PROJECTS

1. Neuromodulation in the Auditory Cortex

Personnel:
Humberto Salgado, Justin Nichols, Raj Byrapureddy, Laura Martinolich, Mitali Bose, Lu Dinh, Brian Roof, Amulya Ydlapalli, Neha Gandhi

The auditory cortex receives a strong cholinergic projection whose repeated activation induces long-lasting physiological changes. Aims of this project are:

a) identify and describe short-term effects of acetylcholine at glutamatergic and GABAergic synapses (TB, HS, JN, NG)
b) identify the effect of cholinergic agonists on the firing pattern of glutamatergic and GABAergic cells in the auditory cortex (RB)
c) study and identification of the dendritic and axonal morphology of the cells studied electrophysiologically (MB, BR, AY, CJ, AL)
d) localization of cholinergic receptors and cellular subtypes in the auditory cortex (LM, RB)
e) effect of monoamines in the modulation of cell and synaptic properties (HS)
f) interaction between cholinergic and monoaminergic second-messenger cascades in the modulation of cellular and synaptic properties (HS, RB)

2.  Physiology of the Tectal Lateral Commissure

Personnel:
Justin Nichols, Ankur Patel, Mitali Bose

The inferior colliculus and the brainstem are a part of the auditory pathway important in the generation of the poorly understood audiogenic seizures. Recently, a new auditory brainstem nucleus with reciprocal connections with the inferior colliculus (Tectal Lateral Commissure, TLC), has been identified. Aim of the this project are:

a) characterize the firing pattern of the cellular types present in the TLC (JN, AP, MB)
b) identification of the potassium conductance present in TLC neurons (JN, AP, MB)

3.  Effects of Environmental Enrichment on Cell Physiology of the Auditory Cortex

Personnel:
Justin Nichols, Ankur Patel, Vikram Jakkamsetti (Kilgard's lab), Humberto Salgado

Environmental enrichment (EE), intended as the exposure of an animal to an environment with an unusually high number and quality of stimuli, has been shown to induce large anatomical rearrangements. Aims of this project are:

a) identify possible changes in glutamatergic synaptic transmission following EE (JN, LD, VJ)
b) identify possible changes in GABAergic synaptic transmission following EE (JN, LD, VJ)

4.  Chemically-Induced Deafness and Morphology of Cortical Cells

Personnel:
Mitali Bose, Rajasekhar Byrapureddy

Deafness is associated with a variety of physiological changes in the auditory cortex. Aim of the project are:

a) identification of morphological changes following the induction of deafness by using Golgi staining (MB, RB)
b) quantification of such changes by morphometric techniques (MB, CJ, AL)

5.  Modeling of Cortical Networks

Personnel:
Lu Dinh, Nikki Nguyen, Humberto Salgado, Justin Nichols, Rajasekhar Byrapureddy

We are developing a software for the simulation of small cortical networks. Aims of this project are:

a) developing a realistic model of single pyramidal cell (LD)
b) developing a realistic model of fast-spiking and regular-spiking GABAergic neurons (LD)
c) simulate short-term properties of cortical synaptic release (LD)
d) generate a model of electrically and synaptically coupled GABAergic neurons (LD, NN)
e) generate experimental data for optimizing the simulation parameters (HS, JN)
f) use the model for determining basic small cortical circuit properties (LD, NN, JN)

6.  Dopamine-Acetylcholine Interactions in the Hippocampus

Personnel:
Aurelien Begue, Humberto Salgado

We found that in the auditory cortex dopamine interacts with muscarinic agonists in the depression of neurotransmitter release. Aim of this project is:

a) identify a similar cross-talk in the hippocampus (AB, HS)
b) determine the possible effect of muscarinic and dopaminergic agonist and their interactions in longt-term plasticity (AB, HS)