The functional organisation of locust ocelli

  title={The functional organisation of locust ocelli},
  author={Martin Wilson},
  journal={Journal of comparative physiology},
  • Martin Wilson
  • Published 1 December 1978
  • Biology
  • Journal of comparative physiology
SummaryThis paper examines the optical and physiological organisation of locust ocelli with a view to understanding their function. The approach taken in this work has largely been to correlate quantitative measurements of the spectral, angular and absolute sensitivities of large second order neurons with radiometric data from the natural environment. The resulting estimates of the natural performance of these neurons form the basis for a hypothesis of their functional significance.1.In both… 

The mapping of visual space by dragonfly lateral ocelli

Dragonfly ocelli are adapted for high sensitivity as well as a modicum of resolution, especially in elevation, suggesting a role for attitude stabilisation by localization of the horizon.

Possible efference to the ocellar system of the locust and its effect on ocellar interneurons

  • S. Rotzler
  • Biology
    Journal of Comparative Physiology A
  • 2004
Summary1.Some units in the lateral ocellar nerves of the locust,Locusta migratoria, are influenced transsynaptically by the activity of ascending fibres in the thoracic connectives and therefore may

Visual interneurons in the bee brain: Synaptic organisation and transmission by graded potentials

Anatomical and electrophysiological evidence indicates that the output synapses can be “driven” directly by the graded potential without the intervention of spiking activity in the ocellar tract.

The mapping of visual space by identified large second-order neurons in the dragonfly median ocellus

Results provide the first evidence for the preservation of spatial information by the second-order neurons of any dorsal ocellus, which essentially forms a one-dimensional image of the equator over a wide azimuthal area, possibly forming an internal representation of the horizon.

The origin and properties of discrete hyperpolarising potentials in the second order cells of locust ocellus

It is concluded that discrete hyperpolarising potentials in L neurons are not the postsynaptic responses to single quanta of transmitter released from receptor terminals but are instead the result of discrete depolarisations in receptors.

The fine structure of the ocelli of Schistocerca gregaria

A study of the organisation of the locust dorsal ocellus shows that the structure is designed to provide the maximum possible effective aperture and there is an extensive lateral and feedback network between the receptors and interneurons.

Signal processing in a simple visual system: The locust ocellar system and its synapses

  • P. Simmons
  • Biology
    Microscopy research and technique
  • 2002
Electron microscopy has shown that each excitatory connection made from an L‐neuron to a postsynaptic partner consists of thousands of discrete synaptic contacts, in which individual dense‐staining bars in the presynaptic neuron are associated with clouds of vesicles.

Interactions made by large second-order neurones of the median ocellus of the locust

  • P. Simmons
  • Biology
    Journal of Comparative Physiology A
  • 2004
The median ocellus of a locust is connected with each lateral o cellus by a pair of neurones, called ML-neurones, which are probably capable of maintaining transmission for long periods, but the interactions are relatively weak.

The unusual visual system of the Strepsiptera: external eye and neuropils

Fluorescent fills, whole-tissue stains, and synaptotagmin immunohistochemistry show that the optic neuropils of this eye are densely packed, and that several parallel channels within the medulla underlie each of the lenses.



The function of the insect ocellus.

  • D. Parry
  • Biology
    The Journal of experimental biology
  • 1947
The object of the present research was to obtain more knowledge of the function of the ocellus, primarily by recording the nervous response to ocellar stimulation by using the migratory locust to provide a preparation just large enough for electrodes to be placed on the ocells and electrical changes occurring there to be amplified and recorded.

Functioning of the Insect Ocellar Nerve

The median ocellar nerve preparation of the locust Locusta migratoria has been re-investigated and disposes of the claim that the o cellar nerve exerts an effect on the brain as the result of electrotonic spread from a depolarized region in the ocellus.

Anatomy of locust ocellar interneurons: Constancy and variability

  • C. Goodman
  • Biology
    Journal of comparative physiology
  • 2004
The anatomy of the ocellar interneurons in the brain of the locust, Scchstocerca vaga, was revealed by axonal iontophoresis of cobalt chloride by finding major asymmetric variations in 9 of 50 preparations.

Organization of the retina of the mudpuppy, Necturus maculosus. II. Intracellular recording.

The intracellularly recorded response characteristics of each type of neuron in a vertebrate retina are described, and the response of each neuron to the responses of those neurons to which it is synaptically coupled are related.

Neural integration in the first optic neuropile of dragonflies

  • S. Laughlin
  • Biology
    Journal of comparative physiology
  • 2004
LMC's integrate retinal input by acting as high sensitivity detectors of contrast differences within the spatial domain by means of intracellular recordings from the retina and lamina of Hemicordulia tau.

Neural integration in the first optic neuropile of dragonflies

It is concluded that the retinula-LMC pathway acts, in thedark-adapted state as a high sensitivity detection system, and shows several adaptations to maximise the signal:noise ratio.

Electrophysiology of the Insect Dorsal Ocellus

  • P. Ruck
  • Biology
    The Journal of general physiology
  • 1961
Dorsal ocelli are small cup-like organs containing a layer of photoreceptor cells, the short axons of which synapse at the base of the cup with dendritic terminals of ocellar nerve fibers, which in dragonflies are spontaneously active, discharging afferent nerve impulses in the dark-adapted state.

Relationships between ocellar units in the ventral nerve cord and ocellar pathways in the brain ofSchistocerca gregaria

SummaryA study of the anatomy of the larger second-order neurones of the median and lateral ocelli of the locust, leads to a prediction of the types of third or higher order neurones which may be

Neural Organization of the Median Ocellus of the Dragonfly

It is suggested that enhanced photosensitivity of post Synaptic activity is a result of summation of many receptors onto the postsynaptic elements, and that transients in the post synaptic responses are related to the complex synaptic arrangements in the ocellar plexus to be described in the following paper.