The last discussed study provided solid evidence that when pleasure is experienced from music (particularly in a manner that exhibits chills), that feeling of pleasure arises out of measurable psychophysiological emotional arousal. It left us with a hint of wonder about whether dopamine plays a role in such pleasure, as the anticipation-reward pattern of pleasure when listening to music seems comparable to the anticipation-reward pattern that dopamine seems to play a major role in based on other studies.
Salimpoor, V., Benovoy, M., Larcher, K., Dagher, A., &amp; Zatorre, R. (2011). Anatomically distinct dopamine release during anticipation and experience of peak emotion to music Nature Neuroscience, 14 (2), 257-262 DOI: 10.1038/nn.2726
...previous neuroimaging studies have implicated emotion and reward circuits of the brain during pleasurable music listening, particularly the ventral striatum, suggesting the possible involvement of dopaminergic mechanisms. However, the role of dopamine has never been directly tested.Ventral stri-what? The striatum is a region of the brain that actively uses dopamine for its purposes and contains other, more specific nuclei of interest. It has been connected to the experience of reward in previous studies. "Ventral" essentially means "lower."
|Striatum, Thalamus, and Amygdala|
The putamen (also called the lenticular (it looks like a lens) nucleus) and the caudate (it looks like a tail) nucleus make up the striatum. The most significant citation of research that involved the ventral striatum is that of Anne J. Blood and R. Zatorre (again): Intensely Pleasurable Responses to Music Correlate With Activity in Brain Regions Implicated in Reward and Emotion [PDF]. It's important to note that the striatum has been associated with dopamine and reward, which I'll talk more about later.
There is some previous work that involved the subject of dopamine, but it isn't research that directly tested its involvement to the degree that this study does. The most significant of that research is that of V. Menon and D.J. Levitin (who is at McGill, of course): The Rewards of Music Listening: Response and Physiological Connectivity of the Mesolimbic System [PDF].
Side note: Daniel Levitin is a name worth remembering. He wrote This is Your Brain on Music, which was the first book that I read that dealt with this subject matter. That book, as well as his research mentioned above, was cited in the first study that I discussed in my last post.
The authors of this research found participants who experience chills in response to certain pieces of music. That should sound familiar if you read my last post. In fact, both of these studies began with a pool of 217 respondents, which seems to strongly indicate the same group of people. It's likely that after running the tests discussed in the initial study, they kept using the same people for this one. The tests designed for this study use a Positron Emission Tomography (PET) scanner as well as a Functional Magnetic Resonance Imaging (fMRI) unit. Using both of these brain imaging devices in a study enabled them to benefit from the advantages of each and even overlay their information to make certain discoveries.
Even with the complex background, the results of this study are surprisingly simple. Dopamine was found to be released (most significantly) in the caudate nucleus and the nucleus accumbens (NAcc). The NAcc is part of the ventral striatum.
|Striatum and Amygdala|
The results get better. Because the researchers were able to compare the timing of neurological activity to the timing of participant-indicated pleasure (and chills) during the music, they determined that the caudate releases dopamine when the listener is anticipating a chill, a moment of peak pleasure, and that the NAcc releases dopamine when the reward, the peak pleasure, arrives.
|This figure pretty much says it all.|
This is downright exciting, because before music was used as a stimulus during research about dopamine and the limbic reward system, researchers had to measure anticipation and reward separately. With music, it has now been demonstrated, researchers can measure the transition between the two in real time. This also gives us insight into how the brain responds to the abstract stimulus of music and related anticipation.
I tried to limit the length of my discussion of this research so that I could have room at the end of this post for other things. With that in mind, I highly recommend reading Jonah Lehrer's blog post reviewing the study, as he uses a couple great quotes from the research and also discusses the role of anticipation in music in a fairly effective and very approachable way (he cites Leonard Meyer too - surprised?).
I can quickly think of a few pieces of music that reliably give me chills and elicit profound emotional responses. Franz Biebl's arrangement of Ave Maria and Z. Randall Stroope's arrangement of I Am Not Yours are the choral works that come to mind. These would actually not qualify as selections for this research for two reasons; they have words and I have performed them before. Those characteristics invite additional variables to the possible causes of emotional activity in the brain, and I find it valuable that these researchers made the attempt to avoid such interferences. After such a study, however, I would be very interested to find out how people's brains act differently when listening to a chill-inducing piece that they have performed.
The strongest emotional reaction from me in response purely to musical sounds comes from German Brass's arrangement and performance of J.S. Bach's Toccata and Fugue in D minor. The first time I heard it I almost cried when the final chord was held. Call me a sap, but my reaction is almost that severe every time I listen to that recording.
There have been some interesting neurological studies demonstrating the similarity between brain activity while performing an action or experiencing a stimulus and while imagining the same action or stimulus. Before looking up videos for the three pieces I mentioned, I first imagined bits and pieces of each, and while merely imagining their sounds I experienced chills. This has happened to me before, and I would be very interested to gather neurological images of brains imagining a chill-inducing musical moment in comparison to when they actually hear the music.
While reading these studies I consistently found tangential relationships to the subject of learning. Consider this passage from the Discussion section of this research:
This subregion of the striatum is interconnected with sensory, motor and associative regions of the brain and has been typically implicated in learning of stimulus-response associations...Studying this proposed model of associative learning by using music as a stimulus could be very effective. These authors express an interest in determining whether the anticipation that they studied is more a result of participants having learned the specific sounds of their musical selections or of participants having learned the contextual cues present in most western music. I suspect that study of people experiencing pleasure during the first listen of a piece of music or the first listen of a style of music that follows rules they are unfamiliar with would be able to address that question as well as mine about the location of neurological activity during one's initial pleasurable experience in response to a piece of music.
previous studies involving rewards such as food and smoking that contain a number of contextual predicting cues...also found dorsal striatum dopamine release. Conversely, in studies in which there were no contextual cues or experience with the drugs involved, dopamine release was largely observed in the ventral striatum...
as rewards become better predicted, the responses that initiated in the ventral regions move more dorsally in the striatum.
The authors of this research do attempt to determine if the activity of the caudate and the NAcc are the same when chills aren't present, and do so by repeating certain analyses with the moments that participants experienced chills ignored. They conclude that activity is similarly correlated to pleasure, but I think this really needs to be studied in people who do not experience chills in response to music. If you look again at the last figure above, you'll see that the most dramatic changes in activity occur during the experience of a chill. Since "the specific experience of chills is not necessary to result in neural activity in the striatum," could we please see if the same dramatic changes occur for those who don't experience chills, and then appropriately compare analyses of the different scenarios? I hope we get to, sometime.
Gee, I hope I wrote enough.