Is your ADHD brain fog actually CDS?

Many people with inattentive ADHD feel like something is missing from their diagnosis. That missing piece might be cognitive disengagement syndrome, or CDS: a cluster of symptoms including daydreaming, confusion, daytime sleepiness, and more.

CDS isn’t officially its own disorder. But scientists and clinicians are beginning to recognize it as something distinct from ADHD — though it often overlaps.

Pediatric psychologist Melissa Miller explains how CDS differs from ADHD, what it looks like, and why it’s linked to anxiety and depression. She also shares early research on treatment, plus the strengths that may come with it.

• Listen: The “devastating” findings of a decades-long ADHD study

• Watch: Why people with ADHD quit therapy (and how to make it work for you)

Rae Jacobson: We get emails from people saying, "I was diagnosed previously with ADHD, inattentive presentation, and it fit to some degree, but it felt like it wasn't fully capturing my experience as well. And then I came across this, and it feels like it's answering more to me."

Ever feel like your brain is just numb? Like you have to do something, you know what that thing is, you know how to do it, and you just can't? What if that awful feeling had a name, and one day, at least, a treatment?

I have inattentive ADHD, and when I was diagnosed years ago now, I was looking over the paperwork, this packet describing my brain back to me in black and white, and a term jumped out: "Potential Sluggish Cognitive Tempo." At 21, dazed and overwhelmed by the process, I had no idea what that meant.

What I did know was that it sounded bad and embarrassing. And by that point, I had more than enough of feeling bad and embarrassing. But it stayed with me, like bad and embarrassing things tend to, because sometimes my mind feels numb, like someone ironed out all the wrinkles in my brain, leaving it flat and smooth and unable to act.

This is especially excruciating when it happens and I'm on a deadline. Other times I get lost in my own mind and only realize I haven't been paying attention when someone says — or let's be real, snaps — "Yo, pay attention!" or God forbid, "Rae, what do you think?"

In moments like this, I've wondered, "Is this that? Is my brain actually sluggish? Is this what that packet was trying to tell me?" So when I heard that "Sluggish Cognitive Tempo" had gotten a much-needed name change — it's now called Cognitive Disengagement Syndrome, or CDS — I got curious.

And it turns out that while Cognitive Disengagement Syndrome does overlap with ADHD, it's actually its own thing, and it's kind of a big deal.

03:12 The evolving understanding of Cognitive Disengagement Syndrome.

Melissa Miller: Something that I have been trying to do more of and hope to continue is making sure that people that see individuals for anxiety and depression are aware of CDS. People that work in sleep clinics, that they're aware of CDS too, because that's another place that someone might end up if they're having significant CDS symptoms.

Rae: My guest today is Melissa Miller. She's a pediatric psychologist at Cincinnati Children's Hospital. Melissa works with people who have ADHD and Cognitive Disengagement Syndrome. She's also a researcher studying CDS: what it is, how it works, and what treatments might actually help.

So, in this episode of "Hyperfocus," what is Cognitive Disengagement Syndrome? Because if you've ever felt like there was more to your ADHD diagnosis, this one might be for you. Let's start with a basic, straightforward question, which is: What is Cognitive Disengagement Syndrome?

Melissa: What we do know about CDS is it's this cluster of symptoms or behaviors that is related to ADHD but also distinct. But it's not technically a disorder of any kind at this time. And it's represented by symptoms such as mental confusion or fogginess, excessive daydreaming or mind wandering, zoning out.

And then rather than a hyperactivity, more of a hypoactivity, so maybe slowed behaviors, lethargy. We see that there's a lot of daytime sleepiness, especially difficulties in the morning. So that waking up, the alertness is kind of a thing we see.

I've also heard from parents before describe differences in kids with CDS taking a really long time, for example, in the shower, because it's an ideal place to daydream, right? There's nothing else going on.

Rae: I have to say, I'm feeling — I don't know whether it's seen exactly or a little freaked out — unclear. How do people describe what it's like? Like what they're going through with this?

Melissa: People have a lot of different explanations of it, and it's actually something we're working on qualitative research right now. I'm thinking of this one quote that someone said about how it's like drudging through mud each day.

It feels like it's so effortless to get through things. You feel slowed down. You're trying to get towards the end goal or where you're going, but it's effortless the whole time.

Rae: That makes a lot of sense, that it's like if it feels like everybody around you is moving streamlined, like mermaids through water, and you're slogging along.

So, CDS, there are parts of it that do sound a lot like ADHD, like you're moving more slowly, your sense of time is maybe a little bit different. But it's not ADHD. You said before that they're distinct things.

Melissa: CDS has been explored since the 1980s, and at one point, it was thought that CDS symptoms could potentially be a way to maybe identify this pure version of ADHD inattentive presentation. So, are these symptoms actually representing these kids or teens, adults that don't have the hyperactivity?

With additional research since then and over the past few decades, we've seen that they're highly related, especially to the inattentive symptoms, but they're still distinct.

07:44 The distinct differences between external ADHD distractions and the internal nature of CDS.

Rae: That also brings up a big question for me, though, which is: How would you know? I have inattentive ADHD. A lot of the things you just described sound like me, which I think is why I'm just personally interested in this question. But how would you know if you had CDS?

Melissa: As far as the parsing apart, a few different things that you can think about. So ADHD is represented by this external distraction. So things around you in the environment, kind of like your brain's noticing everything all at once, maybe.

Whereas for individuals with CDS, they might be internally distracted. So, distracted by their own thoughts, excessively daydreaming, or almost just having a blank mind at times.

One of the other things we might know that there's difficulties starting or keeping your attention on tasks. For ADHD, it might be that difficulty sustaining attention, whereas for CDS, it might be more of slow processing or even a lower alertness to even get started on a task.

Rae: Personally, I can be distracted by both things. I am a champion level space cadet and, not to toot my own distraction horn, but I've also been known to get distracted by someone's cute shoes as they pass me on the street.

Melissa says that 25 to 40 percent of people with ADHD also have CDS. But not everyone with ADHD has CDS, and not everyone with higher CDS symptoms has ADHD. But since symptoms can look really similar, teasing the two apart can be hard.

Luckily, clinicians like Melissa have figured out that the difference can be assessed, at least in part, by figuring out what a person is doing when they're distracted.

Melissa: So, for example, in a classroom, a kid that has ADHD, predominantly inattentive presentation, teachers might be able to see that they're externally distracted still because they might be looking around the room instead of seeming like they're doing their assignment.

Whereas someone with CDS might look like they're working on their assignment, but they might just be staring at it. So they're not distracted by things around them, but they're just like — they're on the same problem for 10 minutes.

And it's not that they're not putting effort in. They might be daydreaming, or it might be this mental confusion piece too.

Rae: When I think of confusion, I think of somebody who's kind of dotty and not really with it or maybe doesn't understand what's happening around them. Is that what you mean when you're saying confusion?

Melissa: From an individual's perspective, we've had people say before that they have to think through what someone said to them multiple times before they fully are grasping it.

And they might have to ask people to repeat what they said to fully almost put it together in their mind, and also how to respond. And sometimes they might say something and it might sound confusing to other people because maybe that full processing didn't happen yet.

Rae: With that in mind, how would CDS affect somebody's life? If somebody's listening to this and they're like, "Is this me?" what does that look like day to day?

Melissa: We see that there are impacts on academics, so difficulties especially with organization and homework. Social difficulties that also can look a little bit different from the social difficulties we see for individuals with ADHD. So for CDS, we see maybe more of this social withdrawal or a lack of inserting yourself into conversations, initiating those relationships.

Rae: Do you find that that's because, with everything you just described, maybe needing to hear something more than once or finding that you need a little extra time to process what's being said or what's happening around you, people feel like they either can't keep up socially or they end up in embarrassing situations?

Or maybe people think that they're not listening or not being attentive and thoughtful when they are just really trying to navigate a lot of information?

Melissa: I absolutely think that could be part of it. So thinking about initiating a conversation, even though it can seem easy for some people, it is kind of multiple steps. You have to think about what you're going to say, how you're going to approach them, and then also just responding in conversations.

If you're taking a longer time to process what someone else said and think through your own thoughts, it might cause a longer delay than what other people would think is appropriate, which could lead to maybe avoiding social interactions. Because if you start to feel uncomfortable in them, you might want to avoid that feeling too.

Rae: I get that. It's interesting because as you're talking and I kind of came into this with the "Is this part of my profile?" I'm actually feeling like it's not. Because if anything, I feel like people are like, "Could you slow down a little bit?" I'm from New York City and that causes a lot of speed in the way that I interact with people.

Melissa: Just like ADHD, we know that not everyone with ADHD is the same and what they experience is not always the same. And I think the same thing is true for CDS. So maybe some of these symptoms could be true for some people, but maybe other ones aren't. And I think that's part of still figuring out how CDS is best conceptualized.

