Posts classified under: Computational and Systems Neuroscience

Gina Poe, Ph.D.


Gina Poe has been working since 1995 on the mechanisms through which sleep serves memory consolidation and restructuring. Dr. Poe is a southern California native who graduated from Stanford University then worked for two post-baccalaureate years at the VA researching Air Force Test Pilots’ brainwave signatures under high-G maneuvers. She then earned her PhD in Basic Sleep in the Neuroscience Interdepartmental Program at UCLA under the guidance of Ronald Harper then moved to the University of Arizona for her postdoctoral studies with Carol Barnes and Bruce McNaughtons looking at graceful degradation of hippocampal function in aged rats as well as hippocampal coding in a 3-D maze navigated in the 1998 space shuttle mission. She brought these multiunit teachings to answer a burning question of whether REM sleep were for remembering or forgetting and found that activity of neurons during REM sleep is consistent both with the consolidation of novel memories and the elimination of already consolidated memories from the hippocampus, readying the associative memory network for new learning the next day. Moving first to Washington State University then to the University of Michigan before joining UCLA in 2016, Poe has over 80 undergraduates, 6 graduate students, and 6 postdoctoral scholars, and has served in university faculty governance as well as leading 5 different programs designed to diversify the neuroscience workforce and increase representation of people of the global majority in the STEM fields. At UCLA she continues research and teaching and Directs the COMPASS-Life Sciences and BRI-SURE programs and co-Directs the MARC-U*STAR program. Nationally she is course director of the Marine Biological Lab’s SPINES course and co-Directs the Society for Neuroscience’s NSP program which earned the nation’s highest mentoring honor in 2018. These programs have served over 600 PhD level trainees over the years.

Research Interests

The Poe lab investigates the mechanisms by which sleep traits serve learning and memory consolidation. Memories are encoded by the pattern of synaptic connections between neurons. We employ tetrode recording and optogenetic techniques in learning animals to see how neural patterns underlying learning are reactivated during sleep, and how activity during sleep influences the neural memory code. Both strengthening and weakening of synapses is important to the process of sculpting a network when we make new memories and integrate them into old schema. Results from our studies suggest that while synaptic strengthening can be efficiently accomplished during the waking learning process, the synaptic weakening part of memory integration requires conditions unique to sleep. The absence of noradrenaline during sleep spindles and REM sleep as well as the low levels of serotonin during REM sleep allow the brain to integrate new memories and to refresh and renew old synapses so that we are ready to build new associations the next waking period. Memory difficulties involved in post-traumatic stress disorder, Schizophrenia, Alzheimer’s disease and even autism involve abnormalities in the sleep-dependent memory consolidation process that my lab studies. Keywords: Sleep, learning and memory, PTSD, memory consolidation, reconsolidation, REM sleep, sleep spindles, Norepinephrine, LTP, depotentiation, reversal learning, optogenetics, electrophysiology, tetrode recordings, hippocampus, prefrontal cortex.


B.A., Human Biology, Stanford University 1987
Ph.D., Neuroscience, University of California, Los Angeles 1995

Selected Publications

Cabrera Y, Holloway J, Poe GR (2020) ‘Sleep Changes Across the Female Hormonal Cycle Affecting Memory: Implications for Resilient Adaptation to Traumatic Experiences.’ J Womens Health (Larchmt), 29 (3): 446-451. PMID: 32186966

Swift KM, Keus K, Echeverria CG, Cabrera Y, Jimenez J, Holloway J, Clawson BC, Poe GR () ‘Sex differences within sleep in gonadally-intact rats.’ Sleep, 2019.PMID: 31784755

Swift KM, Gross BA, Frazer MA, Bauer DS, Clark KJD, Vazey EM, Aston-Jones G, Li Y, Pickering AE, Sara SJ, Poe GR (2018) ‘Abnormal Locus Coeruleus Sleep Activity Alters Sleep Signatures of Memory Consolidation and Impairs Place Cell Stability and Spatial Memory.’ Curr Biol, 28 (22): 3599-3609.e4. PMID: 30393040

Zaborszky L, Gombkoto P, Varsanyi P, Poe GR, Role L, Ananth M, Rajebhosale P, Talmage D, Hasselmo M, Dannenberg H, Minces V, Chiba A, “Specific basal forebrain-cortical cholinergic circuits coordinate cognitive operations”, J Neurosci, 38 (44): 9446-9458 (2018).

