Too much of a good thing: when people don’t really *get* pain science

I wanted to share a really important post with you all this morning, from the author of Chronically Undiagnosed.

She’s a therapist who is dealing with chronic illness.  Recently, she wrote about her experience attending a chronic pain support group that incorporated some of the theories of modern pain science… but did so very badly.

As someone who fervently believes in what pain science has to offer — it’s what originally inspired me to become a physical therapist– I have often felt many of her same frustrations, when people try to stretch pain science beyond the limits of its intended applications, or when they lump in their own personal beliefs about pain which have nothing to do with the actual scientific literature on the subject.

Reading her post, it sounds as though the social worker leading the class did have a basic understanding of pain science.

(By modern pain science, I mean the school of thought that says that pain is a function of our brains that’s meant to protect us, and as a protective mechanism, it doesn’t always work perfectly, or give us an accurate way to gauge what’s actually happening in our bodies. People can experience devastating injuries and feel no pain, or they can experience excruciating pain from injuries that are technically “minor.”  Pain scientists believe this knowledge can help us develop new treatment approaches, once we begin to tap into the fact that pain is here to protect us.  Some of the original proponents of this approach include David Butler and Lorimer Moseley).

It sounds as though Chronically Undiagnosed’s group leader did present some of these anecdotes, to prove that pain can be subjective.  But she did so in a way that was alienating to the group participants.

Chronically Undiagnosed writes:

“The instructors have cited reports of individuals who have either been injured and experienced no pain, or individuals who thought they were injured (but were not) and experienced extreme pain. One example was of a roofer who landed on a 6-inch nail that went through his steel toed boot who presented in the E.R with reports of excruciating pain. He was medicated for pain and the boot removed where it was discovered that the nail had gone through his shoe but between his toes, resulting in zero tissue damage. Additionally pictures of MRI’s were shown where a person had visible spine damage but no pain.

As someone with an advanced degree who has studied and taught research and statistics, I find fault with their examples. In a scientifically based research study, extreme results such as these are considered “outliers” and are not considered statistically significant. And as someone who has both counseled patients with chronic pain and experienced it daily for over 5 years, I find their assumptions to be not only scientifically incorrect but harmful to people experiencing chronic pain.

And now here come the people touting “modern pain science” as a breakthrough in treating pain. If pain is simply a perception created by the brain, then if we change our brains the pain should go away. When I expressed my concerns to the leader of the group she suggested that leading medical institutions in our country (such as Stanford, where I received “injections” that helped me) are “behind” in understanding pain.”

Reading about her experience made me really frustrated and sad, because I had a totally opposite experience when first presented with this information.

However, when I first came across it (under the guidance of my physical therapist Tim, and through watching physiotherapist Neil Pearson‘s lectures) I understood these stories– which ARE statistical outliers– to simply be examples illustrating how pain works.

They are extreme examples, but they demonstrate the fact that pain does not always provide an accurate indication of what is wrong in our bodies.  These stories are meant to educate, not to give people the impression that they ought to be able to magically “turn off” the pain in their brains tomorrow.

Following this, it sounds as though the social worker leading the group made another key mistake, one that I absolutely can’t stand:

She lumped her own personal beliefs about pain in with the theories of modern pain science, without making any distinction in between the two.

I’ve personally seen this before.  The first doctor who ever told me I had a heightened sensitivity to pain never actually told me about any of the neuroscience research behind this phenomenon (central sensitization).  Instead, she told me I was probably suffering from some form of psychological trauma, and that the only way for me to get better was through psychotherapy.

Years later, when I had finally discovered pain neurophysiology education, I found that the people actually researching modern pain science never talked about childhood trauma (or any other kind of psychological trauma).  They didn’t need to– the theory of pain as an imperfect protective mechanism was enough to explain so many of the things that could sometimes go wrong with it.

That’s not to say that no one, ever, experiences physical pain as a result of emotional trauma.  That’s not what I’m trying to say either.  But it’s wrong to be leading a group where you’re presenting people with the theories of modern pain science, and lump in your own personal beliefs about pain without making a distinction.

She did actually lump in other grains of truth.

Some of the other information Chronically Undiagnosed’s social worker presented is, technically, legitimate.

It is true that MRI’s are not always the best predictors of who will actually experience back pain.  There’s a great book, Back Sense, that talks about this.

