Infragranular barrel cortex activity is enhanced with learning.
The barrel cortex (BC) is essential for the acquisition of whisker-signaled trace eyeblink conditioning and shows learning-related expansion of the trained barrels after the acquisition of a whisker-signaled task. Most previous research examining the role of the BC in learning has focused on anatomic changes in the layer IV representation of the cortical barrels. We studied single-unit extracellular recordings from individual neurons in layers V and VI of the BC as rabbits acquired the whisker-signaled trace eyeblink conditioning task. Neurons in layers V and VI in both conditioned and pseudoconditioned animals robustly responded to whisker stimulation, but neurons in conditioned animals showed a significant enhancement in responsiveness in concert with learning. Learning-related changes in firing rate occurred as early as the day of learning criterion within the infragranular layers of the primary sensory cortex.
Dept. of Physiology, Interdepartamental Neuroscience Program, Northwestern Univ., Chicago, IL 60611, USA. RebekahWard2008@u.northwestern.edu
Rebekah L
RL
Ward
Luke C
LC
Flores
John F
JF
Disterhoft
D000200:Action Potentials / Q000502:physiology; D000704:Analysis of Variance; D000818:Animals; D001767:Blinking / Q000502:physiology; D003214:Conditioning, Classical / Q000502:physiology*; D003576:Electron Transport Complex IV / Q000378:metabolism; D005260:Female; D009474:Neurons / Q000502:physiology*; D010812:Physical Stimulation / Q000379:methods; D011817:Rabbits; D013003:Somatosensory Cortex / Q000166:cytology / Q000378:metabolism / Q000502:physiology*; D014738:Vibrissae / Q000294:innervation / Q000502:physiology*
D003576:Electron Transport Complex IV