[BIC-announce] FW: Killam Lecture - TODAY - Visual processing in complete cortical microcircuits revealed with two-photon calcium imaging in vivo

[Jennifer Chew, Ms.]

PLEASE DISCARD IF THIS IS A DUPLICATE.  THANK YOU. JENNIFER  
 
_______________________________

From: MNISTAFF - Montreal Neurological Institute Staff [mailto:MNISTAFF at LISTS.MCGILL.CA] On Behalf Of Enza Ferracane, Ms.
Sent: Tuesday, September 11, 2007 8:44 AM
To: MNISTAFF at LISTS.MCGILL.CA
Subject: Killam Lecture - TODAY

-----------REMINDER------------
Dear Colleagues,

Our Killam speaker for Tuesday, September 11, 2007 at 4:00 p.m. in the de Grandpré Communications Centre <http://neuromedia.mcgill.ca/mnibooking/week.php?year=2007&month=09&day=07&area=3&room=4>  (MNI), is Dr. Prakash Kara from the Medical University of South Carolina, Department of Neurosciences.  

The title of his talk is: 

"Visual processing in complete cortical microcircuits revealed with two-photon calcium imaging in vivo".

ABSTRACT:
The mammalian brain has more than a billion cells. This staggering number makes it difficult to determine the mechanisms by which the brain accomplishes its repertoire of functions. Even within one region, like the cortical area that processes vision, cells respond to visual stimuli that have very specific orientations and directions of motion. Lagging far behind our understanding of the representation of orientation and direction of sensory stimuli is the representation of binocular vision in the brain. Aside from the difficulty in being able to monitor the activity of complete populations of neurons in local microcircuits (with single-cell resolution), a contributing factor to the lack of progress on the neural basis of binocular vision is that the dominant approach for assaying binocular properties of cortical neurons employs monocular tests of ocular dominance to infer binocular function. This almost never occurs naturally. Furthermore, it is widely assumed that binocular vision is not essential for the survival of many vertebrate (and invertebrate) species. It turns out that binocular vision in invertebrate predators (like the praying mantis) and vertebrate predators (such as cats) is essential for survival as the ability to detect small differences in inter-ocular retinal disparities is the only means to gain access to the third dimension of visual space for accurately tracking moving objects such as prey. In mammals, the first neurons along the visual pathway from eye to brain that can code for binocular disparities are found in the visual cortex. When discrete functional domains are relatively small (~100 um), single-unit recordings can provide misleading results. Consequently, the relative contribution of phase vs. position disparity tuning, the dependence of disparity on motion selectivity and the relationship between ocular dominance and disparity selectivity are all poorly understood and hotly debated. My lab has attempted to resolve these issues on binocular vision by using in vivo two-photon calcium imaging of neuronal cell bodies as a surrogate for spiking activity.

 

I am looking forward to seeing you all there.

Christopher Pack, Ph.D.

 

 

Naomi Takeda 

Administrative Coordinator for:

Drs. Barbara E. Jones, David S. Ragsdale,

        Christopher C. Pack and T. Stroh

Montreal Neurological Institute

McGill University

3801 University Street, #896

Montreal, Quebec, Canada

H3A 2B4

(  514-398-1913

Ê  514-398-5871

: naomi.takeda at mcgill.ca