One of the basic questions in neuroscience is understanding how external stimuli are integrated with such dynamic internal states of the brain as fluctuating levels of anxiety. Deciphering the nature of these interactions and their effect on learning and memory is vital for understanding psychiatric disorders and complex cognition. In the Likhtik lab, we combine ideas from learning theory and neuroscience to study circuit-level mechanisms of learning, such as cortical-subcortical communication and the dialogue between excitatory and inhibitory neurons in different internal states. We focus our efforts on interactions between the amygdala, an important center for processing fear and safety information, with structures such as the basal forebrain and the prefrontal cortex. To probe circuit function we use multi-site recordings, optogenetics, pharmacology, anatomical and computational approaches that together highlight how neural communication is altered by anxiety. We study different kinds of learning (by using paradigms that include classical and operant conditioning, learned safety, extinction, fear generalization) as well as innate exploration of safe and aversive environments. Many of these paradigms model the behavior seen in human Anxiety Disorders such as Post Traumatic Stress Disorder (PTSD) and Generalized Anxiety Disorder (GAD).
- Cambiaghi M., Grosso A., Likhtik E., Mazziotti R., Concina G., Renna A., Sacco T., Gordon J.A., Sacchetti B. (2016) Higher order sensory cortex selectively drives basolateral amygdala activity during the recall of remote, but not recent, learned fearful memories. Journal of Neuroscience, 36(5):1647-1659.
- Likhtik E., Paz R. (2015) The amygdala and prefrontal cortex in (mal)adaptive learning. Trends in the Neurosciences, 38:158-166.
- Gore F., Schwartz E.C., Brangers B., C., Aladi S., Stujenske J.M., Likhtik E., Russo M.J., Gordon J.A., Salzman C.D., Axel R. (2015) Neural representations of unconditioned stimuli in basolateral amygdala mediate innate and learned responses. Cell, 162(1):134-145.
- Stujenske J.M., Likhtik E., Topiwala M.A., Gordon J.A. (2014) Fear and safety engage competing patterns of theta-gamma coupling in the basolateral amygdala. Neuron, 83(4):919-933.
- Likhtik E., Stujenske J.M., Topiwala M.A., Harris AZ Gordon J.A. (2014). Prefrontal entrainment of amygdala activity signals safety in learned fear and innate anxiety. Nature Neuroscience, 17(1):106-113.
- Likhtik E., Popa D., Apergis-Schoute J., Fidacaro G.A., Paré D. (2008) Amygdala intercalated neurons are required for expression of fear extinction. Nature, 454(7204):642-645.
- Likhtik E., Pelletier J.G., Paz R., Paré D. (2005) Prefrontal control of amygdala. Journal of Neuroscience, 25(32):7429-7437.
- Quirk G.J., Likhtik E., Pelletier J.G., Paré D. (2003) Stimulation of medial prefrontal cortex decreases the responsiveness of central amygdala output neurons. Journal of Neuroscience, 23(25):8800-7. Recommended by Faculty of 1000.