Musicians who learn a new melody demonstrate enhanced skill after a night’s sleep

A new study that examined how the brain learns and retains motor skills provides insight into musical skill.

Performance of a musical task improved among pianists whose practice of a new melody was followed by a night of sleep, says researcher Sarah E. Allen, Southern Methodist University, Dallas.

The study is among the first to look at whether sleep enhances the learning process for musicians practicing a new piano melody.

The study found, however, that when two similar melodies were practiced one after the other, followed by sleep, any gains in speed and accuracy achieved during practice diminished overnight, said Allen, an assistant professor of music education in SMU’s Meadows School of the Arts.

“The goal is to understand how the brain decides what to keep, what to discard, what to enhance, because our brains are receiving such a rich data stream and we don’t have room for everything,” Allen said. “I was fascinated to study this because as musicians we practice melodies in juxtaposition with one another all the time.”

Surprisingly, in a third result the study found that when two similar musical pieces were practiced one after the other, followed by practice of the first melody again, a night’s sleep enhanced pianists’ skills on the first melody, she said.

“The really unexpected result that I found was that for those subjects who learned the two melodies, if before they left practice they played the first melody again, it seemed to reactivate that memory so that they did improve overnight. Replaying it seemed to counteract the interference of learning a second melody.”

The study adds to a body of research in recent decades that has found the brain keeps processing the learning of a new motor skill even after active training has stopped. That’s also the case during sleep.

The findings may in the future guide the teaching of music, Allen said.

“In any task we want to maximize our time and our effort. This research can ultimately help us practice in an advantageous way and teach in an advantageous way,” Allen said. “There could be pedagogical benefits for the order in which you practice things, but it’s really too early to say. We want to research this further.”

The study, “Memory stabilization and enhancement following music practice,” will be published in the journal Psychology of Music.

New study builds on earlier brain research in rats and humans
Researchers in the field of procedural memory consolidation have systematically examined the process in both rats and humans.

Studies have found that after practice of a motor skill, such as running a maze or completing a handwriting task, the areas of the brain activated during practice continue to be active for about four to six hours afterward. Activation occurs whether a subject is, for example, eating, resting, shopping or watching TV, Allen said.

Also, researchers have found that the area of the brain activated during practice of the skill is activated again during sleep, she said, essentially recalling the skill and enhancing and reinforcing it. For motor skills such as finger-tapping a sequence, research found that performance tends to be 10 percent to 13 percent more efficient after sleep, with fewer errors.

“There are two phases of memory consolidation. We refer to the four to six hours after training as stabilization. We refer to the phase during sleep as enhancement,” Allen said. “We know that sleep seems to play a very important role. It makes memories a more permanent, less fragile part of the brain.”

Allen’s finding with musicians that practicing a second melody interfered with retaining the first melody is consistent with a growing number of similar research studies that have found learning a second motor skill task interferes with enhancement of the first task.

Impact of sleep on learning for musicians
For Allen’s study, 60 undergraduate and graduate music majors participated in the research.

Divided into four groups, each musician practiced either one or both melodies during evening sessions, then returned the next day after sleep to be tested on their performance of the target melody.

The subjects learned the melodies on a Roland digital piano, practicing with their left hand during 12 30-second practice blocks separated by 30-second rest intervals. Software written for the experiment made it possible to digitally recorde musical instrument data from the performances. The number of correct key presses per 30-second block reflected speed and accuracy.

Musicians who learned a single melody showed performance gains on the test the next day.

Those who learned a second melody immediately after learning the target melody didn’t get any overnight enhancement in the first melody.

Those who learned two melodies, but practiced the first one again before going home to sleep, showed overnight enhancement when tested on the first melody.

“This was the most surprising finding, and perhaps the most important,” Allen reported in the Psychology of Music. “The brief test of melody A following the learning of melody B at the end of the evening training session seems to have reactivated the memory of melody A in a way that inhibited the interfering effects of learning melody B that were observed in the AB-sleep-A group.”— Margaret Allen

Children of Blind Mothers Learn New Modes of Communication

A loving gaze helps firm up the bond between parent and child, building social skills that last a lifetime. But what happens when mom is blind? A new study shows that the children of sightless mothers develop healthy communication skills and can even outstrip the children of parents with normal vision.

Eye contact is one of the most important aspects of communication, according to Atsushi Senju, a developmental cognitive neuroscientist at Birkbeck, University of London. Autistic people don’t naturally make eye contact, however, and they can become anxious when urged to do so. Children for whom face-to-face contact is drastically reduced—babies severely neglected in orphanages or children who are born blind—are more likely to have traits of autism, such as the inability to form attachments, hyperactivity, and cognitive impairment.

To determine whether eye contact is essential for developing normal communication skills, Senju and colleagues chose a less extreme example: babies whose primary caregivers (their mothers) were blind. These children had other forms of loving interaction, such as touching and talking. But the mothers were unable to follow the babies’ gaze or teach the babies to follow theirs, which normally helps children learn the importance of the eyes in communication.

Apparently, the children don’t need the help. Senju and colleagues studied five babies born to blind mothers, checking the children’s proficiency at 6 to 10 months, 12 to 15 months, and 24 to 47 months on several measures of age-appropriate communications skills. At the first two visits, babies watched videos in which a woman shifted her gaze or moved different parts of her face while corresponding changes in the baby’s face were recorded. Babies also followed the gaze of a woman sitting at a table and looking at various objects.

The babies also played with unfamiliar adults in a test that checked for autistic traits, such as the inability to maintain eye contact, not smiling in response to the adult’s smile, and being unable to switch attention from one toy to a new one. At each age, the researchers assessed the children’s visual, motor, and language skills.

When the results were compared to scores of children of “sighted” parents, the five children of blind mothers did just as well on the tests, the researchers report today in the Proceedings of the Royal Society B. Learning to communicate with their blind mothers also seemed to give the babies some advantages. For example, even at the youngest age tested, the babies directed fewer gazes toward their mothers than to adults with normal vision, suggesting that they were already learning that strangers would communicate differently than would their mothers. When they were between 12 and 15 months old, the babies of blind mothers were also more verbal than were other children of the same age. And the youngest babies of blind mothers outscored their peers in developmental tests—especially visual tasks such as remembering the location of a hidden toy or switching their attention from one toy to a new one presented by the experimenter.

Senju likens their skills to those of children who grow up bilingual; the need to shift between modes of communication may boost the development of their social skills, he says. “Our results suggest that the babies aren’t passively copying the expressions of adults, but that they are actively learning and changing the way to best communicate with others.”

"The use of sighted babies of blind mothers is a clever and important idea," says developmental scientist Andrew Meltzoff of the University of Washington’s Institute for Learning and Brain Sciences in Seattle. "The mother’s blindness may teach a child at an early age that certain people turn to look at things and others don’t. Apparently these little babies can learn that not everyone reacts the same way."

Meltzoff adds that there are many ways to pay attention to a child. “Doubtless, the blind mothers use touch, sounds, tugs on the arm, and tender pats on the back. Our babies want communication, love, and attention. The fact that these can come through any route is a remarkable demonstration of the adaptability of the human child.”

We assume people stare at us

People often think that other people are staring at them even when they aren’t, vision scientists have found.

In a new article in Current Biology, researchers at The Vision Centre reveal that, when in doubt, the human brain is more likely to tell its owner that they’re under the gaze of another person.

“Gaze perception – the ability to tell what a person is looking at – is a social cue that people often take for granted,” says Professor Colin Clifford of The Vision Centre and The University of Sydney. 

“Judging if others are looking at us may come naturally, but it’s actually not that simple – our brains have to do a lot of work behind the scenes.”

To tell if they’re under someone’s gaze, people look at the position of the other person’s eyes and the direction of their heads, Prof. Clifford explains. These visual cues are then sent to the brain where there are specific areas that compute this information.

However, the brain doesn’t just passively receive information from the eyes, Prof. Clifford says. The new study shows that when people have limited visual cues, such as in dark conditions or when the other person is wearing sunglasses, the brain takes over with what it ‘knows’.

In their study, the Vision Centre researchers created images of faces and asked people to observe where the faces were looking.

“We made it difficult for the observers to see where the eyes were pointed so they would have to rely on their prior knowledge to judge the faces’ direction of gaze,” Prof. Clifford explains. “It turns out that we’re hard-wired to believe that others are staring at us, especially when we’re uncertain.

“So gaze perception doesn’t only involve visual cues – our brains generate assumptions from our experiences and match them with what we see at a particular moment.”

There are several speculations to why humans have this bias, Prof. Clifford says. “Direct gaze can signal dominance or a threat, and if you perceive something as a threat, you would not want to miss it. So assuming that the other person is looking at you may simply be a safer strategy.”

“Also, direct gaze is often a social cue that the other person wants to communicate with us, so it’s a signal for an upcoming interaction.”

There is also evidence that babies have a preference for direct gaze, which suggests that this bias is innate, Prof. Clifford says. “It’s important that we find out whether it’s innate or learned – and how this might affect people with certain mental conditions.

