Volume 9 Num. 2 - June 2009
Orbitofrontal Cortex Inactivation Impairs Early Reversal Learning in Male Rats During a Sexually Motivated Task
Volume 9 Num. 2 - June 2009 - Pages 141-160
Miguel Angel Guevara P?rez , Francisco Abelardo Robles Aguirre , Gina Lorena Quirarte , Marisela Hern?ndez Gonz?lez
This study analyzes whether inactivation of the orbitofrontal cortex (OFC) affects early
discrimination or reversal learning during a T maze motivated task. Male rats received saline
solution or one doses of tetrodotoxin (TTX) bilaterally into the OFC, and were permitted to
have an intromission with a receptive female to induce a sexually motivated state. Discrimination
and reversal sessions consisted of seven trials each to accomplish the non-overtrained condition.
Each arm of the T maze was associated to different external cues. Subjects were sexually
reinforced whenever they reached the receptive female box, and returned to the start-box if
not. Spontaneous motor activity was not altered. Rats with OFC inactivated did not present
alteration during discrimination. Males with higher doses of TTX had a deficit in the number
of correct responses and increased number of trials without response during reversal learning.
These data agrees with other studies and indicates that an intact OFC is essential for the
adequate manifestation of reversal learning during its early phase in motivated tasks. However,
disagrees with other findings about early perseverative responses, pointing out to a critical
role of this structure in enhancing performance through incentive value re-assignment of
predicted outcome cues.
orbitofrontal cortex, reversal learning, sexual motivation, T maze, tetrodotoxin