Thursday, November 20, 2014

Memory, Aging, and Distraction

The population in the United States is aging.  That has created a lot of anxiety about the cognitive effects of getting older.  Lots of research suggests that older adults are worse than younger adults on a variety of different thinking tasks.  They remember fewer words from lists they see.  They are slower to respond in many situations.  They have more trouble ignoring distracting information. 

An interesting paper in the April, 2013 issue of Psychological Science by Renee Biss, Joan Ngo, Lynn Hasher, Karen Campbell, and Gillian Rowe suggests that—while these factors may look like they are all aspects of cognitive decline—there are times when these changes may actually be helpful.

In particular, there has been a long line of research in psychology showing that older adults have worse basic recall memory than younger adults.  The typical way to demonstrate this effect is to show participants a list of words and then have them recall the words from that list after a short delay.  College students remember a higher proportion of the words on the list than adults in their 60s and 70s.

The researchers in this study speculate, though, that in many situations there may be subtle reminders of what needs to be remembered in the world.  If older adults pay more attention than younger adults to information that may seem distracting, then that may actually help their memory.

To test this possibility, college students (with an average age of about 20) were compared to older adults (with an average age of about 68.  First, participants saw a list of 20 words that they were told to remember for later.  After a brief delay in which everyone counted backward by 3s starting with the number 74, participants were asked to remember as many words as possible from the list.

After that, participants did a 1-back test. In a 1-back test, a series of pictures are shown, and participants respond with one key when the current picture was identical to the previous picture and with a second key when the current picture was different from the previous picture.  The pictures in this test were all line drawings of objects that were not related to the words that were studied.

On each trial, though, there were words superimposed on the pictures in a different color than the line drawing.  Participants were told that the words were irrelevant to the task and that they should be ignored.  However, eight of those words were items that had actually been presented on the study list.  After doing this 1-back test, participants were asked to recall the list of words again. 

On the initial test, the older adults recalled significantly fewer of the words from the list than the younger adults.  After the 1-back test, older adults recalled more words that had been shown in the 1-back task than words that had not been shown.  In fact, they remembered just about as many of those repeated words as younger adults did.  The younger adults were not affected by the 1-back test.  They remembered words equally well regardless of whether they were repeated in the 1-back test.  In fact, the older adults remembered the repeated words just about as well as the younger adults did, allowing them to overcome the age difference in memory.  Overall, people recalled a little over 30% of the items from the list, so this is not a ceiling effect.

One other interesting finding in this study was that older adults responded slightly more slowly to the pictures when the accompanying word had appeared on the initial list than when it had not.  Younger adults showed no difference in speed to respond to these items.  This finding suggests that older adults were more distracted by items they had seen before than younger adults.  None of the participants included in the analyses explicitly recognized that words from the list had appeared in the 1-back test, so this distraction was happening without awareness.

This research replicates previous work showing that older adults remember less and are more distractible than younger adults.  However, this work also suggests that there is a silver lining to this combination.  If older adults need to remember a piece of information, they may be more likely than younger adults to notice information in the environment that helps them to remember it.  This combination may help them overcome some of their memory limitations.

Thursday, November 13, 2014

Frustration and Violent Video Games

If you talk to people who enjoy violent video games, they give many reasons for playing.  Some just like the chance to do things that they would never do in real life.  Others enjoy the chance to get together with friends and play.  Still others see violent video games as a chance to escape the stresses of daily life and blow off a little steam.

Of course, one problem with asking people why they engage in a behavior is that they often don’t have real insight into the factors that influence their behavior.  As I often say, the reason that so many people need therapy and counseling in their lives is because they are not entirely sure why they do what they do.

An interesting paper in the April, 2013 issue of Psychological Science by Jodi Whitaker, Andre Melzer, Georges Steffgen, and Brad Bushman explored the role of taboo behaviors and frustration in men’s interest in violent video games.

Taboo behaviors are things like cheating and stealing that people know are wrong.  When people are tempted to do something wrong, it is arousing.  They engage in a battle between the strength of the temptation and their willpower.  And, as studies by Dan Ariely and his colleagues point out, we often fail in our efforts to do the right thing.

Presumably, though, if you give in to temptation, then the arousal that comes with the temptation subsides.  If you have the chance to steal a candy bar and you do it, then you no longer feel the temptation so strongly.  If you have the chance to steal that candy bar, and suddenly realize that you are being watched, then you can’t give in to the temptation, but you still may feel the strength of that temptation.  That may cause frustration.

Whitaker, Melzer, Steffgen, and Bushman suggest that this frustration may make violent video games seem more attractive to play than they would be otherwise. 

To test this proposal, college men were brought to the lab and asked to estimate the weight of two common objects using quarters.  They would take a stack of quarters out of a bowl and try to find a stack that was about equal in weight to the object.  (Men were run in this study because women are much less likely than men to be interested in playing violent video games.)

