Serotonergic modulation of visual neurons in Drosophila melanogaster

AbstractSensory systems rely on neuromodulators, such as serotonin, to provide flexibility for information processing in the face of a highly variable stimulus space. Serotonergic neurons broadly innervate the optic ganglia of Drosophila melanogaster, a widely used model for studying vision. The role for serotonergic signaling in the Drosophila optic lobe and the mechanisms by which serotonin regulates visual neurons remain unclear. Here we map the expression patterns of serotonin receptors in the visual system, focusing on a subset of cells with processes in the first optic ganglion, the lamina, and show that serotonin can modulate visual responses. Serotonin receptors are expressed in several types of columnar cells in the lamina including 5-HT2B in lamina monopolar cell L2, required for the initial steps of visual processing, and both 5-HT1A and 5-HT1B in T1 cells, whose function is unknown. Subcellular mapping with GFP-tagged 5-HT2B and 5-HT1A constructs indicates that these receptors localize to layer M2 of the medulla, proximal to serotonergic boutons, suggesting that the medulla is the primary site of serotonergic regulation for these neurons. Serotonin increases intracellular calcium in L2 terminals in layer M2 and alters the kinetics of visually induced calcium transients in L2 neurons following dark flashes. These effects were not observed in flies without a functional 5-HT2B, which displayed severe differences in the amplitude and kinetics of their calcium response to both dark and light flashes. While we did not detect serotonin receptor expression in L1 neurons, they also undergo serotonin-induced calcium changes, presumably via cell non-autonomous signaling pathways. We provide the first functional data showing a role for serotonergic neuromodulation of neurons required for initiating visual processing in Drosophila and establish a new platform for investigating the serotonergic neuromodulation of sensory networks.Author SummarySerotonergic neurons innervate the Drosophila melanogaster eye, but the function of serotonergic signaling is not known. We found that serotonin receptors are expressed in all neuropils of the optic lobe and identify specific neurons involved in visual information processing that express serotonin receptors. We then demonstrate that activation of these receptors can alter how visual information is processed. These are the first data suggesting a functional role for serotonergic signaling in Drosophila vision. This study contributes to the understanding of serotonin biology and modulation of sensory circuits.

Download Full-text

Effects of Symbol Structure on Visual Information Processing

Proceedings of the Human Factors Society Annual Meeting ◽

10.1177/154193128302700503 ◽

1983 ◽

Vol 27 (5) ◽

pp. 354-354

Author(s):

Bruce W. Hamill ◽

Robert A. Virzi

Keyword(s):

Information Processing ◽

Visual Processing ◽

Visual Information ◽

Context Effects ◽

Response Times ◽

Search Time ◽

Visual Information Processing ◽

Array Size ◽

Serial Search ◽

Feature Structure

This investigation addresses the problem of attention in the processing of symbolic information from visual displays. Its scope includes the nature of attentive processes, the structural properties of stimuli that influence visual information processing mechanisms, and the manner in which these factors interact in perception. Our purpose is to determine the effects of configural feature structure on visual information processing. It is known that for stimuli comprising separable features, one can distinguish between conditions in which only one relevant feature differs among stimuli in the array being searched and conditions in which conjunctions of two (or more) features differ: Since the visual process of conjoining separable features is additive, this fact is reflected in search time as a function of array size, with feature conditions yielding flat curves associated with parallel search (no increase in search time across array sizes) and conjunction conditions yielding linearly increasing curves associated with serial search. We studied configural-feature stimuli within this framework to determine the nature of visual processing for such stimuli as a function of their feature structure. Response times of subjects searching for particular targets among structured arrays of distractors were measured in a speeded visual search task. Two different sets of stimulus materials were studied in array sizes of up to 32 stimuli, using both tachistoscope and microcomputer-based CRT presentation for each. Our results with configural stimuli indicate serial search in all of the conditions, with the slope of the response-time-by-array-size function being steeper for conjunction conditions than for feature conditions. However, for each of the two sets of stimuli we studied, there was one configuration that stood apart from the others in its set in that it yielded significantly faster response times, and in that conjunction conditions involving these particular stimuli tended to cluster with the feature conditions rather than with the other conjunction conditions. In addition to these major effects of particular targets, context effects also appeared in our results as effects of the various distractor sets used; certain of these context effects appear to be reversible. The effects of distractor sets on target search were studied in considerable detail. We have found interesting differences in visual processing between stimuli comprising separable features and those comprising configural features. We have also been able to characterize the effects we have found with configural-feature stimuli as being related to the specific feature structure of the target stimulus in the context of the specific feature structure of distractor stimuli. These findings have strong implications for the design of symbology that can enhance visual performance in the use of automated displays.