Lewis P, Knoblich G, Poe GR, “Recasting reality: how memory replay in sleep boosts creative problem solving”, Trends Cogni Sci, 22 (6): 491-503 (2018).

Bjorness TE, Booth V, Poe GR (2018) ‘Hippocampal theta power pressure builds over non-REM sleep and dissipates within REM sleep episodes.’ Arch Ital Biol, 156 (3): 112-126. PMID: 30324607

Poe GR (2017) ‘Sleep Is for Forgetting.’ J Neurosci, 37 (3): 464-473. PMID: 28100731

Javanbakht, A and Poe, GR, “Behavioral neuroscience of circuits involved in arousal regulation”, The Neurobiology of PTSD, Ressler, K and Liberzon, I(Eds.), 130-147 (2016).

Emrick JJ, Gross BA, Riley BT, Poe GR (2016) ‘Different Simultaneous Sleep States in the Hippocampus and Neocortex.’ Sleep, 39 (12): 2201-2209. PMID: 27748240

Vanderheyden WM, George SA, Urpa L, Kehoe M, Liberzon I, Poe GR (2015) ‘Sleep alterations following exposure to stress predict fear-associated memory impairments in a rodent model of PTSD.’ Exp Brain Res, 233 (8): 2335-46. PMID: 26019008.

Watts A, Gritton HJ, Sweigart J, Poe GR (2012) ‘Antidepressant suppression of non-REM sleep spindles and REM sleep impairs hippocampus-dependent learning while augmenting striatum-dependent learning.’ J Neurosci, 32 (39): 13411-20. PMID: 23015432

Booth V, Poe GR (2006) ‘Input source and strength influences overall firing phase of model hippocampal CA1 pyramidal cells during theta: relevance to REM sleep reactivation and memory consolidation.’ Hippocampus, 16 (2): 161-73. PMID: 16411243

Ladan Shams, Ph.D.


A selected list of publications:

Watkins, S, Shams, L, Tanaka, S, et al.   Sound alters activity in human V1 in association with illusory visual perception, NeuroImage , 2006; .
Shams, L, Iwaki, S, Chawla, A, et al.   Early modulation of visual cortex by sound: an MEG study, Neuroscience letters, 2005; 378(2): 76-81.
Shams, L, Ma, WJ, & Beierholm, U.   Sound-induced flash illusion as an optimal percept, Neuroreport, , 2005; 16(17): 1923-7.
Violentyev, A, Shimojo, S, & Shams, L.   Touch-induced visual illusion, Neuroreport, 2005; 16(10): 1107-10.
Shams, L., & von der Malsburg, C.   Acquisition of visual shape primitives, Vision Research, 2002; Vol. 42 (17): 2105-2122.
Shams, L.   Integration in the brain: The subconscious alteration of visual perception by cross-modal integration, Science & Consciousness Review, 2002; October(No. 1 ): .
Bhattacharya, J., Shams, L., S. & Shimojo, S.   Sound-induced illusory flash perception: Role of Gamma band responses, NeuroReport, 2002; Vol. 13: 1727-1730.
Shams, L. & von der Malsburg, C.   The role of complex cells in object recognition, Vision Research, 2002; Vol. 42 (22): 2547-2554.
Shams, L., Kamitani, Y., & Shimojo, S.   Visual illusion induced by sound, Cognitive Brain Research, 2002; Vol. 14: 147-152.
Shams, L., Brady, M. & Schaal, S.   Graph-matching vs. entropy-based methods for object detection, Neural Networks, 2001; 14: 345-354.
Shimojo, S., & Shams, L.   Sensory modalities are not separate modalities: plasticity and interactions, Current Opinion In Neurobiology, 2001; Vol. 11 (114): 505-509.
Shams, L., Kamitani, Y., Thompson, S. & Shimojo, S.   Sound alters visual evoked potentials in humans, NeuroReport, 2001; Vol. 12 (17): 3849-3852.
Shimojo, S., Scheier, C., Shams, L., & Watanabe, K.   Vision beyond visual modality: Auditory effects on visual perception, Journal of the Acoustical Society of Japan, Special Issue on Hearing and the Brain, 2001; Vol. 22 (2): .
Shams, L., Kamitani, Y., & Shimojo, S.   What you see is what you hear, Nature, 2000; Vol. 408: 788.
Shams, L., & von der Malsburg, C.   Are Object Shape Primitives Learnable? , NeuroComputing, 1999; Vol. 26-27: 855-863.

