Pretest administration of glucose attenuates infantile amnesia for passive avoidance conditioning in rats.
Infantile amnesia in rats may be attenuated by a wide variety of retrieval cues which reactivate memory for the training episode. The present study investigated the effects of glucose on memory retrieval in infant rats. In Experiment 1, 17-day-old preweanling rats were trained to criterion on passive avoidance conditioning. Twenty-four hours later, each subject received a subcutaneous injection of either saline, 100 mg/kg, or 250 mg/kg of glucose just prior to testing. Saline animals displayed poor retention scores, suggesting infantile amnesia; however, glucose significantly attenuated the 24-hr retention loss. Experiment 2 attempted to replicate the previous experiment, control for age and general drug effects, and extend the dose of glucose to 400 mg/kg. The results of Experiment 2 were consistent with Experiment 1 and also indicated that infant subjects performed significantly worse than adults. Both 100 and 250 mg/kg of glucose significantly attenuated infantile amnesia; however, 400 mg/kg had no effect. These results support a retrieval failure view of infantile amnesia and extend the memory-influencing properties of glucose to infants. Context and neuroendocrine views of memory retrieval are discussed.
Flint
R W
RW
Department of Psychology, Mankato State University, MN 56002-8400, USA.
Riccio
D C
DC
D000367:Age Factors; D000818:Animals; D001362:Avoidance Learning / Q000502:physiology*; D001786:Blood Glucose / Q000502:physiology*; D003214:Conditioning, Classical / Q000502:physiology*; D005950:Glucose Solution, Hypertonic / Q000008:administration & dosage; D007231:Infant, Newborn; D011939:Mental Recall / Q000502:physiology*; D009042:Motivation; D011292:Premedication; D051381:Rats; D017207:Rats, Sprague-Dawley; D012153:Retention, Psychology / Q000502:physiology
D001786:Blood Glucose; D005950:Glucose Solution, Hypertonic