Guest Editors
Didhiti Mukherjee
Johns Hopkins University
Dr. Didhiti Mukherjee received her PhD from the University of Iowa, Iowa City, USA, in 2018 and is currently working as a postdoctoral fellow at Johns Hopkins University, Baltimore, USA. Understanding how sensory experience shapes the development of sensory areas has been an overarching theme of her research. Her dissertation research in Prof. Mark Blumberg’s laboratory concerned the processing of self-generated movements in several brain structures critically important for motor behavior in developing rats during sleep and wakefulness. Using in vivo extracellular neurophysiology, histology, and behavioral techniques, she identified neural structures, pathways, and mechanisms that enable developing animals to make a fundamental distinction between “self”- and “other”-generated movements. Her postdoctoral research in Prof. Patrick Kanold’s laboratory pertains to understanding how spontaneous activity and early sensory experience from the periphery modulate the circuits and function of the developing auditory cortex using in vivo calcium imaging, in vivo and in vitro electrophysiological recording, and histological techniques. She demonstrated, for the first time, that early sound deprivation can profoundly alter activity in the developing auditory cortex earlier than the onset of the traditional “critical period.” Currently, she is investigating the impact of early peripheral experience on cross-modal cortical plasticity during development.
Minzi Chang
Johns Hopkins University
Dr. Minzi Chang is a postdoctoral fellow in Dr. Patrick Kanold's laboratory in the Department of Biomedical Engineering at Johns Hopkins University, USA. She obtained her PhD from Soka University, Japan, in 2019. Her graduate research focused on the architectural cortical development across different sensory modalities and how maternal thyroid hormone affects fetal cortical development in mice. She demonstrated cytoarchitectural differences in the auditory cortex compared to other sensory cortical areas based on laminar-specific gene expression. Being intrigued by the unique developmental pattern of the auditory cortex, she wanted to explore the auditory cortical circuit development further in-depth. In her postdoctoral research, she is currently investigating subplate neurons, one of the earliest born neurons in developing cortices. Her current project focuses on understanding the functional connection between the primary and higher-order auditory cortices and thalamus during postnatal development, before and after the ear canals are open in newborn mice. The techniques she is currently using to address her research questions include laser-scanning photo-stimulation, optogenetic manipulation, and two-photon imaging.
Collection Overview
The ability to distinguish, localize, and identify a myriad of sounds is due to neural processing originating in the ear, going through multiple subcortical areas, and continuing in the auditory cortex. These neural processes, however, are not hardwired in the brain. Instead, they develop in a protracted process that begins prenatally, continues through early postnatal days, and requires a complex interplay among gene expression, molecular guidance cues, spontaneous activity, and sensory experience from the periphery.
Consequently, any unanticipated changes along the auditory pathway during development could profoundly impact the normal processing of auditory stimuli. Therefore, it is critically important to understand how neurons in the auditory pathways assemble into a network during development to carry out its specific function. For example, the fact that roughly 1 in 20 people worldwide suffer from hearing impairment is one compelling reason to study the development of the auditory system, so that we may better understand and devise ways to prevent and treat hearing impairment.
This collection aims to highlight methods of studying auditory system development—from the periphery to the cortex—using animal models. These methods include but are not limited to (a) anatomical tracing, histology, in-utero electroporation to elucidate structural/circuit development in the auditory pathways, and (b) intracellular and extracellular neurophysiological recording, optical imaging, optogenetics, chemogenetics, gene expression studies, and behavioral assessments to examine functional changes in the developing auditory pathways. This will provide an overview of traditional and improvised methods used to determine how developing auditory pathways assemble into a network required for a functioning auditory system.
