When my original article about 'music chills' was published on The Conversation last week (and on several other sites, including Slate, Salon, and ScienceAlert), I was pleased to see a flurry of comments from readers about how deeply they related to the article, and how pleased they were to have a name - frisson - for the familiar experience of aesthetic chills. 

Many comments from readers fell into several thematic categories, and I've addressed them below in relation to my own research on the two thirds of population who seem to experience this phenomenon.

1. Of no surprise to me, many commenters were quick to indicate that they can self-induce frisson through mere mental self-stimulation, which is something that previous research had documented.

Interestingly, what persuaded me to pursue this research study in the first place was my own experiences with frisson, including often triggering the chill-inducing event with my own thoughts, rather than with external stimuli. 

2. Among other comments was the repeatedly cited notion that, "These are just goosebumps, people. Come on!"

However, several prominent studies have clearly documented the startling reality that, while goosebumps are an integral part of frisson, frisson itself is a far more complicated physiological reaction than just plain old goosebumps. Several studies have documented how intensely the brain reacts during a frisson episode:

"Cerebral blood flow changes were measured in response to subject-selected music that elicited the highly pleasurable experience of 'shivers-down-the-spine' or 'chills'. Subjective reports of chills were accompanied by changes in heart rate, electromyogram, and respiration.

As intensity of these chills increased, cerebral blood flow increases and decreases were observed in brain regions thought to be involved in reward, motivation, emotion, and arousal, including ventral striatum, midbrain, amygdala, orbitofrontal cortex, and ventral medial prefrontal cortex. These brain structures are known to be active in response to other euphoria-inducing stimuli, such as food, sex, and drugs of abuse.

This finding links music with biologically relevant, survival-related stimuli via their common recruitment of brain circuitry involved in pleasure and reward" - Blood & Zatorre, 2001; p. 11818

3. Despite these clearly powerful physiological responses that are characteristic of frisson, many readers were incredulous that the experience might legitimately be referred to as a "skin orgasm".

In all actuality, the term is highly accurate, as the neurophysiological structures and neurotransmitters in play are almost identical with the pleasure we derive from food, sex, and even drugs like cocaine: when any of these pleasurable experiences take place, dopamine floods the amygdala and ventral striatum, making us feel safe, peaceful, and euphorically charged. 

4. With that "skin orgasms" reference in mind, many readers couldn't help but parade out their sense of humour. 

@Joel Jones, replying to another Facebook user, said: "[Frisson] happens to me but sometimes too fast and I have to apologise and pretend it was the first time it has happened."

@Juana Searcy, also reacting on Facebook, quipped: "Statistically, I'm pretty sure some of you are faking it…"

Interestingly, Juana is not far off the mark. Despite the fact that she was clearly being cheeky, the results of our 2015 study showed that participants will actually fake frisson episodes in the lab.

In 2009, I had read through several research articles on the topic, all of which used pure self-report measures as a way of assessing whether or not participants were experiencing frisson. In other words, they were simply asking participants to report something along the lines of, "Yep, I'm getting the chills right now."

This seemed unusual to me and led me to devise an innovative methodology to assess authentic frisson episodes.

Rather than simply asking participants to report frisson as they listened to music, I simultaneously monitored their physiological responses in the lab so I would know when their body was truly cascading through the intense cerebral experiences that characterise the event.

We know from previous research by Nikki Rickard from Monash University in Australia that galvanic skin response is an effective way to assess whether or not frisson is occurring. 

By comparing all of these data, I could verify participants' self-reports of frisson, and also parse out when participants were faking the experience. I also suspected that fake responding would skew the results related to personality and may have been skewing results in previously published research.

Surprisingly, many participants did in fact fake frisson episodes during the research process. We even had one participant report 39 frisson episodes in the 10-minute listening session, while the chart that documented his physiological responses remained revealingly placid.

In comparison, the average number of authentic frisson episodes for participants in the study was a mere 2.68 during the same 10-minute listening session, all of which were accompanied by the characteristic physiological indicators.

We were very pleased to discover that when we compared the self-report data to the personality measures (ignoring all physiological data we had collected), the results of our study mimicked almost exactly the results found by other researchers who had relied exclusively on self-report measures of frisson. Specifically, these self-report-only data showed that the most emotionally open listeners experienced frisson to the greatest degree.

However, when we compared our data using a combined self-report/physiological measure of frisson, a new pattern emerged: this time, it was the cognitive elements of the personality trait 'openness to experience' that were most closely associated with an increased disposition to experience frisson.

While we're still attempting to understand why some participants would want to fake frisson in the lab, we know that acquiescence bias - or the desire to be helpful to researchers - causes participants in all kinds of studies to provide false-positives. 

These results simply stress the importance of using appropriate methods to control for and reduce the biased influence that can often occur during social research. 

5. As a side note, many readers incorrectly identified frisson with another unusual physiological experience called ASMR. As Sean Collins over at BuzzFeed has demonstrated, the two experiences may have similarities, but are really quite different, both in form and function.

For those interested in reading more about frisson, Professor David Huron of the Ohio State University School of Music has written the definitive work on the field of music cognition - a highly sophisticated and richly technical text called Sweet Anticipation: Music and the Psychology of Expectation

Mitchell Colver is a PhD student in education at Utah State University. You can listen to his Radio New Zealand National intervie on frisson here.

This article has a Creative Commons Attribution No Derivatives license, so you can republish the article in its original form for free, online or in print, as long as you include the following: This article was originally published by ScienceAlert. Read the original article here.