Stan Schein, M.D., Ph.D.


A selected list of publications:

G Brinkmann, P Goetschalckx, S Schein   Comparing the constructions of Goldberg, Fuller, Caspar, Klug and Coxeter, and a general approach to local symmetry-preserving operations, Proc Roy Soc Lond A , 2017; 2017.0267.
S Schein, AJ Yeh, K Coolsaet, JM Gayed   Decoration of the truncated tetrahedron—an Archimedean polyhedron—to produce a new class of convex equilateral polyhedra with tetrahedral symmetry, Symmetry, 2016; 8: 82-91.
X Zhang, P Ge, X Yu, JM Brannan, G Bi, Q Zhang, S Schein, ZH Zhou   Cryo-EM structure of the mature dengue virus at 3.5-Å resolution, Nature Structural and Molecular Biology, 2012; 20: 105-110.
Wang Zhi, Su Hai-Feng, Tan Yuan-Zhi, Schein Stan, Lin Shui-Chao, Liu Wei, Wang Shu-Ao, Wang Wen-Guang, Tung Chen-Ho, Sun Di, Zheng Lan-Sun   Assembly of silver Trigons into a buckyball-like Ag180 nanocage Proceedings of the National Academy of Sciences of the United States of America, 2017; 114(46): 12132-12137.
Schein Stan, Gayed James Maurice   Fourth class of convex equilateral polyhedron with polyhedral symmetry related to fullerenes and viruses Proceedings of the National Academy of Sciences of the United States of America, 2014; 111(8): 2920-5.
Zhang Xiaokang, Ge Peng, Yu Xuekui, Brannan Jennifer M, Bi Guoqiang, Zhang Qinfen, Schein Stan, Zhou Z Hong   Cryo-EM structure of the mature dengue virus at 3.5-Å resolution Nature structural & molecular biology, 2013; 20(1): 105-10.
Schein S, Ngo IT, Huang TM, Klug K, Sterling P, Herr S   Cone synapses in macaque fovea: I. Two types of non-S cones are distinguished by numbers of contacts with OFF midget bipolar cells Vis Neurosci, 2011; 28(1): 3-16.
Hongrong Liu, Lei Jin, Sok Boon S. Koh, Ivo Atanasov, Stan Schein, Lily Wu, Z. Hong Zhou   Atomic Structure of Human Adenovirus by Cryo-EM Reveals Interactions Among Protein Networks Science, 2010; 329(5995): 1038-1043.
Zhang X, Boyce M, Bhattacharya B, Zhang X, Schein S, Roy P, Zhou ZH   Bluetongue virus coat protein VP2 contains sialic acid-binding domains, and VP5 resembles enveloped virus fusion proteins Proc Natl Acad Sci U S A, 2010; 107(14): 6292-7.
Ge P, Tsao J, Schein S, Green TJ, Luo M, Zhou ZH   Cryo-EM model of the bullet-shaped vesicular stomatitis virus Science, 2010; 327(5966): 689-93.
Schein Stan, Friedrich Tara   A geometric constraint, the head-to-tail exclusion rule, may be the basis for the isolated-pentagon rule in fullerenes with more than 60 vertices Proceedings of the National Academy of Sciences of the United States of America, 2008; 105(49): 19142-7.
Stan Schein, Michelle Sands-Kidner, Tara Friedrich   The physical basis for the head-to-tail rule that excludes most fullerene cages from self assembly Biophysical J, 2008; 94: 938-957.
Schein, S. Sands-Kidner, M.   A geometric principle may guide self-assembly of fullerene cages from clathrin triskelia and from carbon atoms Biophysical Journal, 2008; 94(3): 958-976.
