Ernie Nordeen

Ernie Nordeen

Professor, Brain and Cognitive Sciences and Neurobiology and Anatomy

PhD, University of California at Irvine, 1982

Office Hours: By appointment

Research Overview

Throughout life, neural systems adapt in response to change. In fact, this neural flexibility is essential for maintaining behavioral stability. For instance, motor systems adapt when feedback from an animal's actions fails to produce the expected outcome. Neural signals reporting the disagreement between actual and expected feedback promote such adaptive behavioral change by prompting a functional re-mapping that can range from simple modifications in the gain of synaptic connections, to wholesale rewiring of well-mapped connections.

Our lab studies how adaptive plasticity occurs within a vocal motor system when feedback from an animal's vocalizations fails to match learned sensory-motor representations. In songbirds, as in humans, the stable production of learned vocalizations depends on normal auditory feedback. Altering or eliminating such feedback in adults produces gradual and long lasting changes in vocal performance. We study the neural processes that drive these feedback-based changes in vocal behavior, focusing on striatal-thalamic-cortical circuits that have been implicated in evaluating and adjusting learned motor behavior. The studies combine behavioral, neuroanatomical, and cellular analyses to identify brain regions and synaptic processes that promote adaptive changes in vocal motor behavior.

Research Interests

  • neurobiology of vocal learning and plasticity

Courses Taught

  • BCS 240:  Basic Neurobiology
  • BCS/NSC 249:  Developmental Neurobiology

Selected Publications

  • . Song tutoring triggers CaMKII phosphorylation within a specialized portion of the avian basal ganglia. J Neurobiol, 65(2): 179-191.
  • . Dissociation between extension of the sensitive period for avian vocal learning and the timing of dendritic spine loss in the lateral magnocellular nucleus of the anterior nidopallium. Neurobiol. Learning and Memory, 83: 143-150.
  • . Developmental patterns of NMDAR expression within the song system do not recur during adult vocal plasticity in zebra finches. J. Neurobiol, 58, 442-54.
  • . Synaptic and molecular mechanisms regulating plasticity during early learning. Ann. N.Y. Acad. Sci., 1016, 416-437.
  • . NR2B downregulation in a forebrain region required for avian vocal learning is not sufficient to close the sensitive period for song learning. Neurobiology of Learning and Memory, 79, 99-108.
  • . Seasonal regulation of NMDA receptor NR2B mRNA in the adult canary song system. J. Neurobiol., 54, 593-603.
  • . Developmental and hormonal regulation of NR2A mRNA in forebrain regions controlling avian vocal learning. Journal of Neurobiology, 51, 149-159.
  • . The relationship between rates of HVc neuron addition and vocal plasticity in adult songbirds. Journal of Neurobiology, 43, 79-88.
  • . Early sensory and hormonal experience modulate age-related changes in NR2B mRNA within a forebrain region controlling avian vocal learning. Journal of Neurobiology, 44, 82-94.
  • . Developmental regulation of NMDA receptor 2b subunit mRNA and ifenprodil binding in the zebra finch anterior forebrain. Journal of Neurobiology, 39, 155-167.
  • . Individual variation in neuron number predicts differences in the propensity for avian vocal imitation. Proceedings of the National Academy of Sciences, 95, 1277-1282.
  • . Anatomical and synaptic substrates for avian song learning. Journal of Neurobiology, 33, 532-548.
  • Aamodt, S.M., Nordeen, E.J., & Nordeen, K.W. (1996). Blockade of NMDA receptors during song model exposure impairs song development in juvenile Zebra finches. Learning and Memory, 65, 91-98.
  • . Blockade of NMDA receptors in the anterior forebrain impairs sensory acquisition in the Zebra finch. Neurobiology of Learning and Memory, 66, 295-304.
  • Aamodt, S.M., Nordeen, E.J., & Nordeen, K.W. (1995). Early isolation from conspecific song does not affect the normal developmental decline of NMDA receptor binding in an avian song nucleus. Journal of Neurobiology, 27, 76-84.
  • Nordeen, K.W., & Nordeen, E.J. (1992). Auditory feedback is necessary for the maintenance of stereotyped song in adult Zebra finches. Behavioral and Neural Biology, 57, 58-66.
  • Nordeen, E.J., & Nordeen, K.W. (1990). Neurogenesis and sensitive periods in avian vocal learning. Trends in Neurosciences, 13, 31-36.

Research Collaborators

Eliot A. Brenowitz, Professor, Depts Psychology and Biology, U. Washington

Kathy Nordeen, Professor, Dept Brain & Cognitive Sciences, U. 91×ÔÅÄÂÛ̳

Research Support

My research has been supported by grants from the National Institute of Mental Health, the National Science Foundation, the Sloan Foundation, and the Schmitt Program for Integrative Neuroscience.

Current Students & Research Associates

Aadavai Sridharan

Dr. David Holtzman

Former Graduate Students and Postdocs

Dr. Farida Sohrabji, Assoc. Professor, Texas A&M

Dr. Sandra Aamodt, Senior Editor, Nature Neuroscience

Dr. Michael Burek, Merck Pharmeceuticals

Dr. Mark Basham, Asst Professor, Metropolitan State College of Denver

Dr. Bonnie Ward, Post-doc, Wellesley College

Dr. Luisa Scott, Post-doc, U. of Texas, Austin

Dr. Julie Heinrich, Post-doc, U. Notre Dame

Marla Bruns (Master's student), MD/PhD program, Syracuse U.

Dr. Tryambak Singh (Postdoc), Assoc. Professor, Baranas Hindu U.