Descending feedback is a prominent feature of vertebrate sensory systems, yet its importance for neural information processing is not well understood. The objective of this proposal is to determine functional roles of feedback in sensory processing at the levels of cells, local circuits, and behavior. These studies will be carried out in the electrosensory lobe (ELL) of mormyrid electric fish. The ELL is a cerebellum-like structure that integrates incoming sensory signals from electroreceptors with feedback from higher stages in the electrosensory system.
Specific aim 1 will determine whether electrosensory feedback is used to generate predictions about the sensory environment.
Specific aim 2 will determine whether feedback is crucial for the detection of weak electrosensory signals.
Specific aim 3 will determine whether feedback controls spiketiming dependent synaptic plasticity in ELL. The proposed research will be conducted in vivo using intra- and extracellular recordings and behavioral measurements of electrosensory detection thresholds combined with inactivation of feedback. The results are expected to provide insights into how recurrent neural circuitry affects sensory processing.

Agency
National Institute of Health (NIH)
Institute
National Institute of Neurological Disorders and Stroke (NINDS)
Type
Postdoctoral Individual National Research Service Award (F32)
Project #
5F32NS049728-03
Application #
7109233
Study Section
Special Emphasis Panel (ZRG1-F02B (20))
Program Officer
Babcock, Debra J
Project Start
2004-09-01
Project End
2007-08-31
Budget Start
2006-09-01
Budget End
2007-08-31
Support Year
3
Fiscal Year
2006
Total Cost
$52,048
Indirect Cost
Name
Oregon Health and Science University
Department
Type
Schools of Medicine
DUNS #
096997515
City
Portland
State
OR
Country
United States
Zip Code
97239
Bell, Curtis C; Han, Victor; Sawtell, Nathaniel B (2008) Cerebellum-like structures and their implications for cerebellar function. Annu Rev Neurosci 31:1-24
Sawtell, Nathaniel B; Williams, Alan (2008) Transformations of electrosensory encoding associated with an adaptive filter. J Neurosci 28:1598-612
Sawtell, Nathaniel B; Williams, Alan; Bell, Curtis C (2007) Central control of dendritic spikes shapes the responses of Purkinje-like cells through spike timing-dependent synaptic plasticity. J Neurosci 27:1552-65
Sawtell, Nathaniel B; Williams, Alan; Roberts, Patrick D et al. (2006) Effects of sensing behavior on a latency code. J Neurosci 26:8221-34
Sawtell, Nathaniel B; Williams, Alan; Bell, Curtis C (2005) From sparks to spikes: information processing in the electrosensory systems of fish. Curr Opin Neurobiol 15:437-43