Olfactory aversive conditioning in the newborn (3-hr-old) rat impairs later suckling for water and milk.
An olfactory conditioning paradigm tested whether newborn rats can acquire a conditioned aversion to olfactory events associated with their first postnatal meal 3-5 hr after birth. Exposure to lemon odor (conditioned stimulus [CS]) paired with intraoral infusions of 0.1% quinine (unconditioned stimulus) resulted in explicit conditioning. Responsiveness to a surrogate nipple providing water in the presence of the CS was significantly lower than the 3 control conditions. The conditioning dramatically suppressed responsiveness to a surrogate nipple providing milk, which normally is expressed voraciously in terms of sustained nipple attachment and milk intake. These findings suggest that as early as 3-5 hr after birth newborn rats are capable of aversive conditioning to odors in the context of suckling behavior.
Nizhnikov
Michael E
ME
Department of Psychology, State University of New York at Binghamton, Box 6000, Binghamton, New York 13902-6000, USA. bh08588@binghamton.edu
Petrov
Evgeniy S
ES
Spear
Norman E
NE
D000818:Animals; D000831:Animals, Newborn; D003213:Conditioning, Psychological / Q000502:physiology*; D005260:Female; D008297:Male; D008892:Milk; D011897:Random Allocation; D051381:Rats; D017207:Rats, Sprague-Dawley; D012903:Smell / Q000502:physiology*; D013391:Sucking Behavior / Q000502:physiology*; D014867:Water
D014867:Water