In a nutshell, if you were to take 100 people off the street and take an MRI of everyone’s spine, you wouldn’t necessarily be able to tell, just by looking at the MRI’s, who was actually experiencing back pain.

We all experience some degeneration to our spines over time, but sometimes this degeneration can be symptom-less.

However, this information should never be used to tell a group of chronic pain patients they shouldn’t be experiencing any pain!

All of these bits of knowledge, which can be helpful– whether it’s pain science, or Back Sense– are meant to be one piece of the puzzle!

And they are meant to help illuminate aspects of patients’ experience.  They are meant to educate.  

They are not meant to blame people, or make them feel responsible for experiencing pain they shouldn’t be feeling!

I see this far too often in the field of pain science.

As a (hopeful) future physical therapist, I’ve followed a number of physical therapists, writers, and researchers on various social media platforms, hoping to learn more about how the field of pain science is evolving.

Unfortunately, I’ve had to go back and actually “unfollow” a bunch of people, because I see the same thing over and over again.  People will get annoyed and actually downright snarky about patients and fellow medical professionals trying to treat certain conditions which are the subject of controversy– the sort of “gray areas.”

One of these areas, in particular, is the sacroiliac joint.  There are a lot of physical therapists out there who don’t believe sacroiliac joint dysfunction is a real thing.

So I’ll sign on to Twitter, and find that someone I respected and followed to learn more about pain science is tweeting out some kind of derogatory commentary about how “the sacroiliac joint doesn’t really move” and what a “sham” it is that people are trying to treat it.

I suppose the evidence for sacroiliac joint dysfunction is really a topic for another post, however to me it’s just another example of people trying to take pain science too far.

Ultimately, I believe these physical therapists’ anger stems from a good place.  From their perspective, they’re probably tired of seeing other medical professionals “waste” patients’ time by treating them for musculoskeletal causes of pain, when they should be focusing on the nervous system.

But really, there are two sides of the same coin.

Yes, pain originates in our brains.  And our brains can shut pain off, in emergency situations.  

But that doesn’t mean patients’ pain isn’t valid.  That doesn’t mean that, once you put them in a 3-hour class where they hear about extreme examples of people not experiencing pain, they should automatically be able to “turn off” their own pain.

No approach will work if you don’t listen to people.  No approach will work if you aren’t kind.  That’s really the bottom line.

Pain science should be used to educate– not to deny the other potential reasons someone could be experiencing pain.

Just as MRI’s aren’t always accurate indicators of who will have back pain, it doesn’t mean that someone in excruciating pain shouldn’t have an MRI.

All of these things represent aspects of the truth, but no one piece should ever be a substitute for looking at the whole picture.

P.S. Please don’t worry, there are plenty of ways to learn about pain science from people who actually do get it!  

For more, you can check out my Resources section.

I also highly recommend Todd Hargrove’s article Seven Things You Should Know About Pain Science.

 

Pain is like Memory: Dr. Jay Joshi on Central Sensitization

Okay.  I’ve really been looking forward to publishing this post.

Here, we’re revisiting the same great talk by pain physician Dr. Jay Joshi.  In my last post, I outlined what Dr. Joshi says are the four main categories of pain.

Central sensitization is the type that is, unfortunately, the least understood.  And it’s also the type that’s had the biggest impact on my life to date.

What is it?

Central sensitization is a process through which the central nervous system learns to become more sensitive to, or amplify, pain signals.

I struggled with it for years and thought I was crazy, because I had pain that came and went throughout my own body that most of the doctors and physical therapists I saw couldn’t explain.

Central sensitization is a form of memory.

Generally, we think of central sensitization as a sort of a disorder, because of course, it causes so much pain and suffering.

However, as I’ve touched upon in previous posts, central sensitization actually has its roots in some of the same neural mechanisms that allow us to learn new things and store memories.  We “learn” from pain just as we learn from anything else, and our nervous systems can be changed by it.

As Dr. Joshi says:

“Central sensitization is what happens when the brain is exposed to certain experiences or certain memories.  It’s life… it’s being a human.

When you have a certain memory that forms it, becomes part of who you are… it becomes part of your experience.  And your behavior changes as a result of that.

This is not something that happens randomly…  This is something that happens to the neurophysiology of your brain.  It forms memories.  Those circuits get hardwired on your little ‘hard drive’ that’s known as a brain.  The same thing that happens with pain, when you have a chronic pain stimulus.”

