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The Language of Emotions in Music

The enjoyment of music differs across dementia types.

The enjoyment of music differs across dementia types and could be something important to consider in the application of music therapies.

By Sharpley Hsieh

Patients who have been diagnosed with dementia are helping scientists determine which areas in the brain are necessary for identifying emotions in music.

Music is said to be like shorthand for emotions. The power of music to convey emotion is one of the main reasons people listen to and enjoy music.

The study of music and emotions in music is currently a hot topic in cognitive neuroscience. A number of important findings have surfaced in recent years to answer some important questions.

First, are emotions in music universally understood? Scientists who interviewed members of isolated tribes have shown that music seems to be a common language across all people. For instance, the Mafa tribe live in a remote area in Africa and many tribe members had never previously heard any Western music. Despite this, they were still able to identify feelings in Western music at a level that was above chance performance.

Another critical question has been what happens in our brains when we listen to music. Studies have shown that hearing music and the consequent pleasure we experience is associated with the release of dopamine in the brain. Dopamine release is associated with other enjoyable activities like eating chocolate.

Finally, scientists are also interested in asking which areas of the brain are critical for us to know about emotions in music. Does it rely on brain regions known to be important for recognising other emotions, such as when we understand the meaning of a smile or frown on a face? Or does the understanding of emotions in music gather additional brain resources?

One way to answer this question is to study patients who have a diagnosis of dementia. This is the question that I have been asking in my study.

“Dementia” is a broad term used to describe several conditions that cause a loss of cells in the brain. A range of symptoms can be observed when this happens, including a deterioration of important intellectual skills. For example, patients can experience severe losses in memory for recent events, have difficulty with language communication, an inability to make and follow through with plans, control their own behaviour, and problems understanding the meanings of emotions that are expressed on a face or heard in a voice.

Importantly, some of these problems are more common in certain dementias. The loss of memory is typically seen in individuals with Alzheimer’s disease. In contrast, problems with behaviour and language are severely affected in patients with frontotemporal dementia, which is the second most common type of dementia in people under 65 years of age.

The patterns of behaviour and symptoms observed in dementia can be linked with areas in the diseased brain. The reason for this is that the brain, while complex, is highly organised. It consists of two hemispheres connected by a band of nerve fibres called the corpus callosum. The hemispheres are divided into the frontal, temporal, parietal and occipital lobes. A number of other very important structures are located deeper within the brain.

For example, in Alzheimer’s disease a structure called the hippocampus is severely diseased, and this has been associated with the severity of the memory problems that patient’s experience. By studying patients with Alzheimer’s disease, we now know that the hippocampus is critical for normal memory function.

Patients with dementia may therefore help us to understand which areas in the brain are necessary for identifying feelings in music. Very little research had been done in this area until recently. However, any findings we make have the power to add to our understanding of how the brain works and, possibly, be applied to the use of music therapy for patients with dementia.

Our Study

We recruited people who had been given a diagnosis of dementia. Some individuals had Alzheimer’s disease and others had semantic dementia, which is a type of frontotemporal dementia whereby patients experience a severe loss of language and factual knowledge but retain their everyday memory. We also asked volunteers of a similar age and background, but who did not have a diagnosis of dementia, to participate as a comparison group.

Everybody in the study was asked to listen to pieces of music and to identify the emotion that was represented in the tune. We used melodies created by scientists at the International Laboratory for Brain, Music and Sound Research in Montreal, Canada. The melodies were composed to represent feelings of happiness, sadness, fear (or being scared), and a sense of peacefulness. These melodies have been used in other clinical populations but not applied to patients with different dementias.

Participants in the study were also invited to have a magnetic resonance imaging (MRI) scan to provide detailed images of the structural integrity of their brains. Damage to the brain, which can occur as a result of dementia but also other medical conditions such as stroke or cancerous tumours, can been seen on MRI scans.

Our Results

We found that patients with dementia had difficulty identifying emotions in music compared with healthy adults of the same age. In the two dementia groups, patients with semantic dementia experienced more difficulty with this task than those who had Alzheimer’s disease. This means that not all dementia types experience the same degree of impairment when identifying emotions in melodies. The practical implications of these results may be that the enjoyment of music differs across dementia types and could be something important to consider in the application of music therapies.

Next, we analysed the MRI scans and used sophisticated computerised imaging techniques to look at which areas of the diseased brain are associated with performance on the music task. Our results showed that both the left and right parts of the brain were critical.

On the right side of the brain, a structure called the amygdala, which is shaped like an almond and located within the temporal lobe, was important. Critically, this area overlapped significantly with the region that correlated significantly with the recognition of emotions in facial expressions. These findings were expected and largely consistent with a body of research which shows that this particular structure, and also some others that surround it, are important for the processing of emotions.

Interestingly, we also found that the left side of the brain was important for recognising musical emotions. The areas that were critical involved regions devoted to language and verbal skills. What this means is that understanding and feeling emotional content in music draws upon language-based resources in the brain.

Thus music and language, although seemingly different at a superficial level, may in fact be more similar than we had originally contemplated. Both are sound sequences that evolve over time. Both involve rhythmic and melodic patterns. Both consist of basic elements (such as words and notes) that are organised according to specific rules (such as grammar and rules relating to musical keys and harmony). And both are capable of communicating a message. These similarities may be the reason why the brain devotes common regions to both music and language.

Essentially, our findings show that structures in both halves of the brain are involved in appreciating music. We make contributions to the cognitive neuroscience of sound and add to our understanding of how the brain works when we hear music.

Where to Next?

More questions are always raised by findings from research. Do patients with differing dementia types enjoy music in the same way? Will a diagnosis of dementia mean greater enjoyment of music for some patients whereas the sound of music is no longer pleasurable for others? These are important questions to answer with further research.

More critically, the answers for these questions may in turn help patients who have a form of dementia. It is a way for scientists to give back to these individuals and their families.

Sharpley Hsieh is a Postdoctoral Fellow with the Frontier Frontotemporal Dementia Research Group at Neuroscience Research Australia.