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Pregnancy Timeline by SemestersFetal liver is producing blood cellsHead may position into pelvisBrain convolutions beginFull TermWhite fat begins to be madeWhite fat begins to be madeHead may position into pelvisImmune system beginningImmune system beginningPeriod of rapid brain growthBrain convolutions beginLungs begin to produce surfactantSensory brain waves begin to activateSensory brain waves begin to activateInner Ear Bones HardenBone marrow starts making blood cellsBone marrow starts making blood cellsBrown fat surrounds lymphatic systemFetal sexual organs visibleFinger and toe prints appearFinger and toe prints appearHeartbeat can be detectedHeartbeat can be detectedBasic Brain Structure in PlaceThe Appearance of SomitesFirst Detectable Brain WavesA Four Chambered HeartBeginning Cerebral HemispheresFemale Reproductive SystemEnd of Embryonic PeriodEnd of Embryonic PeriodFirst Thin Layer of Skin AppearsThird TrimesterSecond TrimesterFirst TrimesterFertilizationDevelopmental Timeline
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Home | Pregnancy Timeline | News Alerts |News Archive Feb 11, 2015

In the study, Luo and Choi manipulated puppet characters so they interacted in positive
and negative ways and found that the babies were able to comprehend what was happening.
Image Credit: You-jung Choi




Babies understand complex social situations

By one year old, infants begin to make sense of complex social situations by observing the behaviors of those around them.

The research was published in Psychological Science, a journal of the Association for Psychological Science. You-jung Choi, a doctoral candidate at the University of Missouri (MU), and Yuyan Luo, associate professor of psychological sciences in the College of Arts and Science, University of Missouri, created social situations using puppets and then studied the reactions of 13-month-old infants watching these performances.

Researchers brought 48 infants, each around 1 year old, into the lab for their experiment. Each infant sat on his or her parent's lap, facing a stage where hand puppets put on a show. First, two puppets appeared on stage acting friendly with each other. The two characters interacted in a positive manner — by clapping their hands, hopping around together and turning and looking at each other.

Then the infants were presented with several social scenarios. Each watched as a third puppet approached and was deliberately knocked down by one of the first pair as the other in that pair watched. In a second scenario, one puppet knocked down the third puppet, but the second puppet in the friendly pair wasn't around to see it happen. And in a third and final scenario, the third puppet was accidentally knocked down as one of the friendly pair looked on.

As infants can't tell us what they feel, researchers measured the amount of  time each infant spent observing each scenario. to interpret that infants' evaluation of the events seen.

Events that are routine or "expected" were interpreted as relatively boring to an infant, who quickly looked away. However, things that were unusual or unexpected were interpreted as more "interesting" to infants, as the baby spent more time observing the novel event.

When researchers analyzed an infant's observation time — they found infants responded to outcomes of the three scenarios differently, in accordance with accepted social expectations for each scenario.

"Our findings show that 13-month-olds can make sense of social situations using their own understanding and social evaluation skills. The research is innovative in that we show that infants are able to construe social situations from different participants' perspectives," said You-jung Choi.

Infants spent more time looking at puppet A when it was "friendly"  (wiggling and swaying) with puppet B. After the deliberate hit, then A ignored B. This suggests that the unfriendly interaction was an unexpected turn of events to the infant viewers.

"This to us indicates infants had strong feelings about how people should deal with a character who hits another. Perhaps expecting his or her [puppet] acquaintance or 'friend' should do something," say Choi and Luo.

However, when puppet A did not see the hit occur, infants stared longer when puppet A shunned puppet B than when puppet A was friendly to puppet B. This "staring" indicates that infants were tracking what puppet A knew and didn't know and using that information to make assumptions about A's behavior.

"These scenarios are a bit like adults witnessing their friends behaving badly," said Luo. "If you were to witness your friend hitting another person, you'd tend to avoid him or her. If you had not witnessed the hit, you still would hang out with the friend. If the hit were an accident, then you may or may not spend time with them. Our results showed that babies reacted to these scenarios in similar ways. "

The results suggest that young children are developing skills that enable them to assess social situations, Luo said. "For adults, the answers to these questions are probably complicated, depending on various factors such as the nature of the friendship and both parties' personalities," said Choi. "However, we feel that what we're witnessing is the beginning of how we assign meaning to social situations later in life."

When a hit was by accident, infants spent about the same amount of time looking at each puppet in the two outcomes. They seemed to respond to the friendly outcome and unfriendly outcome as equally reasonable.

Choi and Luo believe these results suggest young children are developing skills to enable them to assess social situations and make relevant social judgments. All much earlier than many adults would assume.

These results suggest that young children are developing skills that enable them to assess social situations, Luo added. Future research involves investigating social interactions where infants witness prosocial acts such as helping or assisting the puppet who was hit and how the babies react to that dynamic.

In the present research, we investigated how 13-month-olds use their emergent theory-of-mind understanding (i.e., understanding about other people’s mental states, such as their intentions, perceptions, and beliefs) and social-evaluation skills to make sense of social interactions. The infants watched three puppets (A, B, and C) interact. The results showed that after seeing Agents A and B interact in a positive manner, infants expected them to continue doing so, even after they saw B hit another agent, C, while A was absent. When A was present to witness B’s harmful action, however, infants expected A to change his or her behavior and ignore B. Therefore, infants seemed to consider A’s perspectives when predicting A’s actions. Furthermore, if B accidentally hit C when A was present, infants seemed to accept that A could interact or not interact with B, which suggests that they had taken into account B’s intention in their interpretations of the agents’ interactions.

The APS journal Psychological Science is the highest ranked empirical journal in psychology. For a copy of the article "13-Month-Olds' Understanding of Social Interactions" and access to other Psychological Science research findings, please contact Anna Mikulak at 202-293-9300 or amikulak@psychologicalscience.org.

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