Hawkmoth lamina monopolar cells act as dynamic spatial filters to optimize vision at different light levels

Anna Lisa Stöckl; David Charles O’Carroll; Eric James Warrant

doi:10.1126/sciadv.aaz8645

Hawkmoth lamina monopolar cells act as dynamic spatial filters to optimize vision at different light levels

Science Advances ◽

10.1126/sciadv.aaz8645 ◽

2020 ◽

Vol 6 (16) ◽

pp. eaaz8645 ◽

Cited By ~ 6

Author(s):

Anna Lisa Stöckl ◽

David Charles O’Carroll ◽

Eric James Warrant

Keyword(s):

Visual Information ◽

Receptive Fields ◽

Dendritic Morphology ◽

Spatial Filters ◽

Form And Function ◽

Light Levels ◽

Macroglossum Stellatarum ◽

Lateral Extent ◽

And Function ◽

Higher Sensitivity

How neural form and function are connected is a central question of neuroscience. One prominent functional hypothesis, from the beginnings of neuroanatomical study, states that laterally extending dendrites of insect lamina monopolar cells (LMCs) spatially integrate visual information. We provide the first direct functional evidence for this hypothesis using intracellular recordings from type II LMCs in the hawkmoth Macroglossum stellatarum. We show that their spatial receptive fields broaden with decreasing light intensities, thus trading spatial resolution for higher sensitivity. These dynamic changes in LMC spatial properties can be explained by the density and lateral extent of their dendritic arborizations. Our results thus provide the first physiological evidence for a century-old hypothesis, directly correlating physiological response properties with distinctive dendritic morphology.

Download Full-text

Form and Function of Facial Expressive Origins

10.1093/acprof:oso/9780190613501.003.0010 ◽

2017 ◽

Author(s):

Daniel H. Lee ◽

Adam K. Anderson

Keyword(s):

Facial Expressions ◽

Social Communication ◽

Visual Information ◽

Mental States ◽

Form And Function ◽

Evolutionary Origins ◽

Functional Perspective ◽

Sensory Effects ◽

And Function ◽

Communicative Role

Facial expressions are an important source of social communication. But we do not know why they appear the way they do and how they arose. Here we discuss evidence supporting Darwin’s theory that our expressions originated for sensory egocentric function for the expresser, which were then co-opted as signals for allocentric social function. We show that facial expressions of fear and disgust have distinct opposing sensory effects that serve each emotion’s theorized function, regulating the intake of nasal and visual information. Then, we show how such egocentrically adaptive expressive forms may have been socially co-opted for allocentric function, transmitting basic gaze signals and complex mental states adaptively congruent for the receiver as the expresser. Together, the evidence connects the appearance of our expressions from their evolutionary origins to their modern-day communicative role, providing a functional perspective for organizing and understanding expression forms.

Download Full-text

Ambient illumination switches contrast preference of specific retinal processing streams

Journal of Neurophysiology ◽

10.1152/jn.00360.2015 ◽

2015 ◽

Vol 114 (1) ◽

pp. 540-550 ◽

Cited By ~ 18

Author(s):

James T. Pearson ◽

Daniel Kerschensteiner

Keyword(s):

Visual Information ◽

Large Scale ◽

Receptive Fields ◽

Direction Selectivity ◽

Dependent Manner ◽

Ambient Illumination ◽

Lighting Conditions ◽

Light Levels ◽

On And Off Pathways ◽

Spatiotemporal Receptive Fields

Contrast, a fundamental feature of visual scenes, is encoded in a distributed manner by ∼20 retinal ganglion cell (RGC) types, which stream visual information to the brain. RGC types respond preferentially to positive (ONpref) or negative (OFFpref) contrast and differ in their sensitivity to preferred contrast and responsiveness to nonpreferred stimuli. Vision operates over an enormous range of mean light levels. The influence of ambient illumination on contrast encoding across RGC types is not well understood. Here, we used large-scale multielectrode array recordings to characterize responses of mouse RGCs under lighting conditions spanning five orders in brightness magnitude. We identify three functional RGC types that switch contrast preference in a luminance-dependent manner (Sw1-, Sw2-, and Sw3-RGCs). As ambient illumination increases, Sw1- and Sw2-RGCs shift from ONpref to OFFpref and Sw3-RGCs from OFFpref to ONpref. In all cases, transitions in contrast preference are reversible and track light levels. By mapping spatiotemporal receptive fields at different mean light levels, we find that changes in input from ON and OFF pathways in receptive field centers underlie shifts in contrast preference. Sw2-RGCs exhibit direction-selective responses to motion stimuli. Despite changing contrast preference, direction selectivity of Sw2-RGCs and other RGCs as well as orientation-selective responses of RGCs remain stable across light levels.

Download Full-text

The Development of Form and Function in Fishes and the Question of Larval Adaptation

The Development of Form and Function in Fishes and the Question of Larval Adaptation ◽

10.47886/9781888569582.ch7 ◽

2004 ◽

Keyword(s):

Life History ◽

Visual Information ◽

Fish Larvae ◽

Bright Light ◽

Developmental Rate ◽

Motion Sensitivity ◽

Vertebrate Retina ◽

Form And Function ◽

Teleost Retina ◽

And Function

<em>Abstract.</em>—Although the basic structure of the vertebrate retina is similar across taxa, high variability in specific features of the fish retina reflects the differences in visual microhabitat of these species. The vertebrate retina is the first step in the neural integration of visual information. A great deal of retinal function can be inferred from structure, and as these relationships continue to be revealed, we are gaining new insights into how vision is integrated by the nervous system. Among fishes, the developmental rate and acquisition of retinal structures is highly variable. While some species develop all structures early in embryogenesis, others delay acquisition of the full adult retinal complement of cells until months after hatching. Given the tight relationship between structure and function, differences in the timing of retinogenesis have implications for the visionbased survival skills of the early life history stages and for the overall ecology and fitness of the species. Although much of the observed variation may be related to altricial versus precocial life history strategies, we suggest that protracted retinal development also reflects and separates the constraints imposed by the requirements of foraging and predator avoidance. As evidenced by a typically monochromatic all-cone retina, the eye of early fish larvae is adapted for efficient foraging in bright light. At later stages, an improved ability to identify the presence of predators is acquired via addition of rod photoreceptors for low light vision, as well as multiple cone spectral channels (and regularly geometric cone mosaics) for increased contrast and motion sensitivity. The larval retina of some species exhibits further specializations, such as the pure rod retina of the eel leptocephalus and the pure green cone retina of many marine teleosts. Overall, variation in the development of the teleost retina can be viewed as a continuum from very rapid to greatly delayed. The developmental trajectory of the visual system in any given species represents a product of evolutionary history, developmental constraints, and foraging and predation pressures.

Download Full-text

The effects of the NMDAR co-agonist D-serine on the structure and function of the optic tectum

10.1101/2021.08.25.457610 ◽

2021 ◽

Author(s):

Zahraa Chorghay ◽

Vanessa J. Li ◽

Arna Ghosh ◽

Anne Schohl ◽

Edward S. Ruthazer

Keyword(s):

Optic Tectum ◽

Receptive Fields ◽

Chronic Administration ◽

Dendritic Morphology ◽

Glutamatergic Synapses ◽

Functional Changes ◽

Synapse Density ◽

Mature Neurons ◽

Tectal Neurons ◽

And Function

The N-methyl-D-aspartate type glutamate receptor (NMDAR) is a molecular coincidence detector which converts correlated patterns of neuronal activity into cues for the structural and functional refinement of developing circuits in the brain. D-serine is an endogenous co-agonist of the NMDAR. In this study, we investigated the effects of potent enhancement of NMDAR-mediated currents by chronic administration of saturating levels of D-serine on the developing Xenopus retinotectal circuit. Chronic exposure to the NMDAR co-agonist D-serine resulted in structural and functional changes to the optic tectum. D-serine administration affected synaptogenesis and dendritic morphology in recently differentiated tectal neurons, resulting in increased arbor compaction, reduced branch dynamics, and higher synapse density. These effects were not observed in more mature neurons. Calcium imaging to examine retinotopic map organization revealed that tectal neurons of animals raised in D-serine had sharper visual receptive fields . These findings suggest that the availability of endogenous NMDAR co-agonists like D-serine at glutamatergic synapses may regulate the refinement of circuits in the developing brain.

Download Full-text

Ultrastructure of developing visual cortical synapses in the cat superior colliculus

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100085083 ◽

1991 ◽

Vol 49 ◽

pp. 156-157

Author(s):

Caroline A. Miller ◽

Laura L. Bruce

Keyword(s):

Superior Colliculus ◽

Phosphate Buffer ◽

Receptive Fields ◽

Visual Cortical Area ◽

Cortical Synapses ◽

Visual Cortical ◽

And Function ◽

Phosphate Buffered Saline ◽

The Brain ◽

Cat Superior Colliculus

The first visual cortical axons arrive in the cat superior colliculus by the time of birth. Adultlike receptive fields develop slowly over several weeks following birth. The developing cortical axons go through a sequence of changes before acquiring their adultlike morphology and function. To determine how these axons interact with neurons in the colliculus, cortico-collicular axons were labeled with biocytin (an anterograde neuronal tracer) and studied with electron microscopy.Deeply anesthetized animals received 200-500 nl injections of biocytin (Sigma; 5% in phosphate buffer) in the lateral suprasylvian visual cortical area. After a 24 hr survival time, the animals were deeply anesthetized and perfused with 0.9% phosphate buffered saline followed by fixation with a solution of 1.25% glutaraldehyde and 1.0% paraformaldehyde in 0.1M phosphate buffer. The brain was sectioned transversely on a vibratome at 50 μm. The tissue was processed immediately to visualize the biocytin.

Download Full-text

Scanning tunneling microscopy (STM) of DNA and RNA

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100152148 ◽

1989 ◽

Vol 47 ◽

pp. 34-35

Author(s):

Patricia G. Arscott ◽

Gil Lee ◽

Victor A. Bloomfield ◽

D. Fennell Evans

Keyword(s):

Molecular Structures ◽

Inorganic Materials ◽

Resolving Power ◽

Scanning Tunneling ◽

Tunneling Microscopy ◽

Form And Function ◽

Dna And Rna ◽

Calf Thymus ◽

And Function ◽

The Relationship

STM is one of the most promising techniques available for visualizing the fine details of biomolecular structure. It has been used to map the surface topography of inorganic materials in atomic dimensions, and thus has the resolving power not only to determine the conformation of small molecules but to distinguish site-specific features within a molecule. That level of detail is of critical importance in understanding the relationship between form and function in biological systems. The size, shape, and accessibility of molecular structures can be determined much more accurately by STM than by electron microscopy since no staining, shadowing or labeling with heavy metals is required, and there is no exposure to damaging radiation by electrons. Crystallography and most other physical techniques do not give information about individual molecules.We have obtained striking images of DNA and RNA, using calf thymus DNA and two synthetic polynucleotides, poly(dG-me5dC)·poly(dG-me5dC) and poly(rA)·poly(rU).

Download Full-text