Joshua Trachtenberg

Professor, Neurobiology, University of California Los Angeles

(310) 825-0873

503 NRB
CA NRB 503
Los Angeles, CA 90095

My lab is interested in understanding how our earliest sensory experiences pattern synaptic connections in the cortex and how this, in turn, shapes the function of neural circuitry. We explore this in the visual system, including primary visual cortex, higher visual cortical regions, superior colliculus, amygdala, and thalamus. Vision is the primary sense we use to evaluate social structures, individual faces, threats, and rewards. Our goal is to understand the molecular and cellular mechanisms by which early experiences instruct synpatic connectivity, network connectivity, and network function in cortical circuits. We also wish to understand how these experiential changes shape behavior. Our work employs sophisticated imaging and molecular techniques, including longitudinal multi-photon imaging of genetically encoded calcium indicators that are expressed in specific cell types, and single cell transcriptomics.

 

Affiliations

Member, Brain Research Institute, Cell & Developmental Biology GPB Home Area, Molecular, Cellular & Integrative Physiology GPB Home Area, Neuroengineering Training Program, Neuroscience GPB Home Area
 

Research Interests

The future aint what it used to be – Yogi Berra It is precisely because the future is unpredictable that the mammalian brain has evolved the capacity to acquire new information through sensory experiences, store this information as memories, and rapidly retrieve this information to modify behavior. But how do novel sensory experiences embed themselves in the fabric of the brain to form memories? This question drives the research in my laboratory, which examines the cellular and synaptic mechanisms of experience-dependent plasticity in the neocortex. Specifically, I am interested in understanding i) where experience-dependent plasticity is initiated in the cortical circuitry; ii) how experience regulates the growth or retraction of synapses; iii) whether plasticity is restricted to only a subset of synaptic connections; iv) what distinguishes “critical period” plasticity from adult plasticity; v) how synaptic plasticity is altered in the aging and diseased brain. Techniques: To address these qustions, I use: 2-photon laser scanning microscopy to repeatedly image neurons, synapses, and proteins in the living brain of mice over periods of weeks 2-photon microscopy to acutely image cellular responses to sensory stimuli using calcium imaging. Intrinsic signal optical imaging to non-invasively and repeatedly image stimulus-induced responses in populations of neurons in the intact, living brain. Microelectrodes to monitor changes in neuronal responses to visual stimuli before and after a plasticity paradigm and to determine the laminar position of these changes Using these techniques, I directly examine experience-dependent changes in structure and function in the same cortical region. Understanding how synapse formation and elimination is regulated by experience and their roles in learning and memory is critically important to developing rationally-based therapeutic approaches to diseases such as Alzheimer’s disease, and related dementias, in which cognitive impairment is strongly correlated with a loss of synapses in the cortex.

Publications