Posts classified under: Neuroendocrinology and Sex Differences

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, 9 graduate students, and 8 postdoctoral scholars, and has served in university faculty governance as well as led 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 has served as 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 over 1000 PhD level alumni.

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

Cao J, Herman AB, West GB, Poe G, Savage VM. Unraveling why we sleep: Quantitative analysis reveals abrupt transition from neural reorganization to repair in early development. Sci Adv 6(38):eaba0398 (11 pages), 2020. doi: 10.1126/sciadv.aba0398.

Guthrie R, Ciliberti D, Mankin E, Poe GR. Recurrent hippocampo-neocortical sleep-state divergence in humans. PNAS 119(44): e2123427119, PM36279474, 2022.

Frazer M, Cabrera Y, Guthrie R, Poe GR. Shining a light on the mechanisms of sleep for memory consolidation. Current Sleep Medicine Rep, 7:221-231, 2021.

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

Daniel Silverman, M.D., Ph.D.


Daniel H. Silverman, M.D., Ph.D., is Head of the Neuronuclear Imaging Section of the Ahmanson Translational Imaging Division at UCLA Medical Center, on the Executive Committee of the UCLA Alzheimer’s Disease Research Center, and a Professor in the Department of Molecular and Medical Pharmacology, University of California, Los Angeles. He obtained his Ph.D. in Biological Chemistry at Harvard University, and postdoctoral research training in Biochemistry and Molecular Pharmacology at Harvard Medical School. He obtained his M.D. from The Ohio State University College of Medicine, subsequently completed post-M.D. training at UCLA, and then obtained certification from both the American Board of Internal Medicine and the American Board of Nuclear Medicine.

Niranjala Tillakaratne, Ph.D


A selected list of publications:

Duru Paul, Tillakaratne Niranjala, Kim Jung, Zhong Hui, Stauber Stacey, Pham Tran, Xiao Mei Si, Edgerton V. Reggie, Roy Roland.   Spinal neuronal activation during locomotor-like activity enabled by epidural stimulation and 5-hydroxytryptamine agonists in spinal rats, J Neurosci Res, 2015; 93(8): 1229-1239.
Tillakaratne Niranjala J K, Duru Paul, Fujino Hidemi, Zhong Hui, Xiao Mei Si, Edgerton V Reggie, Roy Roland R   Identification of interneurons activated at different inclines during treadmill locomotion in adult rats Journal of neuroscience research, 2014; 92(12): 1714-22.
Shah Prithvi K, Garcia-Alias Guillermo, Choe Jaehoon, Gad Parag, Gerasimenko Yury, Tillakaratne Niranjala, Zhong Hui, Roy Roland R, Edgerton V Reggie   Use of quadrupedal step training to re-engage spinal interneuronal networks and improve locomotor function after spinal cord injury Brain : a journal of neurology, 2013; 136(Pt 11): 3362-77.
Joseph M Selvan, Ying Zhe, Zhuang Yumei, Zhong Hui, Wu Aiguo, Bhatia Harsharan S, Cruz Rusvelda, Tillakaratne Niranjala J K, Roy Roland R, Edgerton V Reggie, Gomez-Pinilla Fernando   Effects of diet and/or exercise in enhancing spinal cord sensorimotor learning PloS one, 2012; 7(7): e41288.
Joseph M Selvan, Bilousova Tina, Zdunowski Sharon, Wu Zhongqi-Phyllis, Middleton Blake, Boudzinskaia Maia, Wong Bonnie, Ali Noore, Zhong Hui, Yong Jing, Washburn Lorraine, Escande-Beillard Nathalie, Dang Hoa, Edgerton V Reggie, Tillakaratne Niranjala J K, Kaufman Daniel L   Transgenic mice with enhanced neuronal major histocompatibility complex class I expression recover locomotor function better after spinal cord injury Journal of neuroscience research, 2011; 89(3): 365-72.
Tillakaratne NJ, Guu JJ, de Leon RD, Bigbee AJ, London NJ, Zhong H, Ziegler M,Joynes R, Roy RR, Edgerton VR.   Functional recovery of stepping in rats after a complete neonatal spinal cord transection is not due to regrowth across the lesion site , Neuroscience, 2010; 166: 23-33.
Khristy W, Ali NJ, Bravo AB, de Leon R, Roy RR, Zhong H, London NJ, Edgerton VR, Tillakaratne NJ   Changes in GABA(A) receptor subunit gamma 2 in extensor and flexor motoneurons and astrocytes after spinal cord transection and motor training, Brain Res, 2009; 1273: 9-17.
Otoshi CK, Walwyn WM, Tillakaratne NJ, Zhong H, Roy RR, Edgerton VR   Distribution and localization of 5-HT(1A) receptors in the rat lumbar spinal cord after transection and deafferentation, J Neurotrauma, 2009; 26: 575-84.
Jindrich DL, Joseph MS, Otoshi CK, Wei RY, Zhong H, Roy RR, Tillakaratne NJ,Edgerton VR   Spinal learning in the adult mouse using the Horridge paradigm, J Neurosci Methods, , 2009; 182(2): 250-4.
Edgerton VR, Courtine G, Gerasimenko YP, Lavrov I, Ichiyama RM, Fong AJ, Cai LL, Otoshi CK, Tillakaratne NJ, Burdick JW, Roy RR   Training locomotor networks, Brain Res Rev, 2008; 57: 241-54 (Review).
Bigbee AJ, Crown ED, Ferguson AR, Roy RR, Tillakaratne NJ, Grau JW, Edgerton VR   Two chronic motor training paradigms differentially influence acute, Behav Brain Res, 2007; 180: 95-101.
Ahn, SN Guu, JJ Tobin, AJ Edgerton, VR Tillakaratne, NJ   Use of c-fos to identify activity-dependent spinal neurons after stepping in intact adult rats Spinal Cord, 2006; 44: 547-59.
Zanjani H, Lemaigre-Dubreuil Y, Tillakaratne NJK, Blokhin A, McMahon RP, Tobin AJ and Vogel MW.   Cerebellar Purkinje cell loss in aging Hu-Bcl2 transgenic mice, J Comp Neurol, 2004; 475: 481-92.
Edgerton VR, Tillakaratne NJK, Bigbee AJ, de Leon RD, and Roy RR   Locomotor recovery potential after spinal cord injury, Neuro-behavioral determinants of interlimb coordination, edited by Swinnen S. & P Duysens J, 2004; .
Edgerton, VR Tillakaratne, NJ Bigbee, AJ de Leon, RD Roy, RR   Plasticity of the spinal neural circuitry after injury Annual review of neuroscience. , 2004; 27: 145-67.
Hoang, TX Nieto, JH Tillakaratne, NJ Havton, LA   Autonomic and motor neuron death is progressive and parallel in a lumbosacral ventral root avulsion model of cauda equina injury The Journal of comparative neurology. , 2003; 467(4): 477-86.
Mackie, M Hughes, DI Maxwell, DJ Tillakaratne, NJ Todd, AJ   Distribution and colocalisation of glutamate decarboxylase isoforms in the rat spinal cord Neuroscience. , 2003; 119(2): 461-72.
Tillakaratne, NJ de Leon, RD Hoang, TX Roy, RR Edgerton, VR Tobin, AJ   Use-dependent modulation of inhibitory capacity in the feline lumbar spinal cord The Journal of neuroscience, 2002; 22(8): 3130-43.
Edgerton, VR Leon, RD Harkema, SJ Hodgson, JA London, N Reinkensmeyer, DJ Roy, RR Talmadge, RJ Tillakaratne, NJ Timoszyk, W Tobin, A   Retraining the injured spinal cord The Journal of physiology. , 2001; 533(Pt 1): 15-22.
Tillakaratne, NJ Mouria, M Ziv, NB Roy, RR Edgerton, VR Tobin, AJ   Increased expression of glutamate decarboxylase (GAD(67)) in feline lumbar spinal cord after complete thoracic spinal cord transection Journal of neuroscience research. , 2000; 60(2): 219-30.
Banerjee, PK Tillakaratne, NJ Brailowsky, S Olsen, RW Tobin, AJ Snead, OC   Alterations in GABAA receptor alpha 1 and alpha 4 subunit mRNA levels in thalamic relay nuclei following absence-like seizures in rats Experimental neurology. , 1998; 154(1): 213-23.