S Schein, KM Ahmad   Efficiency of synaptic transmission of single-photoreceptor to rod bipolar dendrite, Biophysical J, 2006; 91: 3257-3267.
S Schein, KM Ahmad   A clockwork hypothesis: Synaptic release by rod photoreceptors must be regular, Biophysical J, 2005; 89: 3931-3949.
Schein, S. Sterling, P. Ngo, I. T. Huang, T. M. Herr, S.   Evidence that each S cone in macaque fovea drives one narrow-field and several wide-field blue-yellow ganglion cells Journal of Neuroscience, 2004; 24(38): 8366-8378.
Ahmad, K. M. Klug, K. Herr, S. Sterling, P. Schein, S.   Cell density ratios in a foveal patch in macaque retina Visual Neuroscience, 2003; 20(2): 189-209.
AA Sadun, V Carelli, SR Salomao, A Berezovsky, PA Quiros, F Sadun, AM DeNegri, R Andrade, M Moraes, A Passos, P Kjaer, J Pereira, ML Valentino, S Schein, R Belfort   Extensive investigation of a large Brazilian pedigree of 11778/Haplogroup J Leber American Journal of Ophthalmology, 2003; 136(2): 231-238.
S Herr, KJ Klug, P Sterling, S Schein   Inner S-cone bipolar cells provide all of the central elements for S cones in macaque retina, J Comp Neurol, 2003; 457: 185-201.
K Klug, S Herr, IT Ngo, P Sterling, S Schein   Macaque retina contains an S-cone OFF midget pathway, J Neurosci, 2003; 23: 9881-9887.
K Migdale, S Herr, K Klug, K Ahmad, K Linberg, P Sterling, S Schein   Two ribbon synaptic units in rod photoreceptors of macaque, human, and cat, J Comp Neurol, 2003; 455: 100-112.
Herr, S. Klug, K. Sterling, P. Schein, S.   Inner S-cone bipolar cells provide all of the central elements for S cones in macaque retina Journal of Comparative Neurology, 2003; 457(2): 185-201.
Burris, C. Klug, K. Ngo, I. T. Sterling, P. Schein, S.   How Muller glial cells in macaque fovea coat and isolate the synaptic terminals of cone photoreceptors Journal of Comparative Neurology, 2002; 453(1): 100-111.
AA Sadun, V Carelli, SR Salomao, A Berezovsky, P Quiros, F Sadun, AM DeNegri, R Andrade, S Schein, R Belfort   A very large Brazilian pedigree with 11 778 Leber’s hereditary optic, Trans Ant Ophthalmol Soc, 2002; 100: 169-77.
C Burris, K Klug, IT Ngo, P Sterling, S Schein   How Müller glial cells in macaque fovea coat and isolate the synaptic terminals of cone photoreceptors, J Comp Neurol, 2002; 453: 100-11.

Dario Ringach, Ph.D.


visual neurophysiology and perception

Our research focuses on visual perception and neurophysiology. In particular, we are interested in cortical dynamics, circuitry, function, and mathematical modeling of the visual system. The main methods in the laboratory include multi-electrode recordings from single neurons, as well as intrisic and voltage senstive dye imaging of visual cortex.

We also have an interest in developing novel technologies to record and stimulate from large neuronal populations for use in prostheses.