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Principal Investigator: Tomomi Ichinose
Organization: WAYNE STATE UNIVERSITY
Fiscal Year: 2024
Award: $453,021
Funding agency: National Eye Institute
Abstract
Detection of moving objects is a retinal function which is crucial for an animal's survival. Multiple neurons and
neural networks in the retina have been identified as critical players in this task, including starburst amacrine
cells (SACs) and direction-selective ganglion cells (DSGCs), which sense direction of motion. Recent studies
have revealed that several neural networks among bipolar and amacrine cells are involved in direction
selectivity. However, the impact of environmental factors on motion sensitivity tuning of these neurons is not
well understood. Background scenery affects the gain control and tuning of neurons for object motion
detection; however, we have just begun to understand the sensitization and adaptation of those neurons. The
long-term objective of the present project is to understand the cellular and molecular mechanisms in the retina
for sensing direction of motion. We will conduct patch clamp recordings, two-photon calcium imaging,
immunohistochemistry, computational simulation, and behavioral studies to examine the mechanisms
underlying direction selectivity. We previously found that cholinergic feedback from SACs to bipolar cells
contributes to SAC direction selectivity. We now have evidence that the cholinergic feedback is transferred for
a long distance and tune SAC direction selectivity. Therefore, we hypothesize that an incoming object send a
signal to bipolar cells through a cholinergic pathway to tune SAC direction selectivity, a form of predictive
coding. We propose two Specific Aims to investigate long-distance cholinergic feedback. We will test this
hypothesis by recording long-distance cholinergic feedback in bipolar cells (Aim 1), and we will examine the
outcome of the long-distance cholinergic feedback in bipolar cell axon terminals, SAC dendrites, and DSGC
activity (Aim 2). Visual prediction is an essential feature for motion detection, which would reduce neural signal
delays and facilitate the animal reaction. Knowledge gained from the results of this project will shed light on the
additional layer of motion detection and visual signal processing in the retina.
Terms: <2-photon><Acceleration><Acetylcholine><Affect><Amacrine Cells><Animals><Axon Terminals><Body Tissues><Calcium><Cell Body><Cell Communication and Signaling><Cell Signaling><Cells><Code><Coding System><Computer Models><Computer Simulation><Computer based Simulation><Computerized Models><Dendrites><Detection><Diameter><Ecological impact><Environmental Factor><Environmental Impact><Environmental Risk Factor><Feedback><Image><Immunohistochemistry><Immunohistochemistry Cell/Tissue><Immunohistochemistry Staining Method><Intracellular Communication and Signaling><Knowledge><Light><Mediating><Mice><Mice Mammals><Molecular><Motion><Murine><Mus><Nerve Cells><Nerve Impulse Transmission><Nerve Transmission><Nerve Transmitter Substances><Nerve Unit><Neural Cell><Neural Retina><Neurocyte><Neuronal Transmission><Neurons><Neurotransmitters><Nicotinic Acetylcholine Receptors><Nicotinic Receptors><Outcome><Pathway interactions><Photoradiation><Presynaptic Nerve Endings><Presynaptic Terminals><Reaction><Reaction Time><Response RT><Response Time><Retina><Retina Proper><Signal Transduction><Signal Transduction Systems><Signaling><Speed><Stimulus><Synaptic Boutons><Synaptic Terminals><Testing><Tissues><Visual><axon signaling><axon-glial signaling><axonal signaling><behavior study><behavioral study><biological signal transduction><cholinergic><computational modeling><computational models><computational simulation><computer based models><computerized modeling><computerized simulation><environmental risk><gangliocyte><ganglion cell><glia signaling><glial signaling><imaging><meter><motion sensitivity><nerve signaling><neural network><neural signaling><neuronal><neuronal signaling><neurotransmission><object motion><patch clamp><pathway><psychomotor reaction time><receptive field><retinal neuron><signal processing><starburst amacrine><starburst amacrine cell><two-photon>