunid crab Callinectes ornatus Ordway, and the soapfish Haemulon aurolineatum Cuvier, 1830. The present study tested the hypothesis that A. pisonii (1) has the capacity to orient to visual cues; (2) it discriminates between different visual objects based on a combination of chemical and visual information and (3) this behavior changes with age. When presented with single black targets in background water, juveniles oriented toward all shapes. This behavioral response was interpreted as visual orientation toward potential shelter. Among shapes, juveniles showed preference for the vertical rectangle, probably due to the recognition of natural visual elements like mangrove roots. In predator conditioned water, juveniles exhibited a stronger response than in background water. Thus, juveniles were able to detect by odor the potential presence of predators. Change in responsiveness between adults and juveniles was also demonstrated. 相似文献
652.
S. Hochstein 《European biophysics journal : EBJ》1979,5(2-3):129-136
The characteristics of different responses of invertebrate photoreceptors are reviewed. Invertebrate photopigment bistability has made possible the functional operational dissection of the pigment transition scheme. Outlasting the usual stimulus-coincident late receptor potential (LRP), additional antagonistic responses have been found: the prolonged depolarizing after-potential (PDA) arising from a net rhodopsin to metarhodopsin pigment shift, and a PDA-depression and an anti-PDA effect which arise from a reverse shift and cancel the PDA when induced during or closely before it. The characteristics of these aftereffects and of the LRP are reviewed, analyzed and compared. Both potentials require rhodopsin activation and they share the characteristics of a common ionic conductance-change mechanism. However, for the LRP response to weak stimuli, no antagonistic metarhodopsin-dependent effect has been found analogous to PDA-depression and the anti-PDA. However, this is just the response level where interactive effects would be weakest. For more intense stimuli, pigment-state effects on the shape of the LRP have been found, and net pigment shifts affect the strength of a facilitatory effect.Based on material presented at the European Neurosciences Meeting, Florence, September 1978 相似文献
653.
Dynamic Changes of Serotonin Levels During the First Visual Experience of Binocularly Deprived Kittens 总被引:1,自引:1,他引:0
Malgorzata Kossut Magdalena Wójcik Jolanta Skangiel-Kramska 《Journal of neurochemistry》1981,37(5):1077-1080
Abstract— Kittens deprived of pattern vision until the 28th day of life received monocular visual experience for 3, 6, 14, and 75 h. Biphasic response of serotonin was found in the visual cortex. Stimulation for 3 h resulted in an increase of serotonin level whereas at 14 h it produced a decrease. The effects are transient, no longer observable after 75 h stimulation. No changes were observed in somatosensory cortex. 相似文献
654.
Activation of cGMP phosphodiesterase(PDE) of frog rod outer segments (ROS) by purified green rod pigment (GRP) was analyzed. GRP activated PDE in a similar manner to purified rhodopsin. This activation required illumination of the pigment and presence of GTP. 相似文献
655.
In this study, we describe a model of motion integration in smooth eye pursuit based on a recursive Bayesian estimation process,
which displays a dynamic behaviour qualitatively similar to the dynamics of the motion integration process observed experimentally,
both psychophysically in humans and monkeys, and physiologically in monkeys. By formulating the model as an approximate version
of a Kalman filter algorithm, we have been able to show that it can be put into a neurally plausible, distributed recurrent
form which coarsely corresponds to the recurrent circuitry of visual cortical areas V1 and MT. The model thus provides further
support for the notion that the motion integration process is based on a form of Bayesian estimation, as has been suggested
by many psychophysical studies, and moreover suggests that the observed dynamic properties of this process are the result
of the recursive nature of the motion estimation. 相似文献
656.
Previous studies have shown that Nogo-NgR system plays multiple roles in controlling axonal regeneration and neuronal plasticity.
However, the investigation on the distributions of Nogo and NgR was limited to restricted areas or special ages, and their
expression patterns in the neonatal visual nervous system is still unknown. Frozen sections were made from eyeballs and brains
of three neonatal rats, and expression of Nogo and NgR proteins were examined by immunofluorescence under a laser confocal
microscopy. Nogo and NgR were observed to express in the cell bodies of retina, lateral geniculate bodies and visual cortex
of the neonatal rats. Our results provide evidences that the Nogo-NgR system may play an active role in the plasticity of
neonatal visual system.