“Research has shown, for example, that people who have autism are less able to tell whether someone is looking at them. People with social anxiety, on the other hand, have a higher tendency to think that they are under the stare of others.

“So if it is a learned behaviour, we could help them practice this task – one possibility is letting them observe a lot of faces with different eyes and head directions, and giving them feedback on whether their observations are accurate.” 

Subconscious mental categories help brain sort through everyday experiences

Your brain knows it’s time to cook when the stove is on, and the food and pots are out. When you rush away to calm a crying child, though, cooking is over and it’s time to be a parent. Your brain processes and responds to these occurrences as distinct, unrelated events.

But it remains unclear exactly how the brain breaks such experiences into “events,” or the related groups that help us mentally organize the day’s many situations. A dominant concept of event-perception known as prediction error says that our brain draws a line between the end of one event and the start of another when things take an unexpected turn (such as a suddenly distraught child).

Challenging that idea, Princeton University researchers suggest that the brain may actually work from subconscious mental categories it creates based on how it considers people, objects and actions are related. Specifically, these details are sorted by temporal relationship, which means that the brain recognizes that they tend to — or tend not to — pop up near one another at specific times, the researchers report in the journal Nature Neuroscience.

So, a series of experiences that usually occur together (temporally related) form an event until a non-temporally related experience occurs and marks the start of a new event. In the example above, pots and food usually make an appearance during cooking; a crying child does not. Therein lies the partition between two events, so says the brain.

This dynamic, which the researchers call “shared temporal context,” works very much like the object categories our minds use to organize objects, explained lead author Anna Schapiro, a doctoral student in Princeton’s Department of Psychology.

"We’re providing an account of how you come to treat a sequence of experiences as a coherent, meaningful event," Schapiro said. "Events are like object categories. We associate robins and canaries because they share many attributes: They can fly, have feathers, and so on. These associations help us build a ‘bird’ category in our minds. Events are the same, except the attributes that help us form associations are temporal relationships."

Supporting this idea is brain activity the researchers captured showing that abstract symbols and patterns with no obvious similarity nonetheless excited overlapping groups of neurons when presented to study participants as a related group. From this, the researchers constructed a computer model that can predict and outline the neural pathways through which people process situations, and can reveal if those situations are considered part of the same event.

The parallels drawn between event details are based on personal experience, Schapiro said. People need to have an existing understanding of the various factors that, when combined, correlate with a single experience.

"Everyone agrees that ‘having a meeting’ or ‘chopping vegetables’ is a coherent chunk of temporal structure, but it’s actually not so obvious why that is if you’ve never had a meeting or chopped vegetables before," Schapiro said.

"You have to have experience with the shared temporal structure of the components of the events in order for the event to hold together in your mind," she said. "And the way the brain implements this is to learn to use overlapping neural populations to represent components of the same event."

During a series of experiments, the researchers presented human participants with sequences of abstract symbols and patterns. Without the participants’ knowledge, the symbols were grouped into three “communities” of five symbols with shapes in the same community tending to appear near one another in the sequence.

After watching these sequences for roughly half an hour, participants were asked to segment the sequences into events in a way that felt natural to them. They tended to break the sequences into events that coincided with the communities the researchers had prearranged, which shows that the brain quickly learns the temporal relationships between the symbols, Schapiro said.

The researchers then used functional magnetic resonance imaging to observe brain activity as participants viewed the symbol sequences. Images in the same community produced similar activity in neuron groups at the border of the brain’s frontal and temporal lobes, a region involved in processing meaning.

The researchers interpreted this activity as the brain associating the images with one another, and therefore as one event. At the same time, different neural groups activated when a symbol from a different community appeared, which was interpreted as a new event.

The researchers fashioned these data into a computational neural-network model that revealed the neural connection between what is being experienced and what has been learned. When a simulated stimulus is entered, the model can predict the next burst of neural activity throughout the network, from first observation to processing.

"The model allows us to articulate an explicit hypothesis about what kind of learning may be going on in the brain," Schapiro said. "It’s one thing to show a neural response and say that the brain must have changed to arrive at that state. To have a specific idea of how that change may have occurred could allow a deeper understanding of the mechanisms involved."

Michael Frank, a Brown University associate professor of cognitive, linguistic and psychological sciences, said that the Princeton researchers uniquely apply existing concepts of “similarity structure” used in such fields as semantics and artificial intelligence to provide evidence for their account of event perception. These concepts pertain to the ability to identify within large groups of data those subsets that share specific commonalities, said Frank, who is familiar with the research but had no role in it.

