When they first arrived in the UK, ½ of the orphans showed signs of delayed intellectual development and the majority were severely undernourished. At age 11, there were differential rates of recovery (related to the age of adoption). The mean IQ when adopted before 6 months was 102 vs 77 when adopted after 2 years (critical period). The children who were adopted after 6 months showed a disinhibited attachment (showing attention-seeking, clingy behaviour to all adults, familiar and non-familiar).