Research interests

Our research has always focused on Visual Neuroscience. We are striving to seek a deep understanding of vision in the context of biology. Although the projects we have been working on are quite diverse, ranging from cellular physiology to animal behavior, the goal of our scientific pursuit is to integrate many facets of vision research into a coherent view of information processing and communication. By using multidisciplinary approaches, this endeavor has yielded significant results. Here we only describe the research works that were done in National Tsing Hua University in past few years. Other international collaboration works and previous works can be found in Publications.


Retinal neurobiology

Retina, ever since Cajal first characterized over one hundred years ago, has been the most extensive studied tissue on earth. Indeed, retina is the most approachable part of the brain, and it continues to provide us a wealth of knowledge about neural structure and processing. Mammalian retina is developmentally originated from the central nervous system, and the easy accessibility of the retina makes it a natural brain’s slice for addressing many important questions in neuroscience. The elegant neural network in the mammalian retina is accomplished by specific neurons and their synaptic connections. The overarching questions in our lab are (1) how visual information is processed in the intricate neural circuits of mammalian retinas, (2) how such specific neural circuits are formed developmentally, and (3) how the axons of retinal ganglion cells regenerate after injury. By using a variety of techniques, including electrophysiology, microinjection, gene-gunning, immunocytochemistry, electrical stimulation, etc., we have addressed all these questions. These include: (1) characterized the functional expression of AMPA and NMDA receptors on the morphologically identified RGCs of the rabbit retina, and found that RGCs with large somata may express various heterogeneous functional ionotropic glutamate receptors, thus in part rendering their functional diversity (Chen and Chiao, 2012), (2) mapped the spatial distribution pattern of the excitatory synapses on RGCs, and demonstrated how excitatory glutamatergic inputs shape neuronal responses (Chen and Chiao, 2014), (3) showed that the preferred directions of direction selective ganglion cells (DSGCs) at around the time of eye opening are not distinctly segregated but rather are diffusely distributed along the four canonical axes, which supports that the significant refinement after eye opening is required for the development of the four functional DSGC subtypes in the rabbit retina (Chan and Chiao, 2013), (4) examined the contribution and regulation of gap junctions to the development of the AII amacrine cell mediated rod pathway, and found that Cx36 expression in the AII-mediated rod pathway is activity dependent in the developing rabbit retina (Tu and Chiao, 2016), (5) studied the effects of electrical stimulation on neurite outgrowth of goldfish retinal explants, and showed that intermittent pulse is able to promote neurite regeneration most effectively, which provides a useful platform for investigating cellular mechanisms of CNS regeneration (Ou et al., 2012), and (6) studied the effects of increased neural activity on neurite outgrowth of mouse retinal explants, and showed that restoration of developmental neural activity can significantly facilitate axon growth of RGCs (Lee and Chiao, 2016). The ultimate goal of this research is to understand the general principles of visual information processing in the retinal circuitry and its underlying mechanisms of development and regeneration.


Cephalopod neuroethology

Cephalopods (octopus, squid, and cuttlefish) are a unique group of animals. Their visual system and brain organization are by far the most sophisticated among all invertebrates. On one hand, they can camouflage themselves against almost any background, a feat well appreciated by Aristotle, and one never mastered by any land animal. On the other hand, they can communicate with each other by changing body patterns dynamically, a talent that is akin to human sign language, one never exceeded by any aquatic vertebrate. Our studies and others in cephalopods have demonstrated that their ability to change skin coloration appropriately requires a sensorimotor system that can rapidly assess complex visual scenes and signals, and produce the motor output - the neutrally controlled adaptive body patterning - that achieves camouflage and communication (Chiao et al., 2015). Previous studies have also shown that the optic lobe is the motor command center for dynamic body patterning. However, little is known about its neural organization and the mechanisms underlying its control of body pattern generation. To gain further insight into neural processing of adaptive patterning for camouflage and communication in cephalopods, our lab has carefully examined the structure and function of the optic lobes in cuttlefish and squids (Liu and Chiao, 2017; Liu et al., 2017a,b,c). Moreover, to determine the functional significance of dynamic body patterning in visual communication, we have also characterized the spatiotemporal patterning of skin coloration during reproductive behaviors in oval squids (Lin et al., 2017). In addition to their unparalleled dynamic body patterning, cephalopods are well known for their intelligent behaviors. Previous studies have shown that almost all these cognitive behaviors require vision. However, it is largely unknown how cephalopods process visual information to determine the behavioral outcome. Our lab has developed several behavioral assays to study cuttlefish’s visual perception and cognition (Lee et al., 2012, 2013; Huang and Chiao, 2013; Yang and Chiao, 2016; Lin and Chiao, 2017). The ultimate goal of this research is to uncover the general principles of sensorimotor control for cephalopod’s dynamic body patterning and to reveal the neural basis of information processing in their visual behaviors.


Last updated July 20, 2018