| |
| |
| Dietmar Plenz, Ph.D., Investigator |
 |
Dr. Plenz received his Diploma from the University of Tuebingen in 1990. He received his Ph.D. in 1993 at the Max-Planck Institute of Biological Cybernetics/University Tuebingen where he studied the electrophysiological characteristics of neurons from cortex and basal ganglia in vitro with Professors Ad Aertsen and Valentino Braitenberg. After a postdoctoral fellowship with Stephen T. Kitai at the University of Tennessee, Memphis, analyzing neuronal population activity in isolated cortex-basal ganglia systems, he joined the faculty in the Department of Neuroanatomy and Neurobiology. Dr. Plenz joined the NIMH as an Investigator in 1999. His laboratory explores the function of basic activity patterns and the conditions under which they arise in neuronal networks of cortex and basal ganglia.
|
|
Staff:
- Mr. Timothey Bellay, B.Sc., IRTA Fellow, (301) 451-2884 bellayt@mail.nih.gov
- Dr. Avrama Blackwell, Ph.D., Adjunct Investigator, (301) 402-2255 avrama@gmu.edu
- Dr. Gireesh Elakkat Dharmaraj, M.B.B.S., Postdoctoral Fellow, (301) 451-2868 elakkat@mail.nih.gov
- Mrs. Agatha Monzon, B.Sc., IRTA Fellow, (301) 402-2255 monzona@mail.nih.gov
- Dr. Sinisa Pajevic, Ph.D., Staff Scientist, (301) 435-5049 pajevic@helix.nih.gov
- Dr. Thomas Petermann, Ph.D., Postdoctoral Fellow, (301) 451-8996 petermannt@mail.nih.gov
- Dr. Woodrow Shew, Ph.D., Postdoctoral Fellow, (301) 451-3048 sheww@mail.nih.gov
- Mr. Craig V. Stewart, M.S., Research Assistant, (301) 402-6820 stewartc@intra.nimh.nih.gov
- Dr. Tara Thiagarajan, Postdoctoral Fellow, (301) 402-2255 tarat@mail.nih.gov
Research Interests:
Critical self-organization of neural networks is a central question in neuroscience. How does the brain achieve and maintain activity states at which information processing is possible? The Unit of Neural Network Physiology aims at the understanding of critically self-organized network states in the mammalian forebrain, specifically in cortex-basal ganglia circuits. A cortical area or nucleus of the basal ganglia contains hundreds of thousands of neurons that act in a collective way upon each other. Knowledge of individual neuron properties is insufficient to predict the number of activity patterns such networks can generate. The task is even more challenging when networks between different brain structures are considered.
We use electrophysiological, computational, pharmacological, and molecular biological methods to study self-organized criticality in cortical networks. Specific questions relate to the intranucleus generation of network activities, network stability, and the dynamic characteristics of single neurons embedded in such network activity. Recent research from my laboratory has demonstrated a previous unknown type of synchronized cortical activity, which we called 'neuronal avalanches'. Neuronal avalanches arise in superficial cortical layers and occur when the network is in the critical state. We study the origin, stability, and functions of neuronal avalanches in vitro as well as in vivo in the awake monkey.
Our experimental strategies and conceptual approaches allow for a detailed classification of normal and abnormal neuronal activity patterns that have been observed in human neurological diseases and corresponding animal models (i.e. Schizophrenia and Parkinson's disease). Insights into critically self-organized network states will provide essential information for our understanding of these mental and neurological disorders.
|
Selected Recent Publications:
Plenz D, Thiagarajan T (2007) The organizing principles of neuronal avalanches: cell assemblies in the cortex, TINS 30, 101 - 110.
Stewart CV, Plenz D (2006) Inverted-U profile of dopamine-NMDA-mediated spontaneous avalanche recurrence in superficial layers of rat prefrontal cortex, J Neurosci 26, 8148-8159.
Kotaleski JH, Plenz D, Blackwell KT (2006) Using potassium currents to solve signal-to-noise problems in inhibitory, J Neurophysiol 95, 331-341.
Petridou N, Plenz D, Silva AC, Loew M, Bodurka J, Bandettini PA (2006) Direct magnetic resonance detection of neuronal electrical activity., Proc Natl Acad Sci U S A 103, 16015-16020.
Plenz D (2005) Comment on 'Critical branching captures activity in living neural networks and maximizes the number of metastable states', Phys Rev Lett 95, 219801.
Gustafson N, Gireesh-Dharmaraj E, Czubayko U, Blackwell KT, Plenz D (2005) A comparative voltage and current-clamp analysis of feedback and feedforward synaptic transmission in the striatal microcircuit in vitro., J Neurophysiol 95, 737-752.
Kerr JN, Plenz D (2004) Action potential timing determines dendritic calcium during striatal up-states, Journal of Neuroscience 24, 877-885.
All Selected Publications
Contact Information:
Dr. Dietmar Plenz
Laboratory of Systems Neuroscience, NIMH
Porter Neuroscience Research Center
Building 35, Room 3A-100
35 Convent Drive, MSC 3726
Bethesda, MD 20892-3726
Telephone: (301) 402-2249 (office),
(301) 402-2249 (laboratory),
(301) 402-8960 (fax)
Email: plenzd@intra.nimh.nih.gov
|
|
