According to a new study，teens focus on rewards and have a hard time learning to avoid punishment or consider the consequences of alternative actions.
   University College London researchers compared how teens and adults learn to make choices based on the available information.They tracked the way in which 18 volunteers aged 12-17 and 20 volunteers aged 18-32 completed tasks in which they had to choose between abstract symbols.
   Each symbol was consistently associated with a fixed chance of a reward，punishment，or no outcome.Teens and adults were equally good at learning to choose symbols associated with reward，but teens were less good at avoiding symbols associated with punishment.
   "From this experimental lab study we can draw conclusions about learning during the teen years.We find that teens and adults learn in different ways，something that might be relevant to education，" said lead author Dr.Stefano Palminteri. "Unlike adults，teens are not so good at learning to adjust their choices to avoid punishment.This suggests that incentive（鼓勵(lì)）systems based on reward rather than punishment may be more effective for this age group."
   To interpret the results，the researchers developed computational models of learning and ran simulations（模擬）applying them to the results of the study.The first was a simple model，one that learned from rewards，and the second model added to this by also learning from the option that was not chosen.The third model was the most complete and took the full context into account，with equal weight given to punishment avoidance and reward seeking.For example，obtaining no outcome rather than losing a point is weighted equally to gaining a point rather than having no outcome.
   Comparing the experimental data to the models，the team found that teens' behavior followed the simple reward-based model while adults' behavior matched the complete，contextual model. "Our study suggests that teens are more receptive to rewards than they are to punishments of equal value，" said senior author Dr.Sarah-Jayne Blakemore. "As a result，it may be useful for parents and teachers to frame things in more positive terms."

（1）It can be learned from the study that

C

C

.
A．a(chǎn)dults made choices faster than teens
B．a(chǎn)dults understood rewards better than teens
C．teens reacted better to reward than punishment
D．teens were aware of the outcome of each choice
（2）What do we know about the three computational models？

B

B

A．They reflected people's strong desire for punishment avoidance.
B．They gave circumstances different degrees of consideration.
C．They paid equal attention to reward and punishment.
D．They shaped the behavior of people at different ages.
（3）The underlined word "receptive" in the last paragraph probably means

C

C

.
A．a(chǎn)ccustomed
B．disagreeable
C．responsive
D．sympathetic
（4）According to the writer，which of the following statements works best for teens？

D

D

A． "If you insist on doing things in this way，you will lose ten points."
B． "If we had talked about this earlier，you wouldn't have made the mistake."
C． "If you want to approach a problem differently，you can talk to your parents."
D． "If you hand in your assignment ahead of time，you will get an extra in return."