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Faculty Detail / 研究室詳細

Joshua P. Johansen, Ph.D.

- We study how aversive experiences trigger alterations in brain circuits and neural coding resulting in emotional memory formation.

Neural Circuitry of Memory

Team Leader

Experience dependent neural plasticity, Brain circuit mechanisms of learning and behavior

Joshua P. Johansen

Research Area

Our experiences in the world produce physical changes in the brain and as a result of these changes memories are formed. However, in our daily lives we are constantly barraged by sensory information, most of which we do not remember. What tells the brain to store some experiences as memories while others are forgotten? Answering this question is a central goal of our laboratory. Pleasurable and aversive experiences are powerful triggers for memory storage, telling our brain when an experience should be stored and remembered. To accomplish this task, aversive and pleasurable encounters activate neural ‘teaching signal’ circuits which can trigger brain alterations resulting in memory formation. Relative to our understanding of sensory and motor circuits, we understand very little about the brain circuits and mechanisms which translate aversive experiences into neural teaching signals. Though we are generally interested in the neural circuit mechanisms of associative learning and memory, our laboratory focuses on the study of teaching signals by examining the neural processes by which aversive experiences trigger behavioral fear conditioning. We study teaching signals using fear conditioning, a powerful model for studying behavioral memory formation. We take advantage of a multi-disciplinary approach, employing state of the art optogenetic techniques to causally manipulate teaching signal circuits and in-vivo electrophysiological methods to examine the computations performed by neurons in these circuits during behavioral learning. Our goals are to define the circuits that trigger aversive memory formation and elucidate the mechanisms by which aversive experiences trigger neural plasticity in memory storage areas. In addition, we aim to determine the computations performed by neurons in different parts of these circuits and establish how circuit processes give rise to these neural computations during behavioral learning and memory. Using this strategy we ultimately seek to discover general principles of neural circuit function, neural coding and plasticity as they relate to adaptive behavior.

Selected Publications View All

  1. 1

    Ozawa T, Ycu EA, Kumar A, Yeh L-F, Ahmed T, Koivumaa J, and Johansen JP: "A feedback neural circuit for calibrating aversive memory strength.", Nature Neuroscience", Nature Neuroscience, 20(1), 90-97 (2017)

  2. 2

    Uematsu A, Tan BZ, and Johansen JP: "Projection specificity in heterogeneous locus coeruleus cell populations: implications for learning and memory.", Learn Mem, 22(9), 444-51 (2016)

  3. 3

    Madarasz TJ, Diaz-Mataix L, Akhand O, Ycu EA, LeDoux JE, and Johansen JP: "Evaluation of ambiguous associations in the amygdala by learning the structure of the environment.", Nat Neurosci (2016)

  4. 4

    Herry C, and Johansen JP: "Encoding of fear learning and memory in distributed neuronal circuits.", Nat Neurosci, 17(12), 1644-1654 (2014)

  5. 5

    Johansen JP, Diaz-Mataix L, Hamanaka H, Ozawa T, Ycu E, Koivumaa J, Kumar A, Hou M, Deisseroth K, Boyden ES, and LeDoux JE: "Hebbian and neuromodulatory mechanisms interact to trigger associative memory formation.", Proc Natl Acad Sci U S A (2014)

  6. 6

    Johansen JP: "Neuroscience: Anxiety is the sum of its parts.", Nature (2013)

  7. 7

    Johansen JP, Wolff SB, Lüthi A, and Ledoux JE: "Controlling the Elements: An Optogenetic Approach to Understanding the Neural Circuits of Fear.", Biol Psychiatry, In press (2011)

  8. 8

    Johansen JP, Cain CK, Ostroff LE, and Ledoux JE: "Molecular mechanisms of fear learning and memory.", Cell, 147(3), 509-24 (2011)

  9. 9

    McNally GP, Johansen JP, and Blair HT: "Placing prediction into the fear circuit.", Trends Neurosci, 34(6), 283-92 (2011)

  10. 10

    Johansen JP, Tarpley JW, LeDoux JE, and Blair HT: "Neural substrates for expectation-modulated fear learning in the amygdala and periaqueductal gray.", Nat Neurosci, 13(8), 979-86 (2010)

  11. 11

    Johansen JP, Hamanaka H, Monfils MH, Behnia R, Deisseroth K, Blair HT, and LeDoux JE: "Optical activation of lateral amygdala pyramidal cells instructs associative fear learning.", Proc Natl Acad Sci U S A, 107(28), 12692-7 (2010)

  12. 12

    Schiller D, and Johansen JP: "Prelimbic prefrontal neurons drive fear expression: a clue for extinction--reconsolidation interactions.", J Neurosci., 29(43), 13432-4 (2009)

  13. 13

    Meng ID, Johansen JP, Harasawa I, and Fields HL: "Kappa opioids inhibit physiologically identified medullary pain modulating neurons and reduce morphine antinociception.", J Neurophysiol., 93(3), 1138-44 (2005)

  14. 14

    Johansen JP, and Fields HL: "Glutamatergic activation of anterior cingulate cortex produces an aversive teaching signal.", Nat Neurosci, 7(4), 398-403 (2004)

  15. 15

    Meng ID, and Johansen JP: "Antinociception and modulation of rostral ventromedial medulla neuronal activity by local microinfusion of a cannabinoid receptor agonist.", Neuroscience., 124(3), 685-93 (2004)

  16. 16

    Johansen JP, Fields HL, and Manning BH: "The affective component of pain in rodents: direct evidence for a contribution of the anterior cingulate cortex.", Proc Natl Acad Sci U S A., 98(14), 8077-82 (2001)

Press Releases View All