Figure 5.

Amygdala-lesioned infants failed to demonstrate a species-typical preference for their mother after separation from their mother, as indicated by measure of proximity duration, distance, and distress responses. a, Bars represent the average time ± SEM (per 120 sec trial) spent in a 1 m semicircle “proximity zone” in front of the holding cages that contain either their mother (M) or the stimulus female (S). Proximity duration was scored only when the infant stayed within the proximity zone for at least 3 consecutive seconds. Asterisks denote significant paired t tests (p < 0.05). b, Bars represent the average distance from the mother (meters) ± SEM. Spacing data were collected every 15 sec during the 120 sec trial, noting the location of the infant on a 27 quadrant floor grid. Asterisks denote significant post hoc Fisher's PLSD tests (significance set at p < 0.05). c, Bars represent the average scream frequency ± SEM per 120 sec trial. The frequency of scream data were not normally distributed and contained a number of zero values. Therefore, a ln(scream + 1) transformation was used. For display purposes, the nontransformed scream data are shown. Asterisks denote significant post hoc Fisher's PLSD tests (significance set at p < 0.05).