Y. Xiaolei, Y. Rongdi and J. Shuxing contributed equally to this work. 相似文献
657.
The ability to see colors is not universal in the animal kingdom. Those animals that can detect differences in the wavelengths
of the electromagnetic spectrum glean valuable sensory information about their environment. They use color vision to forage,
avoid predators, and find high-quality mates. In the past, the colors that humans could see clouded scientists’ study of animals’
color perception. Leaving that bias behind has led to new insights about how and why the color vision of animals evolved.
This paper provides a brief introduction to color vision, the genetics of color vision in humans, what colors other animals
see, and how scientists study color vision. We examine the consequences of having color vision, including speciation, loss
of olfactory capabilities, and sexual selection. 相似文献
658.
Barbara Wiggert Julia E. Derr Michael Fitzpatrick Gerald J. Chader 《Biochimica et Biophysica Acta (BBA)/General Subjects》1979,582(1):115-121
Vitamin A receptors of the retina appear to be differentially extractable in light and in dark suggesting that they could function as inter- or intra-cellular transport vehicles in the visual cycle. 相似文献
659.
Lonnie R. Sherrod 《Human nature (Hawthorne, N.Y.)》1990,1(4):331-353
The study of infant social cognition is the study of how human infants acquire information about people. By examining infants’
sensory abilities and the stimulus characteristics of people, research can determine what information is available to infants
from their social world. We can then consider what social environments are appropriate for infants of different ages. This
paper examines the sociocognitive competencies of human infants during the first 6 months of their lives and asks how these
competencies are functional in the daily social ecology of the human infant. Select examples of research with other species
are used to illustrate how the adaptive significance of sociocognitive abilities could be more fruitfully explored in studies
of human infancy.
Lonnie R. Sherrod is Vice President for Program at the William T. Grant Foundation. Formerly, he was Assistant Dean at the
Graduate Faculty of the New School for Social Research and before that, Staff Associate at the Social Science Research Council.
He received a Ph.D. in Developmental Psychology from Yale University in 1978, an M.A. in Biology from the University of Rochester
in 1974; and a B.A. in Zoology and Psychology from Duke University in 1972. He has taught at New York University and the New
School and has published numerous articles and edited volumes on infant social cognition, on adolescence, and on child development
from a life-span and biosocial perspective. Examples includeInfant Social Cognition (1981), edited with Michael Lamb;The Life Course and Human Development: Multidisciplinary Perspectives (1986), edited with Aage B. Sorensen and Franz E. Weinert; and “Changes in Children’s Social Lives and the Development of
Social Understanding” authored with Judith Dunn (1988), in E.M. Hetherington, M. Perlmutter, and R. Lerner (eds).,Child Development in Life-Span Perspective. 相似文献
660.
Darrell. J. Kemp 《Journal of Insect Behavior》2006,19(5):669-684
Ultraviolet (UV) colour patterns, particularly those deriving from surface structures, serve a role in sexual signalling and mate choice in a range of animal groups. In the butterfly Colias eurytheme (Pieridae), male-limited iridescent UV functions in species recognition, and has potential as an intraspecific sexual signal of mate quality. I compared the dorsal colouration and body size of males discovered ‘in-copula’ (N = 95) with a random sample of free-flying individuals (N = 129), both collected from a high density agricultural population located in Chandler, U.S.A. Despite reasonable variance in each trait, I found no among-group differences in UV characters (brightness, hue and angular visibility) or in the coincident pigmentary yellowish-orange (brightness and saturation). Statistical power was sufficient to detect all but the smallest among-group differences, and there was a marginally significant tendency for in-copula males to be larger. These data do not support the hypothesis for intraspecific female choice upon male dorsal colouration. However, I discuss how the density and apparently very young age of individuals in the sampling population may have pre-disposed this result, and thus, how sexual selection on male colouration may operate in a density dependent manner. 相似文献