The process of central sensitization is not separate from our brain’s other functions– rather, it belongs to them.

I found this happened to me so often, over the years, before I even knew what central sensitization was.

I’d have a painful experience– the first one was when I threw my back out at age 21— and it was like my nervous system was determined not to let me forget about it afterwards.

According to Dr. Joshi, this is exactly how central sensitization occurs, after a painful or traumatic event:

“You have a painful experience, and usually one of the first things that happens is your brain says ‘hey don’t do that again.'”

It’s trying to protect you from doing the same thing that might have caused you to become injured in the first place.

But what happens when that signal doesn’t stop? 

In cases like mine, this process can go on indefinitely.  Your brain keeps trying to protect you, telling you not to repeat certain activities, long past what’s actually necessary or conducive to your well-being.

This is called the wind-up phenomenon— when the brain’s protective mode stays on, and never gets the signal to turn “off” like it should.  Instead, it just keeps repeating the message of “don’t do that again”– even if it’s something that, technically, should be safe for you to do.

Once this process, the pain can sort of build on itself, like a snowball effect.  And you can remain in pain, long after the original injury that might have set all this off as healed.

Does all chronic pain cause central sensitization?

Dr. Joshi explains that chronic pain is likely to lead to some degree of central sensitization.  (This is significantly higher than other estimates I’ve heard, such as Dr. Elliot Krane’s figure of 10%).

However, I think Dr. Joshi’s explanation makes a lot of sense.  After all, when you experience chronic pain, you’re basically bombarding your nervous system with opportunities to practice sending pain signals.  Why wouldn’t it get better at doing so, the same way you can get better at playing the piano or riding a bike?

Central sensitization is still a part of my life.

I don’t expect to ever be able to totally reverse the process that first began, for me, at age 21.

However, I was able to make a lot of positive changes and gain back a lot of control over my body through pain neurophysiology education, which I write about a lot on this blog.  (Basically, it involves teaching your nervous system what it’s like to feel safe again, so that it can turn the “volume” back down on the pain).

There’s a lot more to say!

Dr. Joshi has some great thoughts on how to improve the medical profession’s understanding of central sensitization, as well as ketamine infusions– a potentially powerful treatment for patients with central sensitization.

I’ll be sharing more on this coming up– hope you liked this post!

The Four Categories of Pain– Dr. Jay Joshi

Hi everyone!

I’ve just discovered this awesome talk on central sensitization by pain management physician Dr. Jay Joshi.  It’s totally packed with information I want to share with you all– such as why it’s so hard to get help for central sensitization, and how ketamine infusion treatments can help.  There’s so much here, though, that I thought I’d break it down into bite-sized information for you.

So, to start out, let’s look at what Dr. Joshi says are the four main types of pain.  (For the purposes of this blog post, I’m actually jumping ahead to the 8:50 mark– later, we’ll come back to the beginning).  

The four types:

  1. Nociceptive
  2. Neuropathic
  3. Inflammatory
  4. Central Sensitization

1. Nociceptive pain: pain that results from actual tissue damage, or potential tissue damage (like if you’re starting to bend a joint past its normal range of motion).  It is “the common discomfort we have all experienced as a result of injury — a paper cut, a broken bone, or appendicitis, among other things.

More on nociceptive pain and its subtypes

2. Neuropathic pain: involves physical damage to the nerves or the central nervous system itself.  It can also occur when the person has a tumor that’s pressing upon a nerve.

3. Inflammatory Pain: Pain produced by the chemicals our body releases as part of the inflammatory or healing process.  On a small scale, think of how a bruise swells up and is painful to the touch.  This is because our body is sending special cells and chemical messengers to that part of our body in order to heal it– and also to make it painful, so that we know to protect the area.  This is inflammatory pain, and it can also happen on a much larger scale with more serious injuries.

4. Central Sensitization: And here we are– the type of pain that’s most affected my life.  It has to do with the concept of neuroplasticity: that the central nervous system (the brain and spinal cord) can change in response to the things it experiences.

When your body experiences a painful event or an injury, it learns from that experience, the same way it learns from anything.  Practice makes perfect– when your brain gets enough practice at sending pain signals, it gets better at it gets better at it.  In a way, this is for your protection– you learn and become more sensitive to performing the same kinds of actions or motions that may have caused this injury in the first place.

