Early‐life malnutrition selectively retards the development of distal‐ but not proximal‐cue navigation

Abstract

The effects of early-life malnutrition on the distal-cue and proximal-cue versions of the Morris (1981) water maze were studied with different-aged rats. Consistent with the existing literature, malnutrition only mildly influenced the distal-cue navigation of relatively old pups (30 day olds). Pups 20–27 days old, however, displayed no evidence of distal-cue navigation if they had been malnourished previously. Malnutrition had no effect on proximal-cue based navigation by pups at any age. The effect of malnutrition on distal-cue performance could not be attributed to any general debilitating effects, sensory, motor, or motivational deficits. Instead, it appears to selectively influence the development of the neural system (perhaps the hippocampus and related structures) more directly involved in learning to utilize distal cues.