Research often takes place in a lab meaning that this increases the validity and reliability of the studies.
However, it may also mean that the study may lack ecological validity.
Practical issues
Because babies sleep a lot study a baby when they may not be fully awake may not be very valid.
However, it can be increased by doing observations for short time periods.
Contradictory evidence
Feldman (2012)- found that synchrony and reciprocity simply define behaviour that occurs but it doesn’t tell us their purpose or why they happen.
Supporting evidence
There is evidence that reciprocity and interactional synchrony are helpful in mother infant interaction and reduce stress and increase language and moral development of the infant.
