Our laboratory investigates the cellular and network mechanisms of cortical function using a variety of in vitro and in vivo approaches, from patch clamp recording in vivo, to voltage sensitive dye imaging and two photon microscopy in vitro. Recently, we have discovered that intracortical synaptic communication operates through both an analog and digital mode. We are currently investigating the mechanisms by which axons and synapses may operate in this regime.
Additional topics we are investigating are Recurrent Networks and their potential contribution to Gain Modulation, Working Memory, and Attention. In addition, we examine Visual Cortical receptive field mechanisms and fast plasticity. Finally, we also are investigating the mechanisms of cortical dynamics in the vibrissal and auditory systems of the awake animal. Together, our studies span from the sub-cellular, through the cellular and local network, all the way to the awake behaving animal in an effort to understand the cellular and network mechanisms of cortical function and dysfunction.
Extensive Research DescriptionFast Visual Cortical Plasticity: In the area of cortical function, we are investigating the mechanisms by which the cerebral cortex generates fast plastic changes in vision that allow for perceptual phenomenon, such as filling-in of blocked regions of visual space and adaptation to prolonged stimulation.
Persistent Activity in the Prefrontal Cortex: The prefrontal cortex generates persistent activity during periods of working memory, and this activity may be important for keeping ongoing tasks or facts in mind. We have developed an in vitro model of persistent activity in the prefrontal cortex and are currently investigating the network and cellular mechanisms for its generation.
Sleep-related Activity in the Cortex- implications for the operation of local cortical circuits: During sleep, the cerebral cortex generates spontaneous network activity. We are investigating the operation of the local cortical circuits in an in vitro model of this activity. These studies are helping us better understand the basic rules of local circuit operation in the cerebral cortex.
Thalamocortical Function and Modulation: The thalamus is a critical site for the control of information flow and processing in the forebrain. We continue to investigate the cellular and subcellular mechanisms by which the thalamus and cerebral cortex interact to generate normal and abnormal patterns of activity, as well as the precise mechanisms by which these structures are modulated by neuromodulatory neurotransmitters. Together these studies are yielding a unique understanding of visual system function and dysfunction and help to form a bridge between the molecular and cellular level all the way up to the cognitive neurosciences.
- Zagha E, Casale AE, Sachdev RN, McGinley MJ, McCormick DA. (2013) Motor cortex feedback influences sensory processing by modulating network state. Neuron 79(3):567-78.
- Tahvildari B, Wölfel M, Duque A, McCormick DA. Selective functional interactions between excitatory and inhibitory cortical neurons and differential contribution to persistent activity of the slow oscillation. J Neurosci. 2012 Aug 29;32(35):12165-79.
- Frohlich, F., McCormick, D.A. Endogenous electric fields may guide neocortical network activity. Neuron. 2010 Jul 15;67(1):129-43.
- Haider B, Krause MR, Duque A, Yu Y, Touryan J, Mazer JA, McCormick DA. Synaptic and network mechanisms of sparse and reliable visual cortical activity during nonclassical receptive field stimulation. Neuron. 2010 Jan 14;65(1):107-21.
- Haider, B. and McCormick D.A. (2009) Rapid neocortical dynamics: cellular and network mechanisms. Neuron 62: 171-189.
- Yu, Y., Shu, Y., McCormick D.A. (2008) Cortical action potential backpropagation explains spike threshold variability and rapid-onset kinetics. Journal of Neuroscience 28: 7260-7272.
- Hasenstaub, A., Sachdev, R.N.S., McCormick, D.A. (2007) State changes rapidly modulate cortical neuronal responsiveness. J. Neurosci. 27: 9607-9622.