Professor and Director, Department of Neuroscience; Co-Director, Brain Science Institute
Human behavior is a reflection of brain function. Our emotions, our intelligence, and our ability to learn and remember all depend on the complexity of connections between hundreds of billions of nerve cells in the human brain. These intricate connections form neuronal circuits that are constantly modified during life by experience. Neurons connect with each other at specialized areas, called synapses, where signals are sent and received between neurons. At synapses, active neurons release neurotransmitters that travel across the narrow gap between the neurons and bind to specific receptor molecules on the neighboring neuron.
Each of the billions of neurons in the human brain can have up to 10,000 synaptic connections. By establishing an ever-changing network of synapses, the brain is able to attain the level of functional complexity that underlies human behavior. The formation and withdrawal of synaptic connections between neurons is a dynamic process that can be modified by experience. In addition, experience can change the efficacy of existing synapses. This constant change in the synaptic communication between neurons is called synaptic plasticity and is critical for higher brain functions such as learning and memory. We are interested in the mechanisms that regulate synaptic transmission and synaptic plasticity. Our general approach is to study molecular and cellular mechanisms that regulate neurotransmitter receptors and synapse function.
Neurotransmitter receptors mediate the response of neurons to neurotransmitters released at synapses and are a central convergence point for transmission of signals between neurons. Modulation of the function of these receptors is a powerful and efficient way to modulate synaptic communication and synaptic plasticity. Studies from our laboratory and several other laboratories over the last 15 years have shown that the dynamic regulation of receptor function and expression at synapses mediates many forms of synaptic plasticity in the brain. We have recently focused on the mechanisms that underlie the regulation of glutamate receptors, the major excitatory neurotransmitter receptors in the brain. These receptors are neurotransmitter-dependent ion channels that allow ions to pass through the neuronal cell membrane, resulting in the excitation of the neuron. Glutamate receptors play critical roles in learning and memory, development of the brain, and neurological and psychiatric disorders.