Saturday, December 18, 2021

Research Roundup: "Default Mode & Frontal Executive Network Interactions Enable Interoceptive Attention & Mindfulness"

 Welcome back! Coming up, I'll be catching up on recently published research in the mindfulness, performance, and neuroscience arena. Here's a summary of this recent paper from Mishra et al. (2020) (full text)

What this study is about:

- Attention is a large part of cognitive control, and can be further subdivided into attention to external and internal sensations (exteroception and interoception.) The neural basis of exteroception is pretty well studied. Interoception, which can be trained through mindfulness practice, is a little more of a black box still. 

- This study looks mainly at the neural processes underlying distraction during interoceptive tasks (here, an attention to breathing task.)

What they did:

- N=161 subjects performed a finger-tap response after every two cycles of inhalation/exhalation

- The authors used the variability in this response as a marker of attention fluctuation. Greater consistency in finger tap responses = improved interoceptive attention control.

- They divided the results into "attentive trials" - where finger taps were most consistent, and "distracted trials" - where there was less consistency in finger tap responses. Brain activity and functional connectivity was analyzed during both types of trials.

Key questions: 

- Does consistency (on finger taps) relate to performance on cognitive tasks?

- What does the neural basis of consistent performance look like within individuals?

    - During attentive trials, there should be increased functional connectivity/brain activity in regions of the salience and cingulo-opercular networks.

    - During distracted trials, there should be increased dorsolateral prefrontal cortex (DLPFC) activation because of the increased cognitive effort required to suppress distractions.


- On distracted trials, increased DLPFC activity was seen (executive control region), and decreased precuneus activity was seen (a default mode network region.)

    - Increased DLPFC activity likely reflects greater effort needed to suppress distraction and reorient to the task.

    - Decreased precuneus activity may reflect the need for default mode network suppression during distractor suppression.

- Increased functional connectivity between DLPFC and precuneus was also noted during distracted trials, perhaps due to needing more cognitive control regions to suppress the default mode network when reorienting to task. 

- On attentive trials, there was increased functional connectivity between the anterior cingulate cortex (ACC) and insula.

    - These regions are involved in sustained attention, self regulation and emotion regulation - all of which are involved in interoceptive attention.

    - When subjects are on task (attentive), default mode network suppression is not required (as opposed to what was seen in the distracted trials.)

- Increased trait mindfulness in subjects correlates with increased functional connectivity between DLPFC and precuneus on distracted trials, and with increased functional connectivity between ACC and insula on attentive trials. 

    - Interpretation:  better mindfulness skills = stronger functional connectivity between the brain regions involved in distraction suppression and reorientation to tasks involved in interoceptive attention.

Friday, May 21, 2021

The Snake Run 2021: Lotsa Mud, No Snakes

 In a weird stressful uncertain year, it makes sense that I would return to running. Also in a weird twist of fate, after months of neurologic complications from occupationally-acquired Covid-19, running has caused the least amount of headaches and brain fog. Maybe it's the helmet or more constant vibration from gravel/mountain bike terrain, but cycling any distance continues to be...complicated.

There was a recent New York Times article about the public health professionals and frontline healthcare workers struggling to do objectively safe things post-vaccination (e.g. be outside.) The mental block/secondary post-traumatic stress syndrome is real. It took weeks of fretting to sign up for my first event in over a year. One with fewer than 100 people spread out outside over miles of trail, 5 miles from home, in a community with declining infection rates. As a fully vaccinated *and* post-Covid-antibodied individual. At a certain point you need a little exposure therapy, and a start on releasing a year's worth of built-up trauma. I may have also chosen the 6-hour race option over the 3-hour race option primarily because there would be fewer people on the start line. 

Turkey Mountain (there are no turkeys) is familiar territory, but I actually rarely run on the upper lot trails, where one can find the Snake Trail (from which this event gets its name.) I have a tendency to get lost up there, to the surprise of no one. My sole landmark is an old rusted washer/dryer. If someone ever hauls that blessed object out of the woods, I will likely never make it back to the parking lot. Anyhow, the kind people who came up with this race format gave us a 3.75 mile loop on the Snake Trail, and a shorter 0.5 mile loop somewhere over on the blue trail to run circles around when you ran out of time to do another 3.75 mile loop. Whoever runs the most miles in the allotted time gets a scary snake trophy. The course is well-marked, flat, and with mild to moderate trail sharks. You have to watch your footing, but it doesn't require 100% of your brainpower. Not a bad way to ease back into the running world...


1. Successfully remember to change clocks for daylight savings.

2. Put running clothing on.

3. Drink a lot of coffee.

4. Cue thunderstorms.

It was raining lightly at the start. I put every piece of gear I might want into my car, since for an extra 50 yards of running I could self-support whatever the heck I needed from the comfort of the parking lot. The first lap passed without incident in a nice light rain and a not-too-drenched trail. A handful of fast dudes went blasting out at a pace way faster than my technical skills will take me, but I comfortably ran 8-9 minute pace according to Garmin. About three-quarters of the way through my second lap the skies absolutely opened up, which was fine until my eyeballs flooded with water, and anyone with a contact lens prescription greater than -5 knows what I'm talking about. I almost always run with a visor or hat partially because of this. This was the one item I managed to leave at home, so I comically and blindly staggered out of the woods and stole my boyfriend's hat off his head. Having one's day ended by loss of contact lenses in thunderstorm would be embarrassing. 

The Snake trail turned into more and more of a mud slog as time went on, with full-on tiny muddy lakes most of the way. TL;DR version of the subsequent 5 hours: tiny hip stabilizing muscles got real tired and the 7th and 8th (final) laps I "ran" were more of a hobble. I probably did not hydrate enough - had this happened by osmosis I would've been just fine 😂 I did throw down two dark chocolate trail butter packets and about 5 V fuel gels. I made a feeble attempt at the short loop with my remaining time, as I was at 30 miles and the female race record was 31 miles...but my body was not having it. Also there were bigger rocks on the short loop.

My body decided it was cold shortly after I stopped moving, and I decided to sport my swanky swim parka. Credit to SOAS Racing for those tights (and they have pockets.) First place in style and mud-fording: