I am interested in the impact of psychoactive drugs on learning and memory, with a focus on the impact of addictive drugs on episodic memory accuracy and distortion.  In collaboration with Harriet de Wit, we have uncovered the impact of drugs such as amphetamine and THC (a primary psychoactive ingredient of cannabis) on different stages of memory (e.g., encoding, consolidation, retrieval), false memory creation, and emotional memory biases.

Memory Research Laboratory

Breathing emerges from coordinated interactions across multiple networks throughout the brain.  A difficulty in breathing is a common symptom of chronic drug use and in severe cases, a primary cause of mortality during overdose. My research uses cellular and animal models to understand how drugs and the brain environment interact to influence the control of breathing and other neurobiological processes.  Current work in the laboratory is focused on understanding how drug-induced changes in blood gases may influence the efficacy of drug action on the neural networks involved with breathing. Our work is focused on improving our mechanistic understanding into the influence of homeostatic context over drug efficacy in the brain.

Garcia Lab

My research is focused on the cell biology of ionotropic neurotransmitter receptors, the receptors responsible for the rapid postsynaptic response in nerve and muscle. These receptors are large oligomeric membrane proteins with subunits surrounding an ion channel that opens when neurotransmitters bind to the receptor. There are two different families of ionotropic neurotransmitter receptors. One family includes nicotinic acetylcholine receptors (AChRs), GABA and glycine receptors, and the other family covers the ionotropic glutamate receptors. There are several projects ongoing in my lab characterizing the assembly, trafficking and clustering of these receptors.

Department of Neurobiology

My chief expertise is in the development and use of advanced statistical methods for clustered and longitudinal data, with particular emphasis on mixed-effects models.  I have collaborated with smoking and nicotine researchers for many years.

Department of Public Health Sciences

My lab investigates the neurobiology and behavior of learned sequential movements, studying song learning and production in songbirds. A major component of the song system includes a pathway involving the basal ganglia and reinforcement learning.  In one line of research we are investigating intracellular (“intrinsic”) properties of song system neurons projecting to the basal ganlia that are directly tied to the individual bird’s singing behavior. One set of questions revolves around the role of dopamine and other transmitters in regulating network activity that helps set these properties.

Margoliash Lab

I investigate the cellular mechanisms underlying nicotine’s rewarding and antinociceptive effects. All drugs of abuse are known to enhance dopamine release from midbrain reward centers and this is a crucial step in the reinforcement of drug-taking behavior. I am specifically investigating the cellular mechanisms that contribute to this change in dopamine output. Most addictive drugs display significant analgesic profiles and our studies are also exploring the influence of nAChRs in pain control circuitry.

McGehee Lab

John Schneider MD, MPH is a network epidemiologist and interventionist who examines substance use disorder among most vulnerable populations including those with criminal justice involvement.  He focuses on the social and structural factors that create a context of substance use, mental health problems and infectious disease transmission like HIV and STIs.  He lead a NIDA analytic Center to develop advanced methods to better understand opioid overdose prevention among criminal justice involved populations with a particular interest in Black/African American community members.

Public Health Sciences

The capacity to acquire, store and recall knowledge of the world through experience and use this knowledge to maximize reward and avoid danger is essential for survival. In humans, this ability is fundamental to our sense of self and is in large part what makes us who we are. The brain’s memory systems are also vulnerable to disease and trauma, such as Alzheimer’s disease and post-traumatic stress disorder, and are also greatly impacted by addiction. 

My lab uses a combination of approaches to measure the activity of large populations of neurons, dendrites and axons in the hippocampus, which is known to be critical for memory function in both mice and humans, while mice experience virtual environments and are forming or recalling specific memories. We can also use light to control the activity of particular neurons or circuits, giving us a way to control the neural representations and circuits involved in memory.

Together, our aim is to reveal the features of neural function at the level of populations of neurons and brain-wide circuits down to the level of synapses, that allow for the formation and recall of specific memories, and in this way, we hope to provide insight into how these memory systems are altered during addiction and disease.

Department of Neurobiology