title: Summation of connectivity strengths in the visual cortex reveals stability of neuronal microcircuits after plasticity.
abstract: BACKGROUND
  Within sensory systems, neurons are continuously affected by environmental stimulation. Recently, we showed that, on cell-pair basis, visual adaptation modulates the connectivity strength between similarly tuned neurons to orientation and we suggested that, on a larger scale, the connectivity strength between neurons forming sub-networks could be maintained after adaptation-induced-plasticity. In the present paper, based on the summation of the connectivity strengths, we sought to examine how, within cell-assemblies, functional connectivity is regulated during an exposure-based adaptation.
  
  
  RESULTS
  Using intrinsic optical imaging combined with electrophysiological recordings following the reconfiguration of the maps of the primary visual cortex by long stimulus exposure, we found that within functionally connected cells, the summed connectivity strengths remain almost equal although connections among individual pairs are modified. Neuronal selectivity appears to be strongly associated with neuronal connectivity in a "homeodynamic" manner which maintains the stability of cortical functional relationships after experience-dependent plasticity.
  
  
  CONCLUSIONS
  Our results support the "homeostatic plasticity concept" giving new perspectives on how the summation in visual cortex leads to the stability within labile neuronal ensembles, depending on the newly acquired properties by neurons.
authors.affiliation: Laboratoire de Neurosciences de la vision, Département de Sciences Biologiques, Université de Montréal, CP 6128 Succ. Centre-Ville, Montréal, QC, H3C 3J7, Canada. lyes.bachatene@umontreal.ca.|Neurosciences Computationnelles et Traitement Intelligent des Signaux (NECOTIS), Département de Génie Électrique et Génie Informatique, Université de Sherbrooke, Sherbrooke, QC, Canada. lyes.bachatene@umontreal.ca.
authors.forename: Lyes
authors.initials: L
authors.lastname: Bachatene
authors.affiliation: Laboratoire de Neurosciences de la vision, Département de Sciences Biologiques, Université de Montréal, CP 6128 Succ. Centre-Ville, Montréal, QC, H3C 3J7, Canada. vishal.bharmauria@umontreal.ca.|Neurosciences Computationnelles et Traitement Intelligent des Signaux (NECOTIS), Département de Génie Électrique et Génie Informatique, Université de Sherbrooke, Sherbrooke, QC, Canada. vishal.bharmauria@umontreal.ca.
authors.forename: Vishal
authors.initials: V
authors.lastname: Bharmauria
authors.affiliation: Laboratoire de Neurosciences de la vision, Département de Sciences Biologiques, Université de Montréal, CP 6128 Succ. Centre-Ville, Montréal, QC, H3C 3J7, Canada. sarah.cattan@umontreal.ca.|Neurosciences Computationnelles et Traitement Intelligent des Signaux (NECOTIS), Département de Génie Électrique et Génie Informatique, Université de Sherbrooke, Sherbrooke, QC, Canada. sarah.cattan@umontreal.ca.
authors.forename: Sarah
authors.initials: S
authors.lastname: Cattan
authors.affiliation: Laboratoire de Neurosciences de la vision, Département de Sciences Biologiques, Université de Montréal, CP 6128 Succ. Centre-Ville, Montréal, QC, H3C 3J7, Canada. nayan.chanauria@umontreal.ca.|Neurosciences Computationnelles et Traitement Intelligent des Signaux (NECOTIS), Département de Génie Électrique et Génie Informatique, Université de Sherbrooke, Sherbrooke, QC, Canada. nayan.chanauria@umontreal.ca.
authors.forename: Nayan
authors.initials: N
authors.lastname: Chanauria
authors.affiliation: Laboratoire de Neurosciences de la vision, Département de Sciences Biologiques, Université de Montréal, CP 6128 Succ. Centre-Ville, Montréal, QC, H3C 3J7, Canada. jean.rouat@usherbrooke.ca.|Neurosciences Computationnelles et Traitement Intelligent des Signaux (NECOTIS), Département de Génie Électrique et Génie Informatique, Université de Sherbrooke, Sherbrooke, QC, Canada. jean.rouat@usherbrooke.ca.
authors.forename: Jean
authors.initials: J
authors.lastname: Rouat
authors.affiliation: Laboratoire de Neurosciences de la vision, Département de Sciences Biologiques, Université de Montréal, CP 6128 Succ. Centre-Ville, Montréal, QC, H3C 3J7, Canada. stephane.molotchnikoff@umontreal.ca.|Neurosciences Computationnelles et Traitement Intelligent des Signaux (NECOTIS), Département de Génie Électrique et Génie Informatique, Université de Sherbrooke, Sherbrooke, QC, Canada. stephane.molotchnikoff@umontreal.ca.
authors.forename: Stéphane
authors.initials: S
authors.lastname: Molotchnikoff
mesh_terms: D000222:Adaptation, Physiological / Q000502:physiology*; D000818:Animals; D002415:Cats; D055724:Electrophysiological Phenomena; D005260:Female; D008297:Male; D009415:Nerve Net / Q000502:physiology*; D009473:Neuronal Plasticity / Q000502:physiology*; D009474:Neurons / Q000502:physiology*; D061848:Optical Imaging; D010364:Pattern Recognition, Visual / Q000502:physiology*; D014793:Visual Cortex / Q000502:physiology*