for the Analysis of Brain Circuits Mediating Behavior
lab is interested in brain circuitry mediating skilled motor learning. We want to know how motor circuitry is
assembled, how it is activated during motor learning, how it contributes to
specific aspects of behavior, and how it is modified by experience. To address these questions, we use an array
of viral and genetic tools to examine and manipulate brain circuitry with a
high degree of spatial and temporal precision.
A variety of targeted viral tracers allow us to trace projections of functionally-defined
cell populations and then characterize both pre- and post-synaptic
connections. Targeted neuronal silencing
(using DREADDs or PSAM systems), activation (channelrhodopsin-2), along with
targeted neuronal ablation (using diphtheria toxin system) are used to dissect
the functional contribution of distinct aspects of motor circuitry to the
acquisition and performance of skilled motor behavior. Finally, in vitro whole cell approaches are
used to explore more subtle details regarding how brain circuitry becomes
modified by experience and learning.
- Wang L,
Conner JM, Rickert J, Tuszynski MH (2011) Structural plasticity within highly
specific neuronal populations identifies a unique parcellation of motor
learning in the adult brain. Proc Natl Acad Sci U S A 108:2545-2550.
- Biane JS,
Scanziani M, Tuszynski MH, Conner JM. (2015) Motor cortex maturation is associated with reductions in
recurrent connectivity among functional subpopulations and increases in
intrinsic excitability. J Neurosci.
- Biane JS,
Takashima, Y., Scanziani M, Conner, JM, Tuszynski MH (2015) Thalamocortical
Projections Exhibit Plasticity Onto Behaviorally-Relevant Neurons During Adult
Motor Learning. Neuron (in press).
- Wang, L., Conner, J.M., and M.H. Tuszynski
(2015) Rehabilitation Drives Enhancement of Neuronal Structure in Functionally
Relevant Neuronal Subsets: Cholinergic Dependence. PNAS (in press).
are also interested in underlying mechanisms that enable experience-dependent
plasticity. Prior studies by our group
have demonstrated the critical role of the basal forebrain cholinergic system
for permitting experience dependent plasticity in the context of behavior. Highly specific lesions of cholinergic forebrain
systems abolish plasticity mediated by a learning experience. Both brain map reorganization and structural modifications
normally driven by experience are completely abolished following targeted
removal of cortical cholinergic afferents and behavior is markedly
compromised. Future studies will examine
the cellular and synaptic basis for cholinergic actions in mediating
- Conner, J.M., A.C. Culberson. C. Packowski,
A. Chiba and M.H. Tuszynski (2003) Lesions of the
basal forebrain cholinergic system impair task acquisition and abolish cortical
plasticity associated with motor skill learning. Neuron 38:819-829.
- Conner, J.M., A. Chiba and M.H. Tuszynski
(2005) The basal forebrain cholinergic system is
essential for cortical plasticity and functional recovery following brain
injury. Neuron 46: 173-179.
- Ramanathan, D.R, M.H. Tuszynski and J.M.
Conner. (2009) The basal forebrain cholinergic system required specifically for
behaviorally mediated cortical map plasticity. J. Neuroscience 29: 5992-6000.
complete bibliography of past work can be found here.
James Conner, PhD