Our lab studies the neural mechanisms of memory in the everyday sense of the word: the ability to learn new facts and remember recent events. Although for many years scientists believed that only one form of learning existed in the brain, we now know that different brain networks are crucial for different types of learning. For example, the hippocampus is needed to learn and remember new facts and recent events, the amygdala is crucial for earning emotional associations, and the neostriatum is required for certain forms of skill learning. My research focuses on how the hippocampus, refrontal cortex, and other brain areas contribute to memory in experimental animals, mostly rats, and how mechanisms of neuronal plasticity within these structures contribute to memory functions. Experiments in my lab are guided by cognitive, computational, physiological, and pharmacological hypotheses.
The basic idea is that the properties of the NMDA receptor allows cells in the hippocampus to conjoin temporally overlapping cortical inputs into representations of events, and that recurrent connections within the hippocampus and between it and other structures allow these events to be linked into the sequences that comprise episodic memories. Interactions between the hippocampus and the prefrontal cortex allow specific memories to guide response rules, and different strategies and motives allow the prefrontal cortex to select among memories in otherwise identical situations. Experiments investigating the links between these different levels of analysis are aimed toward providing an integrated perspective of memory.
Fletcher, BR, Hill, GS, Long, JM, Gallagher, M, Shapiro, ML, Rapp, PR (2014) A fine balance: regulation of hippocampal Arc/Arg3.1 transcription, translation and degradation in a rat model of normal cognitive aging. Neurobiology of Learning and Memory, 115:58-67.
Seip-Cammack, KM & Shapiro, ML (2014). Behavioral flexibility and response selection are impaired after limited exposure to oxycodone. Learning and Memory, 21(12) 686-95.
Shapiro, M.L. (2014). Time and Again. Neuron 81:964-966.
Shapiro, M.L. (2013). Spatial navigation: head direction cells are anchored by gravity. Dispatch for Current Biology, 23(18):R841-R843.
Riceberg, J.S. & Shapiro, M.L. (2012). Reward stability determines the contribution of orbitofrontal cortex to adaptive behavior. Journal of Neuroscience, 14 November 2012, 32(46):16402-16409; doi:10.1523/JNEUROSCI.0776-12.2012.
Bahar, A.S. & Shapiro, M.L. (2012) Remembering to learn: Independent place and journey coding mechanisms contribute to memory transfer. Journal of Neuroscience, 32(6):2191-203.
Shapiro, ML (2011). Memory time. Neuron 71:571-573 (preview).
Young, JJ & Shapiro, ML (2011). Orbitofrontal cortex and response selection. Annals of the New York Academy of Sciences, 1239:25-32.
Bahar, AS, Shirvalkar, PR, & Shapiro, ML (2011). Memory guided learning: concurrent generalization and discrimination by CA1 and CA3 neuronal ensembles. Journal of Neuroscience, 31(34)12270-12281.
Ferbinteanu, J, Shirvalkar, PR, & Shapiro, ML (2011). Memory modulates journey-dependent coding in the hippocampus. Journal of
Young, JJ & Shapiro, ML (2011). Dynamic coding of goal-directed paths by orbital prefrontal cortex. Journal of Neuroscience
Shirvalkar P.R., & Shapiro M.L. (2010). Design and Construction of a Cost Effective Headstage for Simultaneous Neural Stimulation and Recording in the Water Maze. JoVE. http://www.jove.com/index/details.stp?id=2155, doi: 10.3791/2155
Shirvalkar, P. & Shapiro, M. L. (2010). Bidirectional modulation of hippocampal theta-gamma coherence regulates memory for recent spatial episodes. Proc. Natl. Acad. Sci. USA 107(15),7054-705.