Murray and Tervarthen (1985) studied two-month-old infants using interactions with their mothers via a video monitor
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When mothers did not interact with their infants, via the monitor, infants showed distress and tried to attract their mother's attention. The infants independently showed a response rather than showing a behaviour that had been rewarded by the mother replicating it back
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This suggests that the infant is an active and intentional partner in the infant-caregiver relationship