Rae: So kind of what you're saying is it is sort of possible that I could have this because not everyone has every symptom.

Given that I may have some symptoms but not others, and given that this question has genuinely weighed on my mind for many years, I asked Melissa to do something wildly unprofessional, and that is to diagnose me during an interview over video chat after knowing me for like 20 minutes. What can I say? Your girl loves answers.

If I came in and I said, "Listen, my thoughts are unbelievably distracting, I have inattentive ADHD, sometimes it feels like my brain has gone fully numb. It is not under my control. Even information that I think I know, I can't get. And when I need it most, like a test or an interview, for example, these things that I know to be there aren't accessible to me.

And it feels like it takes me longer than other people to do things. And sometimes I need to hear directions, especially if they involve moving my body in any direction in any way, four or five times." So with all that, and acknowledging that this is not how you would do this in a professional setting, would you diagnose me with CDS?

Melissa: I will give a conservative answer here and say it could be likely. If you wanted to have the answer, it would be more of a full evaluation where we're assessing for kind of pulling apart those ADHD and CDS symptoms as well as potentially other things that could be going on for individuals with either ADHD or CDS. I feel like that was not a great answer, but I wouldn't feel comfortable.

Rae: Oh, you're too professional. Oh no! I celebrate your professionalism and am very impressed. But that said, should one person such as myself have CDS, how would you treat it?

Knowing that I have access to ADHD medication, I am diagnosed with ADHD. If someone came to you and did get the professional evaluation that would allow you to say, "Yes, I'm comfortable telling you that you have this," what would that treatment look like?

Melissa: This is an area that I'm super interested in, and similar to other aspects of where the field is with CDS, there's not a lot of information. What we do know is there's some evidence that interventions traditionally for inattentive symptoms of ADHD can be helpful.

Other research has shown that behavioral sleep interventions could potentially be helpful in reducing some impairments with CDS. Having a routine in the morning where you're up, alert, and getting active right away, as well as mindfulness interventions potentially.

Rae: We know now more about how ADHD medication works and that it focuses more on the alertness and reward centers of the brain. Is that effective for CDS?

Melissa: So this also, the research is very limited on it, but there is some support for stimulant and non-stimulant medication for individuals with CDS. But there's also been some research showing that the response to stimulants might be lower or slower for individuals that have elevated CDS.

Rae: Oh, that is fascinating. Because I would imagine that people often mistake CDS or simply have CDS and ADHD together, and what works for the majority of people with ADHD doesn't work for you, that could make treatment very complicated.

Melissa: Exactly. Yeah.

Rae: Frustratingly, despite the fact that we've known about CDS or "Sluggish Cognitive Tempo" since the '80s, we still don't have great ways to treat it. But Melissa is actively researching this right now.

She and her colleagues are doing a study asking adults with CDS about the treatments they've tried and what's worked. They're looking at medications, supplements, therapies, coping skills, and even things like self-medication with tobacco or alcohol or marijuana.

It's work with huge implications because as Melissa explains, the consequences of leaving CDS untreated can be really serious. I would imagine that a lot of people who experience CDS have probably had some negative feedback in their lives.

And I got to wonder that without the research that you're now working on, if a lot of people have felt that this is a failure on their part, a flaw. Do you see that it affects people's self-image?

Melissa: We do see that CDS is associated with internalizing conditions, so things like anxiety, depression, and also suicidal ideation as well.

Rae: Is it something where when people get a better sense of this, they feel some amount of "Oh"? Like I remember the relief of diagnosis. I would imagine that for somebody with CDS, that could feel like a weight off, like "Oh, this has a name."

Melissa: I have received a lot of messages that way, whether it's through my clinical work or also emails from people that come across it. My colleagues have received emails similar too. "ADHD felt like it didn't really fit for me for 20, 30 years of my life, and I just came across this, and it felt like it perfectly described me."

And so I do think having a name to it can be a relief in that way. The hard part is that oftentimes the next question is: "Now what can I do?"

Rae: Yeah. And from where you are in your research, it sounds like right now the jury's still kind of out. We've talked a lot about the downsides of CDS: mental confusion, slow processing time, lethargy — all words that feel not great.

This is a problem across a lot of how CDS and even ADHD are described. The language we use to talk about the symptoms can feel almost punitive and certainly embarrassing. Being told your brain is confused and lethargic is hardly a boon for self-esteem.

