Student Resources | Faculty, Postdoc, & Staff Resources
Search for:
Admin Login

Posts classified under: Circadian and Sleep Medicine

Chris Colwell

Christopher Colwell, Ph.D.

Biography

Christopher S. Colwell is a Neuroscientist who has served on the UCLA School of Medicine faculty since he joined the Department of Psychiatry and Biobehavioral Sciences in 1997. He became a Professor in 2008. Dr. Colwell earned his B.S. in Neuroscience from Vanderbilt University in 1985. During this time, he started his research in circadian rhythms under the mentorship of Dr. T. Page. Dr. Colwell earned his Ph.D. in Biology at the University of Virginia in 1991. His thesis work explored the neural mechanisms by which light regulates circadian rhythms. Dr. Colwell continued this line of research during a postdoctoral fellowship at the University of Virginia with Dr. G. Block. A second postdoctoral fellowship was carried out on the topics of motor control and excitotoxicity in the laboratory of Dr. M. Levine at UCLA. Dr. Colwell learned how to utilize imaging techniques to measure calcium levels inside neurons while a visiting scientist in the laboratory of Dr. Konnerth at the University of Saarland, Germany. Since Dr. Colwell’s faculty appointment at UCLA, his laboratory’s research has focused on understanding the mechanisms underlying circadian rhythms in mammals. Dysfunction in the timing these daily cycles is a key symptom in a number of neurological and psychiatric disorders. Better understanding the basic biology of this timing system should result in new therapies to improve the quality of life of these patients and the people who care for them.

Paul M. Macey, Ph.D.

Paul Macey, Ph.D.

Biography

Paul M. Macey is a neuroscientist who has worked at UCLA since 1999. He is an Associate Professor of Nursing, and serves in the School of Nursing Administration as Director of Information Technology and Innovation, and Chief Innovation Officer. Dr. Macey completed a degree in Electrical Engineering at the University of Canterbury, New Zealand, where he focused on bringing engineering approaches to the analysis of breathing signals recorded from infants during sleep. He started at UCLA in a post-doctoral position in the Department of Neurobiology, and continued as and Assistant then Associate Researcher. Dr. Macey then joined the School of Nursing and Brain Research Institute as a faculty member. Dr. Macey teaches in the undergraduate Nursing program, and serves on various faculty committees.

Ketema Paul

Ketema Paul, Ph.D.

Biography

After receiving a bachelor’s degree in biology from Howard University I went on to study neurobiology and circadian biology at Georgia State University in Atlanta, Georgia where I received my doctorate in 2003. I completed a postdoctoral fellowship at Northwestern University in Evanston Illinois in 2006 at the Center for Sleep and Circadian Biology under the guidance of Dr. Fred Turek, after which I accepted a faculty position at the Morehouse School of Medicine (MSM). I spent ten years at MSM and joined the faculty at UCLA in 2016.

Research Interests

My work examines the genetic regulation of sleep and more importantly, how genetic heterogeneity influences the ability to recover from sleep loss. My research program currently has two foci: 1) to determine if disruptions of biological timing result in sleep-wake disorders and if so, which specific genes are involved and, 2) to determine if sex differences in the risk and severity of sleep abnormalities are chromosomally driven. My lab has recently undertaken a forward genetics approach to identify novel sleep genes. We have characterized a variety of sleep phenotypes in inbred mouse strains in sleep-replete and sleep-deprived conditions. We are expanding this dataset to provide sufficient statistical power for quantitative trait loci (QTL) analysis and subsequent follow-up studies. This endeavor combines a well-established paradigm of comparative phenotyping of a genetically tractable animal model with powerful genetic mapping tools to identify novel sleep-regulatory genes. Consequently, these experiments will not only identify new sleep genes, they will also help verify and clarify previously mapped genes whose roles are not yet clearly defined.

 

Education

B.S., Biology, Howard University 1994
Ph.D., Biology, Georgia State University 2003

 

Selected Publications

Ehlen, J.C., Brager, A.J., Baggs, J., Pinckney, L., Gray, C.L., Debruyne, J.P., Esser, K.A., Takahashi, J.S., Paul, K.N., “Bmal1 function in skeletal muscle regulates sleep”, eLife, 1-15 (2017) .

Clark, K.P., Ehlen, J.C., Paul, K.N., “Race and Gender Disparities in Sleep-Disordered Breathing”, Journal of Sleep Disorders: Treatment & Care, 6 (1): 1-4 (2017) .

Brager A.J., Heemstra, L., Bhambra, R., Ehlen, J.C., Esser, K., Paul, K.N., Novak, C. M., “Homeostatic effects of exercise and sleep on metabolic processes in mice with an overexpressed skeletal muscle clock”, Biochimie, 132 : 161-165 (2017) .

Brager, A.J., Yang, T., Ehlen, J.C., Simon, R.P., Meller, R., Paul, K.N., “Sleep is critical for remote preconditioning-induce neuroprotection”, Sleep, 39 : 2033-2040 (2016) .

Ehlen, J.C., Jones, K.A., Pinckney, L., Gray, C.L. Burette, S., Weinberg, R.J., Evans, J.A., Brager, A., Zylka, M.J., Paul, K.N., Philphot, B.D., Debruyne, J.P, “Maternal Ube3a loss disrupts sleep homeostasis but leaves circadian rhythmicity largely intact”, Sleep, 35 : 13587-13598 (2015) .

Evans, J.A., Suen, T-C., Calif, B., Mitchell, A., Castanon-Cervantes, O., Baker, K.M., Kloehn, I., Baba, K., Teubner, B.J.W., Ehlen, J.C., Paul, K.N., Bartness, T.J., Tosini, G., Leise, T.L., Davidson, A.J, “Shell neurons of the master circadian clock coordinate the phase of tissue clocks throughout the brain and body”, Sleep, 13 : 1-15 (2015) .

Jefferson, F., Ehlen, J.C., Williams, N.S., Paul, K.N, “A dopamine D2-receptor agonist attenuates the ability of stress to alter sleep in mice”, Sleep, 155 : 4411-4421 (2014) .

Ehlen, J.C., Jefferson, F. Brager, A.J., Benveniste, M., Paul, K.N., “Period-Amplitude Analysis Reveals Wake-Dependent Changes in the Electroencephalogram during Sleep Deprivation”, Sleep, 36 : 1723-1735 (2013) .

Brager, A.J., Ehlen, J.C., Castanon-Cervantes, O., Natarajan, D., Delisser, P., Davidson, A., Paul, K.N, “Sleep loss and inflammatory markers under chronic environmental circadian disruption”, Sleep, 8 : 1-8 (2013) .

Ehlen, J.C., Hesse S., Pinckney, L., Paul, K.N, “Sex chromosomes regulate nighttime sleep propensity during recovery from sleep loss”, Sleep, 8 : 1-6 (2013) .

Gina Poe, Ph.D.

Biography

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.

Education

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. https://doi.org/10.1007/s40675-021-00204-3.

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

1 2 3