However, as a protective mechanism, central sensitization can sort of backfire.  Eventually, we can reach a point where our nervous systems are trying to protect us too much, when we’re not really at risk of injury anymore.

So these are the four main types.

Unfortunately for those of us suffering from central sensitization, it’s the type of pain that doctors and other medical professionals know the least about.

As Dr. Joshi explains, “there are physicians who claim to be pain physicians… who are anesthesiologists… who don’t even understand it.  And they’re teaching at major programs.  It’s scary.”

Central sensitization is as real a type of pain as any of the other three.  And, as Dr. Joshi says, if you’re going to be able to adequately treat pain as a doctor, you better be aware of all four categories.

***

Dr. Joshi also has some really great analogies which help to explain the phenomenon of central sensitization further.  I’ll be elaborating on some of those in my next post.

I hope this was helpful!

***

Also: you may have noticed that I’ve been playing around with my blog’s format.  I’ve honestly never truly been happy with the appearance of my blog, because I find my options are so limited with premade WordPress themes.  I’m beginning to experiment a little (and even spend a little bit extra!) to try to get things right.  If you have any thoughts or suggestions how improve the appearance of my blog, please let me know!

 

 

 

 

 

Dr. Sean Mackey on a potential reason for chronic pain

Hi everyone!

Here’s an amazing lecture from Dr. Sean Mackey of Stanford University on the various potential causes of fibromyalgia.

On my blog, I tend to focus on the factor that I know has played the largest role most directly in my own life– central sensitization.  The idea that central nervous system can become more sensitive to pain, as a result of physical pain or trauma that a person experiences.

Central sensitization (CS) has played a huge role in my own life, and I’ve come to feel that for me personally, it’s the best way to try to understand my nervous system.  That’s why I’ve written more about CS than I have about fibromyalgia specifically (although, as Dr. Mackey explains, there are other potential causes for fibro that we need more research on as well).

***

I felt like including this lecture for you today because it ties a lot of different things together for me conceptually whenever I’m try to decide where I’m going with this blog.  (It was one of the very first things I linked to in my “Resources” section back in 2013, and I’m still so glad I found it!).

***

One of the points I most appreciate in this talk is when, around the 18:00 mark, Dr. Mackey talks about an evolutionary benefit for our nervous systems learning to become more sensitive to pain.

Usually, when we think about chronic pain/central sensitization, we think of it as some horrible defect of the nervous system.  And yeah, I mean, it kind of is.  Something is definitely not working there the way it was intended.

However, pain is ultimately a mechanism that’s there to keep us safe, and it’s brought me a lot of peace and comfort to remember that.

Dr. Mackey points out that, back in our cave people days, it actually made a lot of sense for our nervous systems to freak out after an injury.  After all, we weren’t living in safe and comfortable houses and getting up to go sit in an office all day.  Instead, we were out there, walking great distances, running, hunting, fighting.

He says:

Pain serves as a survival message for us… Back in the cave people days, when we were out fighting the woolly mammoth and the saber-toothed tiger, when we got injured, it was in our best interest to go sit in a cave and let Nature take its course and heal up that injured limb… Because if you went out and fought them when you were injured, you got eaten, and you didn’t get to pass your genes along.

So it actually made a lot of evolutionary sense for a cave person’s nervous system to freak out after an injury and slow the person down, forcing him or her to rest.   The people who ignored their injuries and went back out there too soon didn’t always make it back to the cave afterwards.

Maybe our nervous systems “learn” to become more sensitive to pain, not because it’s some weird fluke or accident, but because that’s exactly what they were designed to do.  In another place and time, maybe this exact phenomenon is what would have kept us safe.

***

In general, this is how I’ve learned to think of pain, and it’s a perspective that many of the resources I share on my blog are all coming from.

After all, it’s the basis of pain neurophysiology education– to help a chronic pain patient learn to see her nervous system as an overactive alarm system, or an overprotective friend.  Pain is not an enemy; ultimately, it’s a protector.  And once you learn to work with your nervous system, instead of against it, the effects can be really powerful.

***

I really loved this lecture, and also enjoy following Dr. Mackey’s work in general.   He’s involved in some ground-breaking research at Stanford that uses something called fMRI to take real-time pictures of the brain, and exactly that it’s doing when it experiences chronic pain.

You can read more on this in my “Studying Chronic Pain Through Brain Imaging” section– it’s really fascinating!

***

I also wanted to include something positive for you guys, after last week’s post about a doctor who totally blew me off.  I have certainly encountered my struggles in trying to get treatment, but ultimately, the thing to remember is that there are answers out there, and we are not crazy!

Our bodies are trying to protect us– they are just trying a little too hard!

Hope this was helpful, and that you’re all having a great week!

 

The doctor who *almost* helped me (How I developed central sensitization, Part 6)

Okay, so here’s the story of the time I thought I’d found the right person to help me, which of course, made it all the more disappointing when it didn’t turn out to be the case.

In telling my story, I’m choosing to gloss over every little ache and pain I had; every time I thought I had some kind of injury, but no one could actually find anything wrong.  It’s not really necessary to the story, and I don’t want you to get bogged down in negativity.  The point, again, is that I did eventually find answers.

But here’s the story of the first time I thought I’d found them.

***

It was 2006; my first time seeing a physiatrist.  Physiatrists are doctors who specialize in non-surgical options to treat musculoskeletal pain– so, basically, they do everything else.  Their approach is generally thought to be more holistic.  They can provide options such as lidocaine and cortisone injections, but they also look at the patient as a whole person and can recommend lifestyle changes as well.  It’s a pretty cool specialty.

And I was pretty much seeing the best one.  I loved Dr. V. the first time I saw her.  She’d won all kinds of awards for going above and beyond to help her patients.  And she was just so… nice.  She provided me with so much hope.

Dr. V. reassured me that there was no reason, as a healthy person in my early 20’s, I shouldn’t be able to do all of the things I wanted to do.

She recommended a bunch of promising options, including trigger point injections, as well as medical acupuncture, which she actually performed herself.

And she was the first person to really explain to me that my brain was magnifying the sensations of pain I felt, “like a computer.”  My brain was “zooming in” and making what should be a small problem, or no problem at all, look like a big problem.

For a time, I really thought Dr. V. was going to be the one to finally “fix” me, to finally reverse this impossible pattern I’d been dealing with for so long.  I felt like she really got me.

***

Dr. V. seemed to understand that, from time to time, I would come in with pain in a new part of my body, and would need someone to tell me whether, in fact, I had an injury or whether it was just pain.

There were so many times. I felt safe; I felt believed.  I just needed a place to go where someone could tell me whether or not I had an injury or not.  I didn’t always need to be referred to physical therapy, or start some new treatment.  Sometimes, the pain would just diminish once someone actually told me it was safe to ignore it.  (Which, as I later learned, makes 100% sense once you learn about how the nervous system works).

The only thing is, Dr. V. did want to refer me elsewhere: to therapy.  She seemed to understand that my brain was distorting my perception of pain, but she kept coming back to the idea that it had a psychological or emotional cause (which, I would later learn, is not a prerequisite for central sensitization).

She offered me the names of a few different therapists she had come into contact with over the years.  I would go and see them, but nothing ever really “clicked.”  Because we were looking for something that wasn’t there– my pain wasn’t being caused by my emotions.

***

What I really needed, again, was for someone to help me understand my physical pain.  As I’ve explained in my Calming Your Nervous System section of this blog, when you have the kind of chronic pain I had (and still have, to an extent) it’s like your body’s pain protection system has gone into overdrive.  It’s trying to protect you, but it’s stuck in the “on” position all the time.

Luckily, the nervous system is complex, and although there are multiple components involved in keeping this process going, there are other aspects of the nervous system which can be used to turn the system “off.”

One way to do that is to understand, rationally, that your body isn’t actually in danger; that you aren’t actually injured.  This is actually the pain principle behind Pain Neurophysiology Education, the approach to chronic pain treatment that finally helped me.

Of course, I didn’t know any of this at the time, but I sort of stumbled upon this principle myself.  A new part of my body would hurt (or an old one would start hurting again) and it would feel real.  It would feel like something was wrong; something was injured or on the verge of breaking.

That’s why it helped me, to go in and see Dr. V.  To be examined by an actual doctor and be told nothing was wrong.  It helped my nervous system feel “safe” again.  Usually, I’d start feeling better within a day or so after my appointment, before I even got to physical therapy or whatever next treatment she’d recommended.  Because she’d already given my nervous system permission to relax and stop hyper-focusing on that part of my body.  The pain would be able to fade into the background.

And I was okay with this pattern.  It wasn’t ideal, but it was better than anything I’d found yet.  We hadn’t actually been able to break this cycle of mysterious pain that roamed throughout my body, but at least, with Dr. V. I’d been able to find a way to stop it from taking over my entire life when it started to get bad.

***

But here’s the thing.  I was okay with the holding pattern, but Dr. V. was not.  Because I wasn’t actually getting “better” in a linear fashion that she could write in her notes.  And because she could never actually find anything wrong with me.

There was one day I was 10 minutes late for an hour long appointment.  I’d had to take the Red Line to Mass General, where I saw her, and everything about that morning commute had just been a disaster.

And from the moment she walked into the room, everything had changed.  Her face seemed cold, like there was less color in it than usual.

And she told me she didn’t have time to see me that day.  That I’d been taking time away from her other patients; other patients who actually had horrible diseases and disfigurements and reasons to be in pain.

She said she’d tried to help me, but I hadn’t successfully utilized any of the options she’d given me.  And that if I wasn’t going to be responsible about trying to fix my issues, she wasn’t going to have time for me in the future.

And that was that.  I started to cry and attempted to explain myself, but it didn’t matter.  Her mind was made up.

She said she didn’t have time to stay and talk to me if I’d already missed 15 minutes of our 30 minute appointment.   Her secretary, who I’d sort of become friends with, overheard the whole thing and poked her head into the room, gently reminding Dr. V. that my appointment was actually supposed to be for a whole hour.

But it didn’t matter; Dr. V. was so angry at that point that no new information was going to make a difference.  It wasn’t really about the time; it was about getting rid of me.

She didn’t outright tell me never to come back and see her again, but by walking out of the room after 5 minutes, she’d made her message pretty clear.

So I never did.

***

Now that I know so much more about central sensitization, I can see that Dr. V. was wrong on multiple levels.  This is why I like to remind people that central sensitization was actually discovered in rats.  It has to do with brain function and neurons and neurotransmitters, not thoughts and feelings.

Somehow, it was like Dr. V. had vaguely heard of central sensitization somewhere, but hadn’t really gotten the full gist.  A lot of people are like that, actually.  They accept that the nervous system can process pain abnormally, but still think it must have to do with emotions.

And I never actually heard the term from her.  I only learned it once I requested a copy of all of my visit notes and saw it there, in my list of diagnoses.  It was #1: central sensitization.

That whole time– she could have just told me the name for it.  I didn’t even know there was one.  I could have learned about it myself– I could have Googled it.  It was discovered in 1983.  There was more information out there than I was given.

But no.  Central sensitization was just there in two small words, right under a lot of passive-aggressively worded comments about exactly how much of my appointment time I’d missed that last time.

***

It’s sad and it’s really shocking.  I do believe that Dr. V. is a good person who just didn’t have enough information, and who got frustrated.

But it shouldn’t be my job, to get “fired” as a patient and request my own office visit notes, only to finally learn there’s a scientific name for what I was going through that she’d never even bothered to tell me.

I could have looked it up myself and learned about it, instead of going on countless wild goose chases to psychotherapy and the terribly disappointing pain clinic she once sent me to.

***

But at least I have answers now, and you know what?  I think I’m sort of proud of myself for getting as far as I did, on my own.  After all, it basically means I’m a genius, since I was able to stumble upon the main principle of pain neurophysiology education all on my own (right?).

***

As you may know, what really did work for me eventually was to meet a physical therapist who had studied PNE with Neil Pearson.  This physical therapist taught me how to understand my nervous system, and to work with it, instead of against it, and to learn ways to get my body to turn the “volume” of the pain back down.

This is why I feel so, so strongly about PNE, and why I was originally inspired to become a physical therapist.

In a way, Dr. V. is part of my inspiration as well– I see how important it is for healthcare practitioners to actually understand the specifics of how chronic pain works.  It’s not enough to just be an empathetic person, because apparently empathy can be replaced by frustration over time, if a patient isn’t getting better.

If you want to know more about PNE, you can check out the Calming Your Nervous System section of my blog, and also definitely check out the work of Neil Pearson!

Hope this was helpful!