Download Full-text

CVI Experience toolbox: Simulation of visual processing difficulties

British Journal of Visual Impairment ◽

10.1177/0264619619869044 ◽

2019 ◽

Vol 37 (3) ◽

pp. 248-257

Author(s):

Florine Pilon-Kamsteeg ◽

Marjoke J Dekker-Pap ◽

Gerard C de Wit ◽

Maria M van Genderen

Keyword(s):

Information Processing ◽

Visual Impairment ◽

Visual Processing ◽

Visual Information ◽

Visual Information Processing ◽

Previous Experience ◽

Added Value ◽

Slide Presentation ◽

Cerebral Visual Impairment ◽

Simulation Exercises

We designed a cerebral visual impairment (CVI)–experience toolbox containing simulation exercises to let professionals experience the complexity of visual information processing and to get an impression of what it means to have CVI. We measured the benefits of the CVI Experience toolbox by using questionnaires during three CVI seminars with professionals ( n = 69). These seminars started with a slide presentation on CVI followed by the CVI experience toolbox. We presented the professionals with the same survey on their knowledge of CVI at the start of the seminar, after the presentation, and after the toolbox. Professionals with more previous CVI experience started on average with a higher score. The final end score, however, did not seem to depend on previous experience. Furthermore, the added value of the experience toolset was quite independent of the added value of the presentation. The results indicate that both the presentationand the experience toolboxadd to the understanding of CVI.

Download Full-text

Circadian Control of Visual Information Processing in the Optic Lobe of the Giant Cockroach Blaberus giganteus

Journal of Biological Rhythms ◽

10.1177/074873049300800404 ◽

1993 ◽

Vol 8 (4) ◽

pp. 311-323 ◽

Cited By ~ 8

Author(s):

R. Bult ◽

H.A.K. Mastebroek

Keyword(s):

Information Processing ◽

Visual Information ◽

Optic Lobe ◽

Visual Information Processing ◽

Circadian Control

Download Full-text

Dysfunction of Magnocellular/dorsal Processing Stream in Schizophrenia

Current Psychiatry Research and Reviews ◽

10.2174/1573400515666190119163522 ◽

2019 ◽

Vol 15 (1) ◽

pp. 26-36

Author(s):

Sergio Chieffi

Keyword(s):

Information Processing ◽

Visual Processing ◽

Visual Information ◽

Visual Information Processing ◽

Contour Detection ◽

Backward Masking ◽

Dorsal Pathway ◽

Processing Stream ◽

Early Processing ◽

Processing Of Visual Information

Background: Patients with schizophrenia show not only cognitive, but also perceptual deficits. Perceptual deficits may affect different sensory modalities. Among these, the impairment of visual information processing is of particular relevance as demonstrated by the high incidence of visual disturbances. In recent years, the study of neurophysiological mechanisms that underlie visuo-perceptual, -spatial and -motor disorders in schizophrenia has increasingly attracted the interest of researchers. Objective: The study aims to review the existent literature on magnocellular/dorsal (occipitoparietal) visual processing stream impairment in schizophrenia. The impairment of relatively early stages of visual information processing was examined using experimental paradigms such as backward masking, contrast sensitivity, contour detection, and perceptual closure. The deficits of late processing stages were detected by examining visuo-spatial and -motor abilities. Results: Neurophysiological and behavioral studies support the existence of deficits in the processing of visual information along the magnocellular/dorsal pathway. These deficits appear to affect both early and late stages of visual information processing. Conclusion: The existence of disturbances in the early processing of visual information along the magnocellular/dorsal pathway is strongly supported by neurophysiological and behavioral observations. Early magnocellular dysfunction may provide a substrate for late dorsal processing impairment as well as higher-level cognition deficits.

Download Full-text

Visual input into the Drosophila melanogaster mushroom body

10.1101/2020.02.07.935924 ◽

2020 ◽

Cited By ~ 2

Author(s):

Jinzhi Li ◽

Brennan Dale Mahoney ◽

Miles Solomon Jacob ◽

Sophie Jeanne Cécile Caron

Keyword(s):

Drosophila Melanogaster ◽

Multisensory Integration ◽

Visual Processing ◽

Visual Information ◽

Mushroom Body ◽

Fundamental Property ◽

Sensory Systems ◽

Connectivity Pattern ◽

Ideal System ◽

Genetic Techniques

ABSTRACTThe ability to integrate input from different sensory systems is a fundamental property of many brains. Yet, the patterns of neuronal connectivity that underlie such multisensory integration remain poorly characterized. The Drosophila melanogaster mushroom body — an associative center required for the formation of olfactory and visual memories — is an ideal system to investigate how different sensory channels converge in higher-order brain centers. The neurons connecting the mushroom body to the olfactory system have been described in great detail, but input from other sensory systems remains poorly defined. Here, we use a range of anatomical and genetic techniques to identify two novel types of mushroom body input neuron that connect visual processing centers — namely the lobula and the posterior lateral protocerebrum — to the dorsal accessory calyx of the mushroom body. Together with previous work that described a pathway conveying visual information from the medulla to the ventral accessory calyx of the mushroom body (Vogt et al., 2016), our study defines a second, parallel pathway that is anatomically poised to convey information from the visual system to the dorsal accessory calyx. This connectivity pattern — the segregation of the visual information into two separate pathways — could be a fundamental feature of the neuronal architecture underlying multisensory integration in associative brain centers.

Download Full-text

Cellular organization of visual information processing channels in the mouse visual cortex

10.1101/441014 ◽

2018 ◽

Cited By ~ 3

Author(s):

Xu Han ◽

Ben Vermaercke ◽

Vincent Bonin

Keyword(s):

Information Processing ◽

Functional Diversity ◽

Visual Processing ◽

Visual Information ◽

Visual Representations ◽

Data Sets ◽

Visual Areas ◽

Motion Speed ◽

Information Channels ◽

Spatiotemporal Tuning

AbstractVisual processing and behavior depend on specialized neural representations and information channels that encode distinct visual information and enable distinct computations. Our understanding of the neural substrate, however, remain severely limited by sparse recordings and the restricted range of visual areas and visual stimuli considered. We characterized in the mouse the multidimensional spatiotemporal tuning properties of > 30,000 layer 2/3 pyramidal neurons across seven areas of the cortex. The dataset reveals population specialized for processing of oriented and non-oriented contrast, spatiotemporal frequency, and motion speed. Areal analysis reveals profound functional diversity and specificity as well as highly specific representations of visual processing channels in distinct visual areas. Clustering analysis shows a branching of visual representations along the posterior to anterior axis, and between lateral and dorsal areas. Overall, this dataset provides a cellular-resolution atlas for understanding organizing principles underlying sensory representations across the cortex.SummaryVisual representations and visual channels are the cornerstones of mammalian visual processing and critical for a range of life sustaining behaviors. However, the lack of data sets spanning multiple visual areas preclude unambiguous identification of visual processing streams and the sparse, singular recording data sets obtained thus far are insufficient to reveal the functional diversity of visual areas and to study visual information channels. We characterized the tunings of over 30,000 cortical excitatory neurons from 7 visual areas to a broad array of stimuli and studied their responses in terms of their ability to encode orientation, spatiotemporal contrast and visual motion speed. We found all mouse visual cortical areas convey diverse information but show distinct biases in terms of numbers of neurons tuned to particular spatiotemporal features. Neurons in visual areas differ in their spatiotemporal tuning but also in their relative response to oriented and unoriented contrast. We uncovered a population that preferentially responds to unoriented contrast and shows only weak responses to oriented stimuli. This population is strongly overrepresented in certain areas (V1, LM and LI) and underrepresented in others (AL, RL, AM, and PM). Spatiotemporal tunings are broadly distributed in all visual areas indicating that all areas have access to broad spatiotemporal information. However, individual areas show specific biases. While V1 is heavily biased in favor of low spatial and temporal frequencies, area LM responds more strongly to mid-range frequencies. Areas PM and LI are biased in favor of slowly-varying high-resolution signals. By comparison, anterior areas AL, RL and AM are heavily biased in favor of fast-varying, low to mid spatial frequency signals. Critically, theses biases express themselves in vastly different number of cells tuned to particular features, suggesting differential sampling of visual processing channels across areas. Comparing across areas, we found divergent visual representations between anterior and posterior areas, and between lateral and dorsal areas, suggesting the segregated organization of cortical streams for distinct information processing.

Download Full-text

Maturation of Early Visual Processing Investigated by a Pattern-Reversal Habituation Paradigm is Altered in Migraine

Cephalalgia ◽

10.1111/j.1468-2982.2004.00853.x ◽

2005 ◽

Vol 25 (4) ◽

pp. 280-289 ◽

Cited By ~ 32

Author(s):

R Oelkers-Ax ◽

P Parzer ◽

F Resch ◽

M Weisbrod

Keyword(s):

Information Processing ◽

Visual Processing ◽

Visual Information ◽

Primary Headache ◽

Tension Type Headache ◽

Event Related Potential ◽

Pattern Reversal ◽

Latency Reduction ◽

Early Visual Processing ◽

Type Headache

Evidence for a disturbed maturation of information processing in migraine came recently from evoked and event-related potential studies during childhood. In adult migraineurs, deficient habituation is proposed as principal interictal abnormality and was found inter alia for Visual Evoked Potentials (VEPs). This study investigated response and habituation to pattern-reversal VEPs and its maturation in 102 children with primary headache (migraine with and without aura, tension-type headache) and 79 healthy controls from 6 to 18 years. A reduction of N180 latency from pre- to postpubertal age reflects maturation and was clearly present in controls but lessened in migraineurs. N180 latency was prolonged in migraineurs without aura from 12 years onwards. Habituation did not differ between groups. In conclusion, diminished N180 latency reduction with age in migraineurs gives further evidence that maturation of visual information processing is altered in migraine. Deficient habituation to pattern-reversal VEPs could not be confirmed during childhood migraine.

Download Full-text

Anomalous visual experiences, negative symptoms, perceptual organization and the magnocellular pathway in schizophrenia: a shared construct?

Psychological Medicine ◽

10.1017/s0033291705005398 ◽

2005 ◽

Vol 35 (10) ◽

pp. 1445-1455 ◽

Cited By ~ 48

Author(s):

SZABOLCS KÉRI ◽

IMRE KISS ◽

OGUZ KELEMEN ◽

GYÖRGY BENEDEK ◽

ZOLTÁN JANKA

Keyword(s):

Information Processing ◽

Perceptual Organization ◽

Visual Processing ◽

Visual Information ◽

Negative Symptoms ◽

Performance Test ◽

Visual Information Processing ◽

Natural Image ◽

Adult Intelligence Scale ◽

Rapid Visual Processing

Background. Schizophrenia is associated with impaired visual information processing. The aim of this study was to investigate the relationship between anomalous perceptual experiences, positive and negative symptoms, perceptual organization, rapid categorization of natural images and magnocellular (M) and parvocellular (P) visual pathway functioning.Method. Thirty-five unmedicated patients with schizophrenia and 20 matched healthy control volunteers participated. Anomalous perceptual experiences were assessed with the Bonn Scale for the Assessment Basic Symptoms (BSABS). General intellectual functions were evaluated with the revised version of the Wechsler Adult Intelligence Scale. The 1–9 version of the Continuous Performance Test (CPT) was used to investigate sustained attention. The following psychophysical tests were used: detection of Gabor patches with collinear and orthogonal flankers (perceptual organization), categorization of briefly presented natural scenes (rapid visual processing), low-contrast and frequency-doubling vernier threshold (M pathway functioning), isoluminant colour vernier threshold and high spatial frequency discrimination (P pathway functioning).Results. The patients with schizophrenia were impaired on test of perceptual organization, rapid visual processing and M pathway functioning. There was a significant correlation between BSABS scores, negative symptoms, perceptual organization, rapid visual processing and M pathway functioning. Positive symptoms, IQ, CPT and P pathway measures did not correlate with these parameters. The best predictor of the BSABS score was the perceptual organization deficit.Conclusions. These results raise the possibility that multiple facets of visual information processing deficits can be explained by M pathway dysfunctions in schizophrenia, resulting in impaired attentional modulation of perceptual organization and of natural image categorization.

Download Full-text