"The work capitalizes on well-grounded computational models of similarity structure and applies it to understanding how events and their boundaries are detected and represented," Frank said. "The authors noticed that the ability to represent items within an event as similar to each other — and thus different than those in ensuing events — might rely on similar machinery as that applied to detect clustering in community structures."

The model “naturally” lays out the process of shared temporal context in a way that is validated by work in other fields, yet distinct in relation to event perception, Frank said.

"The same types of models have been applied to understanding language — for example, how the meaning of words in a sentence can be contextualized by earlier words or concepts," Frank said. "Thus the model and experiments identify a common and previously unappreciated mechanism that can be applied to both language and event parsing, which are otherwise seemingly unrelated domains."

Smell of rosemary ‘may improve memory’

Reframing Stress: Stage Fright Can Be Your Friend

Fear of public speaking tops death and spiders as the nation’s number one phobia. But new research shows that learning to rethink the way we view our shaky hands, pounding heart, and sweaty palms can help people perform better both mentally and physically.

Before a stressful speaking task, simply encouraging people to reframe the meaning of these signs of stress as natural and helpful was a surprisingly effective way of handling stage fright, found the study to be published online April 8 in Clinical Psychological Science.

"The problem is that we think all stress is bad," explains Jeremy Jamieson, the lead author on the study and an assistant professor of psychology at the University of Rochester. "We see headlines about ‘Killer Stress’ and talk about being ‘stressed out.’" Before speaking in public, people often interpret stress sensations, like butterflies in the stomach, as a warning that something bad is about to happen, he says.

"But those feelings just mean that our body is preparing to address a demanding situation," explains Jamieson. "The body is marshaling resources, pumping more blood to our major muscle groups and delivering more oxygen to our brains." Our body’s reaction to social stress is the same flight or fight response we produce when confronting physical danger. These physiological responses help us perform, whether we’re facing a bear in the forest or a critical audience.

For many people, especially those suffering from social anxiety disorder, the natural uneasiness experienced before giving a speech can quickly tip over into panic. “If we think we can’t cope with stress, we will experience threat. When threatened, the body enacts changes to concentrate blood in the core and restricts flow to the arms, legs, and brain,” he explains. So, “cold feet” is a real physiological response to threat, not just a colorful expression.

"Lots of current advice for anxious people focuses on learning to ‘relax,’—you know, deep, even breathing and similar tips," says Jamieson. Such calming techniques, write the authors, may be helpful in situations that do not require peak performance. But when gearing up for a high-stakes exam, a job interview, or, yes, a speaking engagement, reframing how we think about stress may be a better strategy.

Then how can people reap the benefits of being stressed without being overwhelmed by dread? To answer that question, Jamieson and co-authors Matthew Nock, of Harvard University and Wendy Berry Mendes of the University of California in San Francisco, turned to the Trier Social Stress Test. Developed in 1993 by Clemens Kirschbaum and colleagues, this experiment relies on fear of public speaking and has become one of the most reliable laboratory methods for eliciting threat responses.

In the study, 69 adults were asked to give a five-minute talk about their strengths and weaknesses with only three minutes to prepare. Roughly half of the participants had a history of social anxiety and all participants were randomly assigned to two groups. The first group was presented information about the advantages of the body’s stress response and encouraged to “reinterpret your bodily signals during the upcoming public speaking task as beneficial.” That group also was asked to read summaries of three psychology studies that showed the benefits of stress. The second group received no information about reframing stress.

Participants delivered their speech to two judges. On purpose, the judges provided negative nonverbal feedback throughout the entire five-minute presentations, shaking their heads in disapproval, tapping on their clipboards, and staring stone-faced ahead. If study subjects ran out of things to say, the judges insisted that they continue speaking for the full five minutes. Following the speech, participants were asked to count backwards for five minutes in steps of seven beginning with the number 996. The evaluators again provided negative feedback throughout and insisted that participants start over if they made any mistakes.

Confronted with scowling judges, participants who received no stress preparation experienced a threat response, as captured by cardiovascular measures. But the group that was prepped about the benefits of stress weathered the trial better. That group reported feeling that they had more resources to cope with the public speaking task and, perhaps more tellingly, their physiological responses confirmed those perceptions. The prepped group pumped more blood through the body per minute compared to the group that did not receive instruction.

Surprisingly, this study also found that individuals who suffer from social anxiety disorder actually experienced no greater increase in physiological arousal while under scrutiny than their non-anxious counterparts, despite reporting more intense feelings of apprehension. This disconnect, argue the authors, supports the theory that our experience of acute or short-term stress is shaped by how we interpret physical cues. “We construct our own emotions,” says Jamieson.