Sensory representations are dynamically maintained by ascending and descending connections linking the cerebral cortex and the thalamus. Although the overall extent and topographic specificity of descending corticothalamic projections can equal or surpass that of thalamocortical projections, little is known about their role in perception or learning. Here, we propose a new chemical-genetic approach known as DREADDs (Designer Receptors Exclusively Activated by Designer Drugs) to parse the functional contribution of corticothalamic circuits that arise from layer 5 versus layer 6 of primay and secondary areas of the auditory cortex. By silencing specific cortical feedback circuits while recording from ensembles of thalamic neurons in mice that are either passively listening to sound or are actively engaged in listening tasks, we will gain deeper insight into the workings of multiple, parallel feedback systems that enable the cerebral cortex to modify its afferent input stream.

Public Health Relevance

On a technical level, these studies will characterize a new approach to remotely silence particular cell types in the brain. This could lead to new, less invasive therapies for neurological disorders characterized by pathological activity levels such as Parkinson's disease, Epileptic Seizure, and Tinnitus. On a conceptual level, these findings could influence the next generation of smart medical technologies that seek to reduce bottom-up data bottlenecks by self-selecting only the information needed to form more valuable predictive models.

Agency
National Institute of Health (NIH)
Institute
National Institute on Deafness and Other Communication Disorders (NIDCD)
Type
Exploratory/Developmental Grants (R21)
Project #
5R21DC012894-02
Application #
8610288
Study Section
Auditory System Study Section (AUD)
Program Officer
Platt, Christopher
Project Start
2013-02-01
Project End
2015-01-31
Budget Start
2014-02-01
Budget End
2015-01-31
Support Year
2
Fiscal Year
2014
Total Cost
$184,500
Indirect Cost
$72,000
Name
Massachusetts Eye and Ear Infirmary
Department
Type
DUNS #
073825945
City
Boston
State
MA
Country
United States
Zip Code
02114
Schreiner, Christoph E; Polley, Daniel B (2014) Auditory map plasticity: diversity in causes and consequences. Curr Opin Neurobiol 24:143-56