Banerjee PK, Olsen RW, Tillakaratne NJK, Brailowsky S, Tobin AJ, and Snead OC, 3rd.   Absence seizures decrease steroid modulation of t-[35S]butylbicyclophosphorothionate binding in thalamic relay nuclei, J Pharmacol Exp Ther, 1998; 287: 766-772.
Edgerton VR, Roy RR, de Leon RD, Tillakaratne NJK, and Hodgson JA.   Does motor learning occur in spinal cord?, The neuroscientist, 1997; 3: 287-294.
Edgerton, VR de Leon, RD Tillakaratne, N Recktenwald, MR Hodgson, JA Roy, RR   Use-dependent plasticity in spinal stepping and standing Advances in neurology. , 1997; 72: 233-47.
Mahmoudi M, Kang M H, Tillakaratne N, Tobin A J, Olsen R W   Chronic intermittent ethanol treatment in rats increases GABA(A) receptor alpha4-subunit expression: possible relevance to alcohol dependence Journal of neurochemistry, 1997; 68(6): 2485-92.
Tillakaratne N J, Medina-Kauwe L, Gibson K M   gamma-Aminobutyric acid (GABA) metabolism in mammalian neural and nonneural tissues Comparative biochemistry and physiology. Part A, Physiology, 1995; 112(2): 247-63.
Segovia J, Lawless G M, Tillakaratne N J, Brenner M, Tobin A J   Cyclic AMP decreases the expression of a neuronal marker (GAD67) and increases the expression of an astroglial marker (GFAP) in C6 cells Journal of neurochemistry, 1994; 63(4): 1218-25.
Hendrickson A E, Tillakaratne N J, Mehra R D, Esclapez M, Erickson A, Vician L, Tobin A J   Differential localization of two glutamic acid decarboxylases (GAD65 and GAD67) in adult monkey visual cortex The Journal of comparative neurology, 1994; 343(4): 566-81.
Medina-Kauwe L K, Tillakaratne N J, Wu J Y, Tobin A J   A rat brain cDNA encodes enzymatically active GABA transaminase and provides a molecular probe for GABA-catabolizing cells Journal of neurochemistry, 1994; 62(4): 1267-75.
Esclapez M, Tillakaratne N J, Kaufman D L, Tobin A J, Houser C R   Comparative localization of two forms of glutamic acid decarboxylase and their mRNAs in rat brain supports the concept of functional differences between the forms The Journal of neuroscience : the official journal of the Society for Neuroscience, 1994; 14(3 Pt 2): 1834-55.
Esclapez M, Tillakaratne N J, Tobin A J, Houser C R   Comparative localization of mRNAs encoding two forms of glutamic acid decarboxylase with nonradioactive in situ hybridization methods The Journal of comparative neurology, 1993; 331(3): 339-62.
Greif K F, Tillakaratne N J, Erlander M G, Feldblum S, Tobin A J   Transient increase in expression of a glutamate decarboxylase (GAD) mRNA during the postnatal development of the rat striatum Developmental biology, 1992; 153(1): 158-64.
Kasckow J W, Tillakaratne N J, Kim H, Strecker G J, Tobin A J, Olsen R W   Expression of GABAA receptor polypeptides in clonal rat cell lines Brain research, 1992; 581(1): 143-7.
Bu D F, Erlander M G, Hitz B C, Tillakaratne N J, Kaufman D L, Wagner-McPherson C B, Evans G A, Tobin A J   Two human glutamate decarboxylases, 65-kDa GAD and 67-kDa GAD, are each encoded by a single gene Proceedings of the National Academy of Sciences of the United States of America, 1992; 89(6): 2115-9.
Tillakaratne N J, Erlander M G, Collard M W, Greif K F, Tobin A J   Glutamate decarboxylases in nonneural cells of rat testis and oviduct: differential expression of GAD65 and GAD67 Journal of neurochemistry, 1992; 58(2): 618-27.
Erlander M G, Tillakaratne N J, Feldblum S, Patel N, Tobin A J   Two genes encode distinct glutamate decarboxylases Neuron, 1991; 7(1): 91-100.
Khrestchatisky M, MacLennan A J, Tillakaratne N J, Chiang M Y, Tobin A J   Sequence and regional distribution of the mRNA encoding the alpha 2 polypeptide of rat gamma-aminobutyric acidA receptors Journal of neurochemistry, 1991; 56(5): 1717-22.
MacLennan A J, Brecha N, Khrestchatisky M, Sternini C, Tillakaratne N J, Chiang M Y, Anderson K, Lai M, Tobin A J   Independent cellular and ontogenetic expression of mRNAs encoding three alpha polypeptides of the rat GABAA receptor Neuroscience, 1991; 43(2-3): 369-80.
Greif K F, Erlander M G, Tillakaratne N J, Tobin A J   Postnatal expression of glutamate decarboxylases in developing rat cerebellum Neurochemical research, 1991; 16(3): 235-42.
Tobin A J, Khrestchatisky M, MacLennan A J, Chiang M Y, Tillakaratne N J, Xu W T, Jackson M B, Brecha N, Sternini C, Olsen R W   Structural, developmental and functional heterogeneity of rat GABAA receptors Advances in experimental medicine and biology, 1991; 287(3): 365-74.
John Maclennan A, Frantz G D, Weatherwax R C, Tillakaratne N J, Tobin A J   Expression of mRNAs that encode D2 dopamine receptor subtypes: Anatomical, developmental, and pharmacological studies Molecular and cellular neurosciences, 1990; 1(2): 151-60.
Segovia J, Tillakaratne N J, Whelan K, Tobin A J, Gale K   Parallel increases in striatal glutamic acid decarboxylase activity and mRNA levels in rats with lesions of the nigrostriatal pathway Brain research, 1990; 529(1-2): 345-8.
Kim Y S, Thomas J W, Tillakaratne N J, Montpied P, Suzdak P D, Banner C, Ginns E, Tobin A J, Paul S M   Glutamic acid decarboxylase mRNA in rat brain: regional distribution and effects of intrastriatal kainic acid Brain research, 1987; 427(1): 77-82.