Some participants were given no chance to steal.  The door to the experiment room was kept open, and the experimenter stood watching the participant throughout the study.  A second group of participants was told that the door would be kept closed throughout the study.  These participants had the opportunity to steal some quarters if they wanted.  A third group of participants was told that the door would be kept closed throughout the study, but midway through the experiment, the experimenter came back in and said that actually the door had to be kept open.  This group had the temptation to steal made active, but were then blocked from stealing.

After estimating the weight of the objects, participants rated their current mood, which included a measure of their level of frustration.  Then, they completed a short survey about video games.  They listed the games they play frequently and also rated the attractiveness of eight games.  Half of these games were violent games, and the other half were not violent games. 

Participants who were in a closed room throughout the study did steal some quarters.  On average, participants took almost 75 cents.  Those who had only a limited chance to steal took about 35 cents on average.  Those participants who were in an open room for the whole experiment rarely stole.  As you might expect, the group that had a brief opportunity to steal were significantly more frustrated at the end of the study than those who either had a chance to steal or had no chance to steal at all.

Overall, participants rated the nonviolent video games more attractive than the violent games.  However, the group that briefly had the chance to steal found the violent games significantly more attractive than either of the other groups.  The group that had a chance to steal throughout the study found the violent video games more attractive than those who had no chance to steal.  Statistical analyses demonstrated that the degree of attractiveness of the violent video games for these groups could be explained by people’s level of frustration.

A second study obtained the same pattern of results using cheating on a quiz rather than stealing as the taboo behavior. 

This research suggests that people are attracted to violent video games when they are aroused by a temptation and frustrated in their pursuit of that temptation.  However, there is still an open question about why this happens.  One possibility is that people are attracted to violent video games when they are frustrated, because they hope that playing the game will relieve the frustration.  A second possibility is that this frustration creates arousal and that this arousal makes action attractive. 

Thursday, November 6, 2014

Is That Extra Hour of Study Time Worth It?

It is no surprise that teens and young adults are a pretty sleep-deprived group.  Yesterday morning at 9am, for example, I taught a small class here at the University of Texas.  The students staggered into class looking like they could use a nap.  I also have three teenagers.  They generally stay up late and get up early during the week, hoping to catch up on weekends by sleeping all morning.

There are lots of distractions in the modern world that lead people to stay up late in the night.  For students, though, there is also homework.  On the night before a big exam or a major paper, many students put in a lot of extra study time in order to prepare. 

Does that extra study time help performance in school?

This question was explored in a studying the January, 2013 issue of Child Development by Cari Gillen-O’Neel, Virginia Huynh, and Andrew Fuligni.  They tracked a group of high school students in 9th, 10th, and 12th grade.  At each grade level, students filled out a daily diary for 2 weeks. 

Every evening during the study, the students rated the amount of sleep they got the day before, the amount of time they spent on homework, and they answered questions about any academic problems they had the previous day (like doing poorly on a test and having difficulty understanding new material).

Overall, there was a tendency for high school students to sleep less as they advanced in school.  So, the 9th-grade-students slept an average of 7.6 hours a night, while the 12th-graders slept only 6.9 hours per night.  Students experienced fewer academic problems as they advanced in school.  That means that students are actually learning better school skills over the years. 

The most important result, though, was that when students lost sleep because they spent extra time doing schoolwork, they had significantly more problems the next day than when they got their typical amount of sleep.  This negative effect of extra study time was strongest for 12th-grade-students and weaker for the 9th- and 10th-grade students.

What is going on here?

Sleep is important for many reasons.  It helps memory.  You consolidate memories during sleep.  Sleep also helps you focus and sustain attention.  Sleep also gives you energy to be active.  You are much more likely to be a passive learner when you are tired.  And you learn less when you are passive then when you actively engage with new material.

So, why are high-school Seniors hardest hit? 

The 12th-graders are sleeping least to begin with.  They are just at the edge of their ability to function properly.  When they disrupt their sleep schedule further with extra study, it has strong repercussions for the next school day.  The 9th- and 10th-grade students are a bit more resilient, because they are not as strongly sleep-deprived.

What does this mean?

First off, this study reinforces the general observation that teens and young adults are not sleeping enough.  Getting even an extra 30 minutes of sleep a night would be a huge benefit for this group.

Second, it means that students need to try to spread their work out over longer periods of time.  It is an age-old tradition to cram for exams and to finish papers at the last minute.  There are lots of good reasons to want to avoid cramming.  For example, cramming for an exam may help a student pass that particular exam, but information learned the night before the test is not remembered in the long-term as well as information that is studied over several nights.  If cramming for a test also reduces the amount of sleep a student is getting, then that just adds to the problem.