Response of CA1 pyramidal neurons to frequency-modulated artificial synaptic inputs.

• Applicant: Dr. Tilman Broicher
• Subject Area: Molecular Biology and Physiology of Neurons and Glial Cells
• Term: from 2010 to 2012
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 193247695

During states of active exploration and attentiveness, prominent pseudo-periodic activity is observed in the hippocampus. This activity can be subdivided into two major frequency bands: the gamma band (30-80 Hz) oscillations and the much more prominent theta band (4-12 Hz) oscillations. These rhythms often appear nested, with gamma oscillations arising during a particular phase of the theta oscillation. Although implicated in a plethora of network functions, ranging from learning and memory to spatial navigation, the mechanism by which theta oscillations are generated, and whether intrinsic neuronal properties contribute to this phenomenon, remains unknown. Furthermore, the influence of theta oscillations on the activity of single neurons is still poorly understood. To investigate the impact of theta band modulated input on the basic pattern of action potential generation in CA1 pyramidal neurons, we intend to use dynamic clamp stimulation in vitro. Theta band oscillations will be generated by bombarding the neurons with trains of artificial synaptic inputs, which will be modulated in time. Preliminary data employing artificial synaptic input modulated at different frequencies indicates an input frequency dependence of action potential output in CA1 pyramidal neurons. The proposed project intends to continue this line of investigation by replicating different forms of oscillatory activity in the theta band and asking how manipulating the input, as well as certain intrinsic properties, affects the action potential output of CA1 pyramidal cells.

• DFG Programme: Research Fellowships
• International Connection: USA
• Host: Professor John A. White, Ph.D.