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<div align="center"><font face="Arial" size="+1" color="#0000FF">The
Department of Brain & Cognitive Sciences is pleased to
announce:</font></div>
<div align="center"><font face="Arial" size="+1" color="#0000FF">The
8th Annual Margaret Bidwell Memorial Lecture</font></div>
<div align="center"><font size="+1"> </font></div>
<div align="center"><font face="Arial" size="+1" color="#0000FF">Peter
Strick, PhD</font></div>
<div align="center"><font face="Arial" size="+1"
color="#0000FF">Professor, Department of Neurobiology, and Co-director
Center for the Neural Basis of Cognition (CNBC)</font></div>
<div align="center"><font face="Arial" size="+1"
color="#0000FF">University of Pittsburgh</font></div>
<div align="center"><font face="Arial" size="+1"
color="#0000FF"><i>Building blocks for movement in the motor
cortex</i></font></div>
<div align="center"><font size="+1"> </font></div>
<div align="center"><font face="Arial" size="+1" color="#0000FF">4:00
PM, Tuesday April 11th, 2006</font></div>
<div align="center"><font face="Arial" size="+1"
color="#0000FF">46-3002 Auditorium</font></div>
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<div><font face="Arial" color="#0000FF">Abstract:</font></div>
<div><font face="Arial" color="#0000FF">How are the cortical neurons
that control a muscle distributed in the primary motor cortex (M1)?
To answer this classical question we used retrograde transneuronal
transport of rabies virus from single muscles of macaques. This
enabled us to define cortico-motoneuronal (CM) cells that make
monosynaptic connections with the motoneurons of the injected muscle.
We examined the distribution of CM cells that project to motoneurons
of 3 thumb and finger muscles. We found that the CM cells for
these digit muscles are restricted to the caudal portion of M1 which
is buried in the central sulcus. Within this region of M1, CM
cells for one muscle display a remarkably widespread distribution and
fill the entire mediolateral extent of the arm area. In fact, CM
cells for digit muscles are found in regions of M1 that are known to
contain the shoulder representation. The cortical territories
occupied by CM cells for different muscles overlap extensively.
Thus, we found no evidence for a focal representation of single
muscles in M1. Instead, the overlap and intermingling among the
different populations of CM cells may be the neural substrate to
create a wide variety of muscle synergies. Indeed, we will
present physiological evidence that the task of the motor cortex is to
function as a flexible central pattern generator.</font></div>
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