Tuesday, December 15, 2015

Infants Need to Hear Adults Talk


By the time kids start school, there are already differences among them in their language abilities.  These early differences can have an enormous impact on their performance in school, because teachers do most of their instruction by talking to kids. 
Where do these early differences come from?
A growing body of evidence suggests that a huge influence on early language development is the number of words that children hear as infants and toddlers.  The more that parents speak to their infants and in front of their infants, the better infants get at understanding speech and learning words.
This issue has been explored in some previous work that has compared children who grow up in low socioeconomic status (SES) and high SES homes.  An interesting paper in the November, 2013 issue of Psychological Science by Adriana Weisleder and Anne Fernald examined this question just within a sample of low SES Spanish speaking homes in the United States.
They had 19-month-old infants wear an audio recorder for at least one full day.  Many infants wore the recorder for several days, and the longest recording day was selected. 
Using software, the recordings were analyzed to identify all of the words spoken in the infants’ presence during that day.  In addition, the researchers classified the speech by whether it was directed at the infants or whether it was just speech that the infants overheard.
Both when the infants were 19-months-old and again when they were 24-months-old, the researchers measured their efficiency at understanding speech.  In these tests, the infants were seated in front of a screen.  They saw pairs of pictures displaying common objects (like a dog or a ball).  They heard the Spanish word for one of those pictures spoken and the researchers measured how much the infant looked at the picture corresponding to the spoken word as well as how quickly the infant looked at that picture after the word was spoken.  In addition, at 24 months, the parents used a checklist to estimate the size of their child’s vocabulary.
Within this sample, there was a huge difference in the number of words that the infants heard.  Some infants heard fewer than 2000 words in a day, while some heard over 15,000.  In addition, there were big differences in child-directed speech.  Some families spoke fewer than 1000 words to their children in a day, while others spoke over 10,000 words to their children.
The number of words spoken to children at 19 months was a significant predictor of the child’s vocabulary at 24 months.  In addition, the number of words spoken to children predicted how quickly and effectively children looked at the picture associated with a word they heard.  Statistical analysis demonstrated that the ease of identifying the words in speech was an important reason why infants who heard more words had a larger vocabulary at 24-months than infants who heard fewer words.
This early language experience compounds itself over time.  Not only do infants who hear lots of words understand language better than those who hear fewer words, they are also more likely to start vocalizing and speaking words earlier.  When children talk more, adults talk back to them more often.  So, the early advantage in language ability gets bigger over time.
This research demonstrates the importance of a rich environment for infants.  Infant brains are developing rapidly, and that brain development is strongly influenced by what is going on around them.  The more that these infants are embedded in a complex language environment, the more that their language abilities develop.  And that early development gives them a huge advantage as they start school.

Monday, December 7, 2015

When Is It Good To Choose?


High School students often complain about the classes that they are taking.  Their course of study is largely laid out for them, and so they have few choices of the subjects they take.  The lack of choice can be demotivating.  When those students get to college, though, an interesting thing happens.  Suddenly, they have almost an infinite amount of choice.  They can select the courses they want.  At that point, the number of options can feel completely overwhelming.  

So, is it better for your motivation and performance if you are allowed to choose what you want to do or if the choice is made for you?

This question was explored in paper in the Journal of Experimental Social Psychology paper published in 2013 by Erika Patall, Breana Sylvester, and Cheon-woo Han.  They suggest that the influence of choice on motivation and performance depends on people’s competence at the task.  When people have some expertise in a task, then they are more motivated when they can choose what they are doing than when the choice is made for them.  When people are not experts, then they are actually most motivated when the choice is made for them.

In one study, participants played a word game in which they had to form as many words as they could from a set of letters given to them.  Before playing the game, they were given a test of verbal ability and were randomly assigned to get feedback that they were either among the top or among the bottom scorers on this test.  The feedback was designed to manipulate how people felt about their competence at playing these games relative to their peers.

Some participants were given the choice between playing one of two games (which were labeled Text Twist and Boggle), a choice between having games of medium difficulty, or games of a range of easy, medium, and hard difficulty, and a choice between playing rounds for 2-minutes at a time or playing for a total of 20 minutes.  Other participants were assigned to a combination of these factors.      

Participants then reported whether they thought they would do well in these games and their motivation to succeed.  Afterwards, did the puzzles.  (The two formats and difficulty levels were actually identical, so participants ultimately did all of the same puzzles regardless of the combination they chose or to which they were assigned.)  After completing the games participants were asked how motivated they were to complete the puzzles and how much they enjoyed them.  

The manipulation of competence was successful.  People who were given feedback that they scored well on the test of verbal ability rated themselves as more competent at these puzzles than those who were told that they scored poorly.  

Participants who could choose for themselves were more motivated to do the puzzles and performed better when they rated themselves as good at these puzzles than when they saw themselves as bad at them.  People who had the choice made for them showed the opposite pattern.  They were more motivated and performed better when felt they were bad at puzzles than when they felt they were good at them.  

This pattern is actually reflected in people’s judgments of what they would do in real-life situations.  In another study, participants who performed a survey using Amazon’s Mechanical Turk were asked whether they would prefer to choose a job or be assigned one in a work situation in which they knew they were good at the task or in which they knew they were not so good at it.  Participants had a stronger preference to choose their job when it was something they knew they were good at than when it was something they knew they were not good at.  

These findings are valuable for anyone who is managing a group.  In order to increase people’s enjoyment of what they are doing and their motivation to continue, it is important to match the freedom they have to choose to the expertise they believe they have.  People who see themselves as experts want choice, while those who see themselves as novices prefer to be given an assignment.