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Archive for March 2009

Brain Activity Linked While Anticipating Musical Structures

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Neuroscientists at Georgetown University Medical Center have, for the first time, shown what brain activity looks like when someone anticipates an action or sensory input which soon follows.

In the February 25 issue of the Journal of Neuroscience, they say this neural clairvoyance involves strong activity in areas of the brain responsible for preparing the body to move.

The findings were made by using functional magnetic resonance imaging (fMRI) in a group of student volunteers who brought with them favorite music CDs. The scientists examined brain images during the silence between songs, and found it brimming with activity. Other students who listened to music they had never heard in sequence before did not have that same neural bustle.

“This now explains how it is that, even before an anticipated song is actually heard, a person can start to tap fingers, dance, or sing to the music they imagine is coming next,” says Josef Rauschecker, PhD, director of the Program in Cognitive and Computational Sciences (PICCS), at Georgetown University Medical Center.

While it makes sense that song sequences can be memorized and thus anticipated by a listener, no one before has ever documented the brain activity that is underway in the silence between songs, he says.

“The brain is all about anticipation and prediction, yet no one has shown what that looks like in terms of neural action,” says Rauschecker.

He adds that this same process, known as cued associative learning, likely occurs whenever a human is expecting any particular action to happen, be it in sports, music, or language.

“It is how a skier is mentally prepared to go down a familiar course during the Olympics, or how a piano player knows to move fingers along the keyboard to hit the next correct key,” Rauschecker says.

This sounds simple, but it isn’t, he says. “It is not trivial to store a temporal sequence in the brain, because the brain doesn’t have any moving parts like a tape recorder or CD player. The whole brain needs to be involved because it has to be ready to execute that sequence. “

In the students who knew the order of songs on their CD, the researchers found that during the anticipatory silence between the songs excitatory signals passed from the prefrontal cortex to the nearby premotor cortex. The prefrontal cortex is the brain’s “executive” center, which plans and orchestrates complex cognitive behaviors. The premotor cortex and its associated systems, which include the basal ganglia and the cerebellum, is involved in preparing the body to act – perhaps to move or to sing.

“These structures are involved in both thinking and acting, and it appears that music patterns are being stored and learned here,” Rauschecker says.

“We hadn’t anticipated that,” he adds with a laugh. “We didn’t know the premotor areas would be involved.”

All animals have some ability to cognitively predict motor activity, he says. “That’s why a bird can sing. But humans are the most associative of animals, which is why we have such a large prefrontal cortex. We have a lot of sequences that we need to store in order to predict what we should do.”
The Journal of Neuroscience, February 25, 2009, 29(8):2477-2485; doi:10.1523/JNEUROSCI.4921-08.2009
Brain Activation during Anticipation of Sound Sequences.
Amber M. Leaver, Jennifer Van Lare, Brandon Zielinski, Andrea R. Halpern, and Josef P. Rauschecker.

Music consists of sound sequences that require integration over time. As we become familiar with music, associations between notes, melodies, and entire symphonic movements become stronger and more complex. These associations can become so tight that, for example, hearing the end of one album track can elicit a robust image of the upcoming track while anticipating it in total silence. Here, we study this predictive “anticipatory imagery” at various stages throughout learning and investigate activity changes in corresponding neural structures using functional magnetic resonance imaging. Anticipatory imagery (in silence) for highly familiar naturalistic music was accompanied by pronounced activity in rostral prefrontal cortex (PFC) and premotor areas. Examining changes in the neural bases of anticipatory imagery during two stages of learning conditional associations between simple melodies, however, demonstrates the importance of fronto-striatal connections, consistent with a role of the basal ganglia in “training” frontal cortex (Pasupathy and Miller, 2005). Another striking change in neural resources during learning was a shift between caudal PFC earlier to rostral PFC later in learning. Our findings regarding musical anticipation and sound sequence learning are highly compatible with studies of motor sequence learning, suggesting common predictive mechanisms in both domains.

Key words: prefrontal cortex; basal ganglia; auditory; fMRI; learning and memory; motor learning

Written by huehueteotl

March 5, 2009 at 8:52 am

Posted in Neuroscience

Overdoing It? Simple Techniques Can Help Avoid Overindulgence

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Some people overindulge on junk foods or needless shopping sprees when they feel depressed. Others lose control the minute they feel happy. Is there a way to avoid such extreme actions? A new study in the Journal of Consumer Research demonstrates simple techniques that can help people act in their long-term interests rather than indulging in immediate pleasures.

“The recipe is simple,” write authors Aparna A. Labroo (University of Chicago) and Anirban Mukhopadhyay (University of Michigan). “If you are feeling happy, focus on reasons why those feelings will last, and if you are feeling unhappy, focus on reasons why those feelings will pass.”

The authors explain that indulgence is often a result of people trying to improve their mood. People tend to indulge themselves when they believe their happy feelings might pass unless they do something to prolong the good feeling. Others feel miserable and believe they’ll be stuck with the blues unless they do something to improve their mood.

“People strategically manage their actions both to accomplish their long-term interests and to attain immediate pleasures. If they believe they need to take action to regulate their feelings in the here and now, they tend to indulge in immediate pleasures. In contrast, if they believe such actions are not required, they act in their long-term interests,” write the authors.

In one study, the authors presented participants (who were dieters) with line drawings of either smiley or frowny faces. “The results revealed that simply associating a smiley with less transience (coloring with a superfine micro tip, which takes a long time to color, rather than a sharpie, which colors the face in a few short strokes) resulted in people becoming more likely to act their long-term interests and choose an apple as a snack rather than a chocolate,” write the authors.

Next time your misery makes you reach for the hot fudge, take a moment to think about how the feelings will pass. “Simply thinking life is not so bad might actually help you make your life a little better by helping you make a healthy food choice,” the researchers conclude

Journal of Consumer Research, 2009; 0 (0): 090114112928060 DOI: 10.1086/597159

Lay Theories of Emotion Transience and the Search for Happiness: A Fresh Perspective on Affect Regulation.

Aparna A. Labroo and Anirban Mukhopadhyay.

Across six studies, we demonstrate that consumers have beliefs pertaining to the transience of emotion, which, along with their current feelings, determine the extent to which they regulate their immediate affect. If consumers believe that emotion is fleeting, those feeling happy (vs. unhappy) engage in affect regulation because they infer that they need to take actions to maintain their positive feelings. In contrast, if consumers believe that emotion is lasting, those feeling unhappy (vs. happy) engage in affect regulation because they infer that the negative feelings will persist unless they take actions to repair them. These effects are obtained with measured and with manipulated beliefs, and they occur only when the theories pertain specifically to emotion. Implications and areas for future research are discussed.

Written by huehueteotl

March 3, 2009 at 8:46 am

Posted in Psychology