There is only one type of ADHD with three presentations.

Understanding the three presentations of ADHD with Bart and Lisa Simpson and Calvin from Calvin and Hobbes.

Attention Deficit Hyperactivity Disorder (ADHD) is a neurodevelopmental condition that affects individuals differently depending on the presentation and combination of symptoms they experience, which can change over a lifetime. ADHD is typically categorized into three main presentations, but not types.

1. ADHD, Predominantly Inattentive Presentation (ADHD-I): This presentation is characterized by difficulty maintaining attention, staying organized, and completing tasks. Individuals experiencing ADHD-I are often described as forgetful, easily distracted, and prone to daydreaming. They do not show the hyperactivity associated with other presentations of ADHD. This presentation is more common in adults and females, who may be labeled as "spacey" or disorganized. It is important to note that about half of inattentive-only people who never had any impulse-control problems have a new attention disorder called sluggish cognitive tempo or cognitive disengagement syndrome (CDS, not ADHD).

2. ADHD, Predominantly Hyperactive-Impulsive Presentation (ADHD-HI): In contrast, people experiencing this form of ADHD struggle with hyperactivity and impulsivity. They may exhibit restless behavior, such as fidgeting or an inability to sit still, and often act impulsively without considering consequences. This presentation is commonly diagnosed in younger children, particularly boys, since the hyperactive symptoms are more outwardly noticeable.

3. ADHD, Combined Presentation (ADHD-C): The most common presentation, ADHD-C, is a combination of both inattentive and hyperactive-impulsive symptoms. Individuals with this type display significant difficulties with attention, focus, impulsivity, and hyperactivity, making it more challenging to manage daily tasks.

These ADHD presentations can often be reflected in fictional characters who exhibit these distinct traits. Let’s look at three well-known characters—Lisa Simpson, Bart Simpson, and Calvin from Calvin and Hobbes—and how they align with the different ADHD presentation.

Lisa Simpson, ADHD-I.

Lisa Simpson: A Case for ADHD, Predominantly Inattentive (ADHD-I)

Lisa Simpson from The Simpsons can be seen as an example of ADHD, Predominantly Inattentive (ADHD-I). While Lisa excels academically and is deeply invested in intellectual and creative pursuits like playing the saxophone and reading, her personality shows traits of inattentiveness. She can become lost in her thoughts, focused on abstract ideas and ideals to the point that she may appear distracted or disconnected from her surroundings.

Though Lisa is highly organized compared to other characters, her tendency to deeply immerse herself in intellectual activities can cause her to miss what's going on around her, a hallmark of ADHD-I. Her character’s introspective nature and academic focus reflect a more internal struggle with attention, in contrast to the hyperactivity often associated with ADHD.

Bart Simpson, ADHD-HI. 

Bart Simpson: ADHD, Predominantly Hyperactive-Impulsive (ADHD-HI)

On the other end of the spectrum is Bart Simpson, who perfectly exemplifies ADHD, Predominantly Hyperactive-Impulsive (ADHD-HI). Bart’s behavior is marked by a high level of energy, constant movement, and frequent impulsivity. He struggles to sit still, is often found disrupting class, and engages in risky behaviors without thinking about the consequences.

Bart’s impulsivity is also evident in his quick decision-making, where he often blurts out responses or takes action without considering the rules or the impact on others. His constant need for excitement, physical activity, and immediate gratification aligns closely with the traits of ADHD-HI. Unlike Lisa, who is more inwardly distracted, Bart’s ADHD is externalized through hyperactive behavior, making him the embodiment of ADHD-HI.

Calvin, ADHD-C. 

Calvin from Calvin and Hobbes: ADHD, Combined Presentation (ADHD-C)

Calvin from the comic strip Calvin and Hobbes is a classic representation of ADHD, Combined Presentation (ADHD-C), where both inattentive and hyperactive-impulsive symptoms are prevalent. Calvin is a daydreamer who frequently loses focus on schoolwork and responsibilities, preferring to dive into his imagination and create elaborate fantasy worlds. This aligns with the inattentive side of ADHD, where he struggles with tasks requiring sustained focus.

At the same time, Calvin has boundless energy and often engages in spontaneous, adventurous activities with his stuffed tiger, Hobbes. His restless nature and impulsivity—whether he's getting into trouble or interrupting adults with outrageous comments—showcase his hyperactive and impulsive traits. Calvin’s combination of daydreaming, distractibility, and excessive energy makes him a prime example of ADHD-C.

ADHD is a multifaceted condition that manifests in different ways depending on the individual and the type they experience. As we’ve heard from multiple guests on our Wise Squirrels podcast over and over, no two people are ever the same. Through fictional characters like Lisa, Bart, and Calvin, we can observe how ADHD presents itself across different spectrums:

• Lisa Simpson represents the more introspective, inattentive traits of ADHD-I, where focus and mental engagement become challenges despite her high intelligence.

• Bart Simpson illustrates the hyperactive and impulsive side of ADHD-HI, showing an outward, disruptive energy that often leads to risky behavior.

• Calvin, with his vivid imagination and high energy, is a blend of both, reflecting the Combined Presentation (ADHD-C), where inattention and hyperactivity coexist.

These characters give us a glimpse into the varied ways ADHD can manifest, helping to break down common stereotypes and providing relatable examples of how diverse and complex the condition can be.

ADHD is a single condition that manifests in varied ways.

The representations of Bart and Lisa Simpson and Calvin from Calvin and Hobbes highlight the different presentations of ADHD rather than distinct and separate types. By understanding ADHD as a single condition that manifests in varied ways—whether through inattentiveness, hyperactivity, impulsivity, or a combination of both—these characters exemplify the fluid nature of the disorder.

Their traits serve as a reminder that individuals with ADHD can experience shifts in their symptom presentation over time or in different contexts, as research has shown that ADHD is not fixed but evolves across a person’s life. These characters, while often categorized differently, reinforce that ADHD is one condition with multiple expressions, allowing for a broader understanding of how the disorder impacts behavior and development.

In essence, these presentations—whether inattentive, hyperactive-impulsive, or combined—demonstrate that ADHD is not about fitting into rigid categories but rather about recognizing the spectrum of symptoms that can change and adapt over time.