But Melissa told me that that's a function of what the research has focused on so far. Scientists can spend years looking at the negatives before they even consider the positives. But thanks to clinicians like Melissa, that's slowly changing. And in this case, at least, researchers are starting to look at the adaptive parts of CDS as well.

18:25 The potential creative strengths and unique mental sanctuaries associated with the syndrome.

Melissa: There are potentially strengths of CDS, and we don't necessarily have the research on that yet, but it's actively being conducted. Having a bigger imagination, creative talents, thinking about if you're daydreaming and spending time in your head, what kind of things can you come up with? So we're still exploring that, and it's something that I hope to be able to focus more on.

Rae: I love that because I feel like most of the things that I've done that were deeply creative came out of bouts of intense inner mind dwelling. And creativity is a massive strength.

And also, I will say that while we've been talking, one of the things I was thinking about is when you mentioned the shower, is like: I'm almost never bored. It's just not part of my life, because I always have a world into which I can retreat and just roam around.

And I have talked to people who don't have that and get bored very easily. And to be fair, they tend to be more effective than I am in terms of output, but I think there is something to be said for having a sanctuary in your mind that you can just be in and that belongs to you.

Melissa: I love that you mentioned that. It reminded me of something I heard from a patient of mine who had talked about how they are more than happy to spend hours in their own mind, and it's comforting and it's fun.

So when I ask kids, "What do you do in your free time? What's your hobby?" most people aren't going to probably think of daydreaming or spending time in your head, but it was enjoyable for them, and they would spend as much time as they could doing it.

Rae: It's not necessarily always a thing to be overcome. Sometimes it's a gift that you get. And can I ask? You are not exactly a personal stranger to this experience. You have ADHD, right?

Melissa: Yes. So I do have ADHD. I would say I don't necessarily identify with CDS symptoms as much, which I think is interesting.

Rae: Can I ask what kind of ADHD you have? What type?

Melissa: I have combined presentation, so I do have inattentive symptoms as well as hyperactivity and impulsivity.

Rae: Is that what helped you get into this work? What drew you to doing this?

Melissa: Actually, it was not what initially drove me into ADHD or CDS. Getting into this field is what helped me understand myself more and reflect on, "Oh wait, I identify with this."

But no, I actually in undergrad, I was a psychology major, and at one point, I had the opportunity to work at a summer camp, a summer treatment program for kids with ADHD. And actually implementing the program was life-changing for me.

I just saw how much improvement each kid could make, not only with the traditional ADHD symptoms, but I also saw confidence increase, their social relationships increase. And I don't think I realized it initially in that moment, but maybe it was that I identified with some of those kids.

So going from getting a lot of that — they're used to getting maybe not-so-great feedback, corrective feedback — and how rewarding and motivating getting positive feedback is for all the good things that people are doing instead of focusing on the things we're trying to correct.

Rae: Can I ask you one final question? What is the Melissa's perfect world CDS five years from now? What does this look like?

Melissa: My dream is to have more knowledge on effective treatments and also have more awareness and understanding of CDS overall. Because with more knowledge that CDS exists, we're going to help more people and have people be able to understand themselves and their brains better.

Rae: Many thanks to Melissa Miller for coming on the show. We will definitely have her back to talk about the results of some of that research she mentioned. I'm excited about that.

For now, the team here at "Hyperfocus" is curious. Had you heard of CDS before this episode? Do the symptoms that Melissa talked about resonate with you, either with or even more than an ADHD diagnosis? We want to know! Leave us a comment. We love hearing from you.

That's it for this episode of "Hyperfocus." See you soon.

"Hyperfocus" is hosted by me, Rae Jacobson. Our producer is Cody Nelson, and Anna Ross-Child is our senior podcast producer. Julie Subrin helps with booking. Our music comes from Blue Dot Sessions. Our research correspondent is Dr. KJ Wynn.

Video is produced by Max McKenzie and edited by Alyssa Shea. Our associate director of content development is Calvin Knie. Briana Berry is our production director, and Neil Drumming is our editorial director. If you have any questions for us or ideas for future episodes, write me an email or send a voice memo to hyperfocus@understood.org.

This show is brought to you by Understood.org. Our executive directors are Laura Key, Scott Cocchiere, and Jordan Davidson. Understood.org is a nonprofit organization dedicated to empowering people with learning and thinking differences like ADHD and dyslexia. If you want to help us continue this work, donate at understood.org/give.