Postnatal handling of rat pups alters their response to novelty. We have now shown that, as adults, rats handled for the first three weeks of life showed a suppression of feeding in a novel environment that was less, and a [3H]flunitrazepam binding in whole brain that was greater than in non-handled animals. These data suggest that variations in benzodiazepam binding capacity could be related to individual differences in the fear response to novelty.