Expertise-related deactivation of the right temporoparietal junction during musical improvisation 2010 Berkowitz and Ansari

Abstract

Musical training has been associated with structural changes in the brain as well as functional differences in brain activity when musicians are compared to nonmusicians on both perceptual and motor tasks. Previous neuroimaging comparisons of musicians and nonmusicians in the motor domain have used tasks involving prelearned motor sequences or synchronization with an auditorily presented sequence during the experiment.

Here we use functional magnetic resonance imaging (fMRI) to examine expertise-related differences in brain activity between musicians and nonmusicians during improvisation – the generation of novel musical–motor sequences – using a paradigm that we previously used in musicians alone. Despite behaviorally matched performance, the two groups showed significant differences in functional brain activity during improvisation. Specifically, musicians deactivated the right temporoparietal junction (rTPJ) during melodic improvisation, while nonmusicians showed no change in activity in this region. The rTPJ is thought to be part of a ventral attentional network for bottom-up stimulus-driven processing, and it has been postulated that deactivation of this region occurs in order to inhibit attentional shifts toward task-irrelevant stimuli during top-down, goal-driven behavior.

We propose that the musicians' deactivation of the rTPJ during melodic improvisation may represent a training-induced shift toward inhibition of stimulus-driven attention, allowing for a more goal-directed performance state that aids in creative thought.

Paywall, https://www.sciencedirect.com/science/article/abs/pii/S1053811909009525

 

Shared originally on Twitter by @Snow Leopard

 

Reading this, seems a lot like this region being involved in attention means that it's a difference between conscious, deliberate, attention and relying on learned abilities. So a musician improvising doesn't actively and attentively think about everything, about every move and every next note, in fact you pretty much turn off the executive/attention and passively follow wherever things take you.

I would bet that you wouldn't find that from musicians learning a new piece, where you have to direct attention, you can't just go with the flow, you are learning the flow. Improvisation is really all about going with the flow, but you can only really do that without significant attention if you have experience, if you can sort of turn of the thinking part of your brain and just let your fingers/hands/arms do what comes naturally. Although to speak of "goal-oriented" in the context of improvising music really shows that the researchers are not experienced musicians and do not understand what goes on during. One thing that isn't there during improvisation is definitely having goals.

And this would be consistent with pwME doing the "effort" task, where executive attention is reduced and so they're relying more on automatic behavior, there is less reasoning and it's more of a "flipping a coin" type of decision-making, more intuitive. This is exactly what would be expected of people having little to no attention and executive reasoning to spare. We rely on automatic, learned, behavior most of the time because attentional reasoning demands too much energy.

 

It is. You have to disconnect most of your attention to play anything well, and all of it to improvise. But improv's not so much a musical skill as a cognitive switching skill. Plenty of good musicians struggle to do it, just as some sportspeople and dancers regularly experience a block to entering the 'zone'.

I've never experienced anything resembling it when I wasn't playing music or dancing. PEM's interesting in that it produces really strange gaps in movement, speech, and musical rhythms that I can't overcome, but it categorically doesn't allow a transition into flow or meditative states. They consume too many resources and the switch doesn't work in the presence of stress.

 

That sounds familiar. I can be completely ready, yet still not manage it. Luckily I only play Irish stuff now, and being late's the norm—you often don't know what tune somebody's starting until you've heard a bit of it.

The most frustrating thing in practice is losing a single eighth or quarter partway through a bar. It throws me off the rhythm and I can't get it right, no matter how familiar the piece or how many times I try. I'll also stumble whilst walking, because I somehow forget to do a step and then I'm trying to take two on the same leg; or I'll be speaking and get lost mid-sentence because I've missed out an article or pronoun.

It's a feature of mild or maybe third-day PEM, where I feel okay enough to start an activity. After 10 minutes I realise I might be okay to do something, but it's definitely not this.

 

Keep in mind this TPJ finding also falsifies the "predictive coding"/"predictive processing" "hierarchical Bayesian model" of exertional fatigue.

(example of the falsified hypothesis: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8983507/ & https://www.frontiersin.org/articles/10.3389/fnhum.2016.00550/full)

The hypothesis basically states that there are various levels of comparison of sensory feedback versus prediction and the model assumes that there is reduced tolerance of prediction error, but instead of increasing attention at the lower levels of the hierarchy (in this case it would be the supplementary motor areas), they hypothesise that there will instead be increased attention at the higher levels of the hierarchy, with greater levels of precision - such as TMJ. Interestingly, their model works backwards to how hierarchical Bayesian model's normally work and indeed the NIH results suggest their hypothesis is incorrect - instead of requiring more precision, the effect seems to be instead increased tolerance of prediction error and less attention to error at higher levels of the hierarchy.

 

I've been a keen amateur dancer all my life but now I can't move in time at all. I guess it's the same problem as whatever it is that makes it difficult to be accurately aware of longer periods of time passing, where you can feel as if 15 minutes has passed but it's actually been two hours or whatever.