Organization of local interneurons in optic glomeruli of the dipterous visual system and comparisons with the antennal lobes

2007 ◽  
Vol 67 (10) ◽  
pp. 1267-1288 ◽  
Author(s):  
Nicholas J. Strausfeld ◽  
Irina Sinakevitch ◽  
Jun-Ya Okamura

The antennal lobes of the moth Manduca sexta are composed of two distinct classes of central neurons: local interneurons, involved in sensory processing within the lobe, and output neurons, the relay elements carrying sensory information to higher neuropil centres in the brain. The different types of neurons in each class share many characteristics. All of the local interneurons have extensive multiglomerular dendritic arborizations and lack distinct axons while all of the output neurons have uniglomerular dendritic arborizations. In addition to these general characteristics the central neurons of the antennal lobes also possess a distinct sexual dimorphism. Only the male moth responds to the female sex pheromone. All of the central neurons in the antennal lobe of the male moth th at respond to pheromone have dendritic branches located in the macroglomerular complex, a male-specific neuropil region. Two types of pheromone-sensitive local interneurons have been described morphologically and physiologically while a single type of output neuron has been found that has a dendritic arborization in the macroglomerular complex.


2020 ◽  
Author(s):  
Samson Chengetanai ◽  
Adhil Bhagwandin ◽  
Mads F. Bertelsen ◽  
Therese Hård ◽  
Patrick R. Hof ◽  
...  

Author(s):  
Klaus-Ruediger Peters

Differential hysteresis processing is a new image processing technology that provides a tool for the display of image data information at any level of differential contrast resolution. This includes the maximum contrast resolution of the acquisition system which may be 1,000-times higher than that of the visual system (16 bit versus 6 bit). All microscopes acquire high precision contrasts at a level of <0.01-25% of the acquisition range in 16-bit - 8-bit data, but these contrasts are mostly invisible or only partially visible even in conventionally enhanced images. The processing principle of the differential hysteresis tool is based on hysteresis properties of intensity variations within an image.Differential hysteresis image processing moves a cursor of selected intensity range (hysteresis range) along lines through the image data reading each successive pixel intensity. The midpoint of the cursor provides the output data. If the intensity value of the following pixel falls outside of the actual cursor endpoint values, then the cursor follows the data either with its top or with its bottom, but if the pixels' intensity value falls within the cursor range, then the cursor maintains its intensity value.


1996 ◽  
Vol 1 (3) ◽  
pp. 200-205 ◽  
Author(s):  
Carlo Umiltà ◽  
Francesca Simion ◽  
Eloisa Valenza

Four experiments were aimed at elucidating some aspects of the preference for facelike patterns in newborns. Experiment 1 showed a preference for a stimulus whose components were located in the correct arrangement for a human face. Experiment 2 showed a preference for stimuli that had optimal sensory properties for the newborn visual system. Experiment 3 showed that babies directed their attention to a facelike pattern even when it was presented simultaneously with a non-facelike stimulus with optimal sensory properties. Experiment 4 showed the preference for facelike patterns in the temporal hemifield but not in the nasal hemifield. It was concluded that newborns' preference for facelike patterns reflects the activity of a subcortical system which is sensitive to the structural